New Advances in Non-Embryonic Stem Cell Research
The studies cited below are a sampling of the published and peer-reviewed material available on the subject. The list will be updated on a regular basis.
Hematopoietic reconstitution by multipotent
adult progenitor cells: precursors to long-term hematopoietic stem
Marta Serafini and Catherine M. Verfaillie et. al., The Journal
of Experimental Medicine; doi:10.1084/jem.20061115; Epub 2007 Jan
Abstract: For decades, in vitro expansion of transplantable
hematopoietic stem cells (HSCs) has been an elusive goal. Here,
we demonstrate that multipotent adult progenitor cells (MAPCs),
isolated from green fluorescent protein (GFP)-transgenic mice and
expanded in vitro for >40–80 population doublings, are
capable of multilineage hematopoietic engraftment of immunodeficient
mice. Among MAPC-derived GFP+CD45.2+ cells in the bone marrow of
engrafted mice, HSCs were present that could radioprotect and reconstitute
multilineage hematopoiesis in secondary and tertiary recipients,
as well as myeloid and lymphoid hematopoietic progenitor subsets
and functional GFP+ MAPC-derived lymphocytes that were functional.
Although hematopoietic contribution by MAPCs was comparable to control
KTLS HSCs, approximately 103-fold more MAPCs were required for effi
cient engraftment. Because GFP+ host-derived CD45.1+ cells were
not observed, fusion is not likely to account for the generation
of HSCs by MAPCs.
Isolation of amniotic stem cell lines with potential for therapy, Published online: 7 January 2007; | doi:10.1038/nbt1274
Paolo De Coppi1, 3, Georg Bartsch Jr1, 3, M Minhaj Siddiqui1, Tao Xu1, Cesar C Santos1, Laura Perin1, Gustavo Mostoslavsky2, Angéline C Serre2, Evan Y Snyder2, James J Yoo1, Mark E Furth1, Shay Soker1 & Anthony Atala1
1 Wake Forest Institute for Regenerative Medicine, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, NC, 27157-1094, USA.
2 Children's Hospital and Harvard Medical School, 300 Longwood Avenue, Boston, Massachusetts, 02115, USA.
3 These authors contributed equally to this work.
Abstract: Stem cells capable of differentiating to multiple lineages may be valuable for therapy. We report the isolation of human and rodent amniotic fluid-derived stem (AFS) cells that express embryonic and adult stem cell markers. Undifferentiated AFS cells expand extensively without feeders, double in 36 h and are not tumorigenic. Lines maintained for over 250 population doublings retained long telomeres and a normal karyotype. AFS cells are broadly multipotent. Clonal human lines verified by retroviral marking were induced to differentiate into cell types representing each embryonic germ layer, including cells of adipogenic, osteogenic, myogenic, endothelial, neuronal and hepatic lineages. Examples of differentiated cells derived from human AFS cells and displaying specialized functions include neuronal lineage cells secreting the neurotransmitter L-glutamate or expressing G-protein-gated inwardly rectifying potassium channels, hepatic lineage cells producing urea, and osteogenic lineage cells forming tissue-engineered bone.
Isolation and functional characterization
of murine prostate stem cells
Devon A. Lawson et al., Proc Natl Acad Sci U S A. 2007 Jan 2;104(1):181-6.
Epub 2006 Dec 21.
Abstract: The ability to isolate
prostate stem cells is essential to explore their role in prostate
development and disease. In vitro prostate colony- and sphere-forming
assays were used to quantitatively measure murine prostate stem/progenitor
cell enrichment and self-renewal. Cell surface markers were screened
for their ability to positively or negatively enrich for cells with
enhanced growth potential in these assays. Immunohistochemical and
FACS analyses demonstrate that specific cell surface markers can
be used to discriminate prostate stromal (CD34(+)), luminal epithelial
(CD24(+)CD49f(-)), basal epithelial (CD24(+)CD49f(+)), hematopoietic
(CD45(+), Ter119(+)), and endothelial (CD31(+)) lineages. Sorting
for cells with a CD45(-)CD31(-)Ter119(-)Sca-1(+)CD49f(+) antigenic
profile results in a 60-fold enrichment for colony- and sphere-forming
cells. These cells can self-renew and expand to form spheres for
many generations and can differentiate to produce prostatic tubule
structures containing both basal and luminal cells in vivo. These
cells also localize to the basal cell layer within the region of
the gland that is proximal to the urethra, which has been identified
as the prostate stem cell niche. Prostate stem cells can be isolated
to a purity of up to 1 in 35 by using this antigenic profile. The
remarkable similarity in cell surface profile between prostate and
mammary gland stem cells suggests these markers may be conserved
among epithelial stem cell populations.
Ex Vivo Large-Scale Generation of Human Platelets from Cord
Blood CD34+ Cells
Takuya Matsunaga et al., Stem Cells. 2006 2006 Dec;24(12):2877-87.
Epub 2006 Sep 7.
Abstract: In the present investigation, we generated
platelets (PLTs) from cord blood (CB) CD34(+) cells using a three-phase
culture system. We first cultured 500 CB CD34(+) cells on telomerase
gene-transduced human stromal cells (hTERT stroma) in serum-free
medium supplemented with stem cell factor (SCF), Flt-3/Flk-2 ligand
(FL), and thrombopoietin (TPO) for 14 days. We then transferred
the cells to hTERT stroma and cultured for another 14 days with
fresh medium containing interleukin-11 (IL-11) in addition to the
original cytokine cocktail. Subsequently, we cultured the cells
in a liquid culture medium containing SCF, FL, TPO, and IL-11 for
another 5 days to recover PLT fractions from the supernatant, which
were then gel-filtered to purify the PLTs. The calculated yield
of PLTs from 1.0 unit of CB (5 x 10(6) CD34(+) cells) was 1.26 x
10(11)-1.68 x 10(11) PLTs. These numbers of PLTs are equivalent
to 2.5-3.4 units of random donor-derived PLTs or 2/5-6/10 of single-apheresis
PLTs. The CB-derived PLTs exhibited features quite similar to those
from peripheral blood in morphology, as revealed by electron micrographs,
and in function, as revealed by fibrinogen/ADP aggregation, with
the appearance of P-selectin and activated glycoprotein IIb-IIIa
antigens. Thus, this culture system may be applicable for large-scale
generation of PLTs for future clinical use.
Functional Neuronal Differentiation of Bone
Marrow-Derived Mesenchymal Stem Cells
Philippe Tropel et al., Stem Cells. 2006 Dec;24(12):2868-76. Epub
2006 Aug 10.
Abstract: Recent results have shown the ability
of bone marrow cells to migrate in the brain and to acquire neuronal
or glial characteristics. In vitro, bone marrow-derived MSCs can
be induced by chemical compounds to express markers of these lineages.
In an effort to set up a mouse model of such differentiation, we
addressed the neuronal potentiality of mouse MSCs (mMSCs) that we
recently purified. These cells expressed nestin, a specific marker
of neural progenitors. Under differentiating conditions, mMSCs display
a distinct neuronal shape and express neuronal markers NF-L (neurofilament-light,
or neurofilament 70 kDa) and class III beta-tubulin. Moreover, differentiated
mMSCs acquire neuron-like functions characterized by a cytosolic
calcium rise in response to various specific neuronal activators.
Finally, we further demonstrated for the first time that clonal
mMSCs and their progeny are competent to differentiate along the
neuronal pathway, demonstrating that these bone marrow-derived stem
cells share characteristics of widely multipotent stem cells unrestricted
to mesenchymal differentiation pathways.
Bone Marrow Transplantation Attenuates the
Myopathic Phenotype of a Muscular Mouse Model of Spinal Muscular
Nouzha Salah-Mohellibi et al., Stem Cells. 2006 Dec;24(12):2723-32.
Epub 2006 Aug 3.
Abstract: Bone marrow (BM) transplantation was
performed on a muscular mouse model of spinal muscular atrophy that
had been created by mutating the survival of motor neuron gene (Smn)
in myofibers only. This model is characterized by a severe myopathy
and progressive loss of muscle fibers leading to paralysis. Transplantation
of wild-type BM cells following irradiation at a low dose (6 Gy)
improved motor capacity (+85%). This correlated with a normalization
of myofiber number associated with a higher number of regenerating
myofibers (1.6-fold increase) and an activation of CD34 and Pax7
satellite cells. However, BM cells had a very limited capacity to
replace or fuse to mutant myofibers (2%). These data suggest that
BM transplantation was able to attenuate the myopathic phenotype
through an improvement of skeletal muscle regeneration of recipient
mutant mice, a process likely mediated by a biological activity
of BM-derived cells. This hypothesis was further supported by the
capacity of muscle protein extracts from transplanted mutant mice
to promote myoblast proliferation in vitro (1.6-fold increase).
In addition, a tremendous upregulation of hepatocyte growth factor
(HGF), which activates quiescent satellite cells, was found in skeletal
muscle of transplanted mutants compared with nontransplanted mutants.
Eventually, thanks to the Cre-loxP system, we show that BM-derived
muscle cells were strong candidates harboring this biological activity.
Taken together, our data suggest that a biological activity is likely
involved in muscle regeneration improvement mediated by BM transplantation.
HGF may represent an attractive paracrine mechanism to support this
Increased generation of neuronal progenitors
after ischemic injury in the aged adult human forebrain.
Macas J, et al., J Neurosci. 2006 Dec 13;26(50):13114-9.
Abstract: The adult human brain retains the capacity
to generate new neurons in the hippocampal formation (Eriksson et
al., 1998) and neuronal progenitor cells (NPCs) in the forebrain
(Bernier et al., 2000), but to what extent it is capable of reacting
to injuries, such as ischemia, is not known. We analyzed postmortem
tissue from normal and pathological human brain tissue (n = 54)
to study the cellular response to ischemic injury in the forebrain.
We observed that cells expressing the NPC marker polysialylated
neural adhesion cell molecule (PSA-NCAM) are continuously generated
in the adult human subventricular zone (SVZ) and migrate along the
olfactory tracts. These cells were not organized in migrating chains
as in the adult rodent rostral migratory stream, and their number
was lower in the olfactory tracts of brains from old (56-81 years
of age) compared with young (29 + 36 years of age) individuals.
Moreover, we show that in brains of patients of advanced age (60-87
years of age), ischemia led to an elevated number of Ki-67-positive
cells in the ipsilateral SVZ without concomitant apoptotic cell
death. Additionally, ischemia led to an increased number of PSA-NCAM-positive
NPCs close to the lateral ventricular walls, compared with brains
of comparable age without obvious neuropathologic changes. These
results suggest that the adult human brain retains a capacity to
respond to ischemic injuries and that this capacity is maintained
even in old age.
A neurovascular niche for neurogenesis after
Ohab JJ, et al., J Neurosci. 2006 Dec 13;26(50):13007-16.
Abstract: Stroke causes cell death but also birth
and migration of new neurons within sites of ischemic damage. The
cellular environment that induces neuronal regeneration and migration
after stroke has not been defined. We have used a model of long-distance
migration of newly born neurons from the subventricular zone to
cortex after stroke to define the cellular cues that induce neuronal
regeneration after CNS injury. Mitotic, genetic, and viral labeling
and chemokine/growth factor gain- and loss-of-function studies show
that stroke induces neurogenesis from a GFAP-expressing progenitor
cell in the subventricular zone and migration of newly born neurons
into a unique neurovascular niche in peri-infarct cortex. Within
this neurovascular niche, newly born, immature neurons closely associate
with the remodeling vasculature. Neurogenesis and angiogenesis are
causally linked through vascular production of stromal-derived factor
1 (SDF1) and angiopoietin 1 (Ang1). Furthermore, SDF1 and Ang1 promote
post-stroke neuroblast migration and behavioral recovery. These
experiments define a novel brain environment for neuronal regeneration
after stroke and identify molecular mechanisms that are shared between
angiogenesis and neurogenesis during functional recovery from brain
Spontaneous Fusion and Non-clonal Growth of
Adult Neural Stem Cells
Sebastian Jessberger et al., Stem Cells, published online December
21, 2006; doi:10.1634/stemcells.2006-0620.
Abstract: Multipotent neural stem cells (NSCs) can be isolated
from various regions of the adult brain and propagated in vitro.
Recent reports have suggested spontaneous fusion events among NSCs
when grown as free-floating neurospheres that may affect the genetic
composition of NSC cultures. We used adult NSCs expressing either
red fluorescent protein (RFP) or green fluorescent protein (GFP)
to analyze the fusion frequency of rat and mouse NSCs. Fluorescence
activated cell sorting (FACS) revealed, that under proliferating
conditions approximately 0.2% of rat and mouse NSCs coexpressed
RFP and GFP, irrespective of whether the cells were grown as neurospheres
(mouse NSCs) or as attached monolayers (rat and mouse NSCs). Fused
cells did not proliferate and could not be propagated, suggesting
that aberrantly fused cells are not viable. Furthermore, we found
that neither neurospheres nor monolayers grew clonally, as even
very low-density cultures had spheres containing both GFP- and RFP-expressing
cells and monolayer patches with GFP- and RFP-expressing cells in
close proximity. The non-clonal growth between distinct NSC populations
strongly suggests the use of careful and precise culture conditions,
such as single cell assays, to characterize potency and growth of
NSCs in vitro.
Designer Self-Assembling Peptide Nanofiber
Scaffolds for Adult Mouse Neural Stem Cell 3-Dimensional Cultures
Fabrizio Gelain et al., PLoS ONE 1. e119., i:10.1371/journal.pone.0000119,
Abstract: Biomedical researchers have become increasingly
aware of the limitations of conventional 2-dimensional tissue cell
culture systems, including coated Petri dishes, multi-well plates
and slides, to fully address many critical issues in cell biology,
cancer biology and neurobiology, such as the 3-D microenvironment,
3-D gradient diffusion, 3-D cell migration and 3-D cell-cell contact
interactions. In order to fully understand how cells behave in the
3-D body, it is important to develop a well-controlled 3-D cell
culture system where every single ingredient is known. Here we report
the development of a 3-D cell culture system using a designer peptide
nanofiber scaffold with mouse adult neural stem cells. We attached
several functional motifs, including cell adhesion, differentiation
and bone marrow homing motifs, to a self-assembling peptide RADA16
(Ac-RADARADARADARADA-COHN2). These functionalized peptides undergo
self-assembly into a nanofiber structure similar to Matrigel. During
cell culture, the cells were fully embedded in the 3-D environment
of the scaffold. Two of the peptide scaffolds containing bone marrow
homing motifs significantly enhanced the neural cell survival without
extra soluble growth and neurotrophic factors to the routine cell
culture media. In these designer scaffolds, the cell populations
with b-Tubulin+, GFAP+ and Nestin+ markers are similar to those
found in cell populations cultured on Matrigel. The gene expression
profiling array experiments showed selective gene expression, possibly
involved in neural stem cell adhesion and differentiation. Because
the synthetic peptides are intrinsically pure and a number of desired
function cellular motifs are easy to incorporate, these designer
peptide nanofiber scaffolds provide a promising controlled 3-D culture
system for diverse tissue cells, and are useful as well for general
molecular and cell biology.
Mesenchymal Stem Cell-Mediated Functional
Tooth Regeneration in Swine
Wataru Sonoyama et al., PLoS ONE 2006 Dec 20;1:e79.
Abstract: Mesenchymal stem cell-mediated tissue
regeneration is a promising approach for regenerative medicine for
a wide range of applications. Here we report a new population of
stem cells isolated from the root apical papilla of human teeth
(SCAP, stem cells from apical papilla). Using a minipig model, we
transplanted both human SCAP and periodontal ligament stem cells
(PDLSCs) to generate a root/periodontal complex capable of supporting
a porcelain crown, resulting in normal tooth function. This work
integrates a stem cell-mediated tissue regeneration strategy, engineered
materials for structure, and current dental crown technologies.
This hybridized tissue engineering approach led to recovery of tooth
strength and appearance.
Transplantation of Mesenchymal Stem Cells
is an Optimal Approach for Plastic Surgery
Dianji Fang et al., Stem Cells, published online December 14,
Abstract: Mesenchymal stem cells (MSCs) are able
to differentiate into a variety of cell types, offering promising
approaches for stem-cell-mediated tissue regeneration. Here we explored
the potential of utilizing MSCs to reconstruct orofacial tissue,
thereby, altering the orofacial appearance. We demonstrated that
bone marrow MSCs were capable of generating bone structures and
bone-associated marrow elements on the surfaces of the orofacial
bone. This resulted in significant re-contouring of the facial appearance
in mouse and swine. Notably, the newly formed bone/marrow tissues
integrated with the surfaces of the recipient bones and re-established
a functional bone marrow organ-like system. These data suggested
that MSC-mediated tissue regeneration led to a body structure extension,
with the re-establishment of all functional components necessary
for maintaining the bone/marrow organ. In addition, we found that
the subcutaneous transplantation of another population of MSCs,
the human periodontal ligament stem cells (PDLSCs) could form substantial
amounts of collagen fibers and improve facial wrinkles in mouse.
By contrast, bone marrow MSCs failed to survive at 8 weeks post-transplantation
under the conditions used for the PDLSC transplantation. This study
suggested that the mutual interactions between donor MSCs and recipient
microenvironment determine long-term outcome of the functional tissue
Mobilizes Bone Marrow Stem Cells in Patients With Subacute Ischemic
Stroke The Stem Cell Trial of Recovery EnhanceMent After Stroke
(STEMS) Pilot Randomized, Controlled Trial (ISRCTN 16784092)
Nikola Sprigg et al., Stroke. 2006 Dec; 37(12):2979-83. Epub 2006
Background and Purpose: Loss of motor function
is common after stroke and leads to significant chronic disability.
Stem cells are capable of self-renewal and of differentiating into
multiple cell types, including neurones, glia, and vascular cells.
We assessed the safety of granulocyte-colony-stimulating factor
(G-CSF) after stroke and its effect on circulating CD34+ stem cells.
METHODS: We performed a 2-center, dose-escalation, double-blind,
randomized, placebo-controlled pilot trial (ISRCTN 16784092) of
G-CSF (6 blocks of 1 to 10 microg/kg SC, 1 or 5 daily doses) in
36 patients with recent ischemic stroke. Circulating CD34+ stem
cells were measured by flow cytometry; blood counts and measures
of safety and functional outcome were also monitored. All measures
were made blinded to treatment.
RESULTS: Thirty-six patients, whose mean+/-SD age was 76+/-8 years
and of whom 50% were male, were recruited. G-CSF (5 days of 10 microg/kg)
increased CD34+ count in a dose-dependent manner, from 2.5 to 37.7
at day 5 (area under curve, P=0.005). A dose-dependent rise in white
cell count (P<0.001) was also seen. There was no difference between
treatment groups in the number of patients with serious adverse
events: G-CSF, 7/24 (29%) versus placebo 3/12 (25%), or in their
dependence (modified Rankin Scale, median 4, interquartile range,
3 to 5) at 90 days.
CONCLUSIONS: G-CSF is effective at mobilizing bone marrow CD34+
stem cells in patients with recent ischemic stroke. Administration
is feasible and appears to be safe and well tolerated. The fate
of mobilized cells and their effect on functional outcome remain
to be determined.
Successful treatment of AL amyloidosis with
high-dose melphalan and autologous stem cell transplantation in
patients over age 65
David C. Seldin et al., Blood. 2006 Dec 1;108(12):3945-7. Epub
2006 Aug 22.
Abstract: Recently, protocols using high-dose melphalan
chemotherapy and autologous peripheral blood stem cell transplantation
(HDM/SCT) have been developed for the treatment of patients with
immunoglobulin light chain (AL) amyloidosis. Although peritransplantation
mortality is greater than for other hematologic diseases, treatment
leads to durable hematologic complete responses, improvements in
organ function and quality of life, and extended survival in a substantial
proportion of patients. To determine whether this treatment can
be applied to older patients, we have analyzed HDM/SCT treatment
outcomes for 65 patients (aged 65 years or older) with AL amyloidosis
compared with outcomes for 280 younger patients. For patients over
age 65 years who meet the same eligibility criteria as younger patients,
toxicity, hematologic remission rate, and survival were not significantly
different from those observed in younger patients, indicating that
older patients should not be excluded a priori from consideration
for HDM/SCT treatment.
Isolation of an adult blood-derived progenitor
cell population capable of differentiation into angiogenic, myocardial
and neural lineages
Yael Porat et al., British Journal of Haematology. 2006 Dec;135(5):703-14.
Abstract: Blood-derived adult stem cells were previously
considered impractical for therapeutic use because of their small
numbers. This report describes the isolation of a novel human cell
population derived from the peripheral blood, termed synergetic
cell population (SCP), and defined by the expression of CD31Bright,
CD34+, CD45)/Dim and CD34Bright, but not lineage-specific features.
The SCP was capable of differentiating into a variety of cell lineages
upon exposure to defined culture conditions. The resulting cells
exhibited morphological, immunocytochemical and functional characteristics
of angiogenic, neural or myocardial lineages. Angiogenic cell precursors
(ACPs) expressed CD34, CD133, KDR, Tie-2, CD144, von Willebrand
factor, CD31Bright, concomitant binding of Ulex-Lectin and uptake
of acetylated low density lipoprotein (Ac-LDL), secreted interleukin-8,
vascular endothelial growth factor and angiogenin and formed tube-like
structures in vitro. The majority of CD31Bright ACP cells demonstrated
Ac-LDL uptake. Neural cell precursors (NCPs) expressed the neuronal
markers Nestin, bIII-Tubulin, and Neu-N, the glial markers GFAP
and O4, and responded to neurotransmitter stimulation. Myocardial
cell precursors (MCPs) expressed Desmin, cardiac Troponin and Connexin
43. In conclusion, the simple and rapid method of SCP generation
and the resulting considerable quantities of lineage-specific precursor
cells makes it a potential source of autologous treatment for a
variety of diseases.
Myeloid progenitors differentiate intomicroglia and promote
vascular repair in a model of ischemic retinopathy
Matthew R. Ritter et al., J. Clin. Invest. 2006 Dec;116(12):3266-76.
Epub 2006 Nov 16.
Abstract: Vision loss associated with ischemic
diseases such as retinopathy of prematurity and diabetic retinopathy
are often due to retinal neovascularization. While significant progress
has been made in the development of compounds useful for the treatment
of abnormal vascular permeability and proliferation, such therapies
do not address the underlying hypoxia that stimulates the observed
vascular growth. Using a model of oxygen-induced retinopathy, we
demonstrate that a population of adult BM-derived myeloid progenitor
cells migrated to avascular regions of the retina, differentiated
into microglia, and facilitated normalization of the vasculature.
Myeloid-specific hypoxia-inducible factor 1alpha (HIF-1alpha) expression
was required for this function, and we also demonstrate that endogenous
microglia participated in retinal vascularization. These findings
suggest what we believe to be a novel therapeutic approach for the
treatment of ischemic retinopathies that promotes vascular repair
rather than destruction.
Cytokine-induced differentiation of multipotent adult
progenitor cells into functional smooth muscle cells
J. Ross et al.
J. Clin. Invest. 2006 Dec;116(12):3139-49. Epub 2006 Nov 9.
Abstract: Smooth muscle formation and function are critical in development
and postnatal life. Hence, studies aimed at better understanding
SMC differentiation are of great importance. Here, we report that
multipotent adult progenitor cells (MAPCs) isolated from rat, murine,
porcine, and human bone marrow demonstrate the potential to differentiate
into cells with an SMC-like phenotype and function. TGF-beta1 alone
or combined with PDGF-BB in serum-free medium induces a temporally
correct expression of transcripts and proteins consistent with smooth
muscle development. Furthermore, SMCs derived from MAPCs (MAPC-SMCs)
demonstrated functional L-type calcium channels. MAPC-SMCs entrapped
in fibrin vascular molds became circumferentially aligned and generated
force in response to KCl, the L-type channel opener FPL64176, or
the SMC agonists 5-HT and ET-1, and exhibited complete relaxation
in response to the Rho-kinase inhibitor Y-27632. Cyclic distention
(5% circumferential strain) for 3 weeks increased responses by 2-
to 3-fold, consistent with what occurred in neonatal SMCs. These
results provide evidence that MAPC-SMCs are phenotypically and functionally
similar to neonatal SMCs and that the in vitro MAPC-SMC differentiation
system may be an ideal model for the study of SMC development. Moreover,
MAPC-SMCs may lend themselves to tissue engineering applications.
Human stem/progenitor cells from bone marrow promote
neurogenesis of endogenous neural stem cells in the hippocampus
Munoz JR, et al.
Proc Natl Acad Sci U S A. 2005 Dec 13;102(50):18171-6. Epub 2005
Abstract: Stem/progenitor cells from bone marrow and other sources
have been shown to repair injured tissues by differentiating into
tissue-specific phenotypes, by secreting chemokines, and, in part,
by cell fusion. Here we prepared the stem/progenitor cells from
human bone marrow (MSCs) and implanted athem into the dentate gyrus
of the hippocampus of immunodeficient mice. The implanted human
MSCs markedly increased the proliferation of endogenous neural stem
cells that expressed the stem cell marker Sox2. Labeling of the
mice with BrdUrd demonstrated that, 7 days after implantation of
the human MSCs, BrdUrd-labeled endogenous cells migrated throughout
the dorsal hippocampus (positive for doublecortin) and expressed
markers for astrocytes and for neural or oligodendrocyte progenitors.
Subpopulations of BrdUrd-labeled cells exhibited short cytoplasmic
processes immunoreactive for nerve growth factor and VEGF. By 30
days after implantation, the newly generated cells expressed markers
for more mature neurons and astrocytes. Also, subpopulations of
BrdUrd-labeled cells exhibited elaborate processes immunoreactive
for ciliary neurotrophic factor, neurotrophin-4/5, nerve growth
factor, or VEGF. Therefore, implantation of human MSCs stimulated
proliferation, migration, and differentiation of the endogenous
neural stem cells that survived as differentiated neural cells.
The results provide a paradigm to explain recent observations in
which MSCs or related stem/progenitor cells were found to produce
improvements in disease models even though a limited number of the
Autologous serum-derived cultivated oral epithelial transplants
for severe ocular surface disease.
Ang LP, et al.
Arch Ophthalmol. 2006 Nov;124(11):1543-51.
OBJECTIVE: To evaluate the use of autologous serum (AS)-derived
cultivated oral epithelial transplants for the treatment of severe
ocular surface disease.
METHODS: We used AS from 10 patients with severe ocular surface
disease and total limbal stem cell deficiency to develop autologous
cultivated oral epithelial equivalents. These were compared with
epithelial equivalents derived from conventional fetal bovine serum-supplemented
medium. Surgery involved removal of the corneal pannus and surrounding
diseased tissue and transplantation of the AS-derived epithelial
equivalents. The oral equivalents were analyzed by review of histologic
and immunohistochemical findings.
RESULTS: Oral epithelial sheets cultivated in AS- and fetal bovine
serum-supplemented media were similar in morphology, and both formed
basement membrane assembly proteins important for maintaining graft
integrity. Complete corneal epithelialization was achieved within
2 to 5 days postoperatively. The ocular surface remained stable
without major complications in all eyes during a mean +/- SD follow-up
of 12.6 +/- 3.9 months. The visual acuity improved by more than
2 lines in 9 of 10 eyes, with transplanted oral epithelium surviving
up to 19 months.
CONCLUSION: The successful use of an AS-derived oral epithelial
equivalent to treat severe ocular surface disease represents an
important advance in the pursuit of completely autologous xenobiotic-free
bioengineered ocular equivalents for clinical transplantation.
Tracking Neural Stem Cells in Patients with Brain
Jianhong Zhu, et al.
N Engl J Med. 2006 Nov 30;355(22):2376-8.
To the Editor: Regeneration of damaged brain tissue with neural
stem cells is a promising strategy for reversing neurologic deficits.1
Superparamagnetic iron oxide nanoparticles have been used to label
and track dendritic cells in the experimental treatment of melanoma2
and in experiments in animals. We report the feasibility of labeling
neural stem cells from humans (two patients for whom written informed
consent was provided by next of kin) with superparamagnetic iron
oxide nanoparticles and tracking them with the use of magnetic resonance
Antibody Targeting of Stem Cells to Infarcted Myocardium
Randall J. Lee et al.
Stem Cells, published online November 30, 2006; doi:10.1634/stemcells.2005-0602.
Abstract: Hematopoietic stem cell therapy for myocardial repair
is limited by the number of stem cells that migrate to, engraft
in and proliferate at sites of injured myocardium. To alleviate
this limitation, we studied whether a strategy using a bispecific
antibody could target human stem cells specifically to injuredmyocardium
and preserve myocardial function. Using a xenogeneic rat model whereby
ischemic injury was induced by transient ligation of the left anterior
descending artery (LAD), we determined the ability of a bispecific
antibody to target human CD34+ cells to specific antigens expressed
in ischemic injured myocardium. A bispecific antibody comprised
of an anti-CD45 antibody recognizing the common leukocyte antigen
found on hematopoietic stem cells (HSC) and an antibody recognizing
myosin light chain, an organ-specific injury antigen expressed by
infarcted myocardium was prepared by chemical conjugation. CD34+
cells armed and unarmed with this BiAb were injected intravenously
in rats 2 days post-myocardial injury. Immunohistochemistry studies
showed that the armed CD34+ cells specifically localized to the
infracted region of the heart, co-localized with troponin T stained
cells and co-localized with vascular structures. Compared to unarmed
CD34+ cells, the bispecific antibody improved delivery of the stem
cells to injured myocardium and such targeted delivery was correlated
with improved myocardial function five weeksfollowing infarction
(p<0.01). Bispecific antibody targeting offers a unique means
to improve the delivery of stem cells to facilitate organ repair
and a tool to study stem cell biology.
Stem Cells, Myocardial Regeneration and Methodological
Piero Anversa et al.
Stem Cells, published online November 30, 2006; doi:10.1634/stemcells.2006-0623.
Abstract: This review discusses the controversy that has permeated
the field of myocardial regeneration in the last three decades.
The notion of the heart as a terminally differentiated postmitotic
organ has been so strong that observations promoting the opposite
paradigm have been questioned technically and conceptually. The
possibility of misinterpretation of results collected with cellular,
molecular, and morphological methodologies has been the prevailing
position in the scientific community. Myocardial regeneration mediated
by activation of endogenous progenitor cells or by engraftment and
differentiation of primitive cells from the bone marrow has been
rejected strongly in an attempt to defend an unrealistic view of
the heart. This article provides evidence in support of the notion
that the heart is an organ regulated by a stem cell compartment
responsible for cardiac homeostasis and repair.
Improved clinical outcome after intracoronary administration
of bone-marrow-derived progenitor cells in acute myocardial infarction:
final 1-year results of the REPAIR-AMI trial.
Schachinger V, et al.
Eur Heart J. 2006 Dec;27(23):2775-83. Epub 2006 Nov 10.
AIMS: To investigate the clinical outcome after intracoronary administration
of autologous progenitor cells in patients with acute myocardial
METHODS AND RESULTS: Using a double-blind, placebo-controlled multicentre
trial design, we randomized 204 patients with successfully reperfused
AMI to receive intracoronary infusion of bone-marrow-derived progenitor
cells (BMCs) or placebo medium into the infarct artery 3-7 days
after successful infarct reperfusion therapy. At 12 months, the
pre-specified cumulative endpoint of death, myocardial infarction,
or necessity for revascularization was significantly reduced in
the BMC group compared with placebo (P=0.009). Likewise, the combined
endpoint death, recurrence of myocardial infarction, and rehospitalization
for heart failure was significantly (P=0.006) reduced in patients
receiving intracoronary BMC administration. Intracoronary administration
of BMC remained a significant predictor of a favourable clinical
outcome by Cox regression analysis, adjusting for classical predictors
of poor outcome after AMI.
CONCLUSION: Intracoronary administration of BMCs is associated with
a significant reduction of the occurrence of major adverse cardiovascular
events after AMI. Large-scale studies are warranted to confirm the
effects of BMC administration on mortality and morbidity in patients
In Vitro and in Vivo Arterial Differentiation of Human
Multipotent Adult Progenitor Cells
Xabier L. Aranguren et al.
Blood First Edition Paper. prepublished online November 7, 2006;
Abstract: Many stem cell types have been shown to differentiate
into endothelial cells (ECs), however, their specification to arterial
or venous endothelium remains unexplored. We tested whether a specific
arterial or venous EC fate could be induced in human Multipotent
Adult Progenitor Cells (hMAPCs) and AC133+ cells (hAC133+). In vitro,
in the presence of VEGF165, hAC133+ cells only adopted a venous
and microvascular EC phenotype, while hMAPCs differentiated into
both arterial and venous ECs, possibly because hMAPCs expressed
significantly more sonic hedgehog (Shh) and its receptors, as well
as Notch 1 and 3 receptors and some of their ligands. Accordingly,
blocking either of those pathways attenuated in vitro arterial EC
differentiation from hMAPCs. Complementarily, stimulating these
pathways by addition of Delta-like 4 (Dll-4), a Notch ligand, and
Shh to VEGF165 further boosted arterial differentiation in hMAPCs
both in vitro and in an in vivo matrigel model. These results represent
the first demonstration of adult stem cells with the potential to
be differentiated into different types of ECs in vitro and in vivo
and provide a useful human model to study arterio-venous specification.
Therapeutic strategies for Parkinson.s disease based
on the modulation of adult neurogenesis
Martine Geraerts et al.
Stem Cells, published online November 2, 2006; doi:10.1634/stemcells.2006-0364.
Abstract: Parkinson.s disease (PD) is a progressive neurodegenerative
disorder, affecting millions of people world-wide. To date, treatment
strategies are mainly symptomatic and aimed at increasing dopamine
levels in the degenerating nigrostriatal system. Hope rests upon
the development of effective neurorestorative or neuroregenerative
therapies based on gene and stem cell therapy or a combination of
both. The results of experimental therapies based on transplanting
exogenous dopamine-rich fetal cells or growth factor (GDNF) overexpression
into the brain of Parkinson.s disease patients encourage future
cell- and gene-based strategies. The endogenous neural stem cells
of the adult brain provide an alternative and attractive cell source
for neuroregeneration. Prior to designing endogenous stem cell therapies,
one has to investigate the possible impact of PD on adult neuronal
stem cell pools and their neurogenic potential. We review the experimental
data obtained in animal models or based on analysis of patients.
brain prior to describing different treatment strategies. Strategies
aiming to enhance neuronal stem cell proliferation and/or differentiation
in the striatum or the substantia nigra will have to be compared
in animal models and selected prior to clinical studies.
Mesoangioblast stem cells ameliorate muscle function
in dystrophic dogs.
Sampaolesi M et al.
Nature. 2006 Nov 30;444(7119):574-9. Epub 2006 Nov 15.
Abstract: Duchenne muscular dystrophy remains an untreatable genetic
disease that severely limits motility and life expectancy in affected
children. The only animal model specifically reproducing the alterations
in the dystrophin gene and the full spectrum of human pathology
is the golden retriever dog model. Affected animals present a single
mutation in intron 6, resulting in complete absence of the dystrophin
protein, and early and severe muscle degeneration with nearly complete
loss of motility and walking ability. Death usually occurs at about
1 year of age as a result of failure of respiratory muscles. Here
we report that intra-arterial delivery of wild-type canine mesoangioblasts
(vessel-associated stem cells) results in an extensive recovery
of dystrophin expression, normal muscle morphology and function
(confirmed by measurement of contraction force on single fibres).
The outcome is a remarkable clinical amelioration and preservation
of active motility. These data qualify mesoangioblasts as candidates
for future stem cell therapy for Duchenne patients.
Transplantation of human neural stem cells exerts
neuroprotection in a rat model of Parkinson's disease.
Yasuhara T et al.
J Neurosci. 2006 Nov 29;26(48):12497-511.
Abstract: Neural stem cells (NSCs) possess high potencies of self-renewal
and neuronal differentiation. We explored here whether transplantation
of human NSCs cloned by v-myc gene transfer, HB1.F3 cells, is a
feasible therapeutic option for Parkinson's disease. In vivo, green
fluorescent protein-labeled HB1.F3 cells (200,000 viable cells in
3 microl of PBS) when stereotaxically transplanted (same-day lesion-transplant
paradigm) into the 6-hydroxydopamine-lesioned striatum of rats significantly
ameliorated parkinsonian behavioral symptoms compared with controls
(vehicle, single bolus, or continuous minipump infusion of trophic
factor, or killed cell grafts). Such graft-derived functional effects
were accompanied by preservation of tyrosine hydroxylase (TH) immunoreactivity
along the nigrostriatal pathway. Grafted HB1.F3 cells survived in
the lesioned brain with some labeled with neuronal marker mitogen-activated
protein 2 and decorated with synaptophysin-positive terminals. Furthermore,
endogenous neurogenesis was activated in the subventricular zone
of transplanted rats. To further explore the neuroprotective mechanisms
underlying HB1.F3 cell transplantation, we performed cell culture
studies and found that a modest number of HB1.F3 cells were TH and
dopamine and cAMP-regulated phosphoprotein 32 positive, although
most cells were nestin positive, suggesting a mixed population of
mature and immature cells. Administration of the HB1.F3 supernatant
to human derived dopaminergic SH-SY5Y cells and fetal rat ventral
mesencephalic dopaminergic neurons protected against 6-hydroxydopamine
neurotoxicity by suppressing apoptosis through Bcl-2 upregulation,
which was blocked by anti-stem cell factor antibody alone, the phosphatidylinositol
3-kinase/Akt inhibitor LY294002 [2-(4-morpholinyl)-8-phenyl-1(4H)-benzopyran-4-one]
alone, or a combination of both. These results suggest that HB1.F3
cell transplantation exerts neuroprotective effects against dopaminergic
depletion in vitro and in vivo because of trophic factor secretion
and neuronal differentiation.
Adipose Tissue-Derived Mesenchymal Stem Cells Have
In Vivo Immunosuppressive Properties Applicable for the Control
of the Graft-Versus-Host Disease
Rosa Yanez et al.
Stem Cells. 2006 Nov;24(11):2582-91. Epub 2006 Jul 27.
Abstract: Previous studies have shown the relevance of bone marrow-
derived MSCs (BM-MSCs) in controlling graft-versus- host disease
(GVHD) after allogeneic transplantation. Since adipose tissue-derived
MSCs (Ad-MSCs) may constitute a good alternative to BM-MSCs, we
have expanded MSCs derived from human adipose tissue (hAd-MSCs)
and mouse adipose tissue (mAd-MSCs), investigated the immunoregulatory
properties of these cells, and evaluated their capacity to control
GVHD in mice. The phenotype and immunoregulatory properties of expanded
hAd-MSCs were similar to those of human BM-MSCs. Moreover, hAd-MSCs
inhibited the proliferation and cytokine secretion of human primary
T cells in response to mitogens and allogeneic T cells. Similarly,
ex vivo expanded mAd-MSCs had an equivalent immunophenotype and
exerted immunoregulatory properties similar to those of hAd-MSCs.
Moreover, the infusion of mAd-MSCs in mice transplanted with haploidentical
hematopoietic grafts controlled the lethal GVHD that occurred in
control recipient mice. These findings constitute the first experimental
proof that Ad-MSCs can efficiently control the GVHD associated with
allogeneic hematopoietic transplantation, opening new perspectives
for the clinical use of Ad-MSCs.
Side Population Cells Isolated from Porcine Dental
Pulp Tissue with Self-Renewal and Multipotency for Dentinogenesis,
Chondrogenesis, Adipogenesis, and Neurogenesis
Koichiro Iohara et al.
Stem Cells. 2006 Nov;24(11):2493-503. Epub 2006 Jul 27.
Abstract: Dental pulp has the potential to form dentin as a regenerative
response to caries. This regeneration is mediated by stem/progenitor
cells. Thus, stem cell therapy might be of potential utility in
induction of reparative dentin. We isolated side population (SP)
cells from dental pulp based on the exclusion of the DNA binding
dye Hoechst 33342 by flow cytometry and compared its self-renewal
capacities and multipotency with non-SP cells and primary pulp cells.
The cumulative cell number of the SP cells was greater than the
non-SP cells and primary pulp cells. Bmi1 was continuously expressed
in SP cells, suggesting longer proliferative lifespan and self-renewal
capacity of SP cells. Next, the maintenance of the multilineage
differentiation potential of pulp SP cells was investigated. Expression
of type II collagen and aggrecan confirmed chondrogenic conversion
(30%) of SP cells. SP cells expressed peroxisome proliferator-activated
receptor _ and adaptor protein 2, showing adipogenic conversion.
Expression of mRNA and proteins of neurofilament and neuromodulin
confirmed neurogenic conversion (90%). These results demonstrate
that pulp SP cells maintain multilineage differentiation potential.
We further examined whether bone morphogenetic protein 2 (BMP2)
could induce differentiation of pulp SP cells into odontoblasts.
BMP2 stimulated the expression of dentin sialophosphoprotein (Dspp)
and enamelysin in three-dimensional pellet cultures. Autogenous
transplantation of the Bmp2-supplemented SP cells on the amputated
pulp stimulated the reparative dentin formation. Thus, adult pulp
contains SP cells, which are enriched for stem cell properties and
useful for cell therapy with BMP2 for dentin regeneration.
Bone Marrow-Derived Cells Contribute to Podocyte Regeneration
and Amelioration of Renal Disease in a Mouse Model of Alport Syndrome
Evangelia I. Prodromidi et al.
Stem Cells. 2006 Nov;24(11):2448-55. Epub 2006 Jul 27.
Abstract: In a model of autosomally recessive Alport syndrome, mice
that lack the alpha3 chain of collagen IV (Col4alpha3(-/-)) develop
progressive glomerular damage leading to renal failure. The proposed
mechanism is that podocytes fail to synthesize normal glomerular
basement membrane, so the collagen IV network is unstable and easily
degraded. We used this model to study whether bone marrow (BM) transplantation
can rectify this podocyte defect by correcting the deficiency in
Col4alpha3. Female C57BL/6 Col4alpha3(-/-) (-/-) mice were transplanted
with whole BM from male wild-type (+/+) mice. Control female -/-
mice received BM from male -/- littermates. Serum urea and creatinine
levels were significantly lower in recipients of +/+ BM compared
with those of -/- BM 20 weeks post-transplant. Glomerular scarring
and interstitial fibrosis were also significantly decreased. Donor-derived
cells were detected by in situ hybridization (ISH) for the Y chromosome,
and fluorescence and confocal microscopy indicated that some showed
an apparent podocyte phenotype in mice transplanted with +/+ BM.
Glomeruli of these mice showed small foci of staining for alpha3(IV)
protein by immunofluorescence. alpha3(IV) mRNA was detectable by
reverse transcription-polymerase chain reaction and ISH in some
mice transplanted with +/+ BM but not -/- BM. However, a single
injection of mesenchymal stem cells from +/+ mice to irradiated
-/- recipients did not improve renal disease. Our data show that
improved renal function in Col4alpha3(-/-) mice results from BM
transplantation from wild-type donors, and the mechanism by which
this occurs may in part involve generation of podocytes without
the gene defect.
Leukemia inhibitory factor promotes neural stem cell
self-renewal in the adult brain.
Bauer S, Patterson PH.
J Neurosci. 2006 Nov 15;26(46):12089-99.
Abstract: Although neural stem cells (NSCs) persist in various areas
of the adult brain, their contribution to brain repair after injury
is very limited. Treatment with exogenous growth factors can mitigate
this limitation, suggesting that the brain environment is normally
deficient in permissive cues and that it may be possible to stimulate
the latent regenerative potential of endogenous progenitors with
appropriate signals. We analyzed the effects of overexpressing the
cytokine leukemia inhibitory factor (LIF) on adult neurogenesis
in the normal brain. We found that LIF reduces neurogenesis in the
olfactory bulb and subventricular zone by acting directly on NSCs.
LIF appears to promote NSC self-renewal, preventing the emergence
of more differentiated cell types. This ultimately leads to an expansion
of the NSC pool. Our results have implications for the development
of therapeutic strategies for brain repair and suggest that LIF
may be useful, in combination with other factors, in promoting regeneration
in the adult brain.
Thymosin beta4 induces adult epicardial progenitor
mobilization and neovascularization.
Smart N, et al.
Nature. 2006 Nov 15; [Epub ahead of print]
Abstract: Cardiac failure has a principal underlying aetiology of
ischaemic damage arising from vascular insufficiency. Molecules
that regulate collateral growth in the ischaemic heart also regulate
coronary vasculature formation during embryogenesis. Here we identify
thymosin beta4 (Tbeta4) as essential for all aspects of coronary
vessel development in mice, and demonstrate that Tbeta4 stimulates
significant outgrowth from quiescent adult epicardial explants,
restoring pluripotency and triggering differentiation of fibroblasts,
smooth muscle cells and endothelial cells. Tbeta4 knockdown in the
heart is accompanied by significant reduction in the pro-angiogenic
cleavage product N-acetyl-seryl-aspartyl-lysyl-proline (AcSDKP).
Although injection of AcSDKP was unable to rescue Tbeta4 mutant
hearts, it significantly enhanced endothelial cell differentiation
from adult epicardially derived precursor cells. This study identifies
Tbeta4 and AcSDKP as potent stimulators of coronary vasculogenesis
and angiogenesis, and reveals Tbeta4-induced adult epicardial cells
as a viable source of vascular progenitors for continued renewal
of regressed vessels at low basal level or sustained neovascularization
following cardiac injury.
Multipotent flk-1+ cardiovascular progenitor cells
give rise to the cardiomyocyte, endothelial, and vascular smooth
Kattman SJ, et al.
Dev Cell. 2006 Nov;11(5):723-32.
Abstract: Cell-tracing studies in the mouse indicate that the cardiac
lineage arises from a population that expresses the vascular endothelial
growth factor receptor 2 (VEGFR2, Flk-1), suggesting that it may
develop from a progenitor with vascular potential. Using the embryonic
stem (ES) cell differentiation model, we have identified a cardiovascular
progenitor based on the temporal expression of the primitive streak
(PS) marker brachyury and Flk-1. Comparable progenitors could also
be isolated from head-fold stage embryos. When cultured with cytokines
known to function during cardiogenesis, individual cardiovascular
progenitors generated colonies that displayed cardiomyocyte, endothelial,
and vascular smooth muscle (VSM) potential. Isolation and characterization
of this previously unidentified population suggests that the mammalian
cardiovascular system develops from multipotential progenitors.
Multipotent stromal cells from human marrow home to
and promote repair of pancreatic islets and renal glomeruli in diabetic
Lee RH, et al.
Proc Natl Acad Sci U S A. 2006 Nov 14;103(46):17438-43. Epub 2006
Abstract: We tested the hypothesis that multipotent stromal cells
from human bone marrow (hMSCs) can provide a potential therapy for
human diabetes mellitus. Severe but nonlethal hyperglycemia was
produced in NOD/scid mice with daily low doses of streptozotocin
on days 1-4, and hMSCs were delivered via intracardiac infusion
on days 10 and 17. The hMSCs lowered blood glucose levels in the
diabetic mice on day 32 relative to untreated controls (18.34 mM
+/- 1.12 SE vs. 27.78 mM +/- 2.45 SE, P = 0.0019). ELISAs demonstrated
that blood levels of mouse insulin were higher in the hMSC-treated
as compared with untreated diabetic mice, but human insulin was
not detected. PCR assays detected human Alu sequences in DNA in
pancreas and kidney on day 17 or 32 but not in other tissues, except
heart, into which the cells were infused. In the hMSC-treated diabetic
mice, there was an increase in pancreatic islets and beta cells
producing mouse insulin. Rare islets contained human cells that
colabeled for human insulin or PDX-1. Most of the beta cells in
the islets were mouse cells that expressed mouse insulin. In kidneys
of hMSC-treated diabetic mice, human cells were found in the glomeruli.
There was a decrease in mesangial thickening and a decrease in macrophage
infiltration. A few of the human cells appeared to differentiate
into glomerular endothelial cells. Therefore, the results raised
the possibility that hMSCs may be useful in enhancing insulin secretion
and perhaps improving the renal lesions that develop in patients
with diabetes mellitus.
Engraftment of Donor-Derived Epithelial Cells in Multiple
Organs Following Bone Marrow Transplantation into Newborn Mice
Emanuela M. Bruscia et al.
Stem Cells. 2006 Oct;24(10):2299-308. Epub 2006 Jun 22.
Abstract: Bone marrow-derived cells (BMDCs) can engraft as epithelial
cells throughout the body, including in the lung, liver, and gastrointestinal
(GI) tract following transplantation into lethally irradiated adult
recipients. Except for rare disease models in which marrow-derived
epithelial cells have a survival advantage over endogenous cells,
the currently attained levels of epithelial engraftment of BMDCs
are too low to be of therapeutic benefit. Here we tested whether
the degree of bone marrow to epithelial engraftment would be higher
if bone marrow transplantation (BMT) were performed on 1-day-old
mice, when tissues are undergoing rapid growth and remodeling. BMT
into newborn mice after multiple different regimens allowed for
robust hematopoietic engraftment, as well as the development of
rare donor-derived epithelial cells in the GI tract and lung but
not in the liver. The highest epithelial engraftment (0.02%) was
obtained in mice that received a preparative regimen of two doses
of busulfan in utero. When BMDCs were transplanted into myelosuppressed
newborn mice that lacked expression of the cystic fibrosis transmembrane
conductance regulator (CFTR) protein, the chloride channel that
is not functional in patients with cystic fibrosis, the engrafted
mice showed partial restoration of CFTR channel activity, suggesting
that marrow-derived epithelial cells in the GI tract were functional.
However, BMT into newborn mice, regardless of the myeloablative
regimen used, did not increase the number of bone marrow-derived
epithelial cells over that which occurs after BMT into lethally
irradiated adult mice.
Improved Liver Function in Patients with Liver Cirrhosis
After Autologous Bone Marrow Cell Infusion Therapy
Shuji Terai et al.
Stem Cells. 2006 Oct;24(10):2292-8. Epub 2006 Jun 15.
Abstract: Supplementation of mesenchymal stem cells (MSCs) during
hematopoietic stem cell (HSC) transplantation alleviates complications
such as graft-versus-host disease, leading to a speedy recovery
of hematopoiesis. To meet this clinical demand, a fast MSC expansion
method is required. In the present study, we examined the feasibility
of using a rotary bioreactor system to expand MSCs from isolated
bone marrow mononuclear cells. The cells were cultured in a rotary
bioreactor with Myelocult medium containing a combination of supplementary
factors, including stem cell factor and interleukin-3 and -6. After
8 days of culture, total cell numbers, Stro-1(+)CD44(+)CD34(-) MSCs,
and CD34(+)CD44(+)Stro-1(-) HSCs were increased 9-, 29-, and 8-fold,
respectively. Colony-forming efficiency-fibroblast per day of the
bioreactor-treated cells was 1.44-fold higher than that of the cells
without bioreactor treatment. The bioreactor-expanded MSCs showed
expression of primitive MSC markers endoglin (SH2) and vimentin,
whereas markers associated with lineage differentiation, including
osteocalcin (osteogenesis), type II collagen (chondrogenesis), and
C/EBP-alpha (CCAAT/enhancer-binding protein-alpha) (adipogenesis),
were not detected. Upon induction, the bioreactor-expanded MSCs
were able to differentiate into osteoblasts, chondrocytes, and adipocytes.
We conclude that the rotary bioreactor with the modified Myelocult
medium reported in this study may be used to rapidly expand MSCs.
Transforming growth factor alpha promotes sequential
conversion of mature astrocytes into neural progenitors and stem
Sharif A, et al.
Oncogene. 2006 Oct 23; [Epub ahead of print]
Abstract: An instability of the mature cell phenotype is thought
to participate to the formation of gliomas, primary brain tumors
deriving from astrocytes and/or neural stem cells. Transforming
growth factor alpha (TGFalpha) is an erbB1 ligand overexpressed
in the earliest stages of gliomas, and exerts trophic effects on
gliomal cells and astrocytes. Here, we questioned whether prolonged
TGFalpha exposure affects the stability of the normal mature astrocyte
phenotype. We first developed astrocyte cultures devoid of residual
neural stem cells or progenitors. We demonstrate that days of TGFalpha
treatment result in the functional conversion of a population of
mature astrocytes into radial glial cells, a population of neural
progenitors. TGFalpha-generated radial glial cells support embryonic
neurons migration, and give birth to cells of the neuronal lineage,
expressing neuronal markers and the electrophysiological properties
of neuroblasts. Lengthening TGFalpha treatment to months results
in the delayed appearance of cells with neural stem cells properties:
they form floating cellular spheres that are self-renewing, can
be clonally derived from a single cell and differentiated into cells
of the neuronal lineage. This study uncovers a novel population
of mature astrocytes capable, in response to a single epigenetic
factor, to regress progressively into a neural stem-like cell stage
via an intermediate progenitor stage.Oncogene advance online publication,
23 October 2006; doi:10.1038/sj.onc.1210071.
Risk-adapted craniospinal radiotherapy followed by
high-dose chemotherapy and stem-cell rescue in children with newly
diagnosed medulloblastoma (St Jude Medulloblastoma-96): long-term
results from a prospective, multicentre trial.
Gajjar A, et al.
Lancet Oncol. 2006 Oct;7(10):813-20.
BACKGROUND: Current treatment for medulloblastoma, which includes
postoperative radiotherapy and 1 year of chemotherapy, does not
cure many children with high-risk disease. We aimed to investigate
the effectiveness of risk-adapted radiotherapy followed by a shortened
period of dose-intense chemotherapy in children with medulloblastoma.
METHODS: After resection, patients were classified as having average-risk
medulloblastoma (< or = 1.5 cm2 residual tumour and no metastatic
disease) or high-risk medulloblastoma (> 1.5 cm2 residual disease
or metastatic disease localised to neuraxis) medulloblastoma. All
patients received risk-adapted craniospinal radiotherapy (23.4 Gy
for average-risk disease and 36.0-39.6 Gy for high-risk disease)
followed by four cycles of cyclophosphamide-based, dose-intensive
chemotherapy. Patients were assessed regularly for disease status
and treatment side-effects. The primary endpoint was 5-year event-free
survival; we also measured overall survival. This study is registered
with ClinicalTrials.gov, number NCT00003211.
FINDINGS: Of 134 children with medulloblastoma who underwent treatment
(86 average-risk, 48 high-risk), 119 (89%) completed the planned
protocol. No treatment-related deaths occurred. 5-year overall survival
was 85% (95% CI 75-94) in patients in the average-risk group and
70% (54-84) in those in the high-risk group (p=0.04); 5-year event-free
survival was 83% (73-93) and 70% (55-85), respectively (p=0.046).
For the 116 patients whose histology was reviewed centrally, histological
subtype correlated with 5-year event-free survival (p=0.04): 84%
(74-95) for classic histology, 77% (49-100) for desmoplastic tumours,
and 57% (33-80) for large-cell anaplastic tumours.
INTERPRETATION: Risk-adapted radiotherapy followed by a shortened
schedule of dose-intensive chemotherapy can be used to improve the
outcome of patients with high-risk medulloblastoma.
Embryonic-like stem cells from umbilical cord blood
and potential for neural modeling
McGuckin C et al.
Acta Neurobiol. Exp (2006) 66: 321-329.
Abstract: Stem cells offer the distinct prospect of changing the
face of human medicine. However, although they have potential to
form different tissues, are still in the early stages of development
as therapeutic interventions. The three most used stem cell sources
are umbilical cord blood, bone marrow and human embryos. Whilst,
cord blood is now used to treat over 70 disorders, at the time of
writing this manuscript, not a single disease has been overcome
or ameliorated using human embryonic stem cells. Advancing stem
cell medicine requires ethically sound and scientifically robust
models to develop tomorrow’s medicines. Media attention, however,
distracts from this reality; it is important to remember that stem
cells are a new visitor to the medical world and require more research.
Here we describe the utility of human cord blood to develop neural
models that are necessary to take stem cells to the next level –
into human therapies.
Aging does not alter the number or phenotype of putative
stem/progenitor cells in the neurogenic region of the hippocampus
Bharathi Hattiangady, Ashok K. Shetty
Neurobiol Aging (2006). doi:10.1016/j.neurobiolaging.2006.09.015.
Abstract: To investigate whether dramatically waned dentate neurogenesis
during aging is linked to diminution in neural stem/progenitor cell
(NSC) number, we counted cells immunopositive for Sox-2 (a putative
marker of NSCs) in the subgranular zone (SGZ) of young, middle-aged
and aged F344 rats. The young SGZ comprised ~50,000 Sox-2+ cells
and this amount did not diminish with aging. Quantity of GFAP+ cells
and vimentin+ radial glia also remained stable during aging in this
region. Besides, in all age groups, analogous fractions of Sox-2+
cells expressed GFAP (astrocytes/NSCs), NG-2 (oligodendrocyte-progenitors/NSCs),
vimentin (radial glia), S-100_ (astrocytes) and doublecortin (new
neurons). Nevertheless, analyses of Sox-2+ cells with proliferative
markers insinuated an increased quiescence of NSCs with aging. Moreover,
the volume of rat-endothelial-cell-antigen-1+ capillaries (vascular-niches)
within the SGZ exhibited an age-related decline, resulting in an
increased expanse between NSCs and capillaries. Thus, decreased
dentate neurogenesis during aging is not attributable to altered
number or phenotype of NSCs. Instead, it appears to be an outcome
of increased quiescence of NSCs due to changes in NSC milieu.
MCP-3 is a myocardial mesenchymal stem cell homing
Soren Schenk, et al.
Stem Cells, published online October 19, 2006; doi:10.1634/stemcells.2006-0293.
Abstract: Mesenchymal stem cells (MSC) have received attention for
their therapeutic potential in a number of disease states including
bone formation, diabetes, stem cell engraftment following marrow
transplantation, graft verse host disease, and heart failure. Despite
this diverse interest the molecular signals regulating MSC trafficking
to sites of injury are unclear. MSC are known to transiently home
to the freshly infracted myocardium. To identify MSC homing factors,
we determined chemokine expression pattern as a function of time
after MI. We merged these profiles with chemokine receptors expressed
on MSC but not cardiac fibroblasts, which do not home following
MI. This analysis identified MCP-3 as a potential MSC homing factor.
Over-expression of MCP-3 1 month after MI restored MSC homing to
the heart. Following serial infusions of MSC cardiac function improved
in MCP-3 expressing hearts (88.7%, p<0.001), but not in control
hearts (8.6%, p=0.47). MSC engraftment was not associated with differentiation
into cardiac myocytes. Rather MSC engraftment appeared to result
in recruitment of myofibroblasts and remodeling of the collagen
matrix. These data indicate that MCP-3 is an MSC homing factor;
local over-expression of MCP-3 recruits MSC to sites of injured
tissue and improves cardiac remodeling independent of cardiac myocyte
Cells isolated from umbilical cord tissue rescue photoreceptors
and visual functions in a rodent model of retinal disease
R. D. Lund et al.
Stem Cells, published online October 19, 2006; doi:10.1634/stemcells.2006-0308.
Abstract: Progressive photoreceptor degeneration resulting from
genetic and other factors is a leading and largely untreatable cause
of blindness worldwide. The object of this study was to find a cell
type that is effective in slowing the progress of such degeneration
in an animal model of human retinal disease, is safe and could be
generated in sufficient numbers for clinical application. We have
compared efficacy of four human derived cell types in preserving
photoreceptor integrity and visual functions after injection into
the subretinal space of the Royal College of Surgeons rat early
in the progress of degeneration. Umbilical tissue-derived cells,
placenta-derived cells, and mesenchymal stem cells were studied;
dermal fibroblasts served as cell controls. At various ages up to
100 days, electroretinogram responses, spatial acuity and luminance
threshold were measured. Both umbilical-derived and mesenchymal
cells significantly reduced the degree of functional deterioration
in each test. The effect of placental cells was little better than
controls. Umbilical tissue-derived cells gave large areas of photoreceptor
rescue; mesenchymal stem cells gave only localized rescue. Fibroblasts
gave sham levels of rescue. Donor cells were confined to the subretinal
space. There was no evidence of cell differentiation into neurons,
of tumor formation or other untoward pathology. Since the umbilical
tissue-derived cells demonstrated the best photoreceptor rescue
and unlike mesenchymal stem cells were capable of sustained population
doublings without karyotypic changes, it is proposed that they may
provide utility as a cell source for the treatment of retinal degenerative
diseases such as retinitis pigmentosa.
Sarcoma Derived from Cultured Mesenchymal Stem Cells
Jakub Tolar et al.
Stem Cells, published online October 12, 2006; doi:10.1634/stemcells.2005-0620.
Abstract: To study the biodistribution of Mesenchymal Stem Cells
(MSCs), we labeled adult murine C57BL/6 MSCs with firefly luciferase
and DsRed2 fluorescent protein using non-viral Sleeping Beauty transposons,
and co-infused labeled MSCs with bone marrow into irradiated allogeneic
recipients. Using in vivo whole body imaging, luciferase signals
were shown to be increased between weeks 3 and 12. Unexpectedly,
some mice with the highest luciferase signals died and all surviving
mice developed foci of sarcoma in lungs. Two mice also developed
sarcomas in their extremities. Common cytogenetic abnormalities
were identified in tumor cells isolated from different animals.
Original MSC cultures not labeled with transposons, as well as independently
isolated cultured MSCs were found to be cytogenetically abnormal.
Moreover, primary MSC.s derived from the bone marrow of both BALB/c
and C57BL/6 mice showed cytogenetic aberrations after several passages
in vitro, showing that transformation was not a strain specific
nor rare event. Clonal evolution was observed in vivo suggesting
that the critical transformation event(s) occurred before infusion.
Mapping of the transposition insertion sites did not identify an
obvious transposon related genetic abnormality and p53 was not overexpressed.
Infusion of MSC-derived sarcoma cells resulted in malignant lesions
in secondary recipients. This new sarcoma cell line, S1, is unique
in having a cytogenetic profile similar to human sarcoma and contains
bioluminescent and fluorescent genes making it useful for investigations
of cellular biodistribution and tumor response to therapy in vivo.
More importantly, our study indicates that sarcoma can evolve from
Transcoronary transplantation of progenitor cells
after myocardial infarction.
Assmus B, et al.
N Engl J Med. 2006 Sep 21;355(12):1222-32.
BACKGROUND: Pilot studies suggest that intracoronary transplantation
of progenitor cells derived from bone marrow (BMC) or circulating
blood (CPC) may improve left ventricular function after acute myocardial
infarction. The effects of cell transplantation in patients with
healed myocardial infarction are unknown.
METHODS: After an initial pilot trial involving 17 patients, we
randomly assigned, in a controlled crossover study, 75 patients
with stable ischemic heart disease who had had a myocardial infarction
at least 3 months previously to receive either no cell infusion
(23 patients) or infusion of CPC (24 patients) or BMC (28 patients)
into the patent coronary artery supplying the most dyskinetic left
ventricular area. The patients in the control group were subsequently
randomly assigned to receive CPC or BMC, and the patients who initially
received BMC or CPC crossed over to receive CPC or BMC, respectively,
at 3 months' follow-up.
RESULTS: The absolute change in left ventricular ejection fraction
was significantly greater among patients receiving BMC (+2.9 percentage
points) than among those receiving CPC (-0.4 percentage point, P=0.003)
or no infusion (-1.2 percentage points, P<0.001). The increase
in global cardiac function was related to significantly enhanced
regional contractility in the area targeted by intracoronary infusion
of BMC. The crossover phase of the study revealed that intracoronary
infusion of BMC was associated with a significant increase in global
and regional left ventricular function, regardless of whether patients
crossed over from control to BMC or from CPC to BMC.
CONCLUSIONS: Intracoronary infusion of progenitor cells is safe
and feasible in patients with healed myocardial infarction. Transplantation
of BMC is associated with moderate but significant improvement in
the left ventricular ejection fraction after 3 months. 2006 Massachusetts
Intracoronary bone marrow-derived progenitor cells
in acute myocardial infarction.
Schachinger V, et al.
N Engl J Med. 2006 Sep 21;355(12):1210-21.
BACKGROUND: Pilot trials suggest that the intracoronary administration
of autologous progenitor cells may improve left ventricular function
after acute myocardial infarction.
METHODS: In a multicenter trial, we randomly assigned 204 patients
with acute myocardial infarction to receive an intracoronary infusion
of progenitor cells derived from bone marrow (BMC) or placebo medium
into the infarct artery 3 to 7 days after successful reperfusion
RESULTS: At 4 months, the absolute improvement in the global left
ventricular ejection fraction (LVEF) was significantly greater in
the BMC group than in the placebo group (mean [+/-SD] increase,
5.5+/-7.3% vs. 3.0+/-6.5%; P=0.01). Patients with a baseline LVEF
at or below the median value of 48.9% derived the most benefit (absolute
improvement in LVEF, 5.0%; 95% confidence interval, 2.0 to 8.1).
At 1 year, intracoronary infusion of BMC was associated with a reduction
in the prespecified combined clinical end point of death, recurrence
of myocardial infarction, and any revascularization procedure (P=0.01).
CONCLUSIONS: Intracoronary administration of BMC is associated with
improved recovery of left ventricular contractile function in patients
with acute myocardial infarction. Large-scale studies are warranted
to examine the potential effects of progenitor-cell administration
on morbidity and mortality. 2006 Massachusetts Medical Society
Intracoronary injection of mononuclear bone marrow
cells in acute myocardial infarction.
Lunde K, et al.
N Engl J Med. 2006 Sep 21;355(12):1199-209.
BACKGROUND: Previous studies have shown improvement in left ventricular
function after intracoronary injection of autologous cells derived
from bone marrow (BMC) in the acute phase of myocardial infarction.
We designed a randomized, controlled trial to further investigate
the effects of this treatment.
METHODS: Patients with acute ST-elevation myocardial infarction
of the anterior wall treated with percutaneous coronary intervention
were randomly assigned to the group that underwent intracoronary
injection of autologous mononuclear BMC or to the control group,
in which neither aspiration nor sham injection was performed. Left
ventricular function was assessed with the use of electrocardiogram-gated
single-photon-emission computed tomography (SPECT) and echocardiography
at baseline and magnetic resonance imaging (MRI) 2 to 3 weeks after
the infarction. These procedures were repeated 6 months after the
infarction. End points were changes in the left ventricular ejection
fraction (LVEF), end-diastolic volume, and infarct size.
RESULTS: Of the 50 patients assigned to treatment with mononuclear
BMC, 47 underwent intracoronary injection of the cells at a median
of 6 days after myocardial infarction. There were 50 patients in
the control group. The mean (+/-SD) change in LVEF, measured with
the use of SPECT, between baseline and 6 months after infarction
for all patients was 7.6+/-10.4 percentage points. The effect of
BMC treatment on the change in LVEF was an increase of 0.6 percentage
point (95% confidence interval [CI], -3.4 to 4.6; P=0.77) on SPECT,
an increase of 0.6 percentage point (95% CI, -2.6 to 3.8; P=0.70)
on echocardiography, and a decrease of 3.0 percentage points (95%
CI, 0.1 to -6.1; P=0.054) on MRI. The two groups did not differ
significantly in changes in left ventricular end-diastolic volume
or infarct size and had similar rates of adverse events.
CONCLUSIONS: With the methods used, we found no effects of intracoronary
injection of autologous mononuclear BMC on global left ventricular
function. 2006 Massachusetts Medical Society
Integrins Are Markers of Human Neural Stem Cells
Peter E. Hall et al.
Stem Cells. 2006 Sep;24(9):2078-84. Epub 2006 May 11.
Abstract: The identification of markers for the isolation of human
neural stem cells (hNSCs) is essential for studies of their biology
and therapeutic applications. This study investigated expression
of the integrin receptor family by hNSCs as potential markers. Selection
of alpha6(hi) or beta1(hi) cells by fluorescence-activated cell
sorting led to an enrichment of human neural precursors, as shown
by both neurosphere forming assays and increased expression of prominin-1,
sox2, sox3, nestin, bmi1, and musashi1 in the beta1(hi) population.
Cells expressing high levels of beta1 integrin also expressed prominin-1
(CD133), a marker previously used to isolate hNSCs, and selection
using integrin beta1(hi) cells or prominin-1(hi) cells was found
to be equally effective at enriching for hNSCs from neurospheres.
Therefore, integrin subunits alpha6 and beta1 are highly expressed
by human neural precursors and represent convenient markers for
their prospective isolation.
High Yield of Cells Committed to the Photoreceptor
Fate from Expanded Mouse Retinal Stem Cells
Faten Merhi-Soussi et al.
Stem Cells. 2006 Sep;24(9):2060-70. Epub 2006 Apr 27.
Abstract: The purpose of the present work was to generate, from
retinal stem cells (RSCs), a large number of cells committed toward
the photoreceptor fate in order to provide an unlimited cell source
for neurogenesis and transplantation studies. We expanded RSCs (at
least 34 passages) sharing characteristics of radial glial cells
and primed the cells in vitro with fibroblast growth factor (FGF)-2
for 5 days, after which cells were treated with the B27 supplement
to induce cell differentiation and maturation. Upon differentiation,
cells expressed cell type-specific markers corresponding to neurons
and glia. We show by immunocytochemistry analysis that a subpopulation
of differentiated cells was committed to the photoreceptor lineage
given that these cells expressed the photoreceptor proteins recoverin,
peripherin, and rhodopsin in a same ratio. Furthermore, cells infected
during the differentiation procedure with a lentiviral vector expressing
green fluorescent protein (GFP) under the control of either the
rhodopsin promoter or the interphotoreceptor retinoidbinding protein
(IRBP) promoter, expressed GFP. FGF-2 priming increased neuronal
differentiation while decreasing glia generation. Reverse transcription-polymerase
chain reaction analyses revealed that the differentiated cells expressed
photoreceptor-specific genes such as Crx, rhodopsin, peripherin,
IRBP, and phosphodiesterase-_. Quantification of the differentiated
cells showed a robust differentiation into the photoreceptor lineage:
Approximately 25%–35% of the total cells harbored photoreceptor
markers. The generation of a significant number of nondifferentiated
RSCs as well as differentiated photoreceptors will enable researchers
to determine via transplantation studies which cells are the most
adequate to integrate a degenerating retina.
Bioreactor Expansion of Human Adult Bone Marrow-Derived
Mesenchymal Stem Cells
Xi Chen et al.
Stem Cells. 2006 Sep;24(9):2052-9. Epub 2006 May 25.
Abstract: Supplementation of mesenchymal stem cells (MSCs) during
hematopoietic stem cell (HSC) transplantation alleviates complications
such as graft-versus-host disease, leading to a speedy recovery
of hematopoiesis. To meet this clinical demand, a fast MSC expansion
method is required. In the present study, we examined the feasibility
of using a rotary bioreactor system to expand MSCs from isolated
bone marrow mononuclear cells. The cells were cultured in a rotary
bioreactor with Myelocult medium containing a combination of supplementary
factors, including stem cell factor and interleukin-3 and -6. After
8 days of culture, total cell numbers, Stro-1(+)CD44(+)CD34(-) MSCs,
and CD34(+)CD44(+)Stro-1(-) HSCs were increased 9-, 29-, and 8-fold,
respectively. Colony-forming efficiency-fibroblast per day of the
bioreactor-treated cells was 1.44-fold higher than that of the cells
without bioreactor treatment. The bioreactor-expanded MSCs showed
expression of primitive MSC markers endoglin (SH2) and vimentin,
whereas markers associated with lineage differentiation, including
osteocalcin (osteogenesis), type II collagen (chondrogenesis), and
C/EBP-alpha (CCAAT/enhancer-binding protein-alpha) (adipogenesis),
were not detected. Upon induction, the bioreactor-expanded MSCs
were able to differentiate into osteoblasts, chondrocytes, and adipocytes.
We conclude that the rotary bioreactor with the modified Myelocult
medium reported in this study may be used to rapidly expand MSCs.
Multi-potent mesenchymal stromal cells in blood
Qiling He et al.
Stem Cells. published online Sep 14, 2006; DOI: 10.1634/stemcells.2006-0335.
Abstract: Peripheral blood-derived multi-potent mesenchymal stromal
cells circulate in low number. They share, though not all, but most
of the surface markers with bone marrow-derived multi-potent mesenchymal
stromal cells, possess diverse and complicated gene expression characteristics,
and are capable of differentiating along and even beyond mesenchymal
lineages. Although their origin and physio-pathological function
are still unclear, their presence in the adult peripheral blood
might relate to some interesting but controversial subjects in the
filed of adult stem cell biology, such as systemic migration of
bone marrowderived multi-potent mesenchymal stromal cells and the
existence of common hematopoietic-mesenchymal precursors. In this
review, current studies /knowledge about peripheral blood-derived
multi-potent mesenchymal stromal cells is summarized and the above-mentioned
topics are discussed.
Effective cell and gene therapy in a murine model
of Gaucher disease.
Enquist IB, et al.
Proc Natl Acad Sci U S A. 2006 Sep 12;103(37):13819-24. Epub 2006
Abstract: Gaucher disease (GD) is a lysosomal storage disorder due
to an inherited deficiency in the enzyme glucosylceramidase (GCase)
that causes hepatosplenomegaly, cytopenias, and bone disease as
key clinical symptoms. Previous mouse models with GCase deficiency
have been lethal in the perinatal period or viable without displaying
the clinical features of GD. We have generated viable mice with
characteristic clinical symptoms of type 1 GD by conditionally deleting
GCase exons 9-11 upon postnatal induction. Both transplantation
of WT bone marrow (BM) and gene therapy through retroviral transduction
of BM from GD mice prevented development of disease and corrected
an already established GD phenotype. The gene therapy approach generated
considerably higher GCase activity than transplantation of WT BM.
Strikingly, both therapeutic modalities normalized glucosylceramide
levels and practically no infiltration of Gaucher cells could be
observed in BM, spleen, and liver, demonstrating correction at 5-6
months after treatment. The findings demonstrate the feasibility
of gene therapy for type 1 GD in vivo. Our type 1 GD mice will serve
as an excellent tool in the continued efforts toward development
of safe and efficient cell and gene therapy for type 1 GD.
Isolation and characterization of multipotent progenitor
cells from the Bowman's capsule of adult human kidneys.
Sagrinati C, et al.
J Am Soc Nephrol. 2006 Sep;17(9):2443-56. Epub 2006 Aug 2.
Abstract: Regenerative medicine represents a critical clinical goal
for patients with ESRD, but the identification of renal adult multipotent
progenitor cells has remained elusive. It is demonstrated that in
human adult kidneys, a subset of parietal epithelial cells (PEC)
in the Bowman's capsule exhibit coexpression of the stem cell markers
CD24 and CD133 and of the stem cell-specific transcription factors
Oct-4 and BmI-1, in the absence of lineage-specific markers. This
CD24+CD133+ PEC population, which could be purified from cultured
capsulated glomeruli, revealed self-renewal potential and a high
cloning efficiency. Under appropriate culture conditions, individual
clones of CD24+CD133+ PEC could be induced to generate mature, functional,
tubular cells with phenotypic features of proximal and/or distal
tubules, osteogenic cells, adipocytes, and cells that exhibited
phenotypic and functional features of neuronal cells. The injection
of CD24+CD133+ PEC but not of CD24-CD133- renal cells into SCID
mice that had acute renal failure resulted in the regeneration of
tubular structures of different portions of the nephron. More important,
treatment of acute renal failure with CD24+CD133+ PEC significantly
ameliorated the morphologic and functional kidney damage. This study
demonstrates the existence and provides the characterization of
a population of resident multipotent progenitor cells in adult human
glomeruli, potentially opening new avenues for the development of
regenerative medicine in patients who have renal diseases.
Human neural stem cells target experimental intracranial
medulloblastoma and deliver a therapeutic gene leading to tumor
Kim SK, et al.
Clin Cancer Res. 2006 Sep 15;12(18):5550-6.
PURPOSE: Medulloblastoma, a malignant pediatric brain tumor, is
incurable in about one third of patients despite multimodal treatments.
In addition, current therapies can lead to long-term disabilities.
Based on studies of the extensive tropism of neural stem cells (NSC)
toward malignant gliomas and the secretion of growth factors common
to glioma and medulloblastoma, we hypothesized that NSCs could target
medulloblastoma and be used as a cellular therapeutic delivery system.
Experimental Design: The migratory ability of HB1.F3 cells (an immortalized,
clonal human NSC line) to medulloblastoma was studied both in vitro
and in vivo. As proof-of-concept, we used HB1.F3 cells engineered
to secrete the prodrug activating enzyme cytosine deaminase. We
investigated the potential of human NSCs to deliver a therapeutic
gene and reduce tumor growth.
RESULTS: The migratory capacity of HB1.F3 cells was confirmed by
an in vitro migration assay, and corroborated in vivo by injecting
chloromethylbenzamido-Dil-labeled HB1.F3 cells into the hemisphere
contralateral to established medulloblastoma in nude mice. In vitro
studies showed the therapeutic efficacy of HB1.F3-CD on Daoy cells
in coculture experiments. In vitro therapeutic studies were conducted
in which animals bearing intracranial medulloblastoma were injected
ipsilaterally with HB1.F3-CD cells followed by systemic 5-flourocytosine
treatment. Histologic analyses showed that human NSCs migrate to
the tumor bed and its boundary, resulting in a 76% reduction of
tumor volume in the treatment group (P<0.01).
CONCLUSION: These studies show for the first time the potential
of human NSCs as an effective delivery system to target and disseminate
therapeutic agents to medulloblastoma.
A phase 2 study of high-activity( 186)Re-HEDP with
autologous peripheral blood stem cell transplant in progressive
hormone-refractory prostate cancer metastatic to bone.
O'Sullivan JM, et al.
Eur J Nucl Med Mol Imaging. 2006 Sep;33(9):1055-1061. Epub 2006
PURPOSE: We investigated the potential for improvement in disease
control by use of autologous peripheral blood stem cell transplant
(PBSCT) to permit administration of high activities of (186)Re-hydroxyethylidene
diphosphonate (HEDP) in patients with progressive hormone-refractory
prostate cancer (HRPC).
METHODS: Eligible patients had progressive HRPC metastatic to bone,
good performance status and minimal soft tissue disease. Patients
received 5,000 MBq of (186)Re-HEDP i.v., followed 14 days later
by PBSCT. Response was assessed using PSA, survival, pain scores
and quality of life.
RESULTS: Thirty-eight patients with a median age of 67 years (range
50-77) and a median PSA of 57 ng/ml (range 4-3,628) received a median
activity of 4,978 MBq (186)Re-HEDP (range 4,770-5,100 MBq). The
most serious toxicity was short-lived grade 3 thrombocytopenia in
8 (21%) patients. The median survival of the group is 21 months
(95%CI 18-24 months) with Kaplan-Meier estimated 1- and 2-year survival
rates of 83% and 40% respectively. Thirty-one patients (81%, 95%
CI 66-90%) had stable or reduced PSA levels 3 months post therapy
while 11 (29%, 95% CI 15-49%) had PSA reductions of >50% lasting
>4 weeks. Quality of life measures were stable or improved in
27 (66%) at 3 months.
CONCLUSION: We have shown that it is feasible and safe to deliver
high-activity radioisotope therapy with PBSCT to men with metastatic
HRPC. Response rates and survival data are encouraging; however,
further research is needed to define optimal role of this treatment
Adipose-derived stem and progenitor cells as fillers
in plastic and reconstructive surgery.
Moseley TA, et al.
Plast Reconstr Surg. 2006 Sep;118(3 Suppl):121S-128S.
Abstract: Plastic surgeons are keenly aware of the principle "replace
like with like." This principle underlies much of the rationale
behind the clinical use of autologous fat transplantation, despite
the procedure's drawbacks. Autologous fat transplantation is frequently
used for a variety of cosmetic and reconstructive indications not
limited to posttraumatic defects of the face and body, involutional
disorders such as hemifacial atrophy, sequelae of radiation therapy,
and many aesthetic uses such as lip and facial augmentation and
wrinkle therapy. However, the limitations of fat transplantation
are well known, particularly the long-term unpredictability of volume
maintenance. Regenerative cell-based strategies such as those encompassing
the use of stem cells hold tremendous promise for augmentation of
the soft-tissue space. Preclinical studies and early clinical series
show that adipose-derived stem cells offer the possibility of finally
fulfilling the key principle of replacing like with like as an aesthetic
filler, without the drawbacks of current technology.
Ex Vivo Expansion Does Not Alter the Capacity of Umbilical
Cord Blood CD34_ Cells to Generate Functional T Lymphocytes and
LADAN KOBARI et al.
Stem Cells. 2006;24:2150–2157.
Abstract: We examined whether ex vivo expansion of umbilical cord
blood progenitor cells affected their capacity to generate immune
cells such as T lymphocytes (TLs) and dendritic cells (DCs). The
capacity to generate TLs from cord blood CD34_ cells expanded for
14 days (d14) was compared with that of nonexpanded CD34_ cells
(d0) using fetal thymus organ cultures or transfer into nonobese
diabetic/severe combined immunodeficient mice. The cell preparations
yielded comparable percentages of immature (CD4_CD8_, CD4_CD8_)
TLs and functional mature (CD3_CD4_, CD3_CD8_) TLs with an analogous
TCR (T-cell receptor)-V_ repertoire pattern. As regards DCs, d0
and d14 CD34_ cells also yielded similar percentages of CD1a_ DCs
with the same expression levels of HLA-DR, costimulatory and adhesion
molecules, and chemokine receptors. DCs derived from either d14
or d0 CD34_ stimulated allogeneic TLs to the same extent, and the
cytokine pattern production of these allogeneic TLs was similar
with no shift toward a predominant Th1 or Th2 response. Even though
the intrinsic capacity of d14 CD34_ cells to generate DCs was 13-fold
lower than that of d0 CD34_ cells, this reduction was offset by
the prior amplification of the CD34_ cells, resulting in the overall
production of 15-fold more DCs. These data indicate that ex vivo
expansion of CD34_ cells does not impair T lymphopoiesis nor DC
In Vivo Bone Formation by Human Bone Marrow Stromal
Cells: Reconstruction of the Mouse Calvarium and Mandible
MAHESH H. MANKANI et al.
Stem Cells. 2006 Sep;24(9):2140-9. Epub 2006 Jun 8.
Abstract: Bone marrow stromal cells (BMSCs) contain a subset of
multipotent cells with the potential to repair hard-tissue defects.
Mouse BMSCs, combined with a collagen carrier, can close critical-sized
homologous mouse calvarial defects, but this new bone has a poor
union with the adjacent calvarium. When human BMSCs are transplanted
for the purpose of engineering new bone, best results can be achieved
if the cells are combined with hydroxyapatite/tricalcium phosphate
(HA/TCP) particles. Here, we demonstrate that transplantation of
cultured human BMSCs in conjunction with HA/TCP particles can be
used successfully to close mouse craniofacial bone defects and that
removal of the periosteum from the calvarium significantly enhances
union with the transplant. Transplants were followed for up to 96
weeks and were found to change in morphology but not bone content
after 8 weeks; this constitutes the first description of human BMSCs
placed long-term to heal bone defects. New bone formation continued
to occur in the oldest transplants, confirmed by tetracycline labeling.
Additionally, the elastic modulus of this engineered bone resembled
that of the normal mouse calvarium, and our use of atomic force
microscopy (AFM)-based nanoindentation offered us the first opportunity
to compare these small transplants against equally minute mouse
bones. Our results provide insights into the long-term behavior
of newly engineered orthotopic bone from human cells and have powerful
implications for therapeutic human BMSC transplantation.
Growth factor-stimulated generation of new cortical
tissue and functional recovery after stroke damage to the motor
cortex of rats.
Kolb B, et al.
J Cereb Blood Flow Metab. 2006 Sep 20; [Epub ahead of print]
Abstract: Recent studies suggest that proliferation in the adult
forebrain subventricular zone increases in response to a forebrain
stroke and intraventricular infusions of growth factors enhance
this response. The potential for growth factor infusions to regenerate
the damaged motor cortex and promote recovery of motor function
after stroke has not been examined. Here, we report that intraventricular
infusions of epidermal growth factor and erythropoietin together,
but not individually, promote substantial regeneration of the damaged
cerebral cortex and reverse impairments in spontaneous and skilled
motor tasks, in a rat model of stroke. Cortical regeneration and
functional recovery occurred even when growth factor administration
was delayed for up to 7 days after the stroke-induced lesion. Cell
tracking demonstrated the contribution of neural precursors originating
in the forebrain subventricular zone to the regenerated cortex.
Strikingly, removal of the regenerated cortical tissue reversed
the growth factor-induced functional recovery. These findings reveal
that specific combinations of growth factors can mobilize endogenous
adult neural stem cells to promote cortical tissue re-growth and
functional recovery after stroke.Journal of Cerebral Blood Flow
& Metabolism advance online publiaction, 20 September 2006;
Synergy between immune cells and adult neural stem/progenitor
cells promotes functional recovery from spinal cord injury.
Ziv Y, et al.
Proc Natl Acad Sci U S A. 2006 Aug 29;103(35):13174-9. Epub 2006
Abstract: The well regulated activities of microglia and T cells
specific to central nervous system (CNS) antigens can contribute
to the protection of CNS neural cells and their renewal from adult
neural stem/progenitor cells (aNPCs). Here we report that T cell-based
vaccination of mice with a myelin-derived peptide, when combined
with transplantation of aNPCs into the cerebrospinal fluid (CSF),
synergistically promoted functional recovery after spinal cord injury.
The synergistic effect was correlated with modulation of the nature
and intensity of the local T cell and microglial response, expression
of brain-derived neurotrophic factor and noggin protein, and appearance
of newly formed neurons from endogenous precursor-cell pools. These
results substantiate the contention that the local immune response
plays a crucial role in recruitment of aNPCs to the lesion site,
and suggest that similar immunological manipulations might also
serve as a therapeutic means for controlled migration of stem/progenitor
cells to other acutely injured CNS sites.
Derivation and large-scale expansion of multipotent
astroglial neural progenitors from adult human brain.
Walton NM, et al.
Development. 2006 Sep;133(18):3671-81. Epub 2006 Aug 16.
Abstract: The isolation and expansion of human neural cell types
has become increasingly relevant in restorative neurobiology. Although
embryonic and fetal tissue are frequently envisaged as providing
sufficiently primordial cells for such applications, the developmental
plasticity of endogenous adult neural cells remains largely unclear.
To examine the developmental potential of adult human brain cells,
we applied conditions favoring the growth of neural stem cells to
multiple cortical regions, resulting in the identification and selection
of a population of adult human neural progenitors (AHNPs). These
nestin(+) progenitors may be derived from multiple forebrain regions,
are maintainable in adherent conditions, co-express multiple glial
and immature markers, and are highly expandable, allowing a single
progenitor to theoretically form sufficient cells for approximately
4x10(7) adult brains. AHNPs longitudinally maintain the ability
to generate both glial and neuronal cell types in vivo and in vitro,
and are amenable to genetic modification and transplantation. These
findings suggest an unprecedented degree of inducible plasticity
is retained by cells of the adult central nervous system.
Isolation of mesenchymal stem cells from human vermiform
De Coppi P, et al.
J Surg Res. 2006 Sep;135(1):85-91. Epub 2006 May 2.
Abstract: BACKGROUND: Recent findings have shown that pluripotent
stem cells exist in areas outside the bone marrow (BM). Moreover,
it has been demonstrated that the appendix is important for the
development of mucosal gut immunity, and hematopoietic progenitors
have been isolated from animal and human appendices.
MATERIALS AND METHODS: Non-inflamed appendices removed during laparotomy were
processed and cultured until the appearance of adherent cells. Differentiations
(performed under osteogenic, adipogenic, and myogenic conditions)
were confirmed by immunohistochemistry and cytochemistry. Polymerase
chain reaction and cytofluorimetric analyses were performed to evidence
the presence of genes and protein specific lineages in appendix-derived
mesenchymal stem cells (ADMCs). RESULTS: ADMCs were present in non-inflamed
appendices. ADMCs under osteogenic conditions differentiated in
osteoblasts and showed increased alkaline phosphatase expression;
at the gene level, we observed the expression of Core binding factor
alpha 1 (Cbfa1) and osteocalcin in osteogenic induced ADMCs. Under
adipogenic conditions, lipidic drops in the cytoplasm, expression
of lipoprotein lipase (LpL), and peroxisome proliferator-activated
receptor gamma were observed; under myogenic conditions, myotubes
expressing muscle specific proteins like desmin were formed. Myogenic
regulatory factor 4 and MyoD were selectively induced in the ADMCs
under myogenic conditions.
CONCLUSIONS: This study shows for the
first time that mesenchymal stem cells can be isolated from normal
appendices obtained from a pediatric and adult age group (0-18 years
of age). This finding not only may further knowledge of the maturation
of the intestinal immunesystem but also could indicate a new physiological
role of the human vermiform appendix.
Differentiation of adult stem cells derived from bone
marrow stroma into Leydig or adrenocortical cells.
Yazawa T, et al.
Endocrinology. 2006 Sep;147(9):4104-11. Epub 2006 May 25.
Abstract: Adult stem cells from bone marrow, referred to as mesenchymal
stem cells or marrow stromal cells (MSCs), are defined as pluripotent
cells and have the ability to differentiate into multiple mesodermal
cells. In this study, we investigated whether MSCs from rat, mouse,
and human are able to differentiate into steroidogenic cells. When
transplanted into immature rat testes, adherent marrow-derived cells
(including MSCs) were found to be engrafted and differentiate into
steroidogenic cells that were indistinguishable from Leydig cells.
Isolated murine MSCs transfected with green fluorescence protein
driven by the promoter of P450 side-chain cleaving enzyme gene (CYP11A),
a steroidogenic cell-specific gene, were used to detect steroidogenic
cell production in vitro. During in vitro differentiation, green
fluorescence protein-positive cells, which had characteristics similar
to those of Leydig cells, were found. Stable transfection of murine
MSCs with a transcription factor, steroidogenic factor-1, followed
by treatment with cAMP almost recapitulated the properties of Leydig
cells, including the production of testosterone. Transfection of
human MSCs with steroidogenic factor-1 also led to their conversion
to steroidogenic cells, but they appeared to be glucocorticoid-
rather than testosterone-producing cells. These results indicate
that MSCs represent a useful source of stem cells for producing
steroidogenic cells that may provide basis for their use in cell
and gene therapy.
Autologous adipose tissue-derived stromal cells for
treatment of spinal cord injury.
Kang SK, et al.
Stem Cells Dev. 2006 Aug;15(4):583-94.
Abstract: Isolated rat adipose tissue-derived stromal cells (rATSCs)
contain pluripotent cells that can be differentiated into a variety
of cell lineages, including neural cells. Recent work has shown
that ATSCs can make neurosphere-like clumps and differentiate into
neuron-like cells expressing neuronal markers, but their therapeutic
effect is unclear. Here we report that intravenous infusion of oligodendrocyte
precursor cells (OPCs) derived from rATSC autograft cells sources
improve motor function in rat models of spinal cord injury (SCI).
After 4-5 weeks, transplanted rATSC-OPC cells survived and migrated
into the injured region of SCI very efficiently (30-35%) and migrated
cells were partially differentiated into neurons and oligodendrocyte.
Also, we found some of the engrafted OPCs migrated and integrated
in the kidney, brain, lung, and liver through the intravenous system.
Behavioral analysis revealed the locomotor functions of OPC-autografted
SCI rats were significantly restored. Efficient migration of intravenously
engrafted rATSC-OPCs cells into SCI lesion suggests that SCI-induced
chemotaxic factors facilitate migration of rATSC-OPCs. Here, we
verified that engrafted rATSCs and SCI-induced chemotaxic factors
indeed play an important role in proliferation, migration, and differentiation
of endogeneous spinal cord-derived neural progenitor cells in the
injured region. In transplantation paradigms, the interaction between
engrafted rATSC-OPCs and endogeneous spinal cord-derived neuronal
progenitor cells will be important in promoting healing through
fate decisions, resulting in coordinated induction of cell migration
Cord blood mesenchymal stem cells: Potential use in
El-Badri NS, et al.
Stem Cells Dev. 2006 Aug;15(4):497-506.
Abstract: Our previous studies demonstrate enhanced neural protective
effects of cord blood (CB) cells in comparison to stem cells from
adult marrow. To determine further whether mesenchymal stem cells
(MSCs) derived from human umbilical cord blood (hUCB) possess optimal
characteristics for neural therapy, we isolated populations of plastic-adherent
CB MSCs. These cells generated CD34-, CD45-, CD11b-, CD3-, CD19-
cells in culture and failed to produce CFU-M, CFU-GEMM, or CFU-GM
hematopoietic colonies in methylcellulose. However, cultured CB
MSCs possessed a remarkable ability to support proliferation as
well as differentiation of hematopoietic cells in vitro. In addition,
supernatants from cultured CB MSCs promoted survival of NT2 N neural
cells and peripheral blood mononuclear cells (MNCs) cultured under
conditions designed to induce cell stress and limit protein synthesis.
After incubation in neural differentiation medium, CB MSCs expressed
the neural cell-surface antigen A2B5, the neurofilament polypeptide
NF200, the oligodendrocyte precursor marker 04, intermediate filament
proteins characteristic of neural differentiation (nestin and vimentin),
as well as the astrocyte marker glial fibrillary acidic protein
(GFAP) and the neural progenitor marker TUJ-1. We examined the immunomodulatory
effects of the CB MSCs after co-culture with murine splenocytes.
Whereas spleen cells from normal C57Bl/6 mice exhibited a prominent
immunoglobulin M (IgM) response after immunization with the T cell-dependent
antigen sheep red blood cells, this response was significantly decreased
after incubation with CB MSCs. These data indicate that CB MSCs
possess multiple utilities that may contribute to their therapeutic
potency in the treatment of neurological disorders.
Threshold of lung injury required for the appearance
of marrow-derived lung epithelia.
Herzog EL, et al.
Stem Cells. 2006 Aug;24(8):1986-92.
Abstract: Bone marrow-derived cells (BMDCs) can adopt an epithelial
phenotype in the lung following bone marrow transplantation (BMT).
This phenomenon has been assumed to result from the lung injury
that occurs with myeloablative radiation. To date, no study has
related the degree of epithelial chimerism following bone marrow
transplantation to the lung damage induced by preconditioning for
BMT. Such a goal is crucial to understanding the local host factors
that promote the engraftment of BMDCs as lung epithelia. We undertook
this aim by performing sex-mismatched bone marrow transplantation
using a variety of preconditioning regimens and comparing measurements
of lung injury (bronchoalveolar lavage [BAL] cell count, alveolar-capillary
leak assayed by BAL protein levels, and terminal deoxynucleotidyl
transferase dUTP nick-end labeling analysis on epithelial cells)
with rigorous methods to quantify bone marrow-derived lung epithelia
(costaining for epithelial and donor markers on tissue sections
and isolated lung epithelia in recipient mice). We found that only
at doses that induced lung injury could marrow derived lung epithelium
be identified following BMT. With irradiation doses less than 1,000
centigray (cGy), there was little to no apparent injury to the lung,
and there were no marrow-derived pneumocytes despite high levels
of hematopoietic chimerism. In contrast, 4 days after either split
or single-dose 1,000 cGy irradiation, nearly 15% of lung epithelia
were apoptotic, and with this dose, marrow-derived type II pneumocytes
(0.2%) were present at 28 days. These data indicate a critical relationship
between lung injury and the phenotypic change from BMDCs to lung
The phenotypes of pluripotent human hepatic progenitors.
Schmelzer E, et al.
Stem Cells. 2006 Aug;24(8):1852-8. Epub 2006 Apr 20.
Abstract: Human livers contain two pluripotent hepatic progenitors,
hepatic stem cells and hepatoblasts, with size, morphology, and
gene expression profiles distinct from that of mature hepatocytes.
Hepatic stem cells, the precursors to hepatoblasts, persist in stable
numbers throughout life, and those isolated from the livers of all
age donors from fetal to adult are essentially identical in their
gene and protein expression profiles. The gene expression profile
of hepatic stem cells throughout life consists of high levels of
expression of cytokeratin 19 (CK19), neuronal cell adhesion molecule
(NCAM), epithelial cell adhesion molecule (EpCAM), and claudin-3
(CLDN-3); low levels of albumin; and a complete absence of expression
of alpha-fetoprotein (AFP) and adult liver-specific proteins. By
contrast, hepatoblasts, the dominant cell population in fetal and
neonatal livers, decline in numbers with age and are found as <0.1%
of normal adult livers. They express high levels of AFP, elevated
levels of albumin, low levels of expression of adult liver-specific
proteins, low levels of CK19, and a loss of NCAM and CLDN-3. Mature
hepatocytes lack expression altogether of EpCAM, NCAM, AFP, CLDN-3,
cytokeratin 19, and have acquired the well-known adult-specific
profile that includes expression of high levels of albumin, cytochrome
P4503A4, connexins, phosphoenolpyruvate carboxykinase, and transferrin.
Thus, hepatic stem cells have a unique stem cell phenotype, whereas
hepatoblasts have low levels of expression of both stem cell genes
and genes expressed in high levels in mature hepatocytes.
Clonogenic multipotent stem cells in human adipose
tissue differentiate into functional smooth muscle cells.
Rodriguez LV, et al.
Proc Natl Acad Sci U S A. 2006 Aug 8;103(32):12167-72. Epub 2006
Abstract: Smooth muscle is a major component of human tissues and
is essential for the normal function of a multitude of organs including
the intestine, urinary tract and the vascular system. The use of
stem cells for cell-based tissue engineering and regeneration strategies
represents a promising alternative for smooth muscle repair. For
such strategies to succeed, a reliable source of smooth muscle precursor
cells must be identified. Adipose tissue provides an abundant source
of multipotent cells. In this study, the capacity of processed lipoaspirate
(PLA) and adipose-derived stem cells to differentiate into phenotypic
and functional smooth muscle cells was evaluated. To induce differentiation,
PLA cells were cultured in smooth muscle differentiation medium.
Smooth muscle differentiation of PLA cells induced genetic expression
of all smooth muscle markers and further confirmed by increased
protein expression of smooth muscle cell-specific alpha actin (ASMA),
calponin, caldesmon, SM22, myosin heavy chain (MHC), and smoothelin.
Clonal studies of adipose derived multipotent cells demonstrated
differentiation of these cells into smooth muscle cells in addition
to trilineage differentiation capacity. Importantly, smooth muscle-differentiated
cells, but not their precursors, exhibit the functional ability
to contract and relax in direct response to pharmacologic agents.
In conclusion, adipose-derived cells have the potential to differentiate
into functional smooth muscle cells and, thus, adipose tissue can
be a useful source of cells for treatment of injured tissues where
smooth muscle plays an important role.
Differentiation of umbilical cord blood-derived multilineage
progenitor cells into respiratory epithelial cells.
Berger MJ, et al.
BACKGROUND: Umbilical cord blood (UCB) has been examined for the
presence of stem cells capable of differentiating into cell types
of all three embryonic layers (i.e. endo-, ecto- and mesoderm).
The few groups reporting success have typically confirmed endodermal
potential using hepatic differentiation. We report differentiation
of human UCB-derived multipotent stem cells, termed multilineage
progenitor cells (MLPC), into respiratory epithelial cells (i.e.
type II alveolar cells).
METHODS: Using a cell separation medium (PrepaCyte-MLPC; BioE Inc.)
and plastic adherence, MLPC were isolated from four of 16 UCB units
(American Red Cross) and expanded. Cultures were grown to 80% confluence
in mesenchymal stromal cell growth medium (MSCGM; Cambrex BioScience)
prior to addition of small airway growth medium (SAGM; Cambrex BioScience),
an airway maintenance medium. Following a 3-8-day culture, cells
were characterized by light microscopy, transmission electron microscopy,
immunofluorescence and reverse transcriptase (RT)-PCR.
RESULTS: MLPC were successfully differentiated into type II alveolar
cells (four of four mixed lines; two of two clonal lines). Differentiated
cells were characterized by epithelioid morphology with lamellar
bodies. Both immunofluorescence and RT-PCR confirmed the presence
of surfactant protein C, a protein highly specific for type II cells.
DISCUSSION: MLPC were isolated, expanded and then differentiated
into respiratory epithelial cells using an off-the-shelf medium
designed for maintenance of fully differentiated respiratory epithelial
cells. To the best of our knowledge, this is the first time human
non-embryonic multipotent stem cells have been differentiated into
type II alveolar cells. Further studies to evaluate the possibilities
for both research and therapeutic applications are necessary.
Complete repair of dystrophic skeletal muscle by mesoangioblasts
with enhanced migration ability.
Galvez BG, et al.
J Cell Biol. 2006 Jul 17;174(2):231-43. Epub 2006 Jul 10.
Abstract: Efficient delivery of cells to target tissues is a major
problem in cell therapy. We report that enhancing delivery of mesoangioblasts
leads to a complete reconstitution of downstream skeletal muscles
in a mouse model of severe muscular dystrophy (alpha-sarcoglycan
ko). Mesoangioblasts, vessel-associated stem cells, were exposed
to several cytokines, among which stromal- derived factor (SDF)
1 or tumor necrosis factor (TNF) alpha were the most potent in enhancing
transmigration in vitro and migration into dystrophic muscle in
vivo. Transient expression of alpha4 integrins or L-selectin also
increased several fold migration both in vitro and in vivo. Therefore,
combined pretreatment with SDF-1 or TNF-alpha and expression of
alpha4 integrin leads to massive colonization (>50%) followed
by reconstitution of >80% of alpha-sarcoglycan-expressing fibers,
with a fivefold increase in efficiency in comparison with control
cells. This study defines the requirements for efficient engraftment
of mesoangioblasts and offers a new potent tool to optimize future
cell therapy protocols for muscular dystrophies.
Bone marrow stromal cells can achieve cure of chronic
paraplegic rats: functional and morphological outcome one year after
Zurita M, Vaquero J.
Neurosci Lett. 2006 Jul 10;402(1-2):51-6. Epub 2006 May 19.
Abstract: Chronic paraplegia resulting from severe spinal cord injury
(SCI) is considered to be an irreversible condition. Nevertheless,
recent studies utilizing adult stem cells appear to offer promise
in the treatment of this and other neurological diseases. Here,
we show that progressive functional motor recovery is achieved over
the course of the year following the administration of bone marrow
stromal cells (BMSC) in traumatic central spinal cord cavities of
adult rats with chronic paraplegia. At this time, functional recovery
is almost complete and associated with evident nervous tissue regeneration
in the previously injured spinal cord.
Maturation of tissue engineered cartilage implanted
in injured and osteoarthritic human knees.
Hollander AP, et al.
Tissue Eng. 2006 Jul;12(7):1787-98.
Abstract: The regeneration of damaged organs requires that engineered
tissues mature when implanted at sites of injury or disease. We
have used new analytic techniques to determine the extent of tissue
regeneration after treatment of knee injury patients with a novel
cartilage tissue engineering therapy and the effect of pre-existing
osteoarthritis on the regeneration process. We treated 23 patients,
with a mean age of 35.6 years, presenting with knee articular cartilage
defects 1.5 cm2 to 11.25 cm2 (mean, 5.0 cm2) in area. Nine of the
patients had X-ray evidence of osteoarthritis. Chondrocytes were
isolated from healthy cartilage removed at arthroscopy. The cells
were cultured for 14 days, seeded onto esterified hyaluronic acid
scaffolds (Hyalograft C), and grown for a further 14 days before
implantation. A second-look biopsy was taken from each patient after
6 to 30 months (mean, 16 months). After standard histological analysis,
uncut tissue was further analyzed using a newly developed biochemical
protocol involving digestion with trypsin and specific, quantitative
assays for type II collagen, type I collagen, and proteoglycan,
as well as mature and immature collagen crosslinks. Cartilage regeneration
was observed as early as 11 months after implantation and in 10
out of 23 patients. Tissue regeneration was found even when implants
were placed in joints that had already progressed to osteoarthrosis.
Cartilage injuries can be effectively repaired using tissue engineering,
and osteoarthritis does not inhibit the regeneration process.
Characterization and clinical application of human
CD34+ stem/progenitor cell populations mobilized into the blood
by granulocyte colony-stimulating factor.
Gordon MY, et al.
Stem Cells. 2006 Jul;24(7):1822-30. Epub 2006 Mar 23.
Abstract: A phase I study was performed to determine the safety
and tolerability of injecting autologous CD34(+) cells into five
patients with liver insufficiency. The study was based on the hypothesis
that the CD34(+) cell population in granulocyte colony-stimulating
factor (G-CSF)-mobilized blood contains a subpopulation of cells
with the potential for regenerating damaged tissue. We separated
a candidate CD34(+) stem cell population from the majority of the
CD34(+) cells (99%) by adherence to tissue culture plastic. The
adherent and nonadherent CD34(+) cells were distinct in morphology,
immunophenotype, and gene expression profile. Reverse transcription-polymerase
chain reaction-based gene expression analysis indicated that the
adherent CD34(+) cells had the potential to express determinants
consistent with liver, pancreas, heart, muscle, and nerve cell differentiation
as well as hematopoiesis. Overall, the characteristics of the adherent
CD34(+) cells identify them as a separate putative stem/progenitor
cell population. In culture, they produced a population of cells
exhibiting diverse morphologies and expressing genes corresponding
to multiple tissue types. Encouraged by this evidence that the CD34(+)
cell population contains cells with the potential to form hepatocyte-like
cells, we gave G-CSF to five patients with liver insufficiency to
mobilize their stem cells for collection by leukapheresis. Between
1 x 10(6) and 2 x 10(8) CD34(+) cells were injected into the portal
vein (three patients) or hepatic artery (two patients). No complications
or specific side effects related to the procedure were observed.
Three of the five patients showed improvement in serum bilirubin
and four of five in serum albumin. These observations warrant further
Regeneration and transdifferentiation potential of
muscle-derived stem cells propagated as myospheres.
Sarig R, et al.
Stem Cells. 2006 Jul;24(7):1769-78. Epub 2006 Mar 30.
Abstract: We have isolated from mouse skeletal muscle a subpopulation
of slow adherent myogenic cells that can proliferate for at least
several months as suspended clusters of cells (myospheres). In the
appropriate conditions, the myospheres adhere to the plate, spread
out, and form a monolayer of MyoD(+) cells. Unlike previously described
myogenic cell lines, most of the myosphere cells differentiate,
without cell fusion, into thin mononucleated contractile fibers,
which express myogenin and skeletal muscle myosin heavy chain. The
presence of Pax-7 in a significant proportion of these cells suggests
that they originate from satellite cells. The addition of leukemia
inhibitory factor to the growth medium of the myospheres enhances
proliferation and dramatically increases the proportion of cells
expressing Sca-1, which is expressed by several types of stem cells.
The capacity of myosphere cells to transdifferentiate to other mesodermal
cell lineages was examined. Exposure of cloned myosphere cells to
bone morphogenetic protein resulted in suppression of myogenic differentiation
and induction of osteogenic markers such as alkaline phosphatase
and osteocalcin. These cells also sporadically differentiated to
adipocytes. Myosphere cells could not, so far, be induced to transdifferentiate
to hematopoietic cells. When inoculated into injured muscle, myosphere-derived
cells participated in regeneration, forming multinucleated cross-striated
mature fibers. This suggests a potential medical application.
In vitro differentiation of human placenta-derived
multipotent cells into hepatocyte-like cells.
Chien CC, et al.
Stem Cells. 2006 Jul;24(7):1759-68.
Abstract: Multipotent cells isolated from human term placenta (placenta-derived
multipotent cells [PDMCs]) have been known to be able to differentiate
into mesodermal lineage cells, including adipocytes and osteoclasts.
The low infection rate and young age of placenta compared with other
tissue origins of adult stem cells make theses cells attractive
target for cell-based therapy. However, the differentiation potential
of PDMCs toward hepatic cells has not been evaluated yet. In this
study, we cultivated PDMCs with hepatic differentiation medium to
evaluate the ability of these cells in differentiating toward hepatic
cells. After treatment, the morphologies of differentiated PDMCs
changed to polygonal epithelial cell-like. The differentiated cells
not only show the hepatocyte-like morphologies but also express
hepatocyte-specific markers, including albumin and cytokeratin 18.
The bioactivity assays revealed that these hepatocyte-like cells
could uptake lipoprotein and store glycogen. Furthermore, the addition
of rifampicin increased the gene expression of CYP3A4, which is
similar with the activities of human liver cells. According to our
previous results, PDMCs were capable of differentiating into mesodermal
and ectodermal lineage cells. Our results indicate that PDMCs can
differentiate into three germ layer cells, which is similar to embryonic
stem cells. In conclusion, placenta might be an easily accessible
source for progenitor cells that are capable of differentiating
toward hepatocyte-like cells in vitro.
The defined combination of growth factors controls
generation of long-term-replicating islet progenitor-like cells
from cultures of adult mouse pancreas.
Ta M, et al.
Stem Cells. 2006 Jul;24(7):1738-49. Epub 2006 Mar 23.
Abstract: Application of pancreatic islet transplantation to treatment
of diabetes is severely hampered by the inadequate islet supply.
This problem could in principle be overcome by generating islet
cells from adult pancreas in vitro. Although it is possible to obtain
replicating cells from cultures of adult pancreas, these cells,
when significantly expanded in vitro, progressively lose pancreatic-specific
gene expression, including that of a "master" homeobox
transcription factor Pdx1. Here we show for the first time that
long-term proliferating islet progenitor-like cells (IPLCs) stably
expressing high levels of Pdx1 and other genes that control early
pancreatic development can be derived from cultures of adult mouse
pancreas under serum-free defined culture conditions. Moreover,
we show that cells derived thus can be maintained in continuous
culture for at least 6 months without any substantial loss of early
pancreatic phenotype. Upon growth factor withdrawal, the IPLCs organize
into cell clusters and undergo endocrine differentiation of various
degrees in a line-dependent manner. We propose that our experimental
strategy will provide a framework for developing efficient approaches
for ex vivo expansion of islet cell mass.
Allogeneic haematopoietic stem cell transplantation
for metastatic renal carcinoma in Europe.
Barkholt L, et al.
Ann Oncol. 2006 Jul;17(7):1134-40. Epub 2006 Apr 28.
BACKGROUND: An allogeneic antitumour effect has been reported for
various cancers. We evaluated the experience of allogeneic haematopoietic
stem cell transplantation (HSCT) for renal cell carcinoma (RCC)
in 124 patients from 21 European centres.
PATIENTS AND METHODS: Reduced intensity conditioning and peripheral
blood stem cells from an HLA-identical sibling (n = 106), a mismatched
related (n = 5), or an unrelated (n = 13) donor were used. Immunosuppression
was cyclosporine alone, or combined with methotrexate or mycophenolate
mofetil. Donor lymphocyte infusions (DLI) were given to 42 patients.
The median follow-up was 15 (range 3-41) months.
RESULTS: All but three patients engrafted. The cumulative incidence
of moderate to severe, grades II-IV acute GVHD was 40% and for chronic
GVHD it was 33%. Transplant-related mortality was 16% at one year.
Complete (n = 4) or partial (n = 24) responses, median 150 (range
42-600) days post-transplant, were associated with time from diagnosis
to HSCT, mismatched donor and acute GVHD II-IV. Factors associated
with survival included chronic GVHD (hazards ratio, HR 4.12, P <
0.001), DLI (HR 3.39, P < 0.001), <3 metastatic sites (HR
2.61, P = 0.002) and a Karnofsky score >70 (HR 2.33, P = 0.03).
Patients (n = 17) with chronic GVHD and given DLI had a 2-year survival
CONCLUSION: Patients with metastatic RCC, less than three metastatic
locations and a Karnofsky score >70% can be considered for HSCT.
Posttransplant DLI and limited chronic GVHD improved the patient
Derivation of male germ cells from bone marrow stem
Nayernia K, et al.
Lab Invest. 2006 Jul;86(7):654-63. Epub 2006 May 1.
Abstract: Recent studies have demonstrated that somatic stem cells
have a more flexible potential than expected, whether put into tissue
or cultured under different conditions. Bone marrow (BM)-derived
stem cells can transdifferentiate into multilineage cells, such
as muscle of mesoderm, lung and liver of endoderm, and brain and
skin of ectoderm origin. Here we show that BM stem cells are able
to transdifferentiate into male germ cells. For derivation of male
germ cells from adult BM stem (BMS) cells, we used the Stra8-enhanced
green fluoresence protein (EGFP) transgenic mouse line expressing
EGFP specifically in male germ cells. BMS cell-derived germ cells
expressed the known molecular markers of primordial germ cells,
such as fragilis, stella, Rnf17, Mvh and Oct4; as well as molecular
markers of spermatogonial stem cells and spermatogonia including
Rbm, c-Kit, Tex18, Stra8, Piwil2, Dazl, Hsp90alpha, beta1- and alpha6-integrins.
Our ability to derive male germ cells from BMS cells reveals novel
aspects of germ cell development and opens the possibilities for
use of these cells in reproductive medicine.
Living autologous heart valves engineered from human
prenatally harvested progenitors.
Schmidt D, et al.
Circulation. 2006 Jul 4;114(1 Suppl):I125-31.
BACKGROUND: Heart valve tissue engineering is a promising strategy
to overcome the lack of autologous growing replacements, particularly
for the repair of congenital malformations. Here, we present a novel
concept using human prenatal progenitor cells as new and exclusive
cell source to generate autologous implants ready for use at birth.
METHODS AND RESULTS: Human fetal mesenchymal progenitors were isolated
from routinely sampled prenatal chorionic villus specimens and expanded
in vitro. A portion was cryopreserved. After phenotyping and genotyping,
cells were seeded onto synthetic biodegradable leaflet scaffolds
(n=12) and conditioned in a bioreactor. After 21 days, leaflets
were endothelialized with umbilical cord blood-derived endothelial
progenitor cells and conditioned for additional 7 days. Resulting
tissues were analyzed by histology, immunohistochemistry, biochemistry
(amounts of extracellular matrix, DNA), mechanical testing, and
scanning electron microscopy (SEM) and were compared with native
neonatal heart valve leaflets. Fresh and cryopreserved cells showed
comparable myofibroblast-like phenotypes. Genotyping confirmed their
fetal origin. Neo-tissues exhibited organization, cell phenotypes,
extracellular matrix production, and DNA content comparable to their
native counterparts. Leaflet surfaces were covered with functional
endothelia. SEM showed cellular distribution throughout the polymer
and smooth surfaces. Mechanical profiles approximated those of native
CONCLUSIONS: Prenatal fetal progenitors obtained from routine chorionic
villus sampling were successfully used as an exclusive, new cell
source for the engineering of living heart valve leaflets. This
concept may enable autologous replacements with growth potential
ready for use at birth. Combined with the use of cell banking technology,
this approach may be applied also for postnatal applications.
Autologous human tissue-engineered heart valves: prospects
for systemic application.
Mol A, et al.
Circulation. 2006 Jul 4;114(1 Suppl):I152-8.
BACKGROUND: Tissue engineering represents a promising approach for
the development of living heart valve replacements. In vivo animal
studies of tissue-engineered autologous heart valves have focused
on pulmonary valve replacements, leaving the challenge to tissue
engineer heart valves suitable for systemic application using human
METHODS AND RESULTS: Tissue-engineered human heart valves were analyzed
up to 4 weeks and conditioning using bioreactors was compared with
static culturing. Tissue formation and mechanical properties increased
with time and when using conditioning. Organization of the tissue,
in terms of anisotropic properties, increased when conditioning
was dynamic in nature. Exposure of the valves to physiological aortic
valve flow demonstrated proper opening motion. Closure dynamics
were suboptimal, most likely caused by the lower degree of anisotropy
when compared with native aortic valve leaflets.
CONCLUSIONS: This study presents autologous tissue-engineered heart
valves based on human saphenous vein cells and a rapid degrading
synthetic scaffold. Tissue properties and mechanical behavior might
allow for use as living aortic valve replacements.
Autologous hematopoietic stem cell transplantation
for older patients with relapsed non-Hodgkin's lymphoma.
Buadi FK, et al.
Bone Marrow Transplant. 2006 Jun;37(11):1017-22.
Abstract: To evaluate autologous stem cell transplant (ASCT) in
older patients with intermediate grade non-Hodgkin's lymphoma (NHL),
the Mayo Clinic Rochester BMT database was reviewed for all patients
60 years of age and older who received ASCT for NHL between September
1995 and February 2003. Factors evaluated included treatment-related
mortality (TRM), event-free survival (EFS) and overall survival
(OS). Ninety-three patients were identified, including twenty-four
(26%) over the age of 70 years. Treatment-related mortality (5.4%)
was not significantly different when compared to a younger cohort
(2.2%). At a median follow-up of 14 months (0.6-87.6 months), the
estimated median survival is 25 months (95% confidence interval
(CI) 12-38) in the older group compared to 56 months (95% CI 37-75)
(P=0.037) in the younger group. The estimated 4-year EFS was 38%
for the older group compared to 42% in the younger cohort (P=0.1).
By multivariate analysis, the only factor found to influence survival
in the older group was age-adjusted International Prognostic Index
at relapse, 0-1 better than 2-3 (P=0.03). Autologous stem-cell transplant
can be safely performed in patients 60 years or older with chemotherapy
sensitive relapsed or first partial remission NHL. The outcome may
not be different from that of younger patients in terms of TRM and
Isolation of a novel population of multipotent adult
stem cells from human hair follicles.
Yu H, et al.
Am J Pathol. 2006 Jun;168(6):1879-88.
Abstract: Hair follicles are known to contain a well-characterized
niche for adult stem cells: the bulge, which contains epithelial
and melanocytic stem cells. Using human embryonic stem cell culture
conditions, we isolated a population of adult stem cells from human
hair follicles that are distinctively different from known epithelial
or melanocytic stem cells. These cells do not express squamous or
melanocytic markers but express neural crest and neuron stem cell
markers as well as the embryonic stem cell transcription factors
Nanog and Oct4. These precursor cells proliferate as spheres, are
capable of self-renewal, and can differentiate into multiple lineages.
Differentiated cells not only acquire lineage-specific markers but
also demonstrate appropriate functions in ex vivo conditions. Most
of the Oct4-positive cells in human skin were located in the area
highlighted by cytokeratin 15 staining in vivo. Our data suggest
that human embryonic stem cell medium can be used to isolate and
expand human adult stem cells. Using this method, we isolated a
novel population of multipotent adult stem cells from human hair
follicles, and these cells appear to be located in the bulge area.
Human hair follicles may provide an accessible, autologous source
of adult stem cells for therapeutic application.
Successful stem cell therapy using umbilical cord
blood-derived multipotent stem cells for Buerger's disease and ischemic
limb disease animal model.
Kim SW, et al.
Stem Cells. 2006 Jun;24(6):1620-6. Epub 2006 Feb 23.
Abstract: Buerger's disease, also known as thromboangiitis obliterans,
is a nonatherosclerotic, inflammatory, vasoocclusive disease. It
is characterized pathologically as a panangiitis of medium and small
blood vessels, including both arteries and adjacent veins, especially
the distal extremities (the feet and the hands). There is no curative
medication or surgery for this disease. In the present study, we
transplanted human leukocyte antigen-matched human umbilical cord
blood (UCB)-derived mesenchymal stem cells (MSCs) into four men
with Buerger's disease who had already received medical treatment
and surgical therapies. After the stem cell transplantation, ischemic
rest pain suddenly disappeared from their affected extremities.
The necrotic skin lesions were healed within 4 weeks. In the follow-up
angiography, digital capillaries were increased in number and size.
In addition, vascular resistance in the affected extremities, compared
with the preoperative examination, was markedly decreased due to
improvement of the peripheral circulation. Because an animal model
of Buerger's disease is absent and also to understand human results,
we transplanted human UCB-derived MSCs to athymic nude mice with
hind limb ischemia by femoral artery ligation. Up to 60% of the
hind limbs were salvaged in the femoral artery-ligated animals.
By in situ hybridization, the human UCB-derived MSCs were detected
in the arterial walls of the ischemic hind limb in the treated group.
Therefore, it is suggested that human UCB-derived MSC transplantation
may be a new and useful therapeutic armament for Buerger's disease
and similar ischemic diseases.
Formation of a functional thymus initiated by a postnatal
epithelial progenitor cell.
Bleul CC, et al.
Nature. 2006 Jun 22;441(7096):992-6.
Abstract: The thymus is essential for the generation of self-tolerant
effector and regulatory T cells. Intrathymic T-cell development
requires an intact stromal microenvironment, of which thymic epithelial
cells (TECs) constitute a major part. For instance, cell-autonomous
genetic defects of forkhead box N1 (Foxn1) and autoimmune regulator
(Aire) in thymic epithelial cells cause primary immunodeficiency
and autoimmunity, respectively. During development, the thymic epithelial
rudiment gives rise to two major compartments, the cortex and medulla.
Cortical TECs positively select T cells, whereas medullary TECs
are involved in negative selection of potentially autoreactive T
cells. It has long been unclear whether these two morphologically
and functionally distinct types of epithelial cells arise from a
common bi-potent progenitor cell and whether such progenitors are
still present in the postnatal period. Here, using in vivo cell
lineage analysis in mice, we demonstrate the presence of a common
progenitor of cortical and medullary TECs after birth. To probe
the function of postnatal progenitors, a conditional mutant allele
of Foxn1 was reverted to wild-type function in single epithelial
cells in vivo. This led to the formation of small thymic lobules
containing both cortical and medullary areas that supported normal
thymopoiesis. Thus, single epithelial progenitor cells can give
rise to a complete and functional thymic microenvironment, suggesting
that cell-based therapies could be developed for thymus disorders.
Stem cell niches in the adult mouse heart.
Urbanek K, et al.
Proc Natl Acad Sci U S A. 2006 Jun 13;103(24):9226-31. Epub 2006
Abstract: Cardiac stem cells (CSCs) have been identified in the
adult heart, but the microenvironment that protects the slow-cycling,
undifferentiated, and self-renewing CSCs remains to be determined.
We report that the myocardium possesses interstitial structures
with the architectural organization of stem cell niches that harbor
long-term BrdU-retaining cells. The recognition of long-term label-retaining
cells provides functional evidence of resident CSCs in the myocardium,
indicating that the heart is an organ regulated by a stem cell compartment.
Cardiac niches contain CSCs and lineage-committed cells, which are
connected to supporting cells represented by myocytes and fibroblasts.
Connexins and cadherins form gap and adherens junctions at the interface
of CSCs-lineage-committed cells and supporting cells. The undifferentiated
state of CSCs is coupled with the expression of alpha(4)-integrin,
which colocalizes with the alpha(2)-chain of laminin and fibronectin.
CSCs divide symmetrically and asymmetrically, but asymmetric division
predominates, and the replicating CSC gives rise to one daughter
CSC and one daughter committed cell. By this mechanism of growth
kinetics, the pool of primitive CSCs is preserved, and a myocyte
progeny is generated together with endothelial and smooth muscle
cells. Thus, CSCs regulate myocyte turnover that is heterogeneous
across the heart, faster at the apex and atria, and slower at the
base-midregion of the ventricle.
Skin-derived precursors generate myelinating Schwann
cells for the injured and dysmyelinated nervous system.
McKenzie IA, et al.
J Neurosci. 2006 Jun 14;26(24):6651-60.
Abstract: Although neural stem cells hold considerable promise for
treatment of the injured or degenerating nervous system, their current
human sources are embryonic stem cells and fetally derived neural
tissue. Here, we asked whether rodent and human skin-derived precursors
(SKPs), neural crest-related precursors found in neonatal dermis,
represent a source of functional, myelinating Schwann cells. Specifically,
cultured SKPs responded to neural crest cues such as neuregulins
to generate Schwann cells, and these Schwann cells proliferated
and induced myelin proteins when in contact with sensory neuron
axons in culture. Similar results were obtained in vivo; 6 weeks
after transplantation of naive SKPs or SKP-derived Schwann cells
into the injured peripheral nerve of wild-type or shiverer mutant
mice (which are genetically deficient in myelin basic protein),
the majority of SKP-derived cells had associated with and myelinated
axons. Naive rodent or human SKPs also generated Schwann cells that
myelinated CNS axons when transplanted into the dysmyelinated brain
of neonatal shiverer mice. Thus, neonatal SKPs generate functional
neural progeny in response to appropriate neural crest cues and,
in so doing, provide a highly accessible source of myelinating cells
for treatment of nervous system injury, congenital leukodystrophies,
and dysmyelinating disorders.
Angiogenesis facilitated by autologous whole bone
marrow stem cell transplantation for Buerger's disease.
Kim DI, et al.
Stem Cells. 2006 May;24(5):1194-200. Epub 2006 Jan 26.
Abstract: We hypothesized that angiogenesis can be triggered by
autologous whole bone marrow stem cell transplantation. Twenty-seven
patients (34 lower limbs) with Buerger's disease, who were not candidates
for surgical revascularization or radiologic intervention, were
enrolled in this study. Six sites of the tibia bone were fenestrated
using a 2.5-mm-diameter screw under fluoroscopic guidance. Clinical
status and outcome were determined using the "Recommended Standards
for Reports." To mobilize endothelial progenitor cells (EPCs)
from bone marrow, recombinant human granulocyte colony-stimulating
factor (r-HuG-CSF) was injected subcutaneously as a dose of 75 microg,
preoperatively. During the follow-up period (19.1 +/- 3.5 months),
one limb showed a markedly improved outcome (+3), and 26 limbs showed
a moderately improved outcome (+2). Thirteen limbs among 17 limbs
with nonhealing ulcers healed. Postoperative angiograms were obtained
for 22 limbs. Two limbs showed marked (+3), five limbs moderate
(+2), and nine limbs slight (+1) collateral development. However,
six limbs showed no collateral development (0). Peripheral blood
and bone marrow samples were analyzed for CD34 and CD133 molecules
to enumerate potential EPCs, and EPC numbers were found to be increased
in peripheral blood and in bone marrow after r-HuG-CSF injection.
In conclusion, the transplantation of autologous whole BMCs by fenestration
of the tibia bone represents a simple, safe, and effective means
of inducing therapeutic angiogenesis in patients with Buerger's
Transplantation of human hematopoietic stem cells
into ischemic and growing kidneys suggests a role in vasculogenesis
but not tubulogenesis.
Dekel B, et al.
Stem Cells. 2006 May;24(5):1185-93. Epub 2006 Jan 12.
Abstract: Transplantation of murine bone marrow-derived stem cells
has been reported recently to promote regeneration of the injured
kidney. We investigated the potential of human adult CD34(+) progenitor
cells to undergo renal differentiation once xenotransplanted into
ischemic and developing kidneys. Immunostaining with human-specific
antibodies for tubular cells (broad-spectrum cytokeratin), endothelial
cells (CD31, PECAM), stromal cells (vimentin), and hematopoietic
cells (pan-leukocyte CD45) demonstrated that although kidney ischemia
enhanced engraftment of human cells, they were mostly hematopoietic
cells (CD45(+)) residing in the interstitial spaces. Few other engrafted
cells demonstrated an endothelial phenotype (human CD31(+)in morphologically
appearing peritubular capillaries), but no evidence of tubular or
stromal cells of human origin was found. Upregulation of SDF1 and
HIF1 transcript levels in the ischemic kidneys might explain the
diffuse engraftment of CD45(+)cells following injury. Similarly,
when embryonic kidneys rudiments were co-transplanted with human
CD34(+)cells in mice, we found both human CD45(+)and CD31(+)cells
in the periphery of the developing renal grafts, whereas parenchymal
elements failed to stain. In addition, human CD34(+)cells had no
effect on kidney growth and differentiation. This first demonstration
of human CD34(+)stem cell transplantation into injured and developing
kidneys indicates that these cells do not readily acquire a tubular
phenotype and are restricted mainly to hematopoietic and, to a lesser
extent, to endothelial lineages. Efforts should be made to identify
additional stem cell sources applicable for kidney growth and regeneration.
Bone marrow-derived cells home to and regenerate retinal
pigment epithelium after injury.
Harris JR, et al.
Invest Ophthalmol Vis Sci. 2006 May;47(5):2108-13.
PURPOSE: To determine whether hematopoietic stem and progenitor
cells (HSCs/HPCs) can home to and regenerate the retinal pigment
epithelium (RPE) after induced injury.
METHODS: Enriched HSCs/HPCs from green fluorescent protein (gfp)
transgenic mice were transplanted into irradiated recipient mice
to track bone marrow-derived cells. Physical damage was induced
by breaching Bruch's membrane and inducing vascular endothelial
growth factor A (VEGFa) expression to promote neovascularization.
RPE damage was also induced by sodium iodate injection (40 mg/kg)
into wild-type or albino C57Bl/6 mice. Cell morphology, gfp expression,
the presence of the Y chromosome, and the presence of melanosomes
were used to determine whether the injured RPE was being repaired
by the donor bone marrow.
RESULTS: Injury to the RPE recruits HSC/HPC-derived cells to incorporate
into the RPE layer and differentiate into an RPE phenotype. A portion
of the HSCs/HPCs adopt RPE morphology, express melanosomes, and
integrate into the RPE without cell fusion.
CONCLUSIONS: HSCs/HPCs can migrate to the RPE layer after physical
or chemical injury and regenerate a portion of the damaged cell
Unilateral intraputaminal glial cell line-derived
neurotrophic factor in patients with Parkinson disease: response
to 1 year each of treatment and withdrawal.
Slevin JT, et al.
Neurosurg Focus. 2006 May 15;20(5):E1.
OBJECT: Glial cell line-derived neurotrophic factor (GDNF) infused
unilaterally into the putamen for 6 months was previously shown
to improve motor functions and quality of life measures significantly
in 10 patients with Parkinson disease (PD) in a Phase I trial. In
this study the authors report the safety and efficacy of continuous
treatment for 1 year or more. After the trial was halted by the
sponsor, the patients were monitored for an additional year to evaluate
the effects of drug withdrawal.
METHODS: During the extended study, patients received unilateral
intraputaminal infusion of 30 mg/day GDNF at a basal infusion rate
supplemented with pulsed boluses every 6 hours at a convection-enhanced
delivery rate to increase tissue penetration of the protein. When
the study was stopped, the delivery system was reprogrammed to deliver
sterile saline at the basal infusion rate of 2 ml/hour. The Unified
PD Rating Scale (UPDRS) total scores after 1 year of therapy were
improved by 42 and 38%, respectively, in the "off" and
"on" states. Motor UPDRS scores were also improved: 45
and 39% in the off and on conditions, respectively. Benefits from
treatment were lost by 9 to 12 months after GDNF infusion was halted.
At that time, the patients had returned to their baseline UPDRS
scores and required higher levels of conventional antiparkinsonian
drugs to treat symptoms. After 11 months of treatment, the delivery
system had to be removed in one patient because of the risk of infection.
In seven patients antibodies to GDNF developed, with no evidence
of clinical sequelae. There was also no evidence of GDNF-induced
cerebellar toxicity, as evaluated using magnetic resonance imaging
analysis and clinical testing.
CONCLUSIONS: Unilateral administration of GDNF results in significant,
sustained bilateral benefits. These improvements are lost within
9 months after drug withdrawal. Safety concerns with GDNF therapy
can be closely monitored and managed.
Targeting of melanoma brain metastases using engineered
neural stem/progenitor cells.
Aboody KS, et al.
Neuro-oncol. 2006 Apr;8(2):119-26. Epub 2006 Mar 8.
Abstract: Brain metastases are an increasingly frequent and serious
clinical problem for cancer patients, especially those with advanced
melanoma. Given the extensive tropism of neural stem/progenitor
cells (NSPCs) for pathological areas in the central nervous system,
we expanded investigations to determine whether NSPCs could also
target multiple sites of brain metastases in a syngeneic experimental
melanoma model. Using cytosine deaminase-expressing NSPCs (CD-NSPCs)
and systemic 5-fluorocytosine (5-FC) pro-drug administration, we
explored their potential as a cell-based targeted drug delivery
system to disseminated brain metastases. Our results indicate a
strong tropism of NSPCs for intracerebral melanoma metastases. Furthermore,
in our therapeutic paradigm, animals with established melanoma brain
metastasis received intracranial implantation of CD-NSPCs followed
by systemic 5-FC treatment, resulting in a significant (71%) reduction
in tumor burden. These data provide proof of principle for the use
of NSPCs for targeted delivery of therapeutic gene products to melanoma
Tissue-engineered autologous bladders for patients
Atala A, et al.
Lancet. 2006 Apr 15;367(9518):1241-6.
BACKGROUND: Patients with end-stage bladder disease can be treated
with cystoplasty using gastrointestinal segments. The presence of
such segments in the urinary tract has been associated with many
complications. We explored an alternative approach using autologous
engineered bladder tissues for reconstruction.
METHODS: Seven patients with myelomeningocele, aged 4-19 years,
with high-pressure or poorly compliant bladders, were identified
as candidates for cystoplasty. A bladder biopsy was obtained from
each patient. Urothelial and muscle cells were grown in culture,
and seeded on a biodegradable bladder-shaped scaffold made of collagen,
or a composite of collagen and polyglycolic acid. About 7 weeks
after the biopsy, the autologous engineered bladder constructs were
used for reconstruction and implanted either with or without an
omental wrap. Serial urodynamics, cystograms, ultrasounds, bladder
biopsies, and serum analyses were done.
RESULTS: Follow-up range was 22-61 months (mean 46 months). Post-operatively,
the mean bladder leak point pressure decrease at capacity, and the
volume and compliance increase was greatest in the composite engineered
bladders with an omental wrap (56%, 1.58-fold, and 2.79-fold, respectively).
Bowel function returned promptly after surgery. No metabolic consequences
were noted, urinary calculi did not form, mucus production was normal,
and renal function was preserved. The engineered bladder biopsies
showed an adequate structural architecture and phenotype.
CONCLUSIONS: Engineered bladder tissues, created with autologous
cells seeded on collagen-polyglycolic acid scaffolds, and wrapped
in omentum after implantation, can be used in patients who need
Granulocyte colony-stimulating factor for acute ischemic
stroke: a randomized controlled trial.
Shyu WC, et al.
CMAJ. 2006 Mar 28;174(7):927-33. Epub 2006 Mar 3.
BACKGROUND: Because granulocyte colony-stimulating factor (G-CSF)
has anti-inflammatory and neuroprotective properties and is known
to mobilize stem cells, it may be useful in the treatment of acute
ischemic stroke. We sought to examine the feasibility, safety and
efficacy of using G-CSF to treat acute stroke.
METHODS: We conducted a randomized, blinded controlled trial involving
10 patients with acute cerebral infarction (middle cerebral artery
territory as documented by the admission MRI) who presented within
7 days of onset and whose scores on the National Institutes of Health
Stroke Scale (NIHSS) were between 9 and 20. Patients were assigned
to either G-CSF therapy or usual care. The G-CSF group (n = 7) received
subcutaneous G-CSF injections (15 microg/kg per day) for 5 days.
The primary outcome was percentage changes between baseline and
12-month follow-up in mean group scores on 4 clinical scales: the
NIHSS, European Stroke Scale (ESS), ESS Motor Subscale (EMS) and
Barthel Index (BI). We also assessed neurologic functioning using
PET to measure cerebral uptake of fluorodeoxyglucose in the cortical
areas surrounding the ischemic core.
RESULTS: All of the patients completed the 5-day course of treatment,
and none were lost to follow-up. No severe adverse effects were
seen in patients receiving G-CSF. There was greater improvement
in neurologic functioning between baseline and 12-month follow-up
in the G-CSF group than in the control group (NIHSS: 59% change
in the mean G-CSF group score v. 36% in the mean control group score,
ESS: 33% v. 20%, EMS: 106% v. 58%, BI: 120% v. 60%). Although at
12 months there was no difference between the 2 groups in cerebral
uptake of fluorodeoxyglucose in the ischemic core, uptake in the
area surrounding the core was significantly improved in the G-CSF
group compared with the control group. There was positive correlation
between metabolic activity and EMS score following simple linear
INTERPRETATION: Our preliminary evidence suggests that using G-CSF
as therapy for acute stroke is safe and feasible and leads to improved
Delayed transplantation of adult neural precursor
cells promotes remyelination and functional neurological recovery
after spinal cord injury.
Karimi-Abdolrezaee S, et al.
J Neurosci. 2006 Mar 29;26(13):3377-89.
Abstract: Spinal cord injury (SCI) results in loss of oligodendrocytes
demyelination of surviving axons and severe functional impairment.
Spontaneous remyelination is limited. Thus, cell replacement therapy
is an attractive approach for myelin repair. In this study, we transplanted
adult brain-derived neural precursor cells (NPCs) isolated from
yellow fluorescent protein-expressing transgenic mice into the injured
spinal cord of adult rats at 2 and 8 weeks after injury, which represents
the subacute and chronic phases of SCI. A combination of growth
factors, the anti-inflammatory drug minocycline, and cyclosporine
A immunosuppression was used to enhance the survival of transplanted
adult NPCs. Our results show the presence of a substantial number
of surviving NPCs in the injured spinal cord up to 10 weeks after
transplantation at the subacute stage of SCI. In contrast, cell
survival was poor after transplantation into chronic lesions. After
subacute transplantation, grafted cells migrated >5 mm rostrally
and caudally. The surviving NPCs integrated principally along white-matter
tracts and displayed close contact with the host axons and glial
cells. Approximately 50% of grafted cells formed either oligodendroglial
precursor cells or mature oligodendrocytes. NPC-derived oligodendrocytes
expressed myelin basic protein and ensheathed the axons. We also
observed that injured rats receiving NPC transplants had improved
functional recovery as assessed by the Basso, Beattie, and Bresnahan
Locomotor Rating Scale and grid-walk and footprint analyses. Our
data provide strong evidence in support of the feasibility of adult
NPCs for cell-based remyelination after SCI.
Human umbilical cord matrix stem cells: preliminary
characterization and effect of transplantation in a rodent model
of Parkinson's disease.
Weiss ML, et al.
Stem Cells. 2006 Mar;24(3):781-92. Epub 2005 Oct 13.
Abstract: The umbilical cord contains an inexhaustible, noncontroversial
source of stem cells for therapy. In the U.S., stem cells found
in the umbilical cord are routinely placed into bio-hazardous waste
after birth. Here, stem cells derived from human umbilical cord
Wharton's Jelly, called umbilical cord matrix stem (UCMS) cells,
are characterized. UCMS cells have several properties that make
them of interest as a source of cells for therapeutic use. For example,
they 1) can be isolated in large numbers, 2) are negative for CD34
and CD45, 3) grow robustly and can be frozen/thawed, 4) can be clonally
expanded, and 5) can easily be engineered to express exogenous proteins.
UCMS cells have genetic and surface markers of mesenchymal stem
cells (positive for CD10, CD13, CD29, CD44, and CD90 and negative
for CD14, CD33, CD56, CD31, CD34, CD45, and HLA-DR) and appear to
be stable in terms of their surface marker expression in early passage
(passages 4-8). Unlike traditional mesenchymal stem cells derived
from adult bone marrow stromal cells, small populations of UCMS
cells express endoglin (SH2, CD105) and CD49e at passage 8. UCMS
cells express growth factors and angiogenic factors, suggesting
that they may be used to treat neurodegenerative disease. To test
the therapeutic value of UCMS cells, undifferentiated human UCMS
cells were transplanted into the brains of hemiparkinsonian rats
that were not immune-suppressed. UCMS cells ameliorated apomorphine-induced
rotations in the pilot test. UCMS cells transplanted into normal
rats did not produce brain tumors, rotational behavior, or a frank
host immune rejection response. In summary, the umbilical cord matrix
appears to be a rich, noncontroversial, and inexhaustible source
of primitive mesenchymal stem cells.
Olfactory mucosa autografts in human spinal cord injury:
a pilot clinical study.
Lima C, et al.
J Spinal Cord Med. 2006;29(3):191-203; discussion 204-6.
BACKGROUND/OBJECTIVE: Olfactory mucosa is a readily accessible source
of olfactory ensheathing and stem-like progenitor cells for neural
repair. To determine the safety and feasibility of transplanting
olfactory mucosa autografts into patients with traumatically injured
spinal cords, a human pilot clinical study was conducted.
METHODS: Seven patients ranging from 18 to 32 years of age (American
Spinal Injury Association [ASIA] class A) were treated at 6 months
to 6.5 years after injury. Olfactory mucosa autografts were transplanted
into lesions ranging from 1 to 6 cm that were present at C4-T6 neurological
levels. Operations were performed from July 2001 through March 2003.
Magnetic resonance imaging (MRI), electromyography (EMG), and ASIA
neurological and otolaryngological evaluations were performed before
and after surgery.
RESULTS: MRI studies revealed moderate to complete filling of the
lesion sites. Two patients reported return of sensation in their
bladders, and one of these patients regained voluntary contraction
of anal sphincter. Two of the 7 ASIA A patients became ASIA C. Every
patient had improvement in ASIA motor scores. The mean increase
for the 3 subjects with tetraplegia in the upper extremities was
6.3 +/- 1.2 (SEM), and the mean increase for the 4 subjects with
paraplegia in the lower extremities was 3.9 +/- 1.0. Among the patients
who improved in their ASIA sensory neurological scores (all except
one patient), the mean increase was 20.3 +/- 5.0 for light touch
and 19.7 +/- 4.6 for pinprick. Most of the recovered sensation below
the initial level of injury was impaired. Adverse events included
sensory decrease in one patient that was most likely caused by difficulty
in locating the lesion, and there were a few instances of transient
pain that was relieved by medication. EMG revealed motor unit potential
when the patient was asked to perform movement.
CONCLUSION: This study shows that olfactory mucosa autograft transplantation
into the human injured spinal cord is feasible, relatively safe,
and potentially beneficial. The procedure involves risks generally
associated with any surgical procedure. Long-term patient monitoring
is necessary to rule out any delayed side effects and assess any
Induction of neuronal differentiation of adult human
olfactory neuroepithelial-derived progenitors.
Zhang X, et al.
Brain Res. 2006 Feb 16;1073-1074:109-19. Epub 2006 Feb 7.
Abstract: Neurosphere forming cells (NSFCs) have been established
from cultures of adult olfactory neuroepithelium obtained from patients
and cadavers as described previously. They remained undifferentiated
in serum or defined media with or without neurotrophic factors.
Many factors affect the differentiation of stem cells along a neuronal
pathway. Retinoic acid (RA), forskolin (FN), and sonic hedgehog
(Shh) have been reported to act as growth promoters during neurogenesis
of embryonic CNS in vivo. The effect of RA, FN, and Shh on NSFCs'
neuronal lineage restriction has not been described. The application
of RA, FN, and Shh to NSFCs induced the expression of motoneuronal
transcription factors, tyrosine hydroxylase, an indicator of dopamine
production, and neurite formation. These studies further heighten
the potential for using olfactory neuroepithelial progenitors for
future autologous cell replacement strategies in neurodegenerative
conditions and trauma as well as for use in diagnostic evaluation.
Role of transcription factors in motoneuron differentiation
of adult human olfactory neuroepithelial-derived progenitors.
Zhang X, et al.
Stem Cells. 2006 Feb;24(2):434-42. Epub 2005 Sep 1.
Abstract: Neurosphereforming cell (NSFC) lines have been established
from cultures of human adult olfactory neuroepithelium. Few of these
cells ever express mature neuronal or glial markers in minimal essential
medium supplemented with 10% fetal bovine serum or defined medium.
However, these neural progenitors have the potential to differentiate
along glial or neuronal lineages. To evaluate the potential of NSFCs
to form motoneurons, transcription factors Olig2, Ngn2, and HB9
were introduced into NSFCs to determine if their expression is sufficient
for motoneuron specification and differentiation, as has been shown
in the early development of the avian and murine central nervous
systems in vivo. NSFCs transfected with Olig2, Ngn2, and HB9 alone
exhibited no phenotypic lineage restriction. In contrast, simultaneous
transfection of Ngn2 and HB9 cDNA increased the expression of Isl1/2,
a motoneuron marker, when the cells were maintained in medium supplemented
with retinoic acid, forskolin, and sonic hedgehog. Furthermore,
a population of Olig2-expressing NSFCs also expressed Ngn2. Cotransfection
of NSFCs with Olig2 and HB9, but not Olig2 and Ngn2, increased Isl1/2
expression. Coculture of NSFCs trans-fected with Ngn2-HB92 or Olig2
and HB9 with purified chicken skeletal muscle demonstrated frequent
contacts that resembled neuromuscular junctions. These studies demonstrate
that transcription factors governing the early development of chick
and mouse motoneuron formation are able to drive human adult olfactory
neuroepithelial progenitors to differentiate into motoneurons in
vitro. Our long-term goal is to develop cell populations for future
studies of the therapeutic utility of these olfactory-derived NSFCs
for autologous cell replacement strategies for central nervous system
trauma and neurodegenerative diseases.
Bone marrow production of lung cells: the impact of
G-CSF, cardiotoxin, graded doses of irradiation, and subpopulation
Aliotta JM, et al.
Exp Hematol. 2006 Feb;34(2):230-41.
OBJECTIVE: Previous studies have demonstrated the production of
various types of lung cells from marrow cells under diverse experimental
conditions. Our aim was to identify some of the variables that influence
conversion in the lung.
METHODS: In separate experiments, mice received various doses of
total-body irradiation followed by transplantation with whole bone
marrow or various subpopulations of marrow cells (Lin(-/+), c-kit(-/+),
Sca-1(-/+)) from GFP(+) (C57BL/6-TgN[ACTbEGFP]1Osb) mice. Some were
given intramuscular cardiotoxin and/or mobilized with granulocyte
colony-stimulating factor (G-CSF).
RESULTS: The production of pulmonary epithelial cells from engrafted
bone marrow was established utilizing green fluorescent protein
(GFP) antibody labeling to rule out autofluorescence and deconvolution
microscopy to establish the colocaliztion of GFP and cytokeratin
and the absence of CD45 in lung samples after transplantation. More
donor-derived lung cells (GFP(+)/CD45(-)) were seen with increasing
doses of radiation (5.43% of all lung cells, 1200 cGy). In the 900-cGy
group, 61.43% of GFP(+)/CD45(-) cells were also cytokeratin(+).
Mobilization further increased GFP(+)/CD45(-) cells to 7.88% in
radiation-injured mice. Up to 1.67% of lung cells were GFP(+)/CD45(-)
in radiation-injured mice transplanted with Lin(-), c-kit(+), or
Sca-1(+) marrow cells. Lin(+), c-kit(-), and Sca-1(-) subpopulations
did not significantly engraft the lung.
CONCLUSIONS: We have established that marrow cells are capable of
producing pulmonary epithelial cells and identified radiation dose
and G-CSF mobilization as variables influencing the production of
lung cells from marrow cells. Furthermore, the putative lung cell-producing
marrow cell has the phenotype of a hematopoietic stem cell.
Results of the cord blood transplantation study (COBLT):
outcomes of unrelated donor umbilical cord blood transplantation
in pediatric patients with lysosomal and peroxisomal storage diseases.
Martin PL, et al.
Biol Blood Marrow Transplant. 2006 Feb;12(2):184-94.
Abstract: The Cord Blood Transplantation Study (COBLT), sponsored
by the National Heart, Lung, and Blood Institute, is a phase II
multicenter study designed to evaluate the use of cord blood in
allogeneic transplantation. In this report, we evaluated the outcomes
of cord blood transplantation in 69 patients with lysosomal and
peroxisomal storage diseases. Patients with mucopolysaccharidoses
I to III, mucolipidoses (ML) II (n = 36), adrenoleukodystrophy (n
= 8), metachromatic leukodystrophy (n = 6), Krabbe disease (n =
16), and Tay-Sachs disease (n = 3) were enrolled between August
1999 and June 2004. All patients received the same preparative regimen,
graft-versus-host disease (GVHD) prophylaxis, and supportive care.
End points included survival, engraftment, GVHD, and toxicity. Sixty-nine
patients (64% men; 81% white) with a median age of 1.8 years underwent
transplantation with a median cell dose of 8.7 x 10(7)/kg. One-year
survival was 72% (95% confidence interval, 61%-83%). The cumulative
incidence of neutrophil engraftment by day 42 was 78% (95% confidence
interval, 67%-87%) at a median of 25 days. Grade II to IV acute
GVHD occurred in 36% of patients. Cord blood donors are readily
available for rapid transplantation. Cord blood transplantation
should be considered as frontline therapy for young patients with
lysosomal and peroxisomal storage diseases.
Nonmyeloablative hematopoietic stem cell transplantation
for systemic lupus erythematosus.
Burt RK, et al.
JAMA. 2006 Feb 1;295(5):527-35.
CONTEXT: Manifestations of systemic lupus erythematosus (SLE) may
in most patients be ameliorated with medications that suppress the
immune system. Nevertheless, there remains a subset of SLE patients
for whom current strategies are insufficient to control disease.
OBJECTIVE: To assess the safety of intense immunosuppression and
autologous hematopoietic stem cell support in patients with severe
and treatment-refractory SLE.
DESIGN, SETTING, AND PARTICIPANTS: A single-arm trial of 50 patients
with SLE refractory to standard immunosuppressive therapies and
either organ- or life-threatening visceral involvement. Patients
were enrolled from April 1997 through January 2005 in an autologous
nonmyeloablative hematopoietic stem cell transplantation (HSCT)
study at a single US medical center.
INTERVENTIONS: Peripheral blood stem cells were mobilized with cyclophosphamide
(2.0 g/m2) and granulocyte colony-stimulating factor (5 microg/kg
per day), enriched ex vivo by CD34+ immunoselection, cryopreserved,
and reinfused after treatment with cyclophosphamide (200 mg/kg)
and equine antithymocyte globulin (90 mg/kg).
MAIN OUTCOME MEASURES: The primary end point was survival, both
overall and disease-free. Secondary end points included SLE Disease
Activity Index (SLEDAI), serology (antinuclear antibody [ANA] and
anti-double-stranded (ds) DNA), complement C3 and C4, and changes
in renal and pulmonary organ function assessed before treatment
and at 6 months, 12 months, and then yearly for 5 years.
RESULTS: Fifty patients were enrolled and underwent stem cell mobilization.
Two patients died after mobilization, one from disseminated mucormycosis
and another from active lupus after postponing the transplantation
for 4 months. Forty-eight patients underwent nonmyeloablative HSCT.
Treatment-related mortality was 2% (1/50). By intention to treat,
treatment-related mortality was 4% (2/50). With a mean follow-up
of 29 months (range, 6 months to 7.5 years) for patients undergoing
HSCT, overall 5-year survival was 84%, and probability of disease-free
survival at 5 years following HSCT was 50%. Secondary analysis demonstrated
stabilization of renal function and significant improvement in SLEDAI
score, ANA, anti-ds DNA, complement, and carbon monoxide diffusion
lung capacity adjusted for hemoglobin.
CONCLUSIONS: In treatment-refractory SLE, autologous nonmyeloablative
HSCT results in amelioration of disease activity, improvement in
serologic markers, and either stabilization or reversal of organ
dysfunction. These data are nonrandomized and thus preliminary,
providing the foundation and justification for a definitive randomized
trial. Clinical Trial Registration ClinicalTrials.gov Identifier:
Autologous bone marrow-derived stem-cell transfer
in patients with ST-segment elevation myocardial infarction: double-blind,
randomised controlled trial.
Janssens S, et al.
Lancet. 2006 Jan 14;367(9505):113-21.
BACKGROUND: The benefit of reperfusion therapies for ST-elevation
acute myocardial infarction (STEMI) is limited by post-infarction
left-ventricular (LV) dysfunction. Our aim was to investigate the
effect of autologous bone marrow-derived stem cell (BMSC) transfer
in the infarct-related artery on LV function and structure.
METHODS: We did a randomised, double-blind, placebo-controlled study
in 67 patients from whom we harvested bone marrow 1 day after successful
percutaneous coronary intervention for STEMI. We assigned patients
optimum medical treatment and infusion of placebo (n=34) or BMSC
(n=33). Our primary endpoint was the increase in LV ejection fraction
and our secondary endpoints were change in infarct size and regional
LV function at 4 months' follow-up, all assessed by MRI. We assessed
changes in myocardial perfusion and oxidative metabolism with serial
1-[11C]acetate PET. Analyses were per protocol. This study is registered
with , number NCT00264316.
FINDINGS: Mean global LV ejection fraction 4 days after percutaneous
coronary intervention was 46.9% (SD 8.2) in controls and 48.5% (7.2)
in BMSC patients, and increased after 4 months to 49.1% (10.7) and
51.8% (8.8; OR for treatment effect 1.036, 95% CI 0.961-1.118, p=0.36).
Compared with placebo infusion, BMSC transfer was associated with
a significant reduction in myocardial infarct size (BMSC treatment
effect 28%, p=0.036) and a better recovery of regional systolic
function. Myocardial perfusion and metabolism increased similarly
in both groups. We noted no complications associated with BMSC transfer
and all but one patient in the BMSC group completed the 4 months'
INTERPRETATION: Intracoronary transfer of autologous bone marrow
cells within 24 h of optimum reperfusion therapy does not augment
recovery of global LV function after myocardial infarction, but
could favourably affect infarct remodelling.
Clonal analysis of adult human olfactory neurosphere
Othman M, et al.
Biotech Histochem. 2005 Sep-Dec;80(5-6):189-200.
Abstract: Olfactory neuroepithelium (ONe) is unique because it contains
progenitor cells capable of mitotic division that replace damaged
or lost neurons throughout life. We isolated populations of ONe
progenitors from adult cadavers and patients undergoing nasal sinus
surgery that were heterogeneous and consisted of neuronal and glial
progenitors. Progenitor lines have been obtained from these cultures
that continue to divide and form nestin positive neurospheres. In
the present study, we used clonal and population analyses to probe
the self-renewal and multipotency of the neurosphere forming cells
(NSFCs). NSFCs plated at the single cell level produced additional
neurospheres; dissociation of these spheres resulted in mitotically
active cells that continued to divide and produce spheres as long
as they were subcultured. The mitotic activity of clonal NSFCs was
assessed using bromodeoxyuridine (BrdU) incorporation. Lineage restriction
of the clonal cultures was determined using a variety of antibodies
that were characteristic of different levels of neuronal commitment:
ss-tubulin isotype III, neural cell adhesion molecule (NCAM) and
microtubule associated protein (MAP2), or glial restriction: astrocytes,
glial fibrillary acidic protein (GFAP); and oligodendrocytes, galactocerebroside
(GalC). Furthermore, nestin expression, a marker indicative of progenitor
nature, decreased in defined medium compared to serum-containing
medium. Therefore, adult human ONe-derived neural progenitors retain
their capacity for self-renewal, can be clonally expanded, and offer
multipotent lineage restriction. Therefore, they are a unique source
of progenitors for future cell replacement strategies in the treatment
of neurotrauma and neurodegenerative diseases.
Administered mesenchymal stem cells protect against ischemic acute
renal failure through differentiation-independent mechanisms
Florian Togel, et al.
Am J Physiol Renal Physiol 2005 Jul;289(1):F31-42. Epub 2005 Feb
Abstract: Severe acute renal failure (ARF) remains a common, largely
treatment-resistant clinical problem with disturbingly high mortality
rates. Therefore, we tested whether administration of multipotent
mesenchymal stem cells (MSC) to anesthetized rats with ischemia-reperfusion-induced
ARF (40-min bilateral renal pedicle clamping) could improve the
outcome through amelioration of inflammatory, vascular, and apoptotic/necrotic
manifestations of ischemic kidney injury. Accordingly, intracarotid
administration of MSC (approximately 10(6)/animal) either immediately
or 24 h after renal ischemia resulted in significantly improved
renal function, higher proliferative and lower apoptotic indexes,
as well as lower renal injury and unchanged leukocyte infiltration
scores. Such renoprotection was not obtained with syngeneic fibroblasts.
Using in vivo two-photon laser confocal microscopy, fluorescence-labeled
MSC were detected early after injection in glomeruli, and low numbers
attached at microvasculature sites. However, within 3 days of administration,
none of the administered MSC had differentiated into a tubular or
endothelial cell phenotype. At 24 h after injury, expression of
proinflammatory cytokines IL-1beta, TNF-alpha, IFN-gamma, and inducible
nitric oxide synthase was significantly reduced and that of anti-inflammatory
IL-10 and bFGF, TGF-alpha, and Bcl-2 was highly upregulated in treated
kidneys. We conclude that the early, highly significant renoprotection
obtained with MSC is of considerable therapeutic promise for the
cell-based management of clinical ARF. The beneficial effects of
MSC are primarily mediated via complex paracrine actions and not
by their differentiation into target cells, which, as such, appears
to be a more protracted response that may become important in late-stage
Human adult olfactory neural progenitors rescue axotomized
rodent rubrospinal neurons and promote functional recovery.
Xiao M, et al.
Exp Neurol. 2005 Jul;194(1):12-30.
Abstract: Previously, our lab reported the isolation of patient-specific
neurosphere-forming progenitor lines from human adult olfactory
epithelium from cadavers as well as patients undergoing nasal sinus
surgery. RT-PCR and ELISA demonstrated that the neurosphere-forming
cells (NSFCs) produced BDNF. Since rubrospinal tract (RST) neurons
have been shown to respond to exogenous BNDF, it was hypothesized
that if the NSFCs remained viable following engraftment into traumatized
spinal cord, they would rescue axotomized RS neurons from retrograde
cell atrophy and promote functional recovery. One week after a partial
cervical hemisection, GFP-labeled NSFCs suspended in Matrigel matrix
or Matrigel matrix alone was injected into the lesion site. GFP-labeled
cells survived up to 12 weeks in the lesion cavity or migrated within
the ipsilateral white matter; the apparent number and mean somal
area of fluorogold (FG)-labeled axotomized RST neurons were greater
in the NSFC-engrafted rats than in lesion controls. Twelve weeks
after engraftment, retrograde tracing with FG revealed that some
RST neurons regenerated axons 4-5 segments caudal to the engraftment
site; anterograde tracing with biotinylated dextran amine confirmed
regeneration of RST axons through the transplants within the white
matter for 3-6 segments caudal to the grafts. A few RST axons terminated
in gray matter close to motoneurons. Matrix alone did not elicit
regeneration. Behavioral analysis revealed that NSFC-engrafted rats
displayed better performance during spontaneous vertical exploration
and horizontal rope walking than lesion Matrigel only controls 11
weeks post transplantation. These results emphasize the unique potential
of human olfactory neuroepithelial-derived progenitors as an autologous
source of stem cells for spinal cord repair.
Generation of islet-like hormone-producing cells in
vitro from adult human pancreas.
Atouf F, et al.
Cell Transplant. 2005;14(10):735-48.
Abstract: Transplantation of pancreatic islets can provide long-lasting
insulin independence for diabetic patients, but the current islet
supply is limited. Here we describe a new in vitro system that utilizes
adult human pancreatic islet-enriched fractions to generate hormone-producing
cells over 3-4 weeks of culture. By labeling proliferating cells
with a retrovirus-expressing green fluorescent protein, we show
that in this system hormone-producing cells are generated de novo.
These hormone-producing cells aggregate to form islet-like cell
clusters. The cell clusters, when tested in vitro, release insulin
in response to glucose and other secretagogues. After transplantation
into immunodeficient, nondiabetic mice, the islet-like cell clusters
survive and release human insulin. We propose that this system will
be useful as an experimental tool for investigating mechanisms for
generating new islet cells from the postnatal pancreas, and for
designing strategies to generate physiologically competent pancreatic
islet cells ex vivo.
Human bone marrow-derived mesenchymal stem cells in
the treatment of gliomas.
Nakamizo A, et al.
Cancer Res. 2005 Apr 15;65(8):3307-18.
Abstract: The poor survival of patients with human malignant gliomas
relates partly to the inability to deliver therapeutic agents to
the tumor. Because it has been suggested that circulating bone marrow-derived
stem cells can be recruited into solid organs in response to tissue
stresses, we hypothesized that human bone marrow-derived mesenchymal
stem cells (hMSC) may have a tropism for brain tumors and thus could
be used as delivery vehicles for glioma therapy. To test this, we
isolated hMSCs from bone marrow of normal volunteers, fluorescently
labeled the cells, and injected them into the carotid artery of
mice bearing human glioma intracranial xenografts (U87, U251, and
LN229). hMSCs were seen exclusively within the brain tumors regardless
of whether the cells were injected into the ipsilateral or contralateral
carotid artery. In contrast, intracarotid injections of fibroblasts
or U87 glioma cells resulted in widespread distribution of delivered
cells without tumor specificity. To assess the potential of hMSCs
to track human gliomas, we injected hMSCs directly into the cerebral
hemisphere opposite an established human glioma and showed that
the hMSCs were capable of migrating into the xenograft in vivo.
Likewise, in vitro Matrigel invasion assays showed that conditioned
medium from gliomas, but not from fibroblasts or astrocytes, supported
the migration of hMSCs and that platelet-derived growth factor,
epidermal growth factor, or stromal cell-derived factor-1alpha,
but not basic fibroblast growth factor or vascular endothelial growth
factor, enhanced hMSC migration. To test the potential of hMSCs
to deliver a therapeutic agent, hMSCs were engineered to release
IFN-beta (hMSC-IFN-beta). In vitro coculture and Transwell experiments
showed the efficacy of hMSC-IFN-beta against human gliomas. In vivo
experiments showed that treatment of human U87 intracranial glioma
xenografts with hMSC-IFN-beta significantly increase animal survival
compared with controls (P < 0.05). We conclude that hMSCs can
integrate into human gliomas after intravascular or local delivery,
that this engraftment may be mediated by growth factors, and that
this tropism of hMSCs for human gliomas can be exploited to therapeutic
Preservation from left ventricular remodeling by front-integrated
revascularization and stem cell liberation in evolving acute myocardial
infarction by use of granulocyte-colony-stimulating factor (FIRSTLINE-AMI).
Ince H, et al.
Circulation. 2005 Nov 15;112(20):3097-106. Epub 2005 Nov 7.
BACKGROUND: Considering experimental evidence that stem cells enhance
myocardial regeneration and granulocyte colony-stimulating factor
(G-CSF) mediates mobilization of CD34+ mononuclear blood stem cells
(MNCCD34+), we tested the impact of G-CSF integrated into primary
percutaneous coronary intervention (PCI) management of acute myocardial
infarction in man.
METHODS AND RESULTS: Fifty consecutive patients with ST-segment
elevation myocardial infarction were subjected to primary PCI stenting
with abciximab and followed up for 6 months; 89+/-35 minutes after
successful PCI, 25 patients were randomly assigned in this pilot
study (PROBE design) to receive subcutaneous G-CSF at 10 microg/kg
body weight for 6 days in addition to standard care, including aspirin,
clopidogrel, an ACE inhibitor, beta-blocking agents, and statins.
By use of CellQuest software on peripheral blood samples incubated
with CD45 and CD34, mobilized MNCCD34+ were quantified on a daily
basis. With homogeneous demographics and clinical and infarct-related
characteristics, G-CSF stimulation led to mobilization of MNCCD34+
to between 3.17+/-2.93 MNCCD34+/microL at baseline and 64.55+/-37.11
MNCCD34+/microL on day 6 (P<0.001 versus control); there was
no indication of leukocytoclastic effects, significant pain, impaired
rheology, inflammatory reactions, or accelerated restenosis at 6
months. Within 35 days, G-CSF and MNCCD34+ liberation led to enhanced
resting wall thickening in the infarct zone of between 0.29+/-0.22
and 0.99+/-0.32 mm versus 0.49+/-0.29 mm in control subjects (P<0.001);
under inotropic challenge with dobutamine (10 microg.kg(-1).min(-1)),
wall motion score index showed improvement from 1.66+/-0.23 to 1.41+/-0.21
(P<0.004 versus control) and to 1.35+/-0.24 after 4 months (P<0.001
versus control), respectively, coupled with sustained recovery of
wall thickening to 1.24+/-0.31 mm (P<0.001 versus control) at
4 months. Accordingly, resting wall motion score index improved
with G-CSF to 1.41+/-0.25 (P<0.001 versus control), left ventricular
end-diastolic diameter to 55+/-5 mm (P<0.002 versus control),
and ejection fraction to 54+/-8% (P<0.001 versus control) after
4 months. Morphological and functional improvement with G-CSF was
corroborated by enhanced metabolic activity and 18F-deoxyglucose
uptake in the infarct zone (P<0.001 versus control).
CONCLUSIONS: G-CSF and mobilization of MNC(CD34+) after reperfusion
of infarcted myocardium may offer a pragmatic strategy for preservation
of myocardium and prevention of remodeling without evidence of aggravated
Improvement of bilateral motor functions in patients
with Parkinson disease through the unilateral intraputaminal infusion
of glial cell line-derived neurotrophic factor.
Slevin JT, et al.
J Neurosurg. 2005 Feb;102(2):216-22.
OBJECT: Glial cell line-derived neurotrophic factor (GDNF) has demonstrated
significant antiparkinsonian actions in several animal models and
in a recent pilot study in England in which four of five patients
received bilateral putaminal delivery. In the present study the
authors report on a 6-month unilateral intraputaminal GDNF infusion
in 10 patients with advanced Parkinson disease (PD).
METHODS: Patients with PD in a functionally defined on and off state
were evaluated 1 week before and 1 and 4 weeks after intraputaminal
catheter implantation in the side contralateral to the most affected
side. Each patient was placed on a dose-escalation regimen of GDNF:
3, 10, and 30 microg/day at successive 8-week intervals, followed
by a 1-month wash-out period. The Unified Parkinson's Disease Rating
Scale (UPDRS) total scores in the on and off states significantly
improved 34 and 33%, respectively, at 24 weeks compared with baseline
scores (95% confidence interval [CI] 18-47% for off scores and 16-51%
for on scores). In addition, UPDRS motor scores in both the on and
off states significantly improved by 30% at 24 weeks compared with
baseline scores (95% CI 15-48% for off scores and 5-61% for on scores).
Improvements occurred bilaterally, as measured by balance and gait
and increased speed of hand movements. All significant improvements
of motor function continued through the wash-out period. The only
observed side effects were transient Lhermitte symptoms in two patients.
CONCLUSIONS: Analysis of the data in this open-label study demonstrates
the safety and potential efficacy of unilateral intraputaminal GDNF
infusion. Unilateral administration of the protein resulted in significant,
sustained bilateral effects.
Regeneration of human infarcted heart muscle by intracoronary
autologous bone marrow cell transplantation in chronic coronary
artery disease: the IACT Study.
Strauer BE, et al.
J Am Coll Cardiol. 2005 Nov 1;46(9):1651-8.
OBJECTIVES: Stem cell therapy may be useful in chronic myocardial
infarction (MI); this is conceivable, but not yet demonstrated in
BACKGROUND: After acute MI, bone marrow-derived cells improve cardiac
METHODS: We treated 18 consecutive patients with chronic MI (5 months
to 8.5 years old) by the intracoronary transplantation of autologous
bone marrow mononuclear cells and compared them with a representative
control group without cell therapy.
RESULTS: After three months, in the transplantation group, infarct
size was reduced by 30% and global left ventricular ejection fraction
(+15%) and infarction wall movement velocity (+57%) increased significantly,
whereas in the control group no significant changes were observed
in infarct size, left ventricular ejection fraction, or wall movement
velocity of infarcted area. Percutaneous transluminal coronary angioplasty
alone had no effect on left ventricular function. After bone marrow
cell transplantation, there was an improvement of maximum oxygen
uptake (VO2max, +11%) and of regional 18F-fluor-desoxy-glucose uptake
into infarct tissue (+15%).
CONCLUSIONS: These results demonstrate that functional and metabolic
regeneration of infarcted and chronically avital tissue can be realized
in humans by bone marrow mononuclear cell transplantation.
Surgical ventricular remodeling for patients with
clinically advanced congestive heart failure and severe left ventricular
Patel ND, et al.
J Heart Lung Transplant. 2005 Dec;24(12):2202-10. Epub 2005 Sep
BACKGROUND: Surgical ventricular remodeling (SVR) is an accepted
therapy for post-infarction ventricular remodeling. Current literature
on SVR outcomes has focused on heterogeneous populations with regard
to left ventricular function and New York Heart Association (NYHA)
class. We assessed outcomes after SVR in patients with advanced
congestive heart failure (CHF) (NYHA Class III/IV) and a pre-operative
ejection fraction (EF) < or =20%.
METHODS: Data were analyzed for 51 consecutive SVR patients from
January 2002 to June 2004. Cardiac catheterization, echocardiography
and magnetic resonance imaging (MRI) identified 62.7% (32 of 51)
of patients with an EF < or =20%, with the majority having an
EF < or =15% (65.6%; 21 of 32). Cox regression analysis was performed
to determine predictors of mortality in patients with an EF <
or =20%. Follow-up was 100% (32 of 32) complete.
RESULTS: Mean age was 61.9 +/- 10.3 (range 40 to 80) years with
a male:female ratio of 27:5. Operative mortality was 6.3% (2 of
32). Twenty-two percent (7 of 32) had concomitant mitral valve procedures.
Follow-up demonstrated a statistically significant improvement in
left ventricular volumes and EF in survivors. Cox regression analysis
identified the following to be significant predictors of mortality:
pre-operative left ventricular end-systolic volume index >130
ml/m2; pre-operative diabetes; and intra-aortic balloon pump usage.
Pre-operatively, all patients (32 of 32) were categorized as NYHA
Class III/IV, with 69% (22 of 32) improving to NYHA Class I/II at
follow-up (p < 0.01). Survival did not differ statistically between
patients with an EF < or =20% and an EF >20% (n = 19).
CONCLUSIONS: Our results indicate that SVR improves left ventricular
function and functional status for patients with advanced CHF and
a pre-operative EF < or =20%. Therefore, SVR is a viable surgical
alternative for patients with severe left ventricular dysfunction.
Transplantation of umbilical-cord blood in babies
with infantile Krabbe's disease.
Escolar ML, et al.
N Engl J Med. 2005 May 19;352(20):2069-81.
BACKGROUND: Infantile Krabbe's disease produces progressive neurologic
deterioration and death in early childhood. We hypothesized that
transplantation of umbilical-cord blood from unrelated donors before
the development of symptoms would favorably alter the natural history
of the disease among newborns in whom the disease was diagnosed
because of a family history. We compared the outcomes among these
newborns with the outcomes among infants who underwent transplantation
after the development of symptoms and with the outcomes in an untreated
cohort of affected children.
METHODS: Eleven asymptomatic newborns (age range, 12 to 44 days)
and 14 symptomatic infants (age range, 142 to 352 days) with infantile
Krabbe's disease underwent transplantation of umbilical-cord blood
from unrelated donors after myeloablative chemotherapy. Engraftment,
survival, and neurodevelopmental function were evaluated longitudinally
for four months to six years.
RESULTS: The rates of donor-cell engraftment and survival were 100
percent and 100 percent, respectively, among the asymptomatic newborns
(median follow-up, 3.0 years) and 100 percent and 43 percent, respectively,
among the symptomatic infants (median follow-up, 3.4 years). Surviving
patients showed durable engraftment of donor-derived hematopoietic
cells with restoration of normal blood galactocerebrosidase levels.
Infants who underwent transplantation before the development of
symptoms showed progressive central myelination and continued gains
in developmental skills, and most had age-appropriate cognitive
function and receptive language skills, but a few had mild-to-moderate
delays in expressive language and mild-to-severe delays in gross
motor function. Children who underwent transplantation after the
onset of symptoms had minimal neurologic improvement.
CONCLUSIONS: Transplantation of umbilical-cord blood from unrelated
donors in newborns with infantile Krabbe's disease favorably altered
the natural history of the disease. Transplantation in babies after
symptoms had developed did not result in substantive neurologic
improvement. Copyright 2005 Massachusetts Medical Society.
Cell-replacement therapy for diabetes: Generating
functional insulin-producing tissue from adult human liver cells.
Sapir T, et al.
Proc Natl Acad Sci U S A. 2005 May 31;102(22):7964-9. Epub 2005
Abstract: Shortage in tissue availability from cadaver donors and
the need for life-long immunosuppression severely restrict the large-scale
application of cell-replacement therapy for diabetic patients. This
study suggests the potential use of adult human liver as alternate
tissue for autologous beta-cell-replacement therapy. By using pancreatic
and duodenal homeobox gene 1 (PDX-1) and soluble factors, we induced
a comprehensive developmental shift of adult human liver cells into
functional insulin-producing cells. PDX-1-treated human liver cells
express insulin, store it in defined granules, and secrete the hormone
in a glucose-regulated manner. When transplanted under the renal
capsule of diabetic, immunodeficient mice, the cells ameliorated
hyperglycemia for prolonged periods of time. Inducing developmental
redirection of adult liver offers the potential of a cell-replacement
therapy for diabetics by allowing the patient to be the donor of
his own insulin-producing tissue.