| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
a Center for Gene Therapy, Tulane University of the Health Sciences, New Orleans, Louisiana, USA;
b Neuronyx Inc., Malvern, Pennsylvania, USA
Key Words. Mesenchymal stem cells • MicroSAGE
Correspondence:
Donald G. Phinney, Ph.D., Center for Gene Therapy and Department of Microbiology and Immunology, SL-99, Room 672 JBJ, Tulane University of the Health Sciences, 1430 Tulane Avenue, New Orleans, Louisiana 70112, USA. Telephone: 504-988-7725; Fax: 504-988-7710; e-mail: dphinne{at}tulane.edu
 |
ABSTRACT |
|---|
 Top Abstract IntroductionMaterials and MethodsResultsDiscussionSummaryReferences |
|---|
|
INTRODUCTION |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionSummaryReferences |
|---|
Similar to hematopoietic stem cells, MSCs subsist in bone marrow in a mitotically quiescent state [9] and possess the capacity for self-renewal [10, 11]. MSCs also adopt glial cell fates in vivo [12] and hence can produce tissue elements that originate from a different embryonic layer, a property recently ascribed to neural stem cells [13]. Despite these remarkable properties, efforts aimed at defining phenotypic characteristics of MSCs have been confounded by the fact that the cells display a variety of morphologies [2, 14] and express various cell lineage-specific antigens that can vary between different preparations and as a function of time in culture, leading to differing conclusions about the biological nature of the cells. For example, several early studies showed that marrow stromal cells, one vernacularism for MSCs, expressed vimentin and smooth muscle actin [15], but under certain conditions also expressed desmin [16], indicating that the cells were most similar to vascular smooth muscle cells or marrow myoid cells, respectively. Alternatively, histological studies showed that marrow stromal cells surround the endothelium of venous sinuses indicating that they are analogous to vascular pericytes [17]. The analogy is noteworthy because pericytes are also oligopotential mesenchymal progenitors [18]. In other studies CFU-F, another MSC vernacularism, was reported to express factor VIII [19], laminin and type IV collagen [20] indicating that the cells are endothelial-like in origin. Finally, stromal stem cells, a third MSC synonym, were shown to colonize the embryonic liver, spleen, and bone marrow but not the yolk sac prior to establishment of hematopoiesis, suggesting that they are derived in the yolk sac from the hemangioblast [21].
More recent efforts to characterize MSCs have relied on analyzing the expression profiles of different gene families or classes of biological molecules. For example, human MSCs cultured under conditions that inhibit differentiation were shown to express numerous cytokines, including interleukin 6 (IL-6), IL-11, G-CSF, macrophage colony-stimulating factor (M-CSF), stem cell factor, and leukemia inhibitory factor [22]. Similar experiments have analyzed the complement of expressed receptor tyrosine kinases [14] and insulin-like growth factor-binding proteins [23] in clonal and nonclonal populations of MSCs. Most recently, the expression profile of approximately 50 genes, including cytokine and mitogen receptors, matrix molecules, and integrins have been described on a homogenous preparation of human MSCs [7]. Although significant, these studies collectively do not provide an accurate molecular description of MSCs as the authors employed different preparations of cells cultured under different conditions. In no case has a broad sampling of expressed genes been simultaneously analyzed from a defined population of MSCs.
Serial analysis of gene expression (SAGE) provides a means to analyze the entire complement of expressed transcripts in a cell [24]. SAGE has been used to study genes involved in malignancy [25] and molecularly define the differentiation of blood monocytes into macrophages and dendritic cells [26, 27]. To better define the molecular phenotype of MSCs, we used a modified protocol for microSAGE [28] to rapidly catalog 2,353 mRNAs expressed by a single cell-derived colony of undifferentiated human MSCs. Our analysis demonstrates that a clonal population of human MSCs is molecularly heterogeneous, simultaneously expressing transcripts characteristic of various mesenchymal cell lineages. Other expressed transcripts, including epithelial, endothelial and neuronal lineage-specific mRNAs, neurotrophic factors, and products involved in wound healing, reveal new insight into the biology, ontogeny, and in vivo functions of MSCs.
|
MATERIALS AND METHODS |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionSummaryReferences |
|---|
-minimal essential medium supplemented with 100 µg/ml penicillin, 100 µg/ml streptomycin, 2 mM L-glutamine, and 20% fetal calf serum (Atlanta Biological; Norcross, GA; http://www.atlantabio.com/default.htm) lot selected for rapid growth of the cells. After 24 hours the nonadherent cells were removed and the adherent layer cultured until it reached 50%-70% confluence. Cells were then harvested by incubation with 0.2% trypsin-EDTA and their colony-forming efficiency determined by plating the cells at 10 cells/cm2 in 100 mm dishes (Falcon), culturing for 10 to 14 days, and then counting the number of visible colonies after staining the dishes with Geimsa. Colony-forming efficiency, which is calculated as the percentage of the number of cells initially plated that give rise to visible colonies, was previously shown to predict the life span and differentiation potential of the cells [29]. We screened various human donor populations to identify those with the highest colony-forming efficiency and used one such donor population to isolate single cell-derived colonies generated as described above and isolated using cloning cylinders and trypsin-EDTA.
MicroSAGE Procedure
Total RNA was prepared from a single cell-derived colony of human MSCs using the RNA Isolation Kit (Fluka; Milwaukee, WI; http://www.fluka.com/fluka), enriched for polyadenylated mRNA, converted into double-stranded cDNA, then reduced to 11 bp tags as previously described [28] with the following exceptions. First, all washes were done with 200 µl of buffer, and first-strand cDNA synthesis was carried out using murine moloney leukemia virus reverse transcriptase (RT) (GIBCO BRL; Gaithersburg, MD; http://www.tmc.tulane.edu/sif/tulgib.htm). Second, DNA linkers were ligated to the cDNA in a 50 µl reaction consisting of 1 µl (25 ng) linker A1/B1 and 1 µl (25 ng) linker A2/B2 and ligation was performed using T4 DNA ligase (New England Biolabs; Beverly, MA; http://www.neb.com). The sequence of each oligonucleotide used to prepare the linkers was as follows; A1, 5'-TTCCCTTGGCTTCAGACCCTCAGACTAGGCTTAATAGGGA CATG-3'; B1, 5-TCCCTATTAAGCCTAGTCTGAGGGTCTGAAGCCAAGGG-3'; A2, 5'-TTTGCTCCAGTGCCTACCATCTACAACGATGTACGGGGACATG-3'; B2, 5'-TCCCCGTACATCGTTGTAGATGGTAGGCACTGGAGC-3'. Third, DNA precipitations were done in the presence of 10 mM MgCl2. Fourth, released cDNA fragments were blunt-ended using T4 DNA polymerase (New England Biolabs). Fifth, to generate ditags, 1 µl of the diluted ligation reaction (1:50) was used as input in a 50 µl reaction containing 0.2 mM dNTPs, 525 ng of each primer and 1.5 units of thermostable DNA polymerase (Amplitaq Gold; Applied Biosystems; Foster City, CA; http://home.appliedbiosystems.com) in polymerase chain reaction (PCR) Buffer I (Applied Biosystems) that was amplified for 32 cycles of 30 sec at 95°C, 40 sec at 60°C and 40 sec at 72°C with an initial heat activation of the enzyme for 10 min at 95°C and a final extension of 5 min at 72°C. Primers used for PCR amplification of ditags were as follows: SGAb, 5'-CCCTTGGCTTCAGACCCTCAG-3'; SGBb, 5'-GCTCCAGTGCCGCCTACCATCTAC-3'. Ditags produced from 96 PCR reactions were isolated, cleaved with Nla III, and cloned into pZero (Invitrogen; Carlsbad, CA; http://www.invitrogen.com).
Sequencing and Analysis of Clones
Bacterial colonies were screened by blue/white selection to identify those that harbored vectors containing ditags. Plasmid DNA was then isolated using the QIAprep8 mini-prep kit (Qiagen; Valencia, CA; http://www.qiagen.com), sequenced using the BigDye Terminator Cycle Sequencing Reaction kit (Applied Biosystems) and analyzed using a 377 ABI automated sequencer (Applied Biosystems). Sequence files were analyzed using the SAGE program group [21].
cDNA Library Construction
Total RNA was isolated as described above from a pool of approximately 35 single cell-derived colonies elaborated from the same donor population of human MSCs as used for microSAGE. The cDNA library was constructed using the SMART® cDNA Library Construction Kit (GIBCO BRL). The resulting unamplified library contained approximately 1.6 x 106 independent clones. Following amplification, the library was aliquoted into pools of decreasing complexity to facilitate screening by PCR. Integrity of the cDNA library was measured using human control RT-PCR primers for genes of varying abundance (GIBCO BRL). To validate microSAGE tags, 50 µl of the primary pool of the amplified phage library was boiled for 5 minutes and then aliquots (1 µl) were used as input in PCR reactions (100 µl) containing 100 pmoles of forward and reverse gene-specific primers, 1x PCR buffer (Sigma; St. Louis, MO; http://www.sigma-aldrich.com), 0.2 mM dNTPs (Sigma), and 0.5 U Taq polymerase (Sigma). After an initial denaturation step at 94°C for 3 minutes, reactions were amplified for 30 cycles at 94°C for 30 seconds, 55°-65°C for 45 seconds, and 72°C for 90 seconds, followed by a final incubation at 72°C for 5 minutes. PCR products were electrophoresed through a 1% agarose gel, excised from the gel and purified using GeneElute columns (Sigma), and then cloned using the AdvanTAge PCR cloning kit (Clontech; Palo Alto, CA; http://www.clontech.com). Plasmid DNA was isolated and sequenced as described above to confirm the identity of each product.
Fluorescence-Activated Cell Sorter (FACS) Analysis
Single cell-derived colonies of human MSCs were pooled, washed in phosphate-buffered saline, and counted using a hemocytometer. Aliquots of approximately 2 x 105 cells were pelleted by centrifugation at 500 g for 5 minutes and resuspended in 100 µl of the appropriate antibody for flow cytometry. Monoclonal antibodies (PharMingen; http://www.pharmingen.com) were used for cell surface labeling at a concentration of 5 µg/100 µl in Antibody Diluent (Dako; Carpinteria, CA). Analysis of CD121a expression was done by indirect immunofluorescence using a rat antihuman antibody (PharMingen) and cytokeratin expression measured using a fluorescein isothiocyanate-conjugated pan cytokeratin antibody (Sigma). Isotype controls (PharMingen) for each antibody were run in parallel at the same concentration used for each antibody. Cell labeling was evaluated by FACS analysis (Becton Dickinson; San José, CA; http://www.bd.com).
|
RESULTS |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionSummaryReferences |
|---|
). Second, a 20-fold lower molar concentration of linkers for ligation to the double-stranded cDNA was used, which significantly reduced the amount of linker molecules carried through the remaining procedure. The linker molecules reduce the yield of ditags in the PCR by competing for the primers. Linkers also reduce the cloning efficiency of the ditags by ligating to and terminating the concatenation of the molecules. Finally, ditag ends were blunted with T4 DNA polymerase to prevent the addition of extra non-templated nucleotides during nick translation [30], which can also poison the cloning reaction. These modifications allowed us to rapidly generate 17,767 tags using material pooled from only 96 PCR reactions amplified a total of 32 cycles, an improvement in yield compared to previous published protocols (Fig. 1, Table 1).
|
|
shows the 50 most abundant genes expressed by an MSC colony, some of which are represented by more than one tag. The most abundant transcript detected, which accounts for 3.5% of all tags, represents a novel sequence. Overall, a total of 10 (20%) of the top 50 genes are unidentifiable or cannot be assigned specifically to a single gene. In contrast, 17 of the top 50 tags (34%) represent ribosomal proteins and 23 tags (46%) represent known genes. The latter include products characteristic of mesenchymal cells and previously identified in MSCs, such as vimentin and fibronectin [31], collagen type I and III [32], osteoblast-specific factor 2 [33] and collagen type VI [34]. Other abundant transcripts atypical of mesenchymal cells and not previously described in MSCs include two products highly expressed in neurons, the 2C subunit of the N-methyl-D-aspartate glutamate receptor and glia-derived nexin 1 alpha [35], as well as keratin 8, a characteristic member of the large intermediate filament gene family expressed in epithelial cells [36].
|
). Included among these transcripts of cell differentiation are early markers, such as cbfa1 [37] and fibromudullin [38], and late markers, such as meltrin-alpha [39] and sarcoglycan [40]. The colony also expressed products characteristic of hematopoiesis-supporting stroma, including fibulin-1 and fibulin-2 [41], tenascin-C [42], collagen type VI [34], stromal cell-derived factor 1 [43], and pre-B-cell colony-enhancing factor [44]. Collectively, these data indicate that even in the absence of external cues, MSCs cultured in vitro express characteristics of differentiated mesenchymal cell lineages. These results are consistent with previous reports indicating that human MSC populations are both molecularly and functionally heterogeneous [45, 46].
|
). MSCs also expressed transcripts common to neuronal tissues, such as neurofilament H [50], the high affinity nerve growth factor receptor, glial-derived nexin 1 alpha [35] as well as several neurotrophic factors. Additionally, MSCs expressed high levels of actin together with other peptides involved in actin polymerization/depolymerization, suggesting that the cells are highly motile. Although it is undetermined whether these results imply that MSCs migrate to extra-hematopoietic sites via the circulation, the cells also express several products that play a role in wound repair. These include fibrillin-1, a major contributor to dermal elastic fiber construction during wound repair [51]; dermatopontin, a recently discovered extracellular matrix protein associated with the pathogenesis of fibrosis in hypertrophic scar and systemic sclerosis [52]; thymosin ß-4, which exhibits angiogenic properties, accelerates re-epithelialization, and induces migration of keratinocytes [53], and macrophage migration inhibitory factor, a cytokine shown to participate in wound repair [54].
Validation of MicroSAGE Tags
To validate tags we constructed a cDNA library from a pool of CFU-Fs generated from the same marrow donor and cultured under identical conditions. Screening for the presence of ubiquitous transcripts of varying abundance validated the integrity of the cDNA library (Fig. 3). DNA prepared from the phage library was used as input in PCR reactions containing primers corresponding to genes represented by SAGE tags. Excluding ribosomal proteins, we validated many tags (Table 2 and Fig. 2) with the exception of the N-methyl-D-aspartate 2C glutamate receptor (Fig. 4). Multiple attempts using different primer sets spanning the coding region of this receptor failed to identify any transcripts in the cDNA library, but all successfully amplified the correct DNA fragment from human brain RNA. Therefore, this tag apparently is not unique and likely represents a novel transcript. Some tags were also validated by detection of the corresponding expressed protein using immunocytochemistry (data not shown). Finally, a total of 11 cluster designation (CD) antigens are also included in the database. Expression of each CD antigen was validated by flow cytometry using pools of MSC colonies as source material (Fig. 5). All cells in the population expressed only two of the antigens, CD44 and CD59, providing further evidence that the single cell-derived MSC colony is molecularly heterogeneous.
|
|
|
|
DISCUSSION |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionSummaryReferences |
|---|
In addition to mesenchymal lineage-specific transcripts, MSCs also expressed mRNAs common to neural tissues. It is unclear whether expression of these transcripts reflects the entry of MSCs into a developmental program that specifies neural cell fates. Previous studies have shown that MSCs can adopt glial and neuronal cell fates in vivo [12]. Alternatively, mesenchymal cells have previously been reported to express products common to neuronal cells, including neurofilaments and excitatory amino acid receptors [58, 59]. Therefore, expression by MSCs may reflect an important but ill-defined role for these products in connective tissues.
We also detected expression of several neurotrophic factors by the MSC colony, including pigment epithelial-derived factor, glial-derived nexin 1, and macrophage migration inhibitory factor. These products have been shown to promote neuronal cell survival [60, 61] as well as induce neurite outgrowth in cultured neurons [62, 63]. Expression of these products may explain why MSCs transplanted into the central nervous system improve functional recovery of mice following induction of stroke [64]. Previous studies have documented that dense innervation by nerve fibers in bone marrow lies in intimate association with marrow stromal cells [65]. Accordingly, we hypothesize that MSCs normally produce the neurotrophic factors identified by SAGE to promote and maintain nervous innervation into bone and bone marrow [66] and augment the ramification of fibers during periods of growth and reparation due to injury. Interestingly, efferent sympathetic nerve activity has been shown to regulate the mobilization and proliferation of hematopoietic cells [65, 67]. Possibly, similar signals released locally may impinge upon MSCs and control various aspects of their function, including those that affect hematopoiesis.
Another unique characteristic revealed by our microSAGE analysis is the expression by MSCs of mRNAs common to endothelial and epithelial cells. Simultaneous coexpression of cytokeratins, vascular markers, and mesenchymal antigens is also a distinguishing feature of mesothelial cells. Recent studies suggest that aspects of the splanchnic mesothelium undergo an epithelial to mesenchymal transition during embryogenesis, producing a pluripotential mesenchyme that yields HSCs, angioblasts, smooth muscle cells, and fibroblasts [49]. This secondary mesenchyme transiently expresses epithelial, endothelial, and mesenchymal antigens. Therefore, MSCs may be an adult remnant of this embryonic tissue and as such retain a stem cell-like phenotype. A mesothelial origin of MSCs is also supported by the fact that mesothelial tumors typically consist of a mixture of two cell types, spindle-shaped mesenchymal stromal cells and epithelial-like cells [68]. Finally, transient expression of cytokeratins also occurs in blastemal cells of the regenerating newt limb and is thought to maintain the cells in an undifferentiated and proliferative state [69]. Therefore, cytokeratin expression may be a common feature of primitive mesenchyme and reflect the stem cell nature of MSCs.
|
SUMMARY |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionSummaryReferences |
|---|
|
ACKNOWLEDGMENT |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionSummaryReferences |
|---|
|
REFERENCES |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionSummaryReferences |
|---|
-smooth muscle actin filaments. Lab Invest 1994;71:308–310.[Medline]This article has been cited by other articles:
|
|
 |
|
  B. Delorme, J. Ringe, C. Pontikoglou, J. Gaillard, A. Langonne, L. Sensebe, D. Noel, C. Jorgensen, T. Haupl, and P. Charbord Specific Lineage-Priming of Bone Marrow Mesenchymal Stem Cells Provides the Molecular Framework for Their Plasticity Stem Cells, May 1, 2009; 27(5): 1142 - 1151. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. Kubo, M. Shimizu, Y. Taya, T. Kawamoto, M. Michida, E. Kaneko, A. Igarashi, M. Nishimura, K. Segoshi, Y. Shimazu, et al. Identification of mesenchymal stem cell (MSC)-transcription factors by microarray and knockdown analyses, and signature molecule-marked MSC in bone marrow by immunohistochemistry Genes Cells, March 1, 2009; 14(3): 407 - 424. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Licheng Tan, Yiwang Chen, Yang Wang, Weihua Zhou, Xiangjun Zhu, Xiaohui He, Jiying Su, and Suping Cui In Vivo Evaluation of Butylene Terephthalate-ethylene Oxide-DL, Lactide Polymer as Porous Scaffolds for Tissue Engineering Journal of Bioactive and Compatible Polymers, January 1, 2009; 24(1): 43 - 55. [Abstract] [PDF]
|
|
|
|
 |
|
 R. Summer and A. Fine Mesenchymal Progenitor Cell Research: Limitations and Recommendations Proceedings of the ATS, August 15, 2008; 5(6): 707 - 710. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Y. Tayyareci, M. Sezer, B. Umman, S. Besisik, A. Mudun, Y. Sanli, A. Oncul, N. Gurses, D. Sargin, M. Meric, et al. Intracoronary Autologous Bone Marrow-Derived Mononuclear Cell Transplantation Improves Coronary Collateral Vessel Formation and Recruitment Capacity in Patients With Ischemic Cardiomyopathy: A Combined Hemodynamic and Scintigraphic Approach Angiology, May 1, 2008; 59(2): 145 - 155. [Abstract] [PDF]
|
|
|
|
|
|
I. A. Isakova, K. Baker, M. DuTreil, J. Dufour, D. Gaupp, and D. G. Phinney Age- and Dose-Related Effects on MSC Engraftment Levels and Anatomical Distribution in the Central Nervous Systems of Nonhuman Primates: Identification of Novel MSC Subpopulations That Respond to Guidance Cues in Brain Stem Cells, December 1, 2007; 25(12): 3261 - 3270. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. Tao, C.-P. Lau, H.-F. Tse, and G.-R. Li Functional ion channels in mouse bone marrow mesenchymal stem cells Am J Physiol Cell Physiol, November 1, 2007; 293(5): C1561 - C1567. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
D. G. Phinney and D. J. Prockop Concise Review: Mesenchymal Stem/Multipotent Stromal Cells: The State of Transdifferentiation and Modes of Tissue Repair Current Views Stem Cells, November 1, 2007; 25(11): 2896 - 2902. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. A. Ortiz, M. DuTreil, C. Fattman, A. C. Pandey, G. Torres, K. Go, and D. G. Phinney Interleukin 1 receptor antagonist mediates the antiinflammatory and antifibrotic effect of mesenchymal stem cells during lung injury PNAS, June 26, 2007; 104(26): 11002 - 11007. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Tomita, T. Mori, K. Maruyama, T. Zahir, M. Ward, A. Umezawa, and M. J. Young A Comparison of Neural Differentiation and Retinal Transplantation with Bone Marrow-Derived Cells and Retinal Progenitor Cells Stem Cells, October 1, 2006; 24(10): 2270 - 2278. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. N. Olivier, A. C. Rybicki, and E. E. Bouhassira Differentiation of Human Embryonic Stem Cells into Bipotent Mesenchymal Stem Cells Stem Cells, August 1, 2006; 24(8): 1914 - 1922. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. Song, N. E. Webb, Y. Song, and R. S. Tuan Identification and Functional Analysis of Candidate Genes Regulating Mesenchymal Stem Cell Self-Renewal and Multipotency Stem Cells, July 1, 2006; 24(7): 1707 - 1718. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. A. Gregory, J. Ylostalo, and D. J. Prockop Adult Bone Marrow Stem/Progenitor Cells (MSCs) Are Preconditioned by Microenvironmental "Niches" in Culture: A Two-Stage Hypothesis for Regulation of MSC Fate Sci. Signal., July 26, 2005; 2005(294): pe37 - pe37. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. Egusa, F. E. Schweizer, C.-C. Wang, Y. Matsuka, and I. Nishimura Neuronal Differentiation of Bone Marrow-derived Stromal Stem Cells Involves Suppression of Discordant Phenotypes through Gene Silencing J. Biol. Chem., June 24, 2005; 280(25): 23691 - 23697. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. J. Katz, A. Tholpady, S. S. Tholpady, H. Shang, and R. C. Ogle Cell Surface and Transcriptional Characterization of Human Adipose-Derived Adherent Stromal (hADAS) Cells Stem Cells, March 1, 2005; 23(3): 412 - 423. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. R. Rao and S. L. Stice Gene Expression Profiling of Embryonic Stem Cells Leads to Greater Understanding of Pluripotency and Early Developmental Events Biol Reprod, December 1, 2004; 71(6): 1772 - 1778. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. Kinnaird, E. Stabile, M. S. Burnett, and S. E. Epstein Bone Marrow-Derived Cells for Enhancing Collateral Development: Mechanisms, Animal Data, and Initial Clinical Experiences Circ. Res., August 20, 2004; 95(4): 354 - 363. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. D'Ippolito, S. Diabira, G. A. Howard, P. Menei, B. A. Roos, and P. C. Schiller Marrow-isolated adult multilineage inducible (MIAMI) cells, a unique population of postnatal young and old human cells with extensive expansion and differentiation potential J. Cell Sci., June 15, 2004; 117(14): 2971 - 2981. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. Oswald, S. Boxberger, B. Jorgensen, S. Feldmann, G. Ehninger, M. Bornhauser, and C. Werner Mesenchymal Stem Cells Can Be Differentiated Into Endothelial Cells In Vitro Stem Cells, May 1, 2004; 22(3): 377 - 384. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. G. Sylvester and M. T. Longaker Stem Cells: Review and Update Arch Surg, January 1, 2004; 139(1): 93 - 99. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Y. Tintut, Z. Alfonso, T. Saini, K. Radcliff, K. Watson, K. Bostrom, and L. L. Demer Multilineage Potential of Cells From the Artery Wall Circulation, November 18, 2003; 108(20): 2505 - 2510. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
W. A. Silva Jr., D. T. Covas, R. A. Panepucci, R. Proto-Siqueira, J. L.C. Siufi, D. L. Zanette, A. R.D. Santos, and M. A. Zago The Profile of Gene Expression of Human Marrow Mesenchymal Stem Cells Stem Cells, November 1, 2003; 21(6): 661 - 669. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. L. Spees, S. D. Olson, J. Ylostalo, P. J. Lynch, J. Smith, A. Perry, A. Peister, M. Y. Wang, and D. J. Prockop Differentiation, cell fusion, and nuclear fusion during ex vivo repair of epithelium by human adult stem cells from bone marrow stroma PNAS, March 4, 2003; 100(5): 2397 - 2402. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| STEM CELLS | THE ONCOLOGIST | CME | ALPHAMED PRESS JOURNALS |
