As the theory of stem cell plasticity was first proposed, we have explored an alternative hypothesis for this phenomenon: namely that adult bone marrow (BM) and umbilical cord blood (UCB) contain more developmentally primitive cells than hematopoietic stem cells (HSCs). In support of this notion, using multiparameter sorting we were able to isolate small Sca1+Lin-CD45- cells and CD133+Lin-CD45- cells from murine BM and human UCB, respectively, which were further enriched for the detection of various early developmental markers such as the SSEA antigen on the surface and the Oct4 and Nanog transcription factors in the nucleus. Similar populations of cells have been found in various organs by our team and others, including the heart, brain and gonads. Owing to their primitive cellular features, such as the high nuclear/cytoplasm ratio and the presence of euchromatin, they are called very small embryonic-like stem cells (VSELs). In the appropriate in vivo models, VSELs differentiate into long-term repopulating HSCs, mesenchymal stem cells (MSCs), lung epithelial cells, cardiomyocytes and gametes. In this review, we discuss the most recent data from our laboratory and other groups regarding the optimal isolation procedures and describe the updated molecular characteristics of VSELs.
Animals ; Cell Lineage ; Cell Separation/*methods ; Embryonic Stem Cells/*cytology/metabolism ; Hematopoietic Stem Cells/*cytology/metabolism ; Humans ; Mesenchymal Stromal Cells/*cytology/metabolism ; Pluripotent Stem Cells/cytology/metabolism

Stem cells are used for the investigation of developmental processes at both cellular and organism levels and offer tremendous potentials for clinical applications as an unlimited source for transplantation. Gangliosides, sialic acid-conjugated glycosphingolipids, play important regulatory roles in cell proliferation and differentiation. However, their expression patterns in stem cells and during neuronal differentiation are not known. Here, we investigated expression of gangliosides during the growth of mouse embryonic stem cells (mESCs), mesenchymal stem cells (MSCs) and differentiated neuronal cells by using high-performance thin-layer chromatography (HPTLC). Monosialoganglioside 1 (GM1) was expressed in mESCs and MSCs, while GM3 and GD3 were expressed in embryonic bodies. In the 9-day old differentiated neuronal cells from mESCs cells and MSCs, GM1 and GT1b were expressed. Results from immunostaining were consistent with those observed by HPTLC assay. These suggest that gangliosides are specifically expressed according to differentiation of mESCs and MSCs into neuronal cells and expressional difference of gangliosides may be a useful marker to identify differentiation of mESCs and MSCs into neuronal cells.
Neurons/*cytology/*metabolism ; Mice ; Mesenchymal Stem Cells/*cytology/*metabolism ; Gangliosides/*metabolism ; Embryonic Stem Cells/*cytology/*metabolism ; Cells, Cultured ; Cell Differentiation ; Animals

The study was aimed to explore the influence of co-culture ex vivo of CD34+ cells from two units of cord blood (CB) on the homing-related adherent molecule expression of each other. Mesenchymal stem cells (MSCs) were obtained from human bone marrow. Two units of CB CD34+ cells were co-cultured on 12 Gy gamma-ray irradiated MSC layer. Their adherent molecule expressions were assessed by flow cytometry. The results showed that the purity of the isolated CD34+ cells was (98.25+/-0.93)%. After co-culture on MSC layer for 6 days, the proportion of CD34+ cells of each unit was dropped to (60.4+/-6.32)% and (60.2+/-5.12)% respectively, but there was no significant difference from the control groups. The expressions of CD44, CD62L, CD184 and CD26 on CD34+ cells of each unit remained unaffected. The expression of CD162 was downregulated and CD54 was first increased but then dropped to the level before co-culture. But there was no significant difference between the experimental and control groups. In conclusion, co-culture of CD34+ cells from two units of CB may have no effects on the adherent molecule expressions of each other.
Antigens, CD34 ; metabolism ; Bone Marrow Cells ; cytology ; Cell Adhesion Molecules ; metabolism ; Coculture Techniques ; Fetal Blood ; cytology ; metabolism ; Hematopoietic Stem Cells ; cytology ; metabolism ; Humans ; Mesenchymal Stromal Cells ; cytology

OBJECTIVE: To establish an in vitro method to culture mesenchymal stem cells(MSCs) derived from human nasal mucosa, and explore their stemness and differentiation potential. METHOD: Based on the observation of distribution of MSCs in human nasal mucosa, we cultured and proliferated MSCs in vitro and identified the expression of stem cell markers on them including Nestin, CD133, Vimentin and Sa114 with immunofluorescence. The MSCs were induced to differentiate to osteoblasts with medium containing dexamethasone, ascorbic acid and beta sodium glycerophosphate, and to neurons with Neurobasal medium containing B27, ATRA and TSA. Histochemistry and immunofluorescence were applied to evaluate the differentiation. RESULT: The nestin and vimentin immunofluorescence-positive MSCs existed extensively in human nasal mucosa. While the MSCs were cultured in the osteogenic-inducing medium, activities of alkaline phosphatase were increased significantly, and bone nodules were found on the surface of the osteoblasts by alizarin red staining. After the induction by neural-inducing medium, the MSCs adopted neuron like appearance with many slim protrusions interconnected as a network. The induced cells expressed neural markers NF-200 and BM88 strongly. CONCLUSION The MSCs derived from human nasal mucosa are multipotent stem cells and can be utilized as seed cells to repair bone or neural injury.
Alkaline Phosphatase ; metabolism ; Cell Differentiation ; Cell Proliferation ; Cells, Cultured ; Humans ; Mesenchymal Stem Cells ; cytology ; metabolism ; Multipotent Stem Cells ; Nasal Mucosa ; cytology ; Neurons ; Osteoblasts ; cytology

OBJECTIVETo investigate the telomerase activity of human adipose derived stem cells (ADSCs) during proliferation and differentiation in vitro.

METHODSADSCs were highly purified and cultured in vitro. The morphology, phenotype and biological properties of the cultured ADSCs were observed by flow cytometer. Then ADSCs were induced to differentiate into adipocytes and osteoblast. The telomerase activity was detected by TRAP.

RESULTSADSCs had the ability of multi-directed differentiation, like adipocytes and osteoblast. It could also express the stem cell-related surface markers. The telomerase activity was negative or lowly expressed in ADSCs in vitro within 12 generations. The telomerase activity was up-regulated when ADSCs was adipogenic differentiated, but deceased 3-6 days later.

CONCLUSIONSThe telomerase activity of ADSCs is not changed during culture in vitro. It is up-regulated when ADSCs are induced to adipogenic differentiation, but decreased later.

Adipocytes ; cytology ; metabolism ; Adult ; Cell Differentiation ; Cell Proliferation ; Cells, Cultured ; Female ; Humans ; Mesenchymal Stromal Cells ; cytology ; metabolism ; Stem Cells ; cytology ; metabolism ; Telomerase ; metabolism ; Young Adult

In this study, we evaluated the biological properties of human mesenchymal stem cells transfected (hMSC) with a plasmid vector expressing human cytokine interleukin-12 (IL-12). Surface markers were analysed by immunophenotyping using flow cytometry. Differentiation capability was evaluated towards adipogenesis and osteogenesis. We demonstrated that successfully transfected hMSC retained their surface immunophenotypes and differentiation potential into adipocytes and osteocytes. These results indicate that hMSC may be a suitable vehicle for gene transduction.
Antigens, Surface/metabolism ; Biological Markers/metabolism ; Bone Marrow Cells/cytology ; Bone Marrow Cells/metabolism ; Cell Differentiation/physiology ; Cells, Cultured ; Flow Cytometry ; Immunophenotyping ; Interleukin-12/genetics ; Interleukin-12/metabolism ; Mesenchymal Stem Cells/*cytology ; Mesenchymal Stem Cells/metabolism ; Transfection

Mesenchymal stem cells (MSCs) are partially defined by their ability to differentiate into tissues including bone, cartilage and adipose in vitro, but it is their trophic, paracrine and immunomodulatory functions that may have the greatest therapeutic impact in vivo. Unlike pharmaceutical treatments that deliver a single agent at a specific dose, MSCs are site regulated and secrete bioactive factors and signals at variable concentrations in response to local microenvironmental cues. Significant progress has been made in understanding the biochemical and metabolic mechanisms and feedback associated with MSC response. The anti-inflammatory and immunomodulatory capacity of MSC may be paramount in the restoration of localized or systemic conditions for normal healing and tissue regeneration. Allogeneic MSC treatments, categorized as a drug by regulatory agencies, have been widely pursued, but new studies demonstrate the efficacy of autologous MSC therapies, even for individuals affected by a disease state. Safety and regulatory concerns surrounding allogeneic cell preparations make autologous and minimally manipulated cell therapies an attractive option for many regenerative, anti-inflammatory and autoimmune applications.
Animals ; *Cellular Microenvironment ; Humans ; *Mesenchymal Stem Cell Transplantation ; Mesenchymal Stromal Cells/cytology/immunology/*metabolism ; Regenerative Medicine/*methods

Bone marrow mesenchymal stem cells (MSCs) are defined as pluripotent cells which have high self-renewal capacity and multipotentiality for differentiation. Because of their characteristics of supporting hematopoietisis, multipotentiality for differentiation and their possible use for both cell and gene engineerings, MSCs will have important value in clinic use.
Animals ; Cell Differentiation ; genetics ; physiology ; Humans ; Mesenchymal Stem Cell Transplantation ; Mesenchymal Stromal Cells ; cytology ; metabolism ; physiology ; Models, Biological

Mesenchymal stem cells (MSCs) are capable of self-renewal and differentiation into lineages of mesenchymal tissues that are currently under investigation for a variety of therapeutic applications. The purpose of this study was to compare cytokine gene expression in MSCs from human placenta, cord blood (CB) and bone marrow (BM). The cytokine expression profiles of MSCs from BM, CB and placenta (amnion, decidua) were compared by proteome profiler array analysis. The cytokines that were expressed differently, in each type of MSC, were analyzed by real-time PCR. We evaluated 36 cytokines. Most types of MSCs had a common expression pattern including MIF (GIF, DER6), IL-8 (CXCL8), Serpin E1 (PAI-1), GROalpha(CXCL1), and IL-6. MCP-1, however, was expressed in both the MSCs from the BM and the amnion. sICAM-1 was expressed in both the amnion and decidua MSCs. SDF-1 was expressed only in the BM MSCs. Real-time PCR demonstrated the expression of the cytokines in each of the MSCs. The MSCs from bone marrow, placenta (amnion and decidua) and cord blood expressed the cytokines differently. These results suggest that cytokine induction and signal transduction are different in MSCs from different tissues.
Bone Marrow Cells/*cytology ; Cytokines/genetics/*metabolism ; Female ; Fetal Blood/*cytology ; Gene Expression Profiling ; Humans ; Mesenchymal Stem Cells/cytology/*metabolism ; Placenta/*cytology ; Pregnancy ; Protein Array Analysis

Mesenchymal stem cells possess the ability of self-renewal and multiple differentiation potential, thus exert immunomodulatory effect during tissue repair. Mesenchymal stem cells can stimulate angiogenesis and promote tissue repair through transdifferentiation and secreting a variety of growth factors and cytokines. This review outlines the advances in the mechanism of mesenchymal stem cells in promoting wound healing, including alleviation of inflammatory response, induction of angiogenesis, and promotion of migration of mesenchymal stem cells to the site of tissue injury.
Cell Differentiation ; Cell Transdifferentiation ; Mesenchymal Stem Cell Transplantation ; methods ; Mesenchymal Stromal Cells ; cytology ; metabolism ; physiology ; Skin ; cytology ; metabolism ; Wound Healing ; physiology