Source Of Adult Stem Cells Research Articles

Isolation of autologous adipose tissue-derived mesenchymal stem cells for bone repair

IntroductionAdipose tissue represents an abundant and accessible source of adult stem cells that can differentiate into cells and tissues of mesodermal origin, including osteogenic cells. MethodsThis paper describes the procedure to obtain a 5-cm3 saline sample, containing the adipose-derived stem cells (ASCs) pellet, starting from lipoaspirate obtained from a conventional abdominal liposuction. ResultsA mean of 2.5×106 cells is isolated for each procedure; 35% (875000) of these are CD34+/CD45− cells, which express a subset of both positive (CD10, CD13, CD44, CD59, CD73, CD90, HLAABC) and negative (CD33, CD39, CD102, CD106, CD146, HLADR) cell-associated surface antigens, characterizing them as ASCs. ConclusionsThis procedure is easy, effective, economic and safe. It allows the harvesting of a significant number of ASCs that are ready for one-step bony regenerative surgical procedures.

Erratum to: Donor age and long-term culture do not negatively influence the stem potential of limbal fibroblast-like stem cells

In regenerative medicine the maintenance of stem cell properties is of crucial importance. Ageing is considered a cause of reduced stemness capability. The limbus is a stem niche of easy access and harbors two stem cell populations: epithelial stem cells and fibroblast-like stem cells. Our aim was to investigate whether donor age and/or long-term culture have any influence on stem cell marker expression and the profiles in the fibroblast-like stem cell population. Fibroblast-like stem cells were isolated and digested from 25 limbus samples of normal human corneo-scleral rings and long-term cultures were obtained. SSEA4 expression and sphere-forming capability were evaluated; cytofluorimetric assay was performed to detect the immunophenotypes HLA-DR, CD45, and CD34 and the principle stem cell markers ABCG2, OCT3/4, and NANOG. Molecular expression of the principal mesenchymal stem cell genes was investigated by real-time PCR. Two-dimensional gel electrophoresis and mass spectrometric sequencing were performed and a stable proteomic profile was identified. The proteins detected were explored by gene ontology and STRING analysis. The data were reported as means ± SD, compared by Student’s unpaired t test and considering p < 0.05 as statistically significant. The isolated cells did not display any hematopoietic surface marker (CD34 and CD45) and HLA-DR and they maintained these features in long-term culture. The expression of the stemness genes and the multilineage differentiation under in-vitro culture conditions proved to be well maintained. Proteomic analysis revealed a fibroblast-like stem cell profile of 164 proteins with higher expression levels. Eighty of these showed stable expression levels and were involved in maintenance of “the stem gene profile”; 84 were differentially expressed and were involved in structural activity. The fibroblast-like limbal stem cells confirmed that they are a robust source of adult stem cells and that they have good plasticity, good proliferative capability, and long-term maintenance of stem cell properties, independently of donor age and long-term culture conditions. Our findings confirm that limbal fibroblast-like stem cells are highly promising for application in regenerative medicine and that in-vitro culture steps do not influence their stem cell properties. Moreover, the proteomic data enrich our knowledge of fibroblast-like stem cells.

Amniotic membrane mesenchymal stem cells can differentiate into germ cells in vitro.

This is the first report on differentiation of mouse amniotic membrane mesenchymal stem cells (AM-MSCs) into male germ cells (GCs). AM-MSCs have the multipotent differentiation capacity and can be differentiated into various cell types. In the present study, AM-MSCs were induced for differentiation into GCs. AM-MSCs were isolated from mouse embryonic membrane by enzymatic digestion. AM-MSCs were characterized with osteogenic and adipogenic differentiation test and flow cytometric analysis of some CD-markers. AM-MSCs were induced to differentiate into GCs using a creative two-step method. Passage-3 AM-MSCs were firstly treated with 25ng/ml bone morphogenetic protein 4 (BMP4) for 5d and in continuing with 1μM retinoic acid (RA) for 12d (total treatment time was 17d). At the end of the treatment period, real-time reverse transcription (RT)-PCR was performed to evaluate the expression of GC-specific markers-Itgb1, Dazl, Stra8, Piwil2, Mvh, Oct4, and c-Kit- in the cells. Moreover, flow cytometry and immunofluorescence staining were performed to evaluate the expression of Mvh and Dazl at protein level. Real-time RT-PCR showed that most of the tested markers were upregulated in the treated AM-MSCs. Furthermore, flow cytometric and immunofluorescence analyses both revealed that a considerable part of the treated cells expressed GC-specific markers. The percentage of positive cells for Mvh and Dazl was about 23 and 46%, respectively. Our results indicated that a number of AM-MSCs successfully differentiated into the GCs. Finally, it seems that AM-MSCs would be a potential source of adult pluripotent stem cells for in vitro generation of GCs and cell-based therapies for treatment of infertility.

Fibroblast growth factor and vascular endothelial growth factor play a critical role in endotheliogenesis from human adipose-derived stem cells

Adipose-derived stem cells (ASCs) are a potential adult mesenchymal stem cell source for restoring endothelial function in patients with critical limb ischemia. Fibroblast growth factor 2 (FGF2) and vascular endothelial growth factor (VEGF) play a major role in angiogenesis and wound healing. This study evaluated the effects of FGF and VEGF on the proliferation, migration, and potential endothelial differentiation of human ASCs with regards to their use as endothelial cell substitutes. ASCs were isolated from clinical lipoaspirates and cultured in M199 medium with fetal bovine serum (10%), FGF2 (10ng/mL), VEGF (50ng/mL), or combinations of FGF2 and VEGF. Cell proliferation rates, viability, and migration were measured by growth curves, MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide), and scratch assays. For cell attachment determinations, ASCs were seeded onto a scaffold of small intestinal submucosa for 5days. Endothelial differentiation capabilities of ASCs were confirmed by expression of endothelial cell-specific markers using quantitative polymerase chain reaction, immunofluorescence staining, and cord formation on Matrigel (BD Biosciences, San Jose, Calif). PD173074, a selective inhibitor of FGF receptor, was used to confirm the importance of FGF signaling. ASCs treated with FGF or combinations of FGF and VEGF showed increased proliferation rates and consistent differentiation toward an endothelial cell lineage increase in platelet endothelial cell adhesion molecule (CD31), von Willebrand factor, endothelial nitric oxide synthase, and vascular endothelial cadherin message, and in protein and cord formation on Matrigel. FGF and VEGF stimulated ASC migration and increased the attachment and retention after seeding onto a matrix graft of small intestinal submucosa. Blockade of FGF signaling with PD173074 abrogated ASC endothelial cell differentiation potential. These results indicate that FGF and VEGF are ASC promoters for proliferation, migration, attachment, and endothelial differentiation. FGF and VEGF have a costimulatory effect on ASC endotheliogenesis. These results further suggest that ASCs with enhanced FGF signaling may potentially be used for tissue engineering and cell-based therapies in patients with critical limb ischemia.

Strategies to Optimize Adult Stem Cell Therapy for Tissue Regeneration.

Stem cell therapy aims to replace damaged or aged cells with healthy functioning cells in congenital defects, tissue injuries, autoimmune disorders, and neurogenic degenerative diseases. Among various types of stem cells, adult stem cells (i.e., tissue-specific stem cells) commit to becoming the functional cells from their tissue of origin. These cells are the most commonly used in cell-based therapy since they do not confer risk of teratomas, do not require fetal stem cell maneuvers and thus are free of ethical concerns, and they confer low immunogenicity (even if allogenous). The goal of this review is to summarize the current state of the art and advances in using stem cell therapy for tissue repair in solid organs. Here we address key factors in cell preparation, such as the source of adult stem cells, optimal cell types for implantation (universal mesenchymal stem cells vs. tissue-specific stem cells, or induced vs. non-induced stem cells), early or late passages of stem cells, stem cells with endogenous or exogenous growth factors, preconditioning of stem cells (hypoxia, growth factors, or conditioned medium), using various controlled release systems to deliver growth factors with hydrogels or microspheres to provide apposite interactions of stem cells and their niche. We also review several approaches of cell delivery that affect the outcomes of cell therapy, including the appropriate routes of cell administration (systemic, intravenous, or intraperitoneal vs. local administration), timing for cell therapy (immediate vs. a few days after injury), single injection of a large number of cells vs. multiple smaller injections, a single site for injection vs. multiple sites and use of rodents vs. larger animal models. Future directions of stem cell-based therapies are also discussed to guide potential clinical applications.

Identification of Radial Glia Progenitors in the Developing and Adult Retina of Sharks.

Neural stem cells give rise to transient progenitors termed neuroepithelial cells (NECs) and radial glial cells (RGCs). RGCs represent the major source of neurons, glia and adult stem cells in several regions of the central nervous system (CNS). RGCs are mostly transient in mammals, but they are widely maintained in the adult CNS of fishes, where they continue to be morphologically similar to RGCs in the mammalian brain and fulfill similar roles as progenitors and guide for migrating neurons. The retina of fishes offers an exceptional model to approach the study of adult neurogenesis because of the presence of constitutive proliferation from the ciliary marginal zone (CMZ), containing NECs, and from adult glial cells with radial morphology (the Müller glia). However, the cellular hierarchies and precise contribution of different types of progenitors to adult neurogenesis remain unsolved. We have analyzed the transition from NECs to RGCs and RGC differentiation in the retina of the cartilaginous fish Scyliorhinus canicula, which offers a particularly good spatial and temporal frame to investigate this process. We have characterized progenitor and adult RGCs by immunohistochemical detection of glial markers as glial fibrillary acidic protein (GFAP) and glutamine synthetase (GS). We have compared the emergence and localization of glial markers with that of proliferating cell nuclear antigen (PCNA, a proliferation maker) and Doublecortin (DCX, which increases at early stages of neuronal differentiation). During retinal development, GFAP-immunoreactive NECs located in the most peripheral CMZ (CMZp) codistribute with DCX-immunonegative cells. GFAP-immunoreactive RGCs and Müller cells are located in successive more central parts of the retina and codistribute with DCX- and DCX/GS-immunoreactive cells, respectively. The same types of progenitors are found in juveniles, suggesting that the contribution of the CMZ to adult neurogenesis implies a transition through the radial glia (RG) state.

Donor age and long-term culture do not negatively influence the stem potential of limbal fibroblast-like stem cells.

BackgroundIn regenerative medicine the maintenance of stem cell properties is of crucial importance. Ageing is considered a cause of reduced stemness capability. The limbus is a stem niche of easy access and harbors two stem cell populations: epithelial stem cells and fibroblast-like stem cells. Our aim was to investigate whether donor age and/or long-term culture have any influence on stem cell marker expression and the profiles in the fibroblast-like stem cell population.MethodsFibroblast-like stem cells were isolated and digested from 25 limbus samples of normal human corneo-scleral rings and long-term cultures were obtained. SSEA4 expression and sphere-forming capability were evaluated; cytofluorimetric assay was performed to detect the immunophenotypes HLA-DR, CD45, and CD34 and the principle stem cell markers ABCG2, OCT3/4, and NANOG. Molecular expression of the principal mesenchymal stem cell genes was investigated by real-time PCR. Two-dimensional gel electrophoresis and mass spectrometric sequencing were performed and a stable proteomic profile was identified. The proteins detected were explored by gene ontology and STRING analysis. The data were reported as means ± SD, compared by Student’s unpaired t test and considering p < 0.05 as statistically significant.ResultsThe isolated cells did not display any hematopoietic surface marker (CD34 and CD45) and HLA-DR and they maintained these features in long-term culture. The expression of the stemness genes and the multilineage differentiation under in-vitro culture conditions proved to be well maintained. Proteomic analysis revealed a fibroblast-like stem cell profile of 164 proteins with higher expression levels. Eighty of these showed stable expression levels and were involved in maintenance of “the stem gene profile”; 84 were differentially expressed and were involved in structural activity.ConclusionsThe fibroblast-like limbal stem cells confirmed that they are a robust source of adult stem cells and that they have good plasticity, good proliferative capability, and long-term maintenance of stem cell properties, independently of donor age and long-term culture conditions. Our findings confirm that limbal fibroblast-like stem cells are highly promising for application in regenerative medicine and that in-vitro culture steps do not influence their stem cell properties. Moreover, the proteomic data enrich our knowledge of fibroblast-like stem cells.Electronic supplementary materialThe online version of this article (doi:10.1186/s13287-016-0342-z) contains supplementary material, which is available to authorized users.

In vitro differentiation of endometrial regenerative cells into smooth muscle cells: Α potential approach for the management of pelvic organ prolapse.

Pelvic organ prolapse (POP), is a common condition in parous women. Synthetic mesh was once considered to be the standard of care; however, the use of synthetic mesh is limited by severe complications, thus creating a need for novel approaches. The application of cell-based therapy with stem cells may be an ideal alternative, and specifically for vaginal prolapse. Abnormalities in vaginal smooth muscle (SM) play a role in the pathogenesis of POP, indicating that smooth muscle cells (SMCs) may be a potential therapeutic target. Endometrial regenerative cells (ERCs) are an easily accessible, readily available source of adult stem cells. In the present study, ERCs were obtained from human menstrual blood, and phase contrast microscopy and flow cytometry were performed to characterize the morphology and phenotype of the ERCs. SMC differentiation was induced by a transforming growth factor β1-based medium, and the induction conditions were optimized. We defined the SMC characteristics of the induced cells with regard to morphology and marker expression using transmission electron microscopy, western blot analysis, immunocytofluorescence and RT-PCR. Examining the expression of the components of the Smad pathway and phosphorylated Smad2 and Smad3 by western blot analysis, RT-PCR and quantitative PCR demonstrated that the 'TGFBR2/ALK5/Smad2 and Smad3' pathway is involved, and both Smad2 and Smad3 participated in SMC differentiation. Taken together, these findings indicate that ERCs may be a promising cell source for cellular therapy aimed at modulating SM function in the vagina wall and pelvic floor in order to treat POP.

Adipose-Derived Stem Cells as a Tool in Cell-Based Therapies.

Recent development in stem cell isolation methods and expansion under laboratory conditions create an opportunity to use those aforementioned cells in tissue engineering and regenerative medicine. Particular attention is drawn towards mesenchymal stem cells (MSCs) being multipotent progenitors exhibiting several unique characteristics, including high proliferation potential, self-renewal abilities and multilineage differentiation into cells of mesodermal and non-mesodermal origin. High abundance of MSCs found in adipose tissue makes it a very attractive source of adult stem cells for further use in regenerative medicine applications. Despite immunomodulating properties of adipose-derived stem cells (ASCs) and a secretion of a wide variety of paracrine factors that facilitate tissue regeneration, effectiveness of stem cell therapy was not supported by the results of clinical trials. Lack of a single, universal stem cell marker, patient-to-patient variability, heterogeneity of ASC population combined with multiple widely different protocols of cell isolation and expansion hinder the ability to precisely identify and analyze biological properties of stem cells. The above issues contribute to conflicting data reported in literature. We will review the comprehensive information concerning characteristic features of ASCs. We will also review the regenerative potential and clinical application based on various clinical trials.

Therapeutic Effect of Ligustilide-Stimulated Adipose-Derived Stem Cells in a Mouse Thromboembolic Stroke Model.

Stroke is a result of cerebral ischemia that triggers a cascade of both physiological and biochemical events. No effective treatment is available for stroke; however, stem cells have the potential to rescue tissue from the effects of stroke. Adipose-derived stem cells (ADSCs) are an abundant source of adult stem cells; therefore, ADSC therapy can be considered as a future strategy for regenerative medicine. However, more research is required to improve the effectiveness of transplanted ADSCs as a treatment for stroke in the mouse stroke model. Ligustilide, isolated from the herb Angelica sinensis, exhibits a protective effect on neurons and inhibits inflammation. We also demonstrated that ligustilide treatment increases the expression levels of homing factors such as SDF-1 and CXCR4. In the present study, we evaluated the therapeutic effects of ADSC transplantation and ligustilide treatment in a mouse thromboembolic stroke model by behavioral tests, including beam walking, locomotor activity, and rotarod analysis. ADSCs pretreated with ligustilide were transplanted into the brains of stroke mice. The results showed that the therapeutic effect of ADSCs pretreated with ligustilide was better than that of ADSCs without ligustilide pretreatment. There was no difference between the recovery of mice treated by ADSC transplantation combined with subcutaneous ligustilide injection and that of mice treated only with ADSCs. The TUNEL assay showed fewer apoptotic cells in the brains of mice transplanted with ADSCs pretreated with ligustilide as well as in those without pretreatment. In summary, pretreatment of ADSCs with ligustilide improves the therapeutic efficacy of ADSC transplantation. The results of this study will help improve stem cell therapies being developed for future clinical applications.

Mesenchymal Stem Cells and Their Clinical Applications in Osteoarthritis.

Osteoarthritis is a chronic degenerative joint disorder characterized by articular cartilage destruction and osteophyte formation. Chondrocytes in the matrix have a relatively slow turnover rate, and the tissue itself lacks a blood supply to support repair and remodeling. Researchers have evaluated the effectiveness of stem cell therapy and tissue engineering for treating osteoarthritis. All sources of stem cells, including embryonic, induced pluripotent, fetal, and adult stem cells, have potential use in stem cell therapy, which provides a permanent biological solution. Mesenchymal stem cells (MSCs) isolated from bone marrow, adipose tissue, and umbilical cord show considerable promise for use in cartilage repair. MSCs can be sourced from any or all joint tissues and can modulate the immune response. Additionally, MSCs can directly differentiate into chondrocytes under appropriate signal transduction. They also have immunosuppressive and anti-inflammatory paracrine effects. This article reviews the current clinical applications of MSCs and future directions of research in osteoarthritis.

Células madre y progenitoras para la reparación de cartílago articular

Cartilage is a sensitive tissue prone to damage with the continuous practice of sports and ageing process, holding a low self repairing capacity. Degenerative joint diseases are among the most disabling and limiting in regards to life quality and daily activities. Biological therapies have become available to potentially treat osteoarthritis and focal chondral defects. However, there is still no efficient way to regenerate native hyaline cartilage. Stem cell therapy and bioengineering is a promising field which can transform the paradigms in orthopaedics. This review provides an overall view of the current state of biological therapies with stem and progenitor cells. We summarize cell therapy options with culture expanded cells and also four common sources of adult stem cells: bone marrow, adipose tissue, synovium and peripheral venous blood, along with clinical studies reporting their effectiveness. The purpose of this review is to summarize adult stem cells approaches for the treatment of focal chondral lesions and osteoarthritis.

Isolation and Differentiation of Adipose-Derived Stem Cells from Porcine Subcutaneous Adipose Tissues.

Obesity is an unconstrained worldwide epidemic. Unraveling molecular controls in adipose tissue development holds promise to treat obesity or diabetes. Although numerous immortalized adipogenic cell lines have been established, adipose-derived stem cells from the stromal vascular fraction of subcutaneous white adipose tissues provide a reliable cellular system ex vivo much closer to adipose development in vivo. Pig adipose-derived stem cells (pADSC) are isolated from 7- to 9-day old piglets. The dorsal white fat depot of porcine subcutaneous adipose tissues is sliced, minced and collagenase digested. These pADSC exhibit strong potential to differentiate into adipocytes. Moreover, the pADSC also possess multipotency, assessed by selective stem cell markers, to differentiate into various mesenchymal cell types including adipocytes, osteocytes, and chondrocytes. These pADSC can be used for clarification of molecular switches in regulating classical adipocyte differentiation or in direction to other mesenchymal cell types of mesodermal origin. Furthermore, extended lineages into cells of ectodermal and endodermal origin have recently been achieved. Therefore, pADSC derived in this protocol provide an abundant and assessable source of adult mesenchymal stem cells with full multipotency for studying adipose development and application to tissue engineering of regenerative medicine.

Isolation and Differentiation of Adipose-Derived Stem Cells from Porcine Subcutaneous Adipose Tissues

Obesity is an unconstrained worldwide epidemic. Unraveling molecular controls in adipose tissue development holds promise to treat obesity or diabetes. Although numerous immortalized adipogenic cell lines have been established, adipose-derived stem cells from the stromal vascular fraction of subcutaneous white adipose tissues provide a reliable cellular system ex vivo much closer to adipose development in vivo. Pig adipose-derived stem cells (pADSC) are isolated from 7- to 9-day old piglets. The dorsal white fat depot of porcine subcutaneous adipose tissues is sliced, minced and collagenase digested. These pADSC exhibit strong potential to differentiate into adipocytes. Moreover, the pADSC also possess multipotency, assessed by selective stem cell markers, to differentiate into various mesenchymal cell types including adipocytes, osteocytes, and chondrocytes. These pADSC can be used for clarification of molecular switches in regulating classical adipocyte differentiation or in direction to other mesenchymal cell types of mesodermal origin. Furthermore, extended lineages into cells of ectodermal and endodermal origin have recently been achieved. Therefore, pADSC derived in this protocol provide an abundant and assessable source of adult mesenchymal stem cells with full multipotency for studying adipose development and application to tissue engineering of regenerative medicine.

The frequency of multipotent CD133(+)CD45RA(-)CD34(+) hematopoietic stem cells is not increased in fetal liver compared with adult stem cell sources.

The cell surface marker CD133 has been used to describe a revised model of adult human hematopoiesis, with hematopoietic stem cells and multipotent progenitors (HSCs/MPPs: CD133(+)CD45RA(-)CD34(+)) giving rise to lymphomyeloid-primed progenitors (LMPPs: CD133(+)CD45RA(+)CD34(+)) and erythromyeloid progenitors (EMPs: CD133(low)CD45RA(-)CD34(+)). Because adult and fetal hematopoietic stem and progenitor cells (HSPCs) differ in their gene expression profile, differentiation capabilities, and cell surface marker expression, we were interested in whether the reported segregation of lineage potentials in adult human hematopoiesis would also apply to human fetal liver. CD133 expression was easily detected in human fetal liver cells, and the defined hematopoietic subpopulations were similar to those found for adult HSPCs. Fetal HSPCs were enriched for EMPs and HSCs/MPPs, which were primed toward erythromyeloid differentiation. However, the frequency of multipotent CD133(+)CD45RA(-)CD34(+) HSPCs was much lower than previously reported and comparable to that of umbilical cord blood. We noted that engraftment in NSG (NOD scid gamma [NOD.Cg-Prkdc(scid) Il2rg(tm1Wjl)/SzJ])mice was driven mostly by LMPPs, confirming recent findings that repopulation in mice is not a unique feature of multipotent HSCs/MPPs. Thus, our data challenge the general assumption that human fetal liver contains a greater percentage of multipotent HSCs/MPPs than any adult HSC source, and the mouse model may have to be re-evaluated with respect to the type of readout it provides.

Mesenchymal stem cell therapy for the streptozotocin-induced neurodegeneration in rats

Background and Aim: Bone marrow-derived mesenchymal stem cells (BM-MSCs) are one of the sources of adult stem cells being explored for potential use in repairing neurodegenerative disorders. In this study, it was aimed to investigate the useful effects of BM-MSCs therapy on the streptozotocin-induced neurodegeneration in rats.Materials and Methods: Adult female Wistar rats were bilaterally injected intra-cerebroventricularly with streptozotocin (3 mg/kg) for neurodegeneration. Water maze tests were used to monitor spatial learning and memory. One or two intravenous injections of BM-MSCs were administrated to rat via the tail veins. At the end of the study, all rats were sacrificed for histological evaluation and immunohistochemistry.Results: Streptozotocin group demonstrated a significant increase in escape latency in comparison with both control groups (Sham and Saline), whereas rats treated with BM-MSCs exhibited a decrease in escape latency in comparison with streptozotocin group. The percentage of time spent in the target quadrant and the mean number of platform crossings did not change in all the groups. BM-MSCs administration improved spatial learning but not memory. However, improvement in neuronal cells in hippocampal CA1 region was only observed in the rats treated with BM-MSCs twice as opposed to the rats treated with BM-MSCs once or with saline.Conclusions: In this study, mesenchymal stem cells therapy failed to improve the streptozotocin-induced neurodegeneration like Alzheimer’s disease in rats.

Erratum to: Differentiation of Human Endometrial Stem Cells into Schwann Cells in Fibrin Hydrogel as 3D Culture

Human endometrial stem cells (hEnSCs) are a new source of adult multipotent stem cells with the ability of differentiation into many cell lineages. Many stem cell sources are desirable for differentiation into Schwann cells. Schwann-like cells derived from hEnSCs may be one of the ideal alternative cell sources for Schwann cell generation. In this study, for differentiation of hEnSCs into Schwann cells, hEnSCs were induced with RA/FSK/PDGF-AA/HRG as an induction medium for 14 days. The cells were cultured in a tissue culture plate (TCP) and fibrin gel matrix. The viability of cultured cells in the fibrin gel and TCP was analyzed with 3-[4,5-dimethyl-2-thia-zolyl]-2, 5-diphenyl-2H-tetrazolium bromide (MTT) assay for 7 days. The attachment of cells was analyzed with SEM and DAPI staining. The expression of S100 and P75 as Schwann cell markers was evaluated by immunocytochemistry and quantitative real-time PCR (RT-PCR). The evaluation of the MTT assay and gene expression showed that the survival rate and differentiation of hEnSCs into Schwann cells in the fibrin gel were better than those in the TCP group. These results suggest that human EnSCs can be differentiated into Schwann cells in the fibrin gel better than in the TCP, and the fibrin gel might provide a suitable three-dimensional (3D) scaffold for clinical applications for cell therapy of the nervous system.

Peripheral-Nerve and Spinal-Cord Regeneration in Mice Using Hair-Follicle-Associated Pluripotent (HAP) Stem Cells.

Nestin, a neural stem cell marker protein, is expressed in hair follicle cells above the bulge area. These nestin-positive hair follicle-associated-pluripotent (HAP) stem cells are negative for the keratinocyte marker K15 and can differentiate into neurons, glia, keratinocytes, smooth muscle cells, cardiac muscle cells, and melanocytes in vitro. HAP stem cells are positive for the stem cell marker CD34, as well as K15-negative, suggesting their relatively undifferentiated state. HAP stem cells promoted the functional recovery of injured peripheral nerves and the spinal cord. HAP stem cells differentiated into glial fibrillary acidic protein (GFAP)-positive Schwann cells when implanted in severed sciatic nerves and spinal cords in mice. These results suggest that HAP stem cells provide an important accessible, autologous source of adult stem cells for regenerative medicine, that have critical advantages over ES and iPS stem cells.

Dental Medical Waste, Promising Source of Adult Stem Cells for Tissue Regeneration

Dental Medical Waste, Promising Source of Adult Stem Cells for Tissue Regeneration

Isolation, Culture, and Characterization of Human Umbilical Cord Blood-Derived Mesenchymal Stromal Cells.

Umbilical cord blood (CB) is considered one of the youngest available sources of adult stem cells. Besides hematopoietic stem cells, CB has been shown to contain endothelial progenitor cells as well as mesenchymal stromal/stem cells (MSC). To isolate MSC from cord blood, CB is collected into a sterile bag containing the anticoagulant citrate-phosphate-dextrose (CPD). The CB is then processed by density-gradient centrifugation to obtain mononuclear cells (MNC). These are cultured until the outgrowth of fibroblastoid cell colonies appears. After reaching a subconfluent stage, cells are harvested, expanded, and characterized as cord blood mesenchymal stromal cells (CB-MSC) according to standard criteria: plastic adherence, fibroblast morphology, CFU-f assay, proliferation potential, immune phenotype, and differentiation potential.Apparently, the frequency of MSC in CB is extremely low. Thus, not every CB unit will provide adequate MSC isolation yields. Different strategies have been proposed aiming to optimize the isolation success by selecting CB units of optimal quality. It is commonly agreed on that a high CB volume, a high cellular content, and a short time frame between birth and MSC isolation are criteria that will enhance the MSC isolation success.The procedures in this chapter are standardized protocols that were established and optimized in the authors' research laboratory; however, various modifications of the protocols are possible.