Objective To review the research progress of hair follicle stem cell(FSC) in wound healing and correlative signals. Methods The advances in the FSC location, characters, relations with wound repair and correlative singals were introduced based on the recent related literature. Results FSC played an important role in hair follicle cycle and wound healing. The correlative signals maybe Wnt, bone morphogenetic protein/transforming growth factor β, Norch, Shh and fibroblast growth factor. Conclusion The multipotency and plasticity of FSC offer a new way in regeneration medicine and the signals in cell proliferation and differentiation will be the new focus in future research.
Objective To establish a method of constructing skin-equivalents (SE) by the hair follicle stem cells (HFSC) and the fibroblasts. Methods The K19 immunostainning was employed to localize the HFSC in the human scalp from the cosmetic surgery. The isolated HFSC through the enzyme digestion were seeded on the dermal equivalent (DE) formed by polymerization of the fibroblasts and collagen. After being cultured between the air-liquid interface for 14 days, SE were harvested and used for an evaluation. Results HFSC were located mainly in the outer root sheath in the hair follicle. Based on DE, the growing HFSC could build a fullydeveloped and multilayered epidermis with the basal membrane formedb etween the epidermis and the dermis. The fibroblasts were active and spread evenly in the collagen matrix. Conclusion The hair follicle stem cells located in the outer root sheath can be successfully used to construct skin-equivalents in vitro and have a promising clinical use in the treatment.
Objective To investigate the possibility of hair follicle reformation induced by dermal papilla cells in vivo and in vitro. Methods Dermal papilla cells, dermal sheath fibroblasts obtained by enzyme digestion were mixed with collagen to form mesenchymal cell populationed collagen gel. Superior and inferior epithelial cells and bulb matrical cells then were cultured on these gel as organotypic culture to recombine bilayer artificial skin. Dermal papilla cells and outer root sheath keratinocytes were mingled and transplanted under subcutaneous tissue of the dorsal skin of nude mice. Hair follicle formation was observed by histological examination. Results These recombinants all reformed bilayer structure like nature skin.Hair follicle reformation was found in dermal sheath fibroblast-populationed collagen gel combined with superior and inferior epithelial cells. Dermal papilla cells also induced superior and inferior epithelial cells to from hair follicle on nude mice. Lowe passage dermal papilla cells mixed with hair follicle epithelial cells formed many trpical hair follicle structures and produced hair fiber after transplanted on nude mice. Conclusion The dermal part of hair follicle, such as dermal papilla cells and dermal sheath fibroblsast, have the ability to induce hair follicel formation by interaction between the epithelial cells of hair follicle.
ObjectiveTo obtain rat hair follicle stem cells (rHFSCs) which can constantly and highly express vascular endothelial growth factor 165 (VEGF165), and to observe the expression of VEGF165 gene in rat HFSCs. MethodsThe cirri skin of 1-week-old Sprague Dawley rat was harvested and digested by using combination of Dispase and type IV collagenases. The bulge was isolated under microscope. The rHFSCs were cultured by tissue block method. After purified by rapid adhering on collagen type IV, the growth curve of different generations rHFSCs was drawn. The cells were identified by immunofluorescence staining and real time quantitative PCR (RT-qPCR) analysis that tested the expression level of correlated genes. Lentivirus of pLV-internal ribosome entry site (IRES)-VEGF165-enhanced green fluorescent protein (EGFP) (experimental group) and pLV-IRES-EGFP empty vector (control group) was packaged by calcium transfected method and the rHFSCs were transfected. The green fluorescent protein expression was observed by inverted fluorescence microscope, and VEGF165 mRNA and protein expressions were detected using RT-PCR and Western blot. ResultsThe rHFSCs which were isolated, cultured, and purified were like the "slabstone", and had strong adhesion ability and colony formation ability. The purified cells were in latent growth phase at 2-3 days; they were in exponential growth phase at 5-6 days. The expressions of cytokeration 15 (CK15), integrin α6, and integrin β1 (markers of HFSCs) were positive by immunocytochemistry. The RT-qPCR analysis showed that CK15, CK19, integrin α6, and integrin β1 expressed highly, but CD34 (a marker of epidermal stem cells) and CK10 (a marker of keratinocyte) expressed lowly. After 14 days, the transfection efficiency was up to 85.76%±1.91%. RT-PCR analysis and Western blot showed that VEGF165 mRNA and protein expressions were positive in experimental group, and were negative in control group. ConclusionThe rHFSCs with high purity and strong proliferation ability can be obtained by using microscope combined with tissue cultivation and rapid cell adhesion on collagen type IV. The rHFSCs with high expression of VEGF165 can be successfully obtained by lentiviral transfection. This method provides good seeding cells for tissue engineering to construct artificial hair follicles, blood vessels, and skins.
ObjectiveTo investigate the co-transplantation of C57-green fluorescent protein (GFP) mouse epidermis and dermis cells subcutaneously to induce the hair follicle regeneration. MethodC57-GFP mouse epidermis and dermis were harvested for isolation the mouse epidermis and dermis cells. The morphology of epidermis and dermis mixed cells at ratio of 1:1 of adult mouse, dermis cells of adult mouse, cultured 3rd generation dermis cells were observed by fluorescence microscope. Immunocytochemistry staining was used to detect hair follicle stem cells markers in cultured 3rd generation dermis cells from new born C57-GFP mouse. And then the epidermis and dermis mixed cells of adult mouse (group A), dermis cells of adult mouse (group B), cultured 3rd generation dermis cells of new born mouse (group C), and saline (group D) were transplanted subcutaneously into Balb/c nude mice. The skin surface of nude mice were observed at 4, 5, 6 weeks of transplantation and hair follicle formation were detected at 6 weeks by immunohistochemistry staining. ResultsThe isolated C57-GFP mouse epidermis and dermis cells strongly expressed the GFP under the fluorescence microscope. Immunocytochemistry staining for hair follicle stem cells markers in cultured 3rd generation dermis cells showed strong expression of Vimentin and α-smooth muscle actin, indicating that the cells were dermal sheath cells; some cells expressed CD133, Versican, and cytokeratin 15. After transplanted for 4-6 weeks, the skin became black at the injection site in group A, indicating new hair follicle formation. However, no color change was observed in groups B, C, and D. Immunohistochemical staining showed that new complete hair follicles structures formed in group A. GFP expression could be only observed in the hair follicle dermal sheath and outer root sheath in group B, and it could also be observed in the hair follicle dermal sheath, outer root sheath, dermal papilla cells, and sweat gland in group C. The expression of GFP was negative in group D. ConclusionsCo-transplantation of mouse epidermis and dermis cells can induce the hair follicle regeneration by means of interaction of each other. And transplantation of isolated dermis cells or cultured dermis cells individually only partly involved in the hair follicles formation.
ObjectiveTo explore the research progress of hair follicle and related stem cells in scar-free skin healing in recent years.MethodsThe literature related to hair follicle and related stem cells, wound healing, and scar formation in recent years was extensively reviewed and summarized from the aspects of cell function and molecular mechanism.ResultsScar tissue after wound healing treated with hair follicle transplantation and related stem cell therapy is more mild or even without scar formation. The cell types and molecular mechanisms of the above phenomena are complex, and the bone morphogenetic protein signal transduction pathway and Wnt signal transduction pathway are strongly correlated.ConclusionThe research of hair follicle and related stem cells in scar-free skin healing is at the initial stage at present. Strengthening the mechanism research may provide new ideas for the treatment of wound and scar.