Potency of hair follicle bulb cells implanted into collagen/chitosan porous scaffolds to induce the growth of hair and formation of vessel-like structure in scaffolds / 中华皮肤科杂志

Objective To investigate the possibility of hair follicle reformation induced by hair follicle bulb cells implanted into collagen/chitosan porous scaffolds in vivo, and to observe the angiogenesis in implanted scaffolds.Methods Hair follicle bulb cells obtained by enzyme digestion from the hack skin of C57BL/6J mice were implanted into collagen/chitosan porous scaffolds followed by 2-week organotypie culture.Then,these collagen/chitosan porous scaffolds were transplanted subcutaneously into the dorsal skin of nude mice.Those nude mice transplanted with empty collagen/chitosan porous scaffolds served as the controls.The growth of hair was observed with naked eyes.Six weeks after the transplantation,skin samples were obtained from the recipient site and subjected to histological examination.Results Five weeks after the transplantation,hair growth was observed in the dorsal skin of nude mice.Six weeks later,histological examination revealed fully differentiated hair follicles and vessel-like structures in the center of collagen/chitosan porous scaffolds.However,the transplantation with empty collagen/chitosan porous scaffolds failed to elicit the same response.No hair or follicles were observed in the control mice alpng with small number of vessel-1ike structures.Con-clusions Hair follicle bulb ceils implanted into collagen/chitosan porous scaffolds in vivo could induce hair follicle reformation and promote the formation of vessel-like structure in the scafffold center.

Study on biologic characteristics of cultured dermal papilla cells and hair follicle regeneration in vitro and in vivo / 中华皮肤科杂志

Objective To observe the ability of cultured dermal papilla cells(DPCs) to induce hair follicle regeneration and to sustain hair growth in vivo and in vitro. Methods The expression of basic fibroblast growth factor (bFGF), endothelin-1 (ET-1) and stem cell factor (SCF) in different passages of DPCs, and their possible effects on biologic behaviour of DPCs were measured by in situ hybridization and immunohistochemistry. Hair follicle regeneration induced by DPCs in hair follicle organotypic culture model and the model implantated into nude mice were studied. Results The expression of ET-1 and SCF in the early passages of cultured DPCs was strong, but became weak and even negative after 6 passages. Hair follicle-like structures were formed in the hair follicle organotypic cultures, composed of DPCs and hair follicle epithelium cells. When the hair follicle organotypic cultures were implanted into the subcutis of nude mice, relatively intact hair follicles were formed. Injection of the early passage DPCs mixed with hair follicle epithelial cells into the subcutis of nude mice resulted in the formation of hair follicle-like structures, while the structures were not formed after the injection of the mixture of hair follicle epithelial cells with dermal sheath fibroblasts or with scalp fibroblasts. There was a positive correlation between the expression levels of ET-1 and SCF in DPCs and the ability of DPCs to induce hair follicle regeneration . Conclusions Cultured DPCs can induce hair follicle regeneration and sustain hair growth in vivo and in vitro. Moreover, the expression levels of ET-1 and SCF are positively correlated with the ability of DPCs to induce hair follicle regeneration.