培养毛乳头细胞生物学特性和毛囊重建的研究

Study on biologic characteristics of cultured dermal papilla cells and hair follicle regeneration in vitro and in vivo

目的观察毛乳头细胞在体内外诱导毛囊再生和支持毛囊生长情况。方法采用免疫组化、原位杂交、毛囊器官型培养和裸鼠移植技术,观察不同传代培养的毛乳头细胞碱性成纤维细胞生长因子,内皮素和干细胞因子的表达变化情况。结果低传代培养的毛乳头细胞的内皮素和干细胞因子表达较强,传代6代后减弱。用低传代培养的毛乳头细胞与毛囊上皮细胞在毛囊器官型培养模型中可见毛囊样结构形成,移植到裸鼠后可见较为完整的毛囊形成。用低传代培养的毛乳头细胞与毛囊上皮细胞按一定比例混合后直接注射到裸鼠皮下,也可见毛囊样结构形成。发现毛乳头细胞诱导毛囊再生的能力与其表达内皮素和干细胞因子的强弱相关。结论低传代培养的毛乳头细胞在体内外均具有诱导毛囊再生的能力,并且与其表达内皮素和干细胞因子的强弱相关。

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 ofDPCs to induce hair follicle regeneration. Conelusions CulturedDPCs 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.