黄芪诱导表皮干细胞增殖构建组织工程皮肤治疗皮肤缺损

Construction and application for skin defect repair of tissue engineered skin with human epidermal stem cells induced by Radix Astragalis

目的 :观察黄芪对人表皮干细胞增殖的影响 ,并探讨采用表皮干细胞构建组织工程皮肤用于皮肤缺损修复治疗的可能性。方法 :利用胶原快速贴附法分离纯化人表皮干细胞 ,以含黄芪、成纤维细胞条件培养液的表皮干细胞培养液进行体外培养 ,通过 β1整合素和角蛋白 19免疫组化染色、细胞克隆形成率测定 ,对培养细胞进行鉴定 ;并将表皮干细胞与真皮支架材料复合构建组织工程复合皮肤 ,移植于兔耳全层皮肤缺损创面 ,观察创面愈合情况及毛囊的组织学变化。结果 :人表皮干细胞表达 β1整合素和角蛋白 19,呈明显克隆性生长 ,其克隆形成率明显高于角质细胞对照组 ;兔耳创面愈合后 8周可见新生毛囊形成。结论 :在本实验条件下 ,黄芪能诱导表皮干细胞增殖 ,表皮干细胞可参与创面新生毛囊结构的形成 。

Objective: To investigate the effect of Radix Astragalis on the proliferation of human epidermal stem cells and the feasibility of tissue engineered skin prepared by epidermal stem cells graft onto the full skin loss wounds. Methods: The human epidermal stem cells were isolated by means of collagen rapid adhering method and cultured in vitro using epidermal stem cell medium contained Radix Astragalis and fibroblast conditioned medium. The cultured cells were identified by immunohistochemistry staining of β1 integrin and keratin 19, clone forming efficiency determination. The tissue engineered skin was constructed by combining epidermal stem cells with dermal scaffold materials and grafted onto full skin loss wounds on the ears of rabbit. Wound healing and histological changes of the hair follicles were observed. Results: There were positive expressions of β1 integrin and keratin 19 in human epidermal stem cells. Cultured human epidermalstem cells formed large clones, and in which clone forming efficiency was much higher than that in keratinocytes control group. The fresh forming hair follicle could be found 8 weeks after the wound healing in the grafting place. Conclusion: Human epidermal stem cells could be proliferated effectively under the induction of Radix Astragalis and might participate in the forming of hair follicle. These results suggest that the epidermal stem cells maybe unfold the potential applied prospects for construction and application of tissue engineered skin.