Differentiation of human epidermal stem cells into fibroblasts induced by TGF-β1 in vitro

Abstract

Objective To investigate the correlation between human epidermal stem cell （hESCs） and hypertrophic scar or keloid. Methods Improved collagen Ⅳ-coated adhesion methods was used to isolate and culture the epidermal stem cells after neutral protease selectively digested the dermo-epidermal junctions. After the cells were cultured and expanded in vitro, and passage 3 hESCs were induced by different concentrations of TGF 131 （0.1, 5.0, and 10.0 ng/ml）. Morphological features and identification of these cells were meseasured by HE, Masson, immunohistochemical staining on the days 3 and 7, respectively. Results After induced by TGF-β1 for 3 and 7 days, the morphology of the epidermal stem cell （hESCs） was changed into fusiform shape, similar to fibroblasts. 70 % of the cell which was induced by TGF-β1 were blue stained in the cytoplasm by Masson stain, which is the distinctive method for collagen, suggesting collagen appeared or increased in the cells. The collagen concentrations in supernatants of hESCs were 0. 4150 ± 0. 0014, 0. 3380 ± 0. 0020, and 0. 3870± 0. 0020, much higher than that in control group （0. 0780 ± 0. 0025） and normal skin fibroblast group （0. 1500± 0. 0051）（P〈0. 05）. Immunohistochemical staining revealed that positive rates of these cells for anti-vimentin staining were more than （95.00± 1.20）% in experiments and （5. 70±0.20） % in control group. Conclusion The differentiantion of hESCs induced by TGF-β1 into fibroblasts indicates that hESCs may play a role in the pathogenesis of hypetrophic scar and keloid. Key words: Transforming growth factor β1 （ TGF 61）; Human epidermal stem cells; Fi broblast ; Differentiantion