肌成纤维细胞在皮肤瘢痕形成过程中的作用

目的 探讨表达α平滑肌肌动蛋白(α-smooth muscle actin,α-SMA)的肌成纤维细胞在皮肤增牛性瘢痕中的作用.方法 免疫组织化学法检测皮肤增牛性瘢痕中α-SMA的表达;通过细胞培养,检测成纤维细胞与肌成纤维细胞羟脯氨酸含量并进行比较;ELISA法分别检测成纤维细胞与肌成纤维细胞Ⅲ型前胶原、纤维连接蛋白、TGF-β1含量并进行比较.结果 正常皮肤组织只有血管平滑肌细胞表达α-SMA,其他真皮细胞几乎不表达,增生性瘢痕皮肤组织中,α-SMA染色阳性细胞大大增加,比例高达96.89%,两者比较,差异有统计学意义(P<0.01);肌成纤维细胞羟脯氨酸含量较正常成纤维细胞显著增高(P<0.01);肌成纤维细胞Ⅲ型前胶原含量较成纤维细胞显著增高(P<0.05);肌成纤维细胞TGF-β1含量较正常成纤维细胞显著增高(P<0.01);肌成纤维细胞纤维连接蛋白含量较成纤维细胞显著增高(P<0.05).结论 肌成纤维细胞是造成增生性瘢痕的最关键细胞.

Role of myofibroblasts in formation of hypertrophic scar

Objective To explore the role of myofibroblasts expressing α-smooth muscle actin (a-SMA) in hyperplastic scar formation.Methods Expression of α-SMA in normal skin and scar was examined by means of immunohistochemistry.The contents of myofibroblasts were measured and com-pared with that of hydroxyproline through cell culture.The contents of precollagen (pc β) , transforming growth factor β (TGF-β) and fibronectin in fibroblasts and myofibroblasts were assayed by ELISA.Results Vascular smooth muscle cells rather than other hypodermal cells expressed α-SMA in normal skin (P<0.01).The expression ofa-SMA was markedly increased up to 96.89% in hyperplastic scar tissues, with statistical difference compared with normal skin (P < 0.01).The contents of hydroxyproline (P <0.01) , pc (P <0.05) , TGF-β (P <0.01) and fibronectin (P <0.05) in myofibroblasts were significantly higher than those in fibroblasts.Conclusion Myofibroblasts play a key role in formation of hypertrophic scar.