白癜风皮损黑素细胞HMB-45、酪氨酸酶及其相关蛋白1的免疫组化研究

目的:研究白癜风白斑处黑素细胞分布及酪氨酸酶(TYR)等标记分子的表达情况。方法:对吸疱法所取白斑皮肤以免疫组化染色识别TYR、酪氨酸酶相关蛋白1(TRP1)和HMB-45,以Mias99彩色图像分析软件定量图像分析阳性表达的强弱。结果:白斑处黑素细胞数目明显低于正常对照(P<0.01),患者非皮损处与正常人皮肤比较差异无显著性(P>0.05)。皮损处黑素细胞树突减少,平均为3.4个,低于对照组(P<0.05)。残留黑素细胞各抗体呈强阳性染色。白斑毛囊之间可见黑素细胞散在、呈围管样分布。白斑处阳性细胞HMB-45图像灰度值低于正常着色皮肤(P<0.05),而TRP1高于正常皮肤(P<0.01),TYR与正常皮肤无差异(P>0.05)。结论:白斑处仍然有黑素细胞。残存黑素细胞树突回缩、数目变少,而且黑素细胞中黑素细胞标记分子表达异常。

Immunohistochemical study on HMB-45, tyrosinase and TRP1 in the residual melanocytes of vitiligo

Objective: To investigate morphological changes and expressions of HMB-45, tyrosinase(TYR) and tyrosinase related protein1(TRP1) on the melanocytes of vitiligo. Methods: A panel of antibodies recognizing specific markers of the melanocytes were used to stain epidermal sheet immunohistochemically. Expressions of those different molecules of melanocytes were analyzed quantitively with image analysis system. Results: HMB-45 positive melanocytes were reduced significantly at the epidermal sheets of the lesions (P < 0.05). Dendrites of the residual melanocytes were reduced with an average number of 3.4, which is below the control level. Residual melanocytes were stained positively with those antibodies. Occasionally, hair follicles were surrounded by tripolar or polygonal melanocytes in a diffuse or concentric pattern. Melanocytes in the lesions expressed the lower density of antigen that can be recognized by HMB-45 antibody compared to the control(P < 0.05) and opposite result was obtained for TRP1 (P < 0.01). Conclusions: Melanocytes still exist in the lesions of vitiligo, characterized with retractions of their dendrites and abnormal expression of different molecules.