PML蛋白表达在银屑病发病机制中的作用

目的　探讨早幼粒细胞白血病(PML)蛋白介导的细胞凋亡引发的免疫调节在银屑病发病机制中的作用及意义。方法　采用免疫组化方法和原位末端标记法研究银屑病患者不同期皮损中PML蛋白表达与细胞凋亡的关系。结果　银屑病患者进行期斑块型皮损中PML蛋白表达高于相邻非皮损区及恢复期皮损,正常表皮基本不表达;PML蛋白表达强的部位角质形成细胞凋亡明显。结论　PML蛋白表达增加所致的诱导凋亡增加可能是角质形成细胞过度增殖的自稳机制。

Role of promyelocytic leukemia protein expression in the pathogenesis of psoriasis

Objective To study the relationship between promyelocytic leukemia(PML) protein and apoptosis and their roles in the pathogenesis of psoriasis. Methods Immunohistochemical techniques were employed to study the expression of PML protein in the uninvolved skin, progressive plaque lesions and regressive lesions. Apoptosis was detected with terminal deoxynucleotidyl transferase-mediated dUTP-DIG nick end labeling(TUNEL). Results There was a significantly upregulated expression of PML protein in progressive plaque lesions, compared with that in uninvolved skin adjacent to the lesions and regressive lesions, and there was nearly no expression in normal skin; there was obvious apoptosis of keratinocytes in the epidermis with intensive PML protein staining. Conclusion The increased apoptosis of keratinocytes in the lesions of psoriasis induced by PML protein might be a homeostatic mechanism to the hyperplasia of keratinocytes.