扁平苔藓皮损中肿瘤坏死因子α和半胱氨酸天冬氨酸蛋白酶8、3的表达

Expressions of tumor necrosis factor-α, caspase-8 and caspase-3 in lichen planus lesions

目的研究扁平苔藓皮损中肿瘤坏死因子α（TNF—α）、半胱氨酸天冬氨酸蛋白酶8（Caspase-8）和Caspase-3的表达及意义。方法采用免疫组化法和原位末端标记技术（TUNEL）检测20例扁平苔藓患者皮损和20例健康人皮肤组织中TNF—α、Caspase-8、Caspase-3的表达和细胞凋亡情况。采用SPSS11．5统计软件，组间比较采用成组t检验，指标间相关性采用Pearson相关分析。结果扁平苔藓组TNF—α、Caspase-8和Caspase-3的积分光密度值分别为12580±2330、11690±3520和11450±2820，均明显高于健康对照组（分别为5120±1780、3870±3360、4760±1930），两组比较，t值分别为11．38、7．19、8．76，P值均〈0．01；扁平苔藓组角质形成细胞凋亡指数（71．35±7．93），明显高于健康对照组（33．62±8．75），两组比较，t=14．29，P〈0．01。扁平苔藓组TNF-仪、Caspase-8的表达强度与角质形成细胞凋亡指数间均呈正相关，r分别为0．72、0．75，P值均〈0．01；同时两者与Caspase-3的阳性表达也均呈正相关，f分别为0．68、0．73，P值均〈0．01。结论TNF—α、Caspase-8和Caspase-3的高表达可能参与了扁平苔藓中角质形成细胞的凋亡。

Objective To quantify the expressions of tumor necrosis factor-α （TNF-α）, caspase-8 and caspase-3 in lichen planus （LP） lesions, and to investigate their significance. Methods Skin samples were collected from the lesions of 20 patients with LP and normal skin of 20 healthy human controls. Immunohistochemistry was used to determine the expressions of TNF-α, caspase-8 and caspase-3, and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labeling （TUNEL） technique to evaluate the apoptosis in keratinocytes, in these samples. Results The expression levels （expressed in integrated optical density, IOD） of TNF-α, caspase-8 and caspase-3 were （12.58 ± 2.33） 10^3, （11.69± 3.52） x 10^3 and （11.45 ± 2.82） x 103 respectively in LP lesions, significantly higher than those in the normal skin （（5.12 ± 1.78） x 10^3, （3.87± 3.36） x 10^3, （4.76 ± 1.93） x 10^3, t = 11.38, 7.19, 8.76,respectively, all P 〈 0.01 ）. Elevated apoptosis index was noted in keratinocytes from LP lesions compared with those from normal skin （71.35 ± 7.93 vs. 33.62±8.75, t = 14.29, P 〈 0.01 ）. In LP lesions, the expressions of both TNF-α and easpase-8 were positively correlated with the apoptosis index of keratinocytes （r = 0.72, 0.75, respectively, both P 〈 0.01） and the expression of easpase-3 （r = 0.68, 0.73, respectively, both P 〈 0.01）. Conclusion The up-regulated expressions of TNF-α, caspase-8 and easpase-3 may participate in the apoptosis in keratinoeytes in LP.