糖皮质激素受体-α、核因子-κB、肿瘤坏死因子-α和白介素-1β在慢性皮炎中的表达

Expression of GR-α, NF-κB, TNF-α and IL-1β in chronic dermatitis

目的:探讨糖皮质激素受体(glucocorticoidreceptor,GR)-α、核因子(NF)-κB、肿瘤坏死因子(TNF)-α和白介素(IL)-1β在慢性皮炎中的表达及其意义。方法:采用SP免疫组化染色技术检测慢性皮炎与正常对照皮肤中GR-α、NF-κB、TNF-α及IL-1β的表达及其分布。结果:GR-α在慢性皮炎组与正常对照组皮肤中阳性表达的分布情况一致,GR-α不但在表皮呈弥漫性表达,还可表达于汗腺及汗管、真皮成纤维细胞、微血管内皮细胞及其周围的一些细胞成分。然而,与正常对照皮肤相比,GR-α在慢性皮炎皮损角质形成细胞及真皮血管内皮细胞的表达明显减弱。NF-κB在慢性皮炎组与正常对照组皮肤中阳性表达主要分布在表皮角质形成细胞中,在正常对照组皮肤中均为胞质表达,而在慢性皮炎组中为胞质表达和(或)胞核均有表达。TNF-α及IL-1β在慢性皮炎与正常对照皮肤角质形成细胞胞质中的表达无明显差异,为弱阳性反应。结论:慢性皮炎皮损区角质形成细胞中GR-α的表达下调有可能会影响皮损局部的抗炎机制。

Objective： To investigate the expression and significance of glucocorticoid receptor （GR）-α, NF-kB, TNF-α and IL-1β in chronic dermatitis. Methods： Streptavidin/peroxidase（SP）immunohistochemical technique was employed to examine the expression and distribution of GR-α, NF-KB, TNF-α and IL-1β in chronic dermatitis and normal skin. Results： The distribution of GR-α in chronic dermatitis and normal skin is similar. The positive staining of GR-α was localized in the epidermis, eccrine gland and its duct, dermal fibroblasts, microvascular endothelial cells, and some cells around microvessels. In comparison with the normal skin, GR-α expression of keratinocytes in epidermis and microvascular endothelial cells in upper dermis was down-regulated in chronic dermatitis. NF-kB was not only expressed in the cytoplasm of keratinocytes in normal skin and chronic dermatitis, but also in the nuclei of keratinocytes in chronic dermatitis. The expression of TNF-α and IL-1β was weakly positive in both chronic dermatitis and normal skin. Conclusion： Down-regulated GR-α expression of keratinocytes and microvascular endothelial cells in chronic dermatitis may influence anti-inflammatory mechanism in the lesions.