抗菌肽LL-37、HBD-2和HBD-3在皮肤结核皮损中的表达

Expressions of LL-37, human beta defensin-2 and -3 in lesions of cutaneous tuberculosis

目的研究抗菌肽LL-37、人β防御素-2（HBD-2）、HBD-3在寻常狼疮和疣状皮肤结核皮损中的表达，探讨皮肤结核的发病机制。方法免疫组化方法检测LL-37、HBD-2、HBD-3在18例寻常狼疮和疣状皮肤结核患者皮损、15例银屑病患者皮损以及10例健康人皮肤石蜡切片中的表达。SPSS13．0统计软件进行数据分析，组间行t检验。结果LL-37、HBD-2在皮肤结核皮损中主要表达于表皮中上层、附属器及血管壁，与正常皮肤比较为高表达（t=2．632，2．399，P值均〈0．05），且与银屑病的表达模式类似。HBD-3在皮肤结核皮损中未见表达，而在银屑病皮损及正常皮肤中均可见表达。结论抗菌肽LL-37和HBD-2可能参与皮肤结核的免疫反应过程，而HBD-3在皮肤结核的表达缺失可能与其发病密切相关。

Objective To observe the expressions of antimicrobial peptides LL-37, human beta defensin- 2 （HBD-2） and HBD-3 in the lesions of lupus vulgaris and tuberculosis verrucosa cutis, and to speculate the pathogenesis of cutaneous tuberculosis. Methods Tissue specimens were collected from the lesions of 18 patients with lupus vulgaris or tuberculosis verrucosa cutis and 15 patients with psoriasis, as well as from the normal skin of 10 healthy controls. The specimens were embedded by paraffin and subjected to an immunohistochemical analysis for the detection of antimicrobial peptides LL-37, HBD-2 and HBD-3. Statistical analysis was performed by using the SPSS 13.0 software package, and t test was carried out to compare the expressions of LL-37, HBD-2 and HBD-3 between these groups. Results LL-37 and HBD-2 were observed mainly in the upper and middle layer of the epidermis, appendages and vascular endothelial cells in cutaneous tuberculosis lesions. The expression levels of LL-37 and HBD-2 were significantly higher in tuberculosis lesions than in the normal skin （t = 2.632, 2.399, both P 〈 0.05）. Psoriatic and tuberculosis lesions shared a similar expression pattern for LL-37 and HBD-2. HBD-3 was absent in the lesions of cutaneous tuberculosis, but present in both psoriatic lesions and normal skin. Conclusions Both LL-37 and HBD-2 may participate in the immune response in cutaneous tuberculosis, while the absence of HBD-3 may contribute to the pathogenesis of cutaneous tuberculosis.