二期梅毒皮疹中梅毒螺旋体基因检测和浸润细胞研究

目的：探讨二期梅毒皮疹的形成机制和细胞免疫在梅毒皮疹形成中的作用。方法：用巢式PCR方法对24例10％甲醛溶液固定、石蜡包埋的二期梅毒疹标本进行了梅毒螺旋体DNA检测；用免疫组化方法对二期梅毒皮损中的浸润细胞进行检测。结果：24份二期梅毒疹标本中10例(45．8％)检出了梅毒螺旋体DNA，所有标本银染色未发现苍白螺旋体(TP)。二期梅毒皮损浸润细胞中CD45RO( )T细胞100％阳性，68．2％有CD68( )巨噬细胞，此外还有少量CD20( )B淋巴细胞和CD57( )NK细胞。结论：二期梅毒疹的形成原因可能为螺旋体感染皮肤局部所致；二期梅毒疹皮损中浸润细胞主要为T淋巴细胞和巨噬细胞，细胞免疫在二期梅毒皮损发病中可能发挥重要作用。

Detection of treponema pallidum DNA in cutaneous lesions of secondary syphilis and characterization of the inflammatory infiltrate

Objective: To investigate the possible mechanism of the cutaneous lesion formation in secondary syphilis and role of cellular immunity in the pathogenesis of syphilis. Methods: Treponema pallidum DNA was detected in 24 formalin fixed, paraffin embedded skin specimens from lesions of secondary syphilis by nested PCR. The inflammatory infiltrate in the cutaneous lesions of secondary syphilis was investigated using immunohistochemical technique. Results: The TP specific DNA was found in 10 of 24 (45.8%) lesions of secondary syphilis. However, no Treponema pallidum were found in all 24 tissue section samples when silver staining was performed. CD45RO (+) Tcells were found in all syphilis lesions with strong staining. CD68 (+) cells were found in 68.2% of the skin specimens. Meanwhile,a few CD20 (+) cells and CD57 (+) cells were seen in the infiltrates. Conclusion: The cutaneous lesions might be formed by invasion of TP to skin rather than an allergic reaction. The predominant T cells and macrophages infiltrating in secondary syphilitic lesions indicate that cellular immunity might play a critical role in host reaction against TP infection.