副肿瘤性天疱疮自身抗原表位研究

Autoantigen epitopes in paraneoplastic pemphigus

目的探讨副肿瘤性天疱疮的自身抗原表位。方法运用重组融合蛋白免疫印迹实验、合成短肽酶联免疫吸附实验、竞争性酶联免疫吸附实验和斑点免疫印迹实验对副肿瘤性天疱疮的主要自身抗原-斑蛋白家族分子进行研究。结果斑蛋白家族中周斑蛋白和包斑蛋白的L亚区是副肿瘤性天疱疮患者血清识别的主要抗原，其中包斑蛋白L亚区第1738～1757位氨基酸序列中存在着特异性抗原表位，可被多数副肿瘤性天疱疮血清识别。结论包斑蛋白L亚区中存在着副肿瘤性天疱疮的特异性抗原表位。

Objective To investigate the autoantigen epitopes in paraneoplastic pemphigus （PNP）. Methods Serum samples were collected from 12 patients with PNP, 12 with pemphigus vulgaris, 12 with pemphigus foliaceus, 12 with bullous pemphigus and 20 normal controls. Immunoblotting was performed using recombinant fused proteins including envoplakin, periplakin, desmoplakin and BPAG1. Twelve peptides covering the linker subdomain of envoplakin were synthesized for ELISA and dot blotting to delineate the epitopes in this region. Results The recombinant linker subdomains of envoplakin, periplakin, desmoplakin and BPAG1 were recognized by 11, 11, 7 and 9 of the 12 sera from PNP patients, respectively. As shown by ELISA, all the 12 peptides demonstrated different specificity and affinity to PNP sera,and most of the results were consistent between dot blotting and ELISA. There were specific antigen epitopes in the linker subdomain of envoplakin from site 1738 to 1757, which could be recognized by the sera from PNP patients. Conclusion Specific antigen epitopes of PNP are present in the linker subdomain of envoplakin.