Bernard P, Prost C, Durepaire N, Basset-Seguin N, Didierjean L, Saurat J H
Department of Dermatology, University Canton-Hospital, Genève, Switzerland.
J Invest Dermatol. 1992 Aug;99(2):174-9. doi: 10.1111/1523-1747.ep12616797.
Recent studies have shown that sera from patients with cicatricial pemphigoid (CP) contained autoantibodies against epidermal antigens of molecular weight 230 kD and/or 180 kD by immunoblotting, similar to those recognized by bullous pemphigoid (BP) sera. Previous immunoprecipitation studies have shown that BP sera only precipitated the 230-kD antigen. To characterize the CP antigen(s) we tested 10 CP sera, 10 BP sera, and four controls by both immunoprecipitation of radiolabeled cells and immunoblotting of epidermal extracts. For immunoprecipitation, we used 0.5% NP-40 extracts of both normal human keratinocytes and Pam cells. All CP sera precipitated a 180-kD protein that co-migrated with the BP180 antigen precipitated by some individual BP sera. Two of these CP sera also faintly bound a 230-kD protein of similar molecular weight as the major BP230 antigen. CP and BP sera with an immunoblotting pattern of 180 kD immunoprecipitated a co-migrating 180-kD protein. CP sera reacting by immunoblotting with the 230-kD antigen precipitated the 180-kD and/or the 230-kD antigen. In contrast, BP sera reacting with the 230-kD antigen only precipitated this antigen. In further experiments, labeled 0.5% NP-40 extracts from Pam cells were first preabsorbed with a reference BP serum and then immunoprecipitated with CP sera. Under these conditions, CP sera that immunoprecipitated both 180-kD and 230-kD proteins with the standard procedure no longer precipitated these proteins. Our results suggest that a 180-kD protein is the major CP target-antigen that demonstrated immunologic cross-reactivities with the BP180 and the BP230 antigens.
近期研究表明，通过免疫印迹法检测，瘢痕性类天疱疮（CP）患者血清中含有针对分子量为230 kD和/或180 kD的表皮抗原的自身抗体，这与大疱性类天疱疮（BP）血清识别的抗原相似。先前的免疫沉淀研究表明，BP血清仅沉淀230-kD抗原。为了鉴定CP抗原，我们通过对放射性标记细胞进行免疫沉淀以及对表皮提取物进行免疫印迹，检测了10份CP血清、10份BP血清和4份对照血清。对于免疫沉淀，我们使用了正常人角质形成细胞和Pam细胞的0.5%NP-40提取物。所有CP血清均沉淀出一种180-kD蛋白，该蛋白与一些个体BP血清沉淀出的BP180抗原共迁移。其中两份CP血清还微弱结合了一种分子量与主要BP230抗原相似的230-kD蛋白。具有180 kD免疫印迹模式的CP和BP血清沉淀出一种共迁移的180-kD蛋白。通过免疫印迹与230-kD抗原发生反应的CP血清沉淀出180-kD和/或230-kD抗原。相比之下，与230-kD抗原发生反应的BP血清仅沉淀该抗原。在进一步的实验中，先用参考BP血清预吸收Pam细胞的标记0.5%NP-40提取物，然后用CP血清进行免疫沉淀。在这些条件下，用标准程序同时沉淀180-kD和230-kD蛋白的CP血清不再沉淀这些蛋白。我们的结果表明，一种180-kD蛋白是主要的CP靶抗原，它与BP180和BP230抗原表现出免疫交叉反应性。
