Tight clustering of extracellular BP180 epitopes recognized by bullous pemphigoid autoantibodies.
Tight clustering of extracellular BP180 epitopes recognized by bullous pemphigoid autoantibodies.
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DOI：
10.1111/1523-1747.ep12337492
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发表时间：
1997-10
期刊：
影响因子：
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通讯作者：
D. Zillikens;Pamela A. Rose;S. D. Balding;Zhi Liu;M. Olague-Marchan;L. Diaz;G. Giudice
中科院分区：
文献类型：
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作者：
D. Zillikens;Pamela A. Rose;S. D. Balding;Zhi Liu;M. Olague-Marchan;L. Diaz;G. Giudice
大疱性类天疱疮是一种与抗BP 180抗原（半桥粒的跨膜成分）的自身抗体相关的起泡性皮肤病。抗BP 180抗体已被证明在被动转移小鼠模型中是致病性的。人BP 180（MCW-1）上的一个细胞外位点先前显示被50-60%的大疱性类天疱疮血清识别。为了便于鉴定额外的自身抗体反应性表位，使用细菌和哺乳动物表达系统产生BP 180胞外域的重组形式。在COS-1细胞中表达的一种重组蛋白sec 180 e，含有完整的BP 180胞外域，为我们提供了一种检测构象表位的工具。大疱性类天疱疮血清免疫吸附的主要noncollagenous NC 16 A域不再与sec 180 e反应，表明自身抗体反应性的BP 180胞外域是有限的NC 16 A区域。用一系列重组NC 16 A肽免疫吸附的大疱性类天疱疮血清的免疫印迹分析揭示了三个新的自身抗原位点的存在，这些位点沿着MCW-1表位聚集在NC 16 A的N-末端45个氨基酸延伸内。所有15个大疱性类天疱疮血清测试与含有此BP 180片段的重组蛋白反应。在NC 16 A的剩余28个氨基酸内未检测到疾病相关表位。因此，大疱性类天疱疮患者自身抗体与高度成簇的BP 180胞外域上的一组表位反应。人BP 180上的该自身抗体反应性区域显示与相应的鼠BP 180位点重叠，所述鼠BP 180位点被大疱性类天疱疮小鼠模型中的致病抗体靶向。这些发现为开发这种疾病的诊断和治疗工具提供了新的方向。
Bullous pemphigoid is a blistering skin disease associated with autoantibodies against the BP180 antigen, a transmembrane component of the hemidesmosome. Anti-BP180 antibodies have been demonstrated to be pathogenic in a passive transfer mouse model. One extracellular site on human BP180 (MCW-1) was previously shown to be recognized by 50-60% of bullous pemphigoid sera. To facilitate the identification of additional autoantibody-reactive epitopes, recombinant forms of the BP180 ectodomain were generated using both bacterial and mammalian expression systems. One recombinant protein, sec180e, that was expressed in COS-1 cells and that contained the entire BP180 ectodomain, provided us with a tool to detect conformational epitopes. Bullous pemphigoid sera immunoadsorbed against the major noncollagenous NC16A domain no longer reacted with sec180e, indicating that autoantibody reactivity to the BP180 ectodomain is restricted to the NC16A region. Immunoblot analysis of bullous pemphigoid sera immunoadsorbed with a series of recombinant NC16A peptides revealed the presence of three novel autoantigenic sites that, along with the MCW-1 epitope, are clustered within the N-terminal 45 amino acid stretch of NC16A. All 15 bullous pemphigoid sera tested reacted with a recombinant protein containing this BP180 segment. No disease-associated epitopes were detectable within the remaining 28 amino acids of NC16A. Thus, bullous pemphigoid patient autoantibodies react with a set of epitopes on the BP180 ectodomain that are highly clustered. This autoantibody-reactive region on human BP180 shows overlap with the corresponding murine BP180 site that is targeted by antibodies that are pathogenic in the mouse model of bullous pemphigoid. These findings suggest new directions for the development of diagnostic and therapeutic tools for this disease.