Anti-laminin gamma-1 pemphigoid
Anti-laminin gamma-1 pemphigoid
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DOI：
10.1073/pnas.0809230106
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发表时间：
2009-02-24
影响因子：
11.1
通讯作者：
Hashimoto, Takashi
中科院分区：
文献类型：
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作者：
Dainichi, Teruki;Kurono, Sadamu;Hashimoto, Takashi
抗P200类天疱疮的特征是对真皮-表皮交界处一种未知的200 kDa蛋白(P200)产生自身抗体。本研究的目的是确定P200。我们对患者的血清进行了真皮提取物的2D凝胶电泳和免疫印迹，然后对一条独特的蛋白条带进行了MS分析。免疫印迹显示抗层粘连蛋白γ1单抗与抗P200免疫沉淀物发生免疫反应。32例抗P200类天疱疮患者血清对层粘连蛋白γ1重组产物的反应率为90%。健康对照血清均未与层粘连蛋白γ1反应。通过免疫印迹法，加入抗层粘连蛋白γ1 C末端单抗可竞争性抑制患者血清与P200的反应。纯化的抗P200抗体也抑制了该单抗与真皮层粘连蛋白-γ1的反应。大多数层粘连蛋白-γ-1阳性血清与重组层粘连蛋白-γ1 C端E8片段具有反应活性。在还原条件下，患者血清和纯化的免疫球蛋白对真皮层粘连蛋白-1的反应性高于对血管层粘连蛋白-γ-1的反应性。这些结果表明，层粘连蛋白-γ1是抗P200类天疱疮患者的自身抗原。自身抗体可以通过独特的翻译后修饰来特异性识别真皮层粘连蛋白伽马1。该表位定位于卷曲结构域中的246C-末端氨基酸。已知的9个C末端残基与整合素的层粘连蛋白识别密切相关。
Anti-p200 pemphigoid has been characterized by autoantibodies to an unidentified 200-kDa protein (p200) of the dermal-epidermal junction. The objective of this study was to identify p200. We performed 2D gel electrophoresis of dermal extracts and immunoblotting with patients' sera, followed by MS analysis of a unique protein band. The protein band corresponded to laminin gamma 1. Anti-laminin gamma 1 mAb reacted with the anti-p200 immunoprecipitates by immunoblotting. Sera from 32 patients with anti-p200 pemphigoid showed 90% reactivity to the recombinant products of laminin gamma 1. None of the healthy control sera reacted with laminin gamma 1. By immunoblotting, reactivity of a patient's serum with p200 was competitively inhibited by adding anti-laminin gamma 1 C-terminus mAb. Purified anti-p200 IgG also inhibited the reactivity of this mAb to dermal laminin gamma 1. Most laminin gamma 1-positive sera showed reactivity with recombinant laminin gamma 1 C-terminal E8 fragment. Reactivity of patients' sera and purified IgG to dermal laminin gamma 1 was higher than reactivity to blood vessel laminin gamma 1 under reducing conditions. These results suggest that laminin gamma 1 is the autoantigen for patients with anti-p200 pemphigoid. The autoantibodies may specifically recognize dermal laminin gamma 1 with unique posttranslational modifications. The epitope is localized to the 246 C-terminal amino acids within the coiled-coil domain. The 9 C-terminal residues are known to be critically involved in laminin recognition by integrins.