Ballot E, Desbos A, Auger C, Monier J C
Laboratoire d'Immunologie, Faculté de Médecine Alexis Carrel, Lyon, France.
Clin Immunol Immunopathol. 1996 Sep;80(3 Pt 1):255-65. doi: 10.1006/clin.1996.0121.
Previous studies have demonstrated that sera from patients with autoimmune hepatitis type 1 contain antibodies which react with proteins other than the endoplasmic reticulum integral membrane protein of apparent Mr 50,000, now known to be a cytochrome P450 of the IID subfamily. Sera from 141 patients found by immunofluorescence to be positive for anti-liver-kidney microsome antibodies type 1, and sera from 50 blood donors used as controls, were analyzed by immunoblotting experiments on rat liver microsomes, microsomal subfractions, and also microsomes subjected to various treatments, as described in the text. These fractions were characterized morphologically by electronic microscopy and biochemically by different enzymatic activities. Five bands were found to be stained more often by the patients' sera than by the controls' and with a statistically significant difference in frequency. These antigenic proteins were located at apparent Mr 62,000, 58,000, 50,000, 40,000, and 35,000. The 50,000 protein was of course more often stained than the others. Antibodies against these antigens belonged essentially to the IgG1 subclass. For some of them, subcellular localization and membrane topography are discussed. Interestingly, the 58,000 protein is not an integral membrane protein.
先前的研究表明，1型自身免疫性肝炎患者的血清中含有与除表观分子量为50,000的内质网整合膜蛋白以外的蛋白质发生反应的抗体，该蛋白现在已知是IID亚家族的一种细胞色素P450。如文中所述，对141例经免疫荧光检测抗1型肝肾微粒体抗体呈阳性的患者血清以及50例作为对照的献血者血清，采用大鼠肝微粒体、微粒体亚组分以及经过各种处理的微粒体进行免疫印迹实验分析。这些组分通过电子显微镜进行形态学表征，并通过不同的酶活性进行生化表征。发现有五条带被患者血清染色的频率高于对照血清，且频率差异具有统计学意义。这些抗原蛋白的表观分子量分别为62,000、58,000、50,000、40,000和35,000。当然，分子量为50,000的蛋白被染色的频率比其他蛋白更高。针对这些抗原的抗体主要属于IgG1亚类。文中对其中一些抗原的亚细胞定位和膜拓扑结构进行了讨论。有趣的是，分子量为58,000的蛋白不是整合膜蛋白。
