Gueguen M, Meunier-Rotival M, Bernard O, Alvarez F
Institut National de la Sante et de la Recherche Medicale (INSERM U 56), Bicêtre, France.
J Exp Med. 1988 Aug 1;168(2):801-6. doi: 10.1084/jem.168.2.801.
Children with autoimmune hepatitis have high serum titers of antibodies directed against a 50-kD protein of rat liver endoplasmic reticulum. Affinity-purified anti-50-kD antibodies were used to screen a rat liver cDNA library in lambda GT-11 expression vector. 12 immunopositive clones were obtained. Crossreactivities between fusion proteins of these clones and the 50-kD protein was demonstrated, and four clones were analyzed by restriction mapping, one of them by nucleotide sequencing. Complete identity was found between the restriction maps of two clones (LKMC1 and LKMC2) and that of the 5' end of the rat cytochrome P450 db2. Sequence of a 608-bp fragment of LKMC1 showed complete homology with the rat P450 db2 form. The restriction map of the other two clones (LKMC3 and LKMC4) was identical to that of rat P450 db1. These results suggest that the antigen recognized by LKMA is a P450 of the IID subfamily.
自身免疫性肝炎患儿血清中针对大鼠肝内质网50-kD蛋白的抗体滴度很高。用亲和纯化的抗50-kD抗体筛选λGT-11表达载体中的大鼠肝cDNA文库。获得了12个免疫阳性克隆。证实了这些克隆的融合蛋白与50-kD蛋白之间的交叉反应性,对4个克隆进行了限制性酶切图谱分析,其中1个进行了核苷酸测序。发现两个克隆(LKMC1和LKMC2)的限制性酶切图谱与大鼠细胞色素P450 db2 5'端的图谱完全一致。LKMC1的一个608-bp片段的序列与大鼠P450 db2形式完全同源。另外两个克隆(LKMC3和LKMC4)的限制性酶切图谱与大鼠P450 db1的相同。这些结果表明,LKMA识别的抗原是IID亚家族的一种细胞色素P450。