Murine cell surface glycoproteins. Characterization of a major component of 80,000 daltons as a polymorphic differentiation antigen of mesenchymal cells.
Murine cell surface glycoproteins. Characterization of a major component of 80,000 daltons as a polymorphic differentiation antigen of mesenchymal cells.
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鼠细胞表面糖蛋白。
DOI：
10.1016/s0021-9258(19)69093-9
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发表时间：
1981
期刊：
影响因子：
--
通讯作者：
J. August
中科院分区：
文献类型：
--
作者：
E. Hughes;G. Mengod;J. August
用NIH/3 T3细胞膜免疫大鼠，取其脾细胞与小鼠骨髓瘤细胞融合，制备了抗NIH/3 T3细胞表面抗原的单克隆抗体。在已经研究的40种抗体中，有4种似乎与同种异体特异性抗原决定簇反应：它们与NIH/3 T3细胞结合，但不与BALB/3 T3细胞结合。这四种抗体中的每一种免疫沉淀约80，000道尔顿的糖蛋白，其迁移至约pH 5.0的等电点。相同的分子量和等电点，并产生相同的蛋白水解裂解片段的多肽，存在于BALB/3 T3细胞，但没有抗原反应性。80，000-道尔顿糖蛋白是质膜的主要成分。它是完整NIH/3 T3细胞的主要乳过氧化物酶碘化组分，125 I标记抗体的饱和结合表明每个细胞约有10（6）个抗原位点。免疫反应性糖蛋白在不同品系小鼠中的分布研究证实了该决定簇的多态性表达：BALB/c、DBA/1、DBA/2和CBA小鼠的脾细胞不结合抗80，000-道尔顿糖蛋白单克隆抗体，而大量其他品系小鼠的脾细胞对抗体结合呈阳性。抗原反应性在不同细胞系中显著不同，并且在NIH/3 T3小鼠胚胎成纤维细胞、G8-1 Swiss韦伯斯特成肌细胞和IC-21 SV 40转化的C57 BL/6小鼠腹腔巨噬细胞中最大。该80，000-道尔顿糖蛋白的性质表征了该分子作为小鼠间充质细胞的新的细胞表面分化同种异体抗原。
Monoclonal antibodies reactive with NIH/3T3 cell surface antigens were obtained from hybridomas of murine myeloma cells fused to spleen cells of rats immunized with NIH/3T3 cell plasma membranes. Four of the antibodies, of forty that have been studied, appeared to react with allospecific antigenic determinants: they bound to NIH/3T3 cells but not to BALB/ 3T3 cells. Each of these four antibodies immunoprecipitated a glycoprotein of about 80,000 daltons that migrated to an isoelectric point of about pH 5.0. Polypeptides of identical molecular weight and isoelectric points, and yielding the same proteolytic cleavage fragments, were present in BALB/3T3 cells, but were not antigenically reactive. The 80,000-dalton glycoprotein was a major constituent of the plasma membrane. It was a predominant lactoperoxidase iodinated component of intact NIH/3T3 cells, and saturation binding of 125I-labeled antibody indicated that there were about 10(6) antigenic sites/cell. Studies of the distribution of the immunoreactive glycoprotein among different strains of mice confirmed the polymorphic expression of the determinant: Spleen cells of BALB/c, DBA/1, DBA/2, and CBA mice did not bind anti-80,000-dalton glycoprotein monoclonal antibodies, whereas spleen cells of a large number of other strains of mice were positive for antibody-binding. The antigenic reactivity varied markedly among different cell lines and was greatest with the NIH/3T3 mouse embryo fibroblast, G8-1 Swiss Webster myoblast, and IC-21 SV40-transformed C57BL/6 mouse peritoneal macrophage. The properties of the 80,000-dalton glycoprotein characterized this molecule as a new cell surface differentiation alloantigen of murine mesenchymal cells.