Parsons K R, Sopp P, Jones B V, Bland P, Howard C J
Institute for Animal Health, Compton, Newbury, Berkshire, UK.
Immunology. 1996 Jan;87(1):64-70.
An antigen has been identified, recognized by a novel monoclonal antibody CC45, which is expressed by a subpopulation of bovine gamma/delta T-cell receptor-positive (gamma/delta TCR+) T cells restricted in their distribution to the intestinal epithelium. This subset of intestinal intraepithelial lymphocytes (iIEL) which represented 8-29% of gamma/delta TCR+ T cells in the gut epithelium expressed CD45, CD3 and L-selectin; most of these cells were CD2- and CD8-. Electron microscopic studies of CC45+ cells revealed that they were large mononuclear leucocytes containing numerous mitochondria and smooth vesicles; a proportion of these contained membrane-bound dense granules. Immunoprecipitation of 125I-labelled iIEL analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis under reducing and non-reducing conditions revealed polypeptides of 60,000 and 200,000 molecular weights, respectively indicating that the antigen, which appears distinct from molecules described in other species, is expressed on the cell surface as a complex.
一种抗原已被鉴定出来，它可被一种新型单克隆抗体CC45识别，该抗原由牛γ/δ T细胞受体阳性（γ/δ TCR+）T细胞的一个亚群表达，其分布局限于肠上皮。肠道上皮内淋巴细胞（iIEL）的这个亚群占肠道上皮中γ/δ TCR+ T细胞的8%-29%，表达CD45、CD3和L-选择素；这些细胞大多数为CD2-和CD8-。对CC45+细胞的电子显微镜研究显示，它们是含有大量线粒体和平滑小泡的大单核白细胞；其中一部分含有膜结合致密颗粒。在还原和非还原条件下，通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳对125I标记的iIEL进行免疫沉淀，分别显示出分子量为60,000和200,000的多肽，这表明该抗原在细胞表面以复合物形式表达，且与其他物种中描述的分子不同。
