期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1993
卷号:90
期号:8
页码:3418-3422
DOI:10.1073/pnas.90.8.3418
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:We have recently described a murine lymphocyte protein, provisionally termed sgp-60, which is expressed on virtually all lymphocytes of both T- and B-cell origin. A hamster monoclonal antibody to sgp-60 can inhibit interleukin-2 (IL-2) production, IL-2-receptor expression, and T-cell proliferation, events normally observed after stimulation of T cells with an antibody to the T-cell receptor/CD3 complex or with the lectin concanavalin A. Our previous studies did not reveal the molecular nature of the sgp-60 antigen. Purification of sgp-60 and protein sequencing demonstrate that sgp-60 is identical to the CD48 antigen, a ligand for the CD2 antigen, which is also called Blast-1 in humans, BCM1 in mice, and OX-45 in rats. The identity of sgp-60 and CD48 was independently confirmed in gene transfection experiments. The anti-sgp-60 monoclonal antibody was selectively reactive with COS-7 cells transfected with a BCM1 cDNA clone but not with Kb-transfected controls. The results of the present report, together with our previous functional studies, may have implications for the role of CD2 and CD48 in murine T-cell activation.