BIOCHEMICAL-ANALYSIS OF MOLECULES REACTIVE WITH MONOCLONAL-ANTIBODIESSPECIFIC FOR PORCINE CD45

The apparent molecular weight of molecules reactive with eight mAbs, w hich were identified during the First International Swine CD Workshop as putatively specific for porcine CD45, was determined by immunopreci pitation analysis of I-125 surface-labeled peripheral blood mononuclea r cells. Four putative CD45 specific mAbs (K252.1E4, MAC323, 74-9-3 an d 2A5) precipitated three polypeptides of 226, 210 and 190 kDa. Two pu tative CD45R specific mAbs (MAC326 and MAC327) precipitated two polype ptides with an apparent molecular weight of 226 and 210 kDa, while ano ther two (3a56 and -a2) precipitated a single polypeptide of 210 kDa. Sequential immunoprecipitations analyses indicated that the comigratin g molecules precipitated by the CD45 and CD45R were the same. The resu lts from this study confirmed the assignment of mAbs K252.1E4, MAC323, 74-9-3 and 2A5 as CD45, and mAbs MAC326, MAC327, 3a56 and -a2, as CD4 5R. These CD45 and CD45R specific mAbs should prove to be valuable rea gents for the study of the porcine immune system.