Characterization of CD45 and CD45R monoclonal antibodies using transfected mouse cell lines that express individual human leukocyte common antigens.

Five cell lines that express one of five isoforms of the human leukocyte common Ag (CD45) were established by transfecting a murine pre-B cell line with leukocyte common Ag cDNA constructs. Using these cell lines, the specificities of CD45 and CD45R mAb were examined. Of the 43 mAb tested, 25 antibodies recognized sequences common to all five isoforms, 16 antibodies recognized isoforms that include exon A encoded sequences, one antibody recognized isoforms that include exon B encoded sequences, and one antibody recognized only the isoform that does not include either exon A, B, or C encoded sequences.