A screening program for anti-DR typing reagents.
A total of 694 sera have been tested in a screening program aimed at identifying monospecific reagents for HLA--DR typing. All sera were first tested on a panel of enriched B and T cells without absorption on platelets. Only sera reacting more frequently on B than on T lymphocytes were absorbed on platelets and retested on the panel. This procedure saved a considerable amount of platelets and proved to be reasonably efficient. One-hundred-and-fifty sera were found to contain an anti-B cell antibody. Significantly less frequent B cell reactivity was found when HLA--A, --B, --C antibodies could not be detected. Twenty-five sera were demonstrated to be specific for well-defined DR antigens.