Automated rosetting assay for cell surface antigens and autorosetting lymphocytes

An automated procedure, using a Coulter counter, is described for enumerating rosette-forming lymphocytes in 2 rosetting systems in mice, detecting antibodies to cell surface antigens, and the interaction of autologous erythrocytes with thymocytes (autorosetting). The procedure gives results comparable with determinations of rosettes by light microscopy. The procedure not only estimates rosetting percentages, but can be used to titrate anti-lymphocyte antibodies, to detect autorosette inhibition factor in serum and to assay cell surface antigens in detergent lysates of spleen cells.