Immunoprecipitation of cell surface CD84 protein. Detergent lysates of surface-labeled Raji cell line, 300.19 cells transfected with HLy9-β, and 300.19 untransfected cells were immunoprecipitated with the 2G7 plus 152-1D5. The immunoprecipitated materials were treated with or without N-glycosidase (PNGase F ) and analyzed under reducing conditions on a 10% SDS-polyacrylamide gel. Molecular weights (kD) were determined by the migration of a known protein standard.