Differentiation of C3b receptors on human lymphocytes, phagocytes, erythrocytes and renal glomerulus cells by monoclonal antibodies.

C3b receptor protein was purified from human erythrocytes by 2 M KBr solubilization and affinity chromatography on C3-coated sepharose. This material served as antigen for raising monoclonal antibodies. To investigate the distribution and anti- genetic relationship between the receptors for C3b on human erythrocytes, lymphoid and phagocytic cells, as well as kidney cells three monoclonal antibodies were selected which inhibited the binding of EAC14°23b to complement receptor-bearing cells. This could be shown for human erythrocytes by inhibiting the immune adherence reaction, for tonsil lyme phocytes, Raji cells, and guinea-pig spleen cells by inhibition of rosette formation of these cells with EAC14°23b, and for human renal &omeruli by blocking of the adherence of EAC14°23b to kidney sections. In contrast, these monoclonal antibodies were not capable of inhibiting rosette formation of human granulocytes and monocytes with EAC14°23b. The antibodies only interfered with the rosette formation, of EAC14°23b and EAC 14°23d with Raji cells and tonsil lymphocytes--if at all--at high concentrations, whereas the rosette formation of Raji cells and tonsil lymphocytes with EAC14°23b was influenced by supernatants of the selected clones up to a dilution of 1:10³ to 1:10⁵. [ABSTRACT FROM AUTHOR]