Activation of mouse complement by different classes of mouse antibody.
The capacity of mouse IgM, IgGl, IgG2 and IgA anti-dinitrophenyl (DNP) antibodies to activate mouse or guinea-pig complement was studied, using a sensitive haemolytic assay and two-dimensional immunoelectrophoresis to detect cleavage of mouse C3. Three monoclonal IgM antibodies, and a heterogeneous IgM fraction, lysed trinitrophenylated erythrocytes in the presence of guinea-pig C, but failed to produce lysis in the presence of mouse C. and only activated mouse C3 very inefficiently. A monoclonal IgGl antibody did not produce haemolysis in the presence of guinea-pig or mouse C, but cleaved mouse C3 via the alternative pathway. Two IgA myeloma proteins (M315 and M460) had similar properties. A heterogeneous IgG2 antibody fraction produced haemolysis in the presence of both mouse and guinea-pig C, and was shown to activate both the classical and alternative pathways of mouse C.
D000818:Animals; D003176:Complement C3 / Q000276:immunology*; D003168:Complement Fixation Tests; D003165:Complement System Proteins / Q000276:immunology*; D004136:Dinitrobenzenes / Q000276:immunology; D004912:Erythrocytes / Q000276:immunology; D006168:Guinea Pigs; D006433:Hemocyanins / Q000276:immunology; D006461:Hemolysis; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007136:Immunoglobulins / Q000145:classification*; D051379:Mice; D008807:Mice, Inbred BALB C; D011817:Rabbits; D012756:Sheep; D014301:Trinitrobenzenes / Q000276:immunology
D003176:Complement C3; D004136:Dinitrobenzenes; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007075:Immunoglobulin M; D007136:Immunoglobulins; D014301:Trinitrobenzenes; D003165:Complement System Proteins; D006433:Hemocyanins