Anaphylactic properties of mouse monoclonal IgG2a antibodies

摘要: Abstract Mouse monoclonal antibodies (10 hybridoma specific for soluble antigens, 8 H-2 K D and 9 myeloma immunoglobulins, among which 5 had a known specificity) of the IgG1, IgG2a, IgG2b, IgG3, IgA, IgM isotypes were studied their ability to induce mouse mast cell degranulation in vitro, presence antigen or after heat aggregation. Monoclonal IgG1 antibodies, as well behaved polyclonal corresponding classes: all induced with typical characteristics IgG-mediated anaphylactic reactions, whereas did not. By contrast, 2 IgG2a 3 intense that could not be explained by contamination IgG1-IgG2a hybrid molecules. IgG2a-mediated reactions observed four different situations: antigen-hybridoma complexes, antigen-bearing cells challenged anti-H-2, heat-aggregated antigen-myeloma complexes. The conclusion was reached activated through noncytotoxic, complement-independent mechanism involving Fcγ receptors.