[Cooperative effects during interaction of monoclonal antibodies with insulin dimers].

The interaction of monoclonal antibodies of three types with the ATP-labeled insulin dimer was studied by the luminescent immunocofactor method. It was shown that the effective equilibrium binding constant increases at equimolar antigen/antibody concentrations. This can be due to the formation of multimolecular complexes between the antigens and antibodies. The feasibility of the binding constants increase during the formation of cyclic tetramolecular complexes is considered. A theoretical model for the description of interaction between the bivalent antigen and antibodies based on the increase of the binding constant during the formation of cyclic complexes is proposed. The coefficients of binding constant increase for antigens belonging to three different clones were calculated.