Preparation of bispecific antibodies by chemical recombination of monoclonal immunoglobulin G1 fragments.

Preparation of bispecific antibodies by the chemical reassociation of monovalent fragments derived from monoclonal mouse immunoglobulin G1 is inefficient because of side reactions during reoxidation of the multiple disulfide bonds linking the heavy chains. These side reactions can be avoided by using specific dithiol complexing agents such as arsenite and effecting disulfide formation with a thiol activating agent such as 5,5'-dithiobis(2-nitrobenzoic acid). In this way bispecific antibodies were obtained in high yield and free of monospecific contaminants from monoclonal mouse immunoglobulin G1 fragments. The bispecific antibodies were used as agents for the selective immobilization of enzymes.