title: A novel covalent modification of antibodies at their amino groups with retention of antigen-binding activity.
abstract: A novel method of covalent modification of antibodies at their amino groups with retention of antigen-binding activity is described. The procedure is as follows: (a) blockade of those amino groups of antibodies whose integrity is essential to their antigen-binding activity with 2,3-dimethylmaleic anhydride, a reversible amino group-blocking reagent; (b) modification of residual amino groups with reagents reactive with the amino groups; and (c) removal of dimethylmaleyl groups by hydrolysis. This procedure was used for covalent conjugation of methotrexate (MTX) with two monoclonal antibodies against human melanoma-associated antigens using MTX N-succinimidyl ester. MTX attached to the antibodies at sites other than the amino groups via less stable bond(s) was removed by treatment with hydroxylamine.
authors: Department of Medicinal Chemistry and Biochemistry, Teijin Institute for Biomedical Research, Tokyo, Japan.
authors: N
authors: N
authors: Endo
authors: N
authors: N
authors: Umemoto
authors: Y
authors: Y
authors: Kato
authors: Y
authors: Y
authors: Takeda
authors: T
authors: T
authors: Hara
mesh_terms: D000588:Amines; D000818:Animals; D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D001666:Binding Sites, Antibody; D055598:Chemical Phenomena; D002621:Chemistry; D008299:Maleic Anhydrides; D008545:Melanoma / Q000276:immunology; D058950:Melanoma-Specific Antigens; D008727:Methotrexate; D051379:Mice; D009363:Neoplasm Proteins / Q000276:immunology
chemical_list: D000588:Amines; D000911:Antibodies, Monoclonal; D000951:Antigens, Neoplasm; D008299:Maleic Anhydrides; D058950:Melanoma-Specific Antigens; D009363:Neoplasm Proteins; C007474:2,3-dimethylmaleic anhydride; D008727:Methotrexate