A genetically engineered human IgG mutant with enhanced cytolytic activity.

摘要: A mutant chimeric anti-5-dimethylaminonaphthalene-1-sulfonyl human Ig gamma that exhibited augmented effector function was constructed. Utilizing directed mutagenesis, a serine residue near the carboxyl terminus of IgG1 H chain (Ser444) replaced by cysteine. Novel intermolecular disulfide bonds between Cys444 residues linked pairs "tail-to-tail" to form covalent dimers ((H2L2)2). These were 200-fold more efficient, compared with monomeric IgG1, at antibody-dependent complement-mediated cytolysis hapten-bearing erythrocytes. The ability enhance cytolytic activity an mAb genetic engineering may be value in immunotherapy.