Patent ID: 7807416

Claim:
A method of producing an antibody with increased antibody-dependent cytotoxicity activity as compared with that of an antibody produced by an antibody-producinq cell comprising: inhibiting mismatch repair in said antibody-producing cell by introducing into said antibody-producing cell a dominant negative allele of a PMS2 gene encoding a truncated PMS2 polypeptide comprising the amino acid sequence of SEQ ID NO: 15, whereby said antibody-producing cell becomes hypermutable; allowing said hypermutable antibody-producing cell to grow, thereby generating a population of hypermutable antibody-producing cells; and screening said hypermutable antibody-producing cells for cells that produce antibodies with increased antibody-dependent cytotoxicity activity, which retain the antigen binding specificity of the antibody produced by said antibody-producinq cells, and optionally isolating said antibodies with increased antibody-dependent cytotoxicity activity.