Disclosed are processes for producing a variant polypeptide (e.g. antibodies) having increased binding affinity for an FcγR, which processes comprise modifying the polypeptides by substitution of the amino acid at position 268 of a human IgG CH2 region for a non-native polar or charged amino acid e.g. Gin, Asn, Glu, or Asp. also provided are corresponding polypeptides, nucleic acids, and methods of use of the same e.g. in improved lytic therapies.