The present invention relates to Fc region-containing polypeptides that exhibit improved
effector function due to alterations of the extent of
fucosylation, and to methods of using such polypeptides for treating or preventing
cancer and other diseases. The Fc region-containing polypeptides of the present invention are preferably immunoglobulins (e.g., antibodies), in which the Fc region comprises at least one
amino acid substitution relative to the corresponding
amino acid sequence of a
wild type Fc region, and which is sufficient to attenuate post-translational
fucosylation and mediate improved binding to an activating
Fc receptor and reduced binding to an inhibitory
Fc receptor. The methods of the invention are particularly useful in preventing, treating, or ameliorating one or more symptoms associated with a
disease, disorder, or infection where either an enhanced
efficacy of
effector cell function mediated by FcγR is desired (e.g.,
cancer, infectious
disease) or an inhibited
effector cell response mediated by FcγR is desired (e.g.,
inflammation,
autoimmune disease).