The present invention relates to an antibody which has a therapeutic effect on cancer, autoimmune diseases or inflammatory diseases. Namely, the present invention relates to an antibody which exhibits an apoptosis-mediated cytotoxic activity on a cell expressing a death domain-containing receptor. The present invention addresses the problem of providing a drug which has a therapeutic effect on cancer. The present invention clarifies that a novel anti-DR5 antibody, which is capable of inducing apoptosis in a cell, has a remarkable cytotoxic activity compared with the conventional anti-DR5 antibodies.
