PDCD1 and neoplasm: In addition, when combined with PD-1 blocking antibody, anti-mLAG-3 IgG1 (D265A) showed significantly synergistic anti-tumor effects, whereas anti-mLAG-3 IgG2a with intact effector function in combination with an anti-mouse PD-1 antibody was less efficacious than anti-mouse PD-1 alone, suggesting that the effector function of LAG-3 antibody might interfere with anti-mouse PD-1 mediated efficacy.