Studies using a mouse B16 melanoma model have further demonstrated a higher efficacy of the protective IgG2a antibody TA99 in Fcgr2b–/– mice compared with WT mice (17), as demonstrated by an approximately 30-fold greater reduction in the volume of lung metastases in Fcgr2b–/– mice compared with WT mice. Here, FCGR2B is linked to melanoma.