hFcγRI can mediate antibody-dependent protection from metastatic melanoma in transgenic mice. (A-D) Mice were injected intravenously with B16 luc2⁺ cells and with anti–TYRP-1 mAbs (TA99 or CTA99 or human anti–TYRP-1) where indicated. (C-E) Mice were also pretreated with anti-FcγRIV mAbs. Quantification of tumor load was performed on ex vivo explanted lungs on day 11 after injection of B16 luc2⁺ cells (A, n ≥ 5; B, n ≥ 5; C, n ≥ 4; D, n ≥ 4; E, n ≥ 4). Data are representative of at least 2 independent experiments and are represented as means ± SEM.