CTLA4 and neoplasm: Homozygous tumor-bearing hOX40tg mice were treated days 10, 13 and 17 with vehicle, ATOR-1015 or the surrogate anti-CTLA-4 antibodies 9D9 (mouse IgG2a) or 9H10 (hamster IgG), the latter being a more effective Treg depleter.