PDCD1 and lymphoma: To determine if PD-1 blockade, with or without CTLA-4 blockade, enhances the ability of cord blood T cells to control EBV-induced lymphomas in cord blood-humanized NSG mice, mice injected with EBV-infected cord blood were treated with or without monoclonal antibodies directed against the PD-1 or CTLA-4 receptors, alone or in combination (100 μg per mouse i.p. delivered three times a week starting 5 days after injection of cord blood cells).