CD27 and neoplasm: The advantages of sustained Treg depletion and the presence of APC, together with direct and indirect effects of CD27 costimulatory signaling, allows the conditioning treatment with varlilumab to potentiate the transferred T cells and enable the responses of recipient’s endogenous T cells to TAAs derived from a growing tumor or vaccination [24, 30, 31], thus extending antitumor immunity beyond the single target recognized by CAR-T cells or TCR-T cells.