CD28 and neoplasm: In addition, armored CAR-T cells include a CAR with co-expression of both CD28 and 4-1BB in the costimulatory domain, IL-18 secreting CARs to induce enhanced proliferation and prolonged persistence, PD-1 blocking scFv secreting CARs, IL-18 secreting CARs, and CARs including CD40 ligand to stimulate anti-tumor response [165].