ACT also could be optimized by integration of the cytokine gene into the lentiviral vector that encodes the CARs, such as the anti-CD19 CAR-T or CAR-NK cells incorporated with IL-15 and inducible caspase-9 suicide genes (iC9/CAR.19/15) [124,125], anti-GD2 CAR-T cells with an IL-15 gene to target neuroblastoma (GD2.CAR/15) [126], and IL-15 trispecific killer engager (TriKE) containing single-chain Fv against CD16 and CD33 (as known as 161533) [127,128]. The gene discussed is IL15; the disease is neuroblastoma.