Consecutive ibrutinib treatment for more than 20 weeks can augment CAR-T cells’ ability in the aspects of proliferation, persistence, and cytotoxicity in vitro and in vivo, while also promote the reconstitution of cellular immune by reducing the expression of immunosuppressive molecule PD-1 on CD8+ T cells and CD200 on B-CLL cells, increasing the IFN-γ secretion of CD8+ T cells, inhibiting IL-2 inducible T-cell kinase in CD4+ T cells, driving CD4+ T cells to develop into T helper 1-type, and increasing T cell repertoire diversity [74, 75]. Here, CD4 is linked to B-cell chronic lymphocytic leukemia.