In addition, PD-L1.BB CSR-modified dual-targeting CAR-T cells may have better adaptability to serous cavity metastases environment, since 4-1BB co-stimulated CAR-T cells were reported with an increased metabolic fitness.42 Moreover, PD-L1 is induced by IFN-γ expression in tumor cells,43 which may potentially enhance the stimulation of PD-L1.BB CSR leading to stronger fitness and activity in return. The gene discussed is IFNG; the disease is neoplasm.