KLRB1 and leukemia: Compared with PBMC15CAR-NKT cells, Allo15BCAR-NKT cells exhibited enhanced killing of BCMA− tumor cells, particularly those sensitive to NKR-mediated cytotoxicity (for example, human melanoma cell line A375 and leukemia line K562), aligning with their heightened NKR expressions (Fig. 7d,g).