PBMCs (culture with 100 IU of IL-2/mL 1640 complete medium) were incubated with MM.1S-luc cells or NCI H929-luc cells in the presence of BK1 for 6 hours, and the results showed that BK1 significantly improved the specific lytic ability of PBMCs against BCMA+ tumor cells in a concentration-dependent manner (Figures 2A, B, S3). The gene discussed is TNFRSF17; the disease is neoplasm.