Construction of anti-BCMA chimeric antigen receptor (CAR-BCMA) modified T cells and its cytotoxicity against tumor cells / 中国肿瘤生物治疗杂志

ABSTRACT

@# Objective： ：To explore a novel chimeric antigen receptor (CAR)-T cell treatment to treat Multiple Myeloma (MM) via target B cell maturation antigen (BCMA). Methods： ：A CAR-BCMA molecular was constructed based on mouse originated BCMA scFv, and was packaged into lentiviral vector and transfected into T cells from healthy donors to construct CAR-BCMA-T cells. The BCMApositive cell lines A549-BCMA, A549-BCMAOFP and K562-BCMA were constructed as target cells. Then, the CAR-BCMA-T cells were co-incubated with the constructed target cells and human myeloma U266 cells, and the cytotoxic effects of CAR-BCMA-T cells were evaluated via CCK-8 and FACS. Finally, the CAR-BCMA-T cells originated from MM patients were constructed, and its cytotoxicity against A549-BCMA were examined; in addition, the IFN-γ release level in CAR-BCMA-T cells was evaluated by ELISA and FACS. Results: After 11 days’incubation, the CAR-BCMA-T cells originated from healthy donors amplified 300 times with a positive rate of 43%. The BCMApositive target cell lines were constructed successfully. Under an effector target ratio of 51, the killing rates of CARBCMA-T cells against A549-BCMA, K562-BCMA and U266 were about 80%, 60%, and 80%, respectively, which were significantly higher than those against BCMA negative cells; and the cytotoxicity was related to the BCMA expression level in target cells. What’ s more, at the effector target ratio of 201, the CAR-BCMA-T cells originated from MM patients were demonstrated to exhibit a killing rate of more than 95% againstA549-BCMApositive cells, and produced large amount of IFN-γ. Conclusion: CAR-BCMA-T cells originated from both healthy and MM donors were successfully constructed, and they can effectively and specifically kill BCMA positive tumor cells.