Point mutation in CD19 facilitates immune escape of B cell lymphoma from CAR-T cell therapy

BACKGROUND: of B cells after CAR-T cell infusion. METHODS: B cells from pre-relapse and postrelapse samples. CD19 in CARs comprising single chain fragments variable (scFV) antibody with FMC63 or 21D4 was constructed. The cytotoxic efficacy of CAR-T cells was also evaluated via in vitro and in vivo experiments. RESULTS: cells with loss of exon 1, 2, or 3. CONCLUSIONS: These findings suggest that point mutation can facilitate immune escape from CAR-T cell therapy and that alternative CAR-T cells can effectively eradicate the mutated B cells, providing an individualized therapeutic approach for lymphoma patients showing relapse.