Nanobody Armed T Cells Endow CAR-T Cells the Ability to Against Lymphoma Cells

Abstract BackgroundTaking advantages of nanobody (Nb) in immunotherapy, here we investigate the cytotoxicity of Nb based Chimeric antigen receptor T cells (Nb CAR-T) against Lymphoma cells.MethodsCD19 Nb CAR-T, CD20 Nb CAR-T, and Bispecific Nb CAR-T cells were generated by panning anti-human CD19, CD20 specific nanobodies sequences from naive phage display library, then integrating Nb genes with lentiviral cassette that included other CARs elements, and finally transducing T cells that were expanded under optimization system with above prepared CARs lentiviruses. Prepared Nb CAR-T cells were co-cultured with tumor cell lines or primary tumor cells for 24 hours or 5 days to evaluate the biological function. ResultsObtained several Nb sequences specific to CD19 and CD20. Optimized culture conditions of T cells that expand 87.5 folds after 7 days of activation. Generated Nb CAR-T cells that could recognize Burkitt lymphoma cell lines (Raji and Daudi), induce activation, proliferation, and therefore kill target cells specifically. Furthermore, same results were also obtained from patient samples with cytotoxicity about 60%. ConclusionsOur study demonstrated that nanobody based single and bispecific CAR-T cells have certain killing ability against both tumor cell lines and patient-derived tumor cells in vitro.