Genetically engineered lymphocytes hold promise for the treatment of genetic disease, viral infections and cancer. However, current methods for genetic transduction of peripheral blood lymphocytes rely on viral vectors, which are hindered by production and safety-related problems. In this study, we demonstrated an efficient novel nonviral platform for gene transfer to lymphocytes. The Sleeping Beauty transposon-mediated approach allowed for long-term stable expression of transgenes at ∼50% efficiency. Utilizing transposon constructs expressing tumor antigen-specific T-cell receptor genes targeting p53 and MART-1, we demonstrated sustained expression and functional reactivity of transposon-engineered lymphocytes on encountering target antigen presented on tumor cells. We found that transposon- and retroviral-modified lymphocytes had comparable transgene expression and phenotypic function. These results demonstrate the promise of nonviral ex vivo genetic modification of autologous lymphocytes for the treatment of cancer and immunologic disease.
Bibliographical noteFunding Information:
We thank Dr Steven R Yant and Dr Mark A Kay of the Departments of Pediatrics and Genetics, Stanford University School of Medicine, Stanford, CA, for their generous gift of the Sleeping Beauty transposon plasmids and hyperactive transposase, as well as for their helpful suggestions on this project. We thank FACS lab and TIL lab in Surgery Branch for providing technical support and maintenance of tumor cells from patients. This work is supported by the Intramural Research Program of the National Institute of Health, National Cancer Institute, Center for Cancer Research.