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bioRxiv · 10.1101/2024.02.22.581571

Rational protein engineering to enhance MHC-independent T cell receptors

Chang, J.·Landmann, J. H.·Chang, T.-C.·Tenzin, Y.·Warrington, J. M.·Selli, M. E.·Ritchey, J.·Hsu, Y.-S.·Slade, M.·Gupta, D. K.·DiPersio, J. F.·Singh, N.
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Abstract

Chimeric antigen receptor (CAR)-based therapies have pioneered synthetic cellular immunity against cancer, however remain limited in their scope and long-term efficacy. Emerging data suggest that dysregulated CAR-driven T cell activation causes T cell dysfunction and therapeutic failure. To re-engage the endogenous T cell response, we designed hybrid MHC-independent T cell receptors (miTCRs) by linking antibody variable domains to TCR constant domains. While functional, we observed stark differences in miTCR-driven T cell function that were dependent on receptor orientation. Using predictive structural modeling, we observed significant biochemical conflicts at the hybrid variable-constant domain interface. To overcome this, we performed iterative sequence modifications and structural modeling to design a panel of miTCR variants predicted to have improved interface stability. Functional screening nominated a variant with superior efficacy to all other miTCRs as well as a standard CAR against high burdens of leukemia. Statement of SignificanceImproving the durability of engineered T cell immunotherapies is critical to enhancing efficacy. We used structure-informed design to evolve MHC-independent T cell receptors that drive improved tumor control. This work underscores the central role of synthetic receptor structure on T cell function and provides a framework for improved receptor engineering.

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Chang, J., Landmann, J. H., Chang, T.-C., Tenzin, Y., Warrington, J. M., Selli, M. E., Ritchey, J., Hsu, Y.-S., Slade, M., Gupta, D. K., DiPersio, J. F., Singh, N.. 2024-02-23. Rational protein engineering to enhance MHC-independent T cell receptors. https://doi.org/10.1101/2024.02.22.581571

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