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bioRxiv · 10.1101/2023.01.04.522664

Programmable Drug Control of Receptor Valency Modulates the Potency of Cell Therapeutics

Abstract

Designer T cells offer a novel paradigm for treating diseases like cancer, yet they are often hindered by target recognition evasion and limited in vivo control. To overcome these challenges, we develop valency-controlled receptors (VCRs), a novel class of synthetic receptors engineered to enable precise modulation of immune cell activity. VCRs use custom-designed valency-control ligands (VCLs) to modulate T cell signaling via spatial molecular clustering. Using multivalent DNA origami as VCL, we first establish that valency is important for tuning the activity of CD3-mediated immune activation. We then generate multivalent formats of clinically relevant drugs as VCL and incorporate VCR into the architecture of chimeric antigen receptors (CARs). Our data demonstrate that VCL-mediated VCRs can significantly amplify CAR activities and improve suboptimal CARs. Finally, through medicinal chemistry, we synthesize programmable, bioavailable VCL drugs that potentiate targeted immune response against low-antigen tumors both in vitro and in vivo. Our findings establish receptor valency as a core mechanism for enhancing CAR functionality and offer a synthetic chemical biology platform for strengthening customizable, potent, and safer cell therapies.

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BibTeXRIS

Finn, P., Chavez, M., Chen, X., Wang, H., Rane, D. A., Gurjar, J., Qi, L. S.. 2023-01-04. Programmable Drug Control of Receptor Valency Modulates the Potency of Cell Therapeutics. https://doi.org/10.1101/2023.01.04.522664

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