Orthogonalized human protease control of secreted signals

Aldrete, C. A.; Vlahos, A. E.; Pei, J.; Cong, Q.; Gao, X. J.

doi:10.1101/2024.01.18.576308

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bioRxiv · 10.1101/2024.01.18.576308

Orthogonalized human protease control of secreted signals

Aldrete, C. A.·Vlahos, A. E.·Pei, J.·Cong, Q.·Gao, X. J.

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Abstract

Synthetic circuits that regulate protein secretion in human cells could support cell-based therapies by enabling control over local environments. While protein-level circuits enable such potential clinical applications, featuring orthogonality and compactness, their non-human origin poses a potential immunogenic risk. Here, we developed Humanized Drug Induced Regulation of Engineered CyTokines (hDIRECT) as a platform to control cytokine activity exclusively using human-derived proteins. We sourced a specific human protease and its FDA-approved inhibitor. We engineered cytokines (IL-2, IL-6, and IL-10) whose activities can be activated and abrogated by proteolytic cleavage. We utilized species specificity and re-localization strategies to orthogonalize the cytokines and protease from the human context that they would be deployed in. hDIRECT should enable local cytokine activation to support a variety of cell-based therapies such as muscle regeneration and cancer immunotherapy. Our work offers a proof of concept for the emerging appreciation of humanization in synthetic biology for human health.

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Aldrete, C. A., Vlahos, A. E., Pei, J., Cong, Q., Gao, X. J.. 2024-01-22. Orthogonalized human protease control of secreted signals. https://doi.org/10.1101/2024.01.18.576308

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