Stereoselective Degradation of Diacylglycerol Kinases Potentiate T cell Activation and Tumor Cell Cytotoxicity

Shaikh, M.; Mookherjee, S. P.; Weckerly, C.; Libby, A. H.; Xiao, A.; Zhao, Y.; Vaidya, S. D.; Kim, A.; Li, Z.; Ware, M. L.; Marants, M.; Murtagh, O.; Wolfe, W. J.; Bullock, T. N.; Purow, B. W.; Hammond, G. R.; Hsu, K.

doi:10.64898/2025.12.09.692983

bioRxiv · 10.64898/2025.12.09.692983

Stereoselective Degradation of Diacylglycerol Kinases Potentiate T cell Activation and Tumor Cell Cytotoxicity

Shaikh, M.·Mookherjee, S. P.·Weckerly, C.·Libby, A. H.·Xiao, A.·Zhao, Y.·Vaidya, S. D.·Kim, A.·Li, Z.·Ware, M. L.·Marants, M.·Murtagh, O.·Wolfe, W. J.·Bullock, T. N.·Purow, B. W.·Hammond, G. R.·Hsu, K.

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Abstract

Stereoselective recognition is a powerful means to differentiate selective versus non-specific activity of small molecules in complex biological systems. Here, we disclose stereochemically defined, sulfonyl-triazole inhibitors of the lipid enzyme diacylglycerol kinase-alpha (DGK), a key metabolic checkpoint for T cell effector function. Acute treatment with the covalent DGK inhibitor AHL-7160 recruited endogenous DGK to the plasma membrane in a stereoselective and isozyme-specific manner. The membrane translocation activity of AHL-7160 correlated with blockade of cellular phosphatidic acid production and potentiation of primary T cell-mediated killing of a glioblastoma cell line. Quantitative chemoproteomics revealed Y669 and K411 as sites of AHL-7160 modification on endogenous DGK in cells. Extended treatments resulted in proteasome-dependent and proteome-wide selective degradation of DGK in T cells. Collectively, these findings establish covalent DGK ligands as potent molecular glues with translational potential in immunotherapy.

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Shaikh, M., Mookherjee, S. P., Weckerly, C., Libby, A. H., Xiao, A., Zhao, Y., Vaidya, S. D., Kim, A., Li, Z., Ware, M. L., Marants, M., Murtagh, O., Wolfe, W. J., Bullock, T. N., Purow, B. W., Hammond, G. R., Hsu, K.. 2025-12-12. Stereoselective Degradation of Diacylglycerol Kinases Potentiate T cell Activation and Tumor Cell Cytotoxicity. https://doi.org/10.64898/2025.12.09.692983

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