Inefficient ZAP70-Signaling Blunts Antigen Detection by CAR-T-Cells

Gudipati, V.; Rydzek, J.; Doel-Perez, I.; Scharf, L.; Königsberger, S.; Einsele, H.; Stockinger, H.; Hudecek, M.; Huppa, J. B.

doi:10.1101/720417

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bioRxiv · 10.1101/720417

Inefficient ZAP70-Signaling Blunts Antigen Detection by CAR-T-Cells

Gudipati, V.·Rydzek, J.·Doel-Perez, I.·Scharf, L.·Königsberger, S.·Einsele, H.·Stockinger, H.·Hudecek, M.·Huppa, J. B.

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Abstract

Rational design of chimeric antigen receptors (CARs) with optimized anti-cancer performance mandates detailed knowledge of how CARs engage tumor antigens and how antigen-engagement triggers activation. We analyzed CAR-mediated antigen recognition via quantitative single molecule live-cell imaging and found the sensitivity of CAR-T-cells towards antigen approximately 1000-times reduced when compared to T-cell antigen receptor (TCR)-mediated recognition of nominal peptide/MHC complexes. While CARs outperformed TCRs with regard to antigen binding within the immunological synapse, proximal signaling was significantly attenuated due to inefficient recruitment of the tyrosine-kinase ZAP70 to ligated CARs and its reduced concomitant activation and subsequent release. Our study exposes signaling deficiencies of state-of-the-art CAR-designs, which limit at present the efficacy of CAR-T-cell therapies to target tumors with diminished antigen expression.

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Gudipati, V., Rydzek, J., Doel-Perez, I., Scharf, L., Königsberger, S., Einsele, H., Stockinger, H., Hudecek, M., Huppa, J. B.. 2019-07-30. Inefficient ZAP70-Signaling Blunts Antigen Detection by CAR-T-Cells. https://doi.org/10.1101/720417

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