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bioRxiv · 10.1101/2023.04.08.536099

Bioorthogonal photocatalytic quinone methide decaging for cell-cell interaction labeling

Zhang, Y.·Liu, S.·Guo, F.·Qin, S.·Zhou, N.·Fan, X.·Chen, P. R.
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Abstract

Cell-cell interactions (CCIs) play crucial roles in directing diverse biological processes in multicellular organisms, making the high-sensitivity and selectivity characterization of the diverse CCIs in high demand yet still challenging. We herein introduced a bioorthogonal photocatalytic quinone methide decaging-enabled cell-cell interaction labeling strategy (CAT-Cell) for sensitive and spatiotemporally resolved profiling of multitype CCIs. By adapting an optimized quinone methide probe for interacting cell labeling, we demonstrated the excellent capacity of CAT-Cell for capturing CCIs directed by various receptor-ligand pairs (e.g., CD40-CD40L, TCR-pMHC) and further showed its compatibility with tumor-specific targeting systems. Finally, we used CAT-Cell to detect cytotoxic cells (e.g., antigenspecific T cells, Natural Killer cells) in mouse models containing splenocyte mixtures and tumor samples. By leveraging the bioorthogonal photocatalytic decaging chemistry, CAT-Cell offers as a nongenetic, non-invasive and universal toolbox for profiling diverse CCIs under physiological-relevant settings.

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Zhang, Y., Liu, S., Guo, F., Qin, S., Zhou, N., Fan, X., Chen, P. R.. 2023-04-08. Bioorthogonal photocatalytic quinone methide decaging for cell-cell interaction labeling. https://doi.org/10.1101/2023.04.08.536099

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