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bioRxiv · 10.1101/2021.03.10.434884

CD36 family members are TCR-independent ligands for CD1 antigen-presentingmolecules

Abstract

CD1c presents lipid-based antigens to CD1c-restricted T cells which are thought to be a major component of the human T cell pool. The study of CD1c-restricted T cells, however, is hampered by the presence of an abundantly expressed CD1c-binding partner on blood cells distinct to the T cell receptor (TCR), confounding analysis of TCR-mediated CD1c tetramer staining. Here, we identify the CD36 family (CD36, CD36-L1 and CD36-L2) as novel ligands for CD1c, CD1b and CD1d proteins, and show that CD36 is the receptor responsible for non-TCR-mediated CD1c tetramer staining of blood cells. Moreover, CD36-blockade enables tetramer-based identification of CD1c-restricted T cells and clarifies identification of CD1b- and CD1d-restricted T cells. We use this technique to characterise CD1c-restricted T cells ex vivo and show diverse phenotypic features, TCR repertoire and antigen-specific subsets. Accordingly, this work will enable further studies into the biology of CD1 and human CD1-restricted T cells. One Sentence SummaryCD1 molecules bind CD36 family members and blockade of this interaction facilitates the study of CD1-restricted T cells.

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BibTeXRIS

Gherardin, N. A., Redmond, S. J., McWilliam, H. E., Almeida, C. F., Gourley, K. H., Seneviratna, R., Li, S., De Rose, R., Nguyen-Robertson, C. V., Su, S., Ritchie, M., Villadangos, J. A., Moody, D. B., Pellicci, D. G., Uldrich, A. P., Godfrey, D. I.. 2021-03-11. CD36 family members are TCR-independent ligands for CD1 antigen-presentingmolecules. https://doi.org/10.1101/2021.03.10.434884

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