A novel α/β T-cell subpopulation defined by recognition of EPCR

Arrondo, E. E.; Moran-Garrido, M.; Saiz, J.; Barbas, C.; Dichiara Rodriguez, M. G.; Ramirez, N.; Lopez-Sagaseta, J.

doi:10.1101/2021.07.01.450412

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bioRxiv · 10.1101/2021.07.01.450412

A novel α/β T-cell subpopulation defined by recognition of EPCR

Arrondo, E. E.·Moran-Garrido, M.·Saiz, J.·Barbas, C.·Dichiara Rodriguez, M. G.·Ramirez, N.·Lopez-Sagaseta, J.

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Abstract

T-cell self-recognition of antigen presenting molecules is led by antigen-dependent or independent mechanisms. The endothelial protein C receptor (EPCR) shares remarkable similarity with CD1d, including a lipid binding cavity. We have identified EPCR-specific /{beta} T-cells in the peripheral blood of healthy donors. The average frequency in the CD3+ leukocyte pool is comparable to other autoreactive T-cell subsets that specifically bind MHC-like receptors. Alteration of the EPCR lipid cargo, revealed by X-ray diffraction studies, points to a prevalent, yet not exclusive, lipid-independent self-recognition. In addition, we solve the EPCR lipidome, and detect species not yet described as EPCR ligands. These studies report, for the first time, novel recognition by circulating /{beta} T-cells and provide grounds for EPCR and lipid mediated T-cell restriction.

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Arrondo, E. E., Moran-Garrido, M., Saiz, J., Barbas, C., Dichiara Rodriguez, M. G., Ramirez, N., Lopez-Sagaseta, J.. 2021-07-01. A novel α/β T-cell subpopulation defined by recognition of EPCR. https://doi.org/10.1101/2021.07.01.450412

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