A class of {gamma}{delta} T cell receptors recognize the underside of the antigen-presenting molecule MR1

We describe a diverse population of human T cells isolated from peripheral blood and tissues that exhibit autoreactivity to the monomorphic MHC-related protein 1 (MR1). The crystal structure of a TCR–MR1–antigen complex starkly contrasts with all other TCR–MHC and TCR–MHC-I-like complex structures. Namely, the TCR binds underneath the MR1 antigen-binding cleft, where contacts are dominated by the MR1 α3 domain. A similar pattern of reactivity was observed for diverse MR1-restricted TCRs from multiple individuals. Accordingly, we simultaneously report MR1 as a ligand for human T cells and redefine the parameters for TCR recognition.

Source: ScienceNOW - December 18, 2019 Category: Science Authors: Le Nours, J., Gherardin, N. A., Ramarathinam, S. H., Awad, W., Wiede, F., Gully, B. S., Khandokar, Y., Praveena, T., Wubben, J. M., Sandow, J. J., Webb, A. I., von Borstel, A., Rice, M. T., Redmond, S. J., Seneviratna, R., Sandoval-Romero, M. L., Li, S., Tags: Immunology reports Source Type: news