Work

Molecular basis underpinning MR1 allomorph recognition by an MR1-restricted T cell receptor

Year: 2025

Type: article

Abstract: Introduction: The MHC-class-I-related molecule MR1 presents small metabolites of microbial and self-origin to T cells bearing semi-invariant or variant T cell receptors. One such T cell receptor, MC.7.G5, was previously shown to confer broad MR1-restricted reactivity to tumor cells but not normal cells, sparking interest in the development of non-MHC-restricted immunotherapy approaches. Methods/Results: Here we provide cellular, biophysical, and crystallographic evidence that the MC.7.G5 TCR does not have pan-cancer specificity but is restricted to a rare allomorph of MR1, bearing the R9H mutation. Discussion: Our results underscore the importance of in-depth characterization of MR1-reactive TCRs against targets expressing the full repertoire of MR1 allomorphs.

Source: Frontiers in Immunology

DOI: 10.3389/fimmu.2025.1547664