How MR1 Presents a Pathogen Metabolic Signature to Mucosal-Associated Invariant T (MAIT) Cells
Hamish EG McWilliam, Jose A Villadangos
TRENDS IN IMMUNOLOGY | ELSEVIER SCI LTD | Published : 2017
Mucosal-associated invariant T (MAIT) cells are innate-like lymphocytes restricted by the antigen (Ag)-presenting molecule MHC class I (MHC I)-related protein 1 (MR1). The Ags presented by MR1 are vitamin B-related Ags (VitBAgs), 'building-block' metabolites of riboflavin that are synthesized by a range of microbes. MR1 presentation is thus a unique mechanism for the immune detection of a pathogen metabolic signature. While the full picture of how MR1 accomplishes this remains incomplete, recent data show that, unlike other MHC molecules, MR1 operates by a presentation-on-demand mechanism. In the absence of metabolite ligands MR1 is mostly stored in the endoplasmic reticulum (ER). Ligand bin..View full abstract
The authors gratefully acknowledge support from the Australian Research Council (DECRA Fellowship, H.E.G.McW.; Discovery Project, J.A.V.), the National Health and Medical Research Council (Program Grant and Fellowship, J.A.V.), and the University of Melbourne (Early Career Researcher Grant, H.E.G.McW.).