title: Human MR1 expression on the cell surface is acid sensitive, proteasome independent and increases after culturing at 26°C.
abstract: Mucosal-associated invariant T (MAIT) cells are a population of non-conventional T-lymphocytes which are restricted by the MHC-related 1 (MR1) molecule. MR1 is a non-classical member of the MHC class I family of proteins, it is unknown if MR1 presents any kind of antigens to MAIT cells. In the present manuscript we describe that detection of MR1 on the cell surface by conformation-dependent monoclonal antibodies is enhanced upon culture the cells at 26°C; we also show that detection of MR1 on the cell surface is lost after treating the cells at pH 3.3 as in the case of classical MHC class I molecules. Finally, the re-expression of MR1 on the cell surface is independent of proteasome. Taken together these results strongly suggest that MR1 needs to bind proteasome-independent ligands in order to properly reach the cell surface.
authors.affiliation: Unidad de Inmunología, Facultad de Medicina, Universidad Complutense, Madrid, Spain.
authors.forename: Beatriz
authors.initials: B
authors.lastname: Abós
authors.forename: Manuel
authors.initials: M
authors.lastname: Gómez Del Moral
authors.forename: Beatriz
authors.initials: B
authors.lastname: Gozalbo-López
authors.forename: Juan
authors.initials: J
authors.lastname: López-Relaño
authors.forename: Vanesa
authors.initials: V
authors.lastname: Viana
authors.forename: Eduardo
authors.initials: E
authors.lastname: Martínez-Naves
mesh_terms: D000143:Acids / Q000378:metabolism* / Q000494:pharmacology; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism*; D003080:Cold Temperature; D015395:Histocompatibility Antigens Class I / Q000096:biosynthesis*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D015778:Minor Histocompatibility Antigens; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism*
chemical_list: D000143:Acids; D015395:Histocompatibility Antigens Class I; C094840:MR1 protein, human; D015778:Minor Histocompatibility Antigens; D046988:Proteasome Endopeptidase Complex