Unidad de Inmunología, Facultad de Medicina, Universidad Complutense, Madrid, Spain.
Biochem Biophys Res Commun. 2011 Aug 5;411(3):632-6. doi: 10.1016/j.bbrc.2011.07.007. Epub 2011 Jul 13.
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.
黏膜相关恒定 T（MAIT）细胞是一类受主要组织相容性复合体相关 1（MR1）分子限制的非常规 T 淋巴细胞。MR1 是 MHC Ⅰ类蛋白家族的非经典成员，目前尚不清楚 MR1 是否向 MAIT 细胞呈递任何抗原。在本研究中，我们描述了在 26°C 培养细胞时，通过构象依赖性单克隆抗体检测到细胞表面的 MR1 增强；我们还表明，在 pH 3.3 下处理细胞后，MR1 在细胞表面的检测丢失，如经典 MHC Ⅰ类分子的情况。最后，细胞表面 MR1 的重新表达与蛋白酶体无关。综上所述，这些结果强烈表明，MR1 需要结合非蛋白酶体依赖性配体才能正确到达细胞表面。
