Pulmonary & Critical Care Medicine, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA.
Pulmonary & Critical Care Medicine, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, Portland, OR 97239, USA; Portland VA Medical Center, 3710 SW US Veterans Hospital Road, Portland, OR 97239, USA.
Semin Cell Dev Biol. 2018 Dec;84:58-64. doi: 10.1016/j.semcdb.2017.11.028.
MR1 is a non-classical class I molecule that is highly conserved among mammals. Though discovered in 1995, only recently have MR1 ligands and antigens for MR1-restricted T cells been described. Unlike the traditional class I molecules HLA-A, -B, and -C, little MR1 is on the cell surface. Rather, MR1 resides in discrete intracellular vesicles and the endoplasmic reticulum, and can present non-peptidic small molecules such as those found in the riboflavin biosynthesis pathway. Since mammals do not synthesize riboflavin, MR1 can serve as a sensor of the microbial metabolome and could be key to the early detection of intracellular infection. This review will summarize the current understanding of MR1-dependent antigen presentation.
MR1 是一种非经典的 I 类分子,在哺乳动物中高度保守。尽管它于 1995 年被发现,但直到最近才描述了 MR1 的配体和抗原,以及受 MR1 限制的 T 细胞。与传统的 I 类分子 HLA-A、-B 和 -C 不同,细胞表面的 MR1 很少。相反,MR1 存在于离散的细胞内小泡和内质网中,并且可以呈现非肽类小分子,如在核黄素生物合成途径中发现的那些小分子。由于哺乳动物不能合成核黄素,因此 MR1 可以作为微生物代谢组的传感器,并且可能是检测细胞内感染的早期关键因素。这篇综述将总结目前对依赖于 MR1 的抗原呈递的理解。