Aix Marseille Université, CNRS, INSERM, CIML, 13288 Marseille Cedex 9, France.
Institute for Research in Biomedicine (IBiMed) and Ilidio Pinho Foundation, Department of Medical Sciences, University of Aveiro, 3810-193 Aveiro, Portugal.
Mol Immunol. 2018 Jul;99:163-170. doi: 10.1016/j.molimm.2018.05.009. Epub 2018 May 19.
Major histocompatibility complex (MHC) molecules present peptide antigens to T lymphocytes and initiate immune responses. The peptides loaded onto MHC class I or MHC class II molecules can be derived from cytosolic proteins, both self and foreign. A variety of cellular processes, including endocytosis, vesicle trafficking, and autophagy, play critical roles in presentation of these antigens. We discuss the role of autophagy, a major intracellular degradation system that delivers cytoplasmic constituents to lysosomes in both MHC class I and II-restricted antigen presentation. We propose the new term "Type 2 cross-presentation" (CP2) to define the autophagy-dependent processes leading to MHC II-restricted presentation of intracellular antigens by professional antigen presenting cells. A better understanding of Type 2 cross-presentation may guide future efforts to control the immune system through autophagy manipulation.
主要组织相容性复合体 (MHC) 分子将肽抗原呈递给 T 淋巴细胞并启动免疫反应。加载到 MHC I 类或 MHC II 类分子上的肽可以来自胞质蛋白，包括自身和外来蛋白。多种细胞过程，包括内吞作用、囊泡运输和自噬，在这些抗原的呈递中发挥关键作用。我们讨论了自噬的作用，自噬是一种主要的细胞内降解系统，可将细胞质成分递送至溶酶体，在 MHC I 和 II 类限制的抗原呈递中发挥作用。我们提出了“2 型交叉呈递”（CP2）的新概念，以定义导致专业抗原呈递细胞通过 MHC II 类限制呈递细胞内抗原的自噬依赖性过程。更好地理解 2 型交叉呈递可能会指导通过自噬操纵来控制免疫系统的未来努力。
