Villadangos J A
The Walter and Eliza Hall Institute of Medical Research, P.O. The Royal Melbourne Hospital, 3050, Victoria, Melbourne, Australia.
Mol Immunol. 2001 Sep;38(5):329-46. doi: 10.1016/s0161-5890(01)00069-4.
The function of MHC class II molecules is to bind peptides derived from antigens that access the endocytic route of antigen presenting cells and display them on the plasma membrane for recognition by CD4(+) T cells. Formation of the MHC II-peptide complexes entails the confluence of the antigens and the MHC II molecules in the same compartments of the endocytic route. There, both the antigens and the MHC II molecules undergo a series of orchestrated changes that involve proteases, other hydrolases and chaperones, culminating in the generation of a wide repertoire of MHC II-peptide combinations. All the events that lead to formation of MHC II-peptide complexes show a considerable degree of flexibility; this lack of strict rules is advantageous in that it provides T cells with the maximum amount of information, ensuring that pathogens do not go undetected.
MHC II类分子的功能是结合源自进入抗原呈递细胞内吞途径的抗原的肽，并将它们展示在质膜上以供CD4(+) T细胞识别。MHC II-肽复合物的形成需要抗原和MHC II分子在内吞途径的同一区室中汇合。在那里，抗原和MHC II分子都会经历一系列精心编排的变化，这些变化涉及蛋白酶、其他水解酶和伴侣蛋白，最终产生大量的MHC II-肽组合。导致MHC II-肽复合物形成的所有事件都表现出相当程度的灵活性；这种缺乏严格规则的情况是有利的，因为它为T细胞提供了最大量的信息，确保病原体不会不被发现。
