Poloso Neil J, Roche Paul A
Experimental Immunology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
Curr Opin Immunol. 2004 Feb;16(1):103-7. doi: 10.1016/j.coi.2003.11.009.
Activation of CD4(+) T cells requires the interaction of multiple T-cell receptors with MHC class II-peptide complexes on the surface of antigen-presenting cells (APCs). Recent studies have shown that MHC class II complexes are clustered in APC plasma membrane microdomains, thereby providing a mechanism for localized concentration of MHC class II-peptide complexes. The integrity of one type of APC membrane microdomain, the lipid raft, is important for antigen presentation to T cells. We propose a model in which the coordinated processes of MHC class II peptide loading and intracellular trafficking enhance T-cell activation by loading specific MHC class II-peptide complexes in discrete lipid raft microdomains.
CD4(+) T细胞的激活需要多个T细胞受体与抗原呈递细胞（APC）表面的MHC II类肽复合物相互作用。最近的研究表明，MHC II类复合物聚集在APC质膜微结构域中，从而为MHC II类肽复合物的局部浓缩提供了一种机制。一种APC膜微结构域——脂筏的完整性对于向T细胞呈递抗原很重要。我们提出了一个模型，其中MHC II类肽加载和细胞内运输的协调过程通过在离散的脂筏微结构域中加载特定的MHC II类肽复合物来增强T细胞的激活。
