内体/囊泡途径
中文名称
通路描述
某些抗原通过囊泡机制被跨呈递，涉及在蛋白酶体依赖和 TAP 不依赖的情况下，在内体 compartment 中生成抗原肽并装载到 MHC-I 分子上。内体中的抗原被猫肽酶 S 和其他蛋白酶加工成抗原肽。这些肽的装载直接发生在早期和晚期内体 compartment。为什么某些抗原仅通过胞质途径跨呈递，而其他使用囊泡途径尚不清楚。可能是因为某些表位无法通过内体蛋白酶解生成，或被完全破坏。或者，抗原的物理形态可能影响其可及性，从而影响其被内体或囊泡途径的访问（Shen et al. 2004）。
英文描述
Endosomal/Vacuolar pathway Some antigens are cross-presented through a vacuolar mechanism that involves generation of antigenic peptides and their loading on to MHC-I molecules within the endosomal compartment in a proteasome and TAP-independent manner. Antigens within the endosome are processed by cathepsin S and other proteases into antigenic peptides. Loading of these peptides onto MHC-I molecules occurs directly within early and late endosomal compartments. Why certain antigens are cross-presented exclusively by the cytosolic pathway while others use the vacuolar pathway is unknown. It may be because some epitopes cannot be generated by endosomal proteolysis, or are completely destroyed. Alternatively, the physical form of the antigen may influence its accessibility to the endosomal or vacuolar pathways (Shen et al. 2004).
所含基因
6 个基因