The role of cross presentation in viral infection

“交叉呈递”描述了外源性抗原经由I类MHC呈递给CD 8 T细胞。这一机制解释了如何通过对自身抗原的耐受诱导来灭活自身反应性CD 8 T细胞。此外，交叉呈递似乎允许产生针对外源性肿瘤抗原或源自病毒的抗原的细胞毒性T细胞应答，所述外源性肿瘤抗原或源自病毒的抗原可抑制感染的树突状细胞并抑制直接MHC I呈递。虽然几种细胞类型似乎能够交叉呈递抗原，但树突状细胞是最有效的。然而，尽管做出了许多努力，交叉呈递对控制病毒感染和疫苗接种的贡献仍不清楚。使用转基因小鼠与树突状细胞不能交叉表达外源性抗原和单纯疱疹病毒-以及鼠巨细胞病毒-突变体缺乏基因的免疫失活的组合，我们将研究交叉呈递在初级和记忆CD 8 T细胞反应中的作用。这项研究的结果将与免疫系统功能的基本理解以及疫苗的合理设计有关。

“Cross-presentation” describes the presentation of exogenous antigen via MHC class I to CD8 T cells. This mechanism explains how inactivation of self-reactive CD8 T cells by tolerance induction to self-antigen might occur. In addition, cross-presentation seems to allow the generation of cytotoxic T cell responses to exogenous tumour antigens or antigens derived from virus, which can inactivate infected Dendritic Cells and inhibit direct MHC I presentation. Although several cell types seem to be able to cross-present antigens, Dendritic Cells are most potent to do so. However, despite many efforts, the contribution of cross-presentation to control of viral infections and vaccination is still unclear. Using a combination of transgenic mice with dendritic cells unable to crosspresent exogenous antigens and Herpes-Simplex-Virus- as well as Murine Cytomegalovirus-mutants lacking genes contributing to immune inactivation, we will study the role of cross-presentation in primary and memory CD8 T cell responses. The outcome of this study will be relevant for the basic understanding of the functioning of the immune system, as well as the rational design of vaccines.