Center for Comparative Medicine, School of Veterinary Medicine, University of California Davis, Davis, California, United States of America.
PLoS Pathog. 2012 Jan;8(1):e1002499. doi: 10.1371/journal.ppat.1002499. Epub 2012 Jan 19.
Pathogens can substantially alter gene expression within an infected host depending on metabolic or virulence requirements in different tissues, however, the effect of these alterations on host immunity are unclear. Here we visualized multiple CD4 T cell responses to temporally expressed proteins in Salmonella-infected mice. Flagellin-specific CD4 T cells expanded and contracted early, differentiated into Th1 and Th17 lineages, and were enriched in mucosal tissues after oral infection. In contrast, CD4 T cells responding to Salmonella Type-III Secretion System (TTSS) effectors steadily accumulated until bacterial clearance was achieved, primarily differentiated into Th1 cells, and were predominantly detected in systemic tissues. Thus, pathogen regulation of antigen expression plays a major role in orchestrating the expansion, differentiation, and location of antigen-specific CD4 T cells in vivo.
病原体可以根据不同组织中的代谢或毒力需求，在感染宿主中大量改变基因表达，但这些改变对宿主免疫的影响尚不清楚。在这里，我们观察了沙门氏菌感染小鼠中多种 CD4 T 细胞对随时间表达的蛋白的反应。鞭毛蛋白特异性 CD4 T 细胞早期扩增和收缩，分化为 Th1 和 Th17 谱系，并在口服感染后在粘膜组织中富集。相比之下，对沙门氏菌 III 型分泌系统 (TTSS) 效应器产生反应的 CD4 T 细胞在细菌清除之前稳步积累，主要分化为 Th1 细胞，并主要在系统组织中检测到。因此，病原体对抗原表达的调节在体内协调抗原特异性 CD4 T 细胞的扩增、分化和定位中起着主要作用。
