Department of Pediatrics, University of Maryland School of Medicine, Baltimore, MD, USA.
Pathog Dis. 2013 Feb;67(1):46-53. doi: 10.1111/2049-632X.12014. Epub 2013 Jan 22.
Dendritic cells (DCs) play an important role as antigen-presenting cells that direct the nature of the adaptive immune response. Subtypes are differentiated by lineage, tissue, marker expression and function. Their function in promoting regulatory T cells in the gut to maintain immunologic homeostasis is well documented, but their role in the Helicobacter pylori-infected stomach is less clear. Some analyses of bone marrow-derived DCs stimulated with H. pylori have demonstrated proinflammatory potential based on secretion of IL-12 or IL-23 or activation of Th1 and Th17 cells. Other analyses indicate that H. pylori-activated DCs are less responsive compared with other gastrointestinal bacteria and activate DCs to promote Treg development. DC depletion in mice supports a role for DCs in down-regulating H. pylori-induced gastritis. These data indicate that gastric DCs recognize H. pylori much like DCs in the gut that recognize commensal organisms and promote a regulatory T-cell response. This is consistent with a growing body of literature documenting the prevalence and function of Treg cells in the host response to H. pylori. Research is now focused on characterizing how H. pylori induces such activity in DCs and identifying the mechanisms by which H. pylori-activated DCs activate Treg cells.
树突状细胞 (DCs) 作为抗原呈递细胞发挥着重要作用，它们决定了适应性免疫反应的性质。亚型通过谱系、组织、标志物表达和功能来区分。它们在促进肠道中调节性 T 细胞以维持免疫稳态方面的作用已得到充分证明，但在幽门螺杆菌感染的胃中的作用尚不清楚。一些分析表明，基于 IL-12 或 IL-23 的分泌或 Th1 和 Th17 细胞的激活，用幽门螺杆菌刺激骨髓来源的 DC 具有促炎潜能。其他分析表明，与其他胃肠道细菌相比，幽门螺杆菌激活的 DCs 的反应性较低，并且激活 DCs 以促进 Treg 发育。在小鼠中耗尽 DC 支持 DC 在下调幽门螺杆菌诱导的胃炎中的作用。这些数据表明，胃 DC 类似于肠道中的 DC 识别共生生物并促进调节性 T 细胞反应，从而识别幽门螺杆菌。这与越来越多的文献一致，这些文献记录了 Treg 细胞在宿主对幽门螺杆菌反应中的普遍性和功能。目前的研究重点是描述幽门螺杆菌如何诱导 DC 产生这种活性，并确定幽门螺杆菌激活的 DC 激活 Treg 细胞的机制。
