树突状细胞在慢性乙型肝炎中的免疫功能状态

乙肝病毒(HBV)的清除依赖于强大的、多克隆的、特异的CD8+细胞毒性T细胞和CD4+T辅助细胞来对抗病毒表面抗原、核心抗原和P蛋白抗原。而且,效应T细胞通过分泌淋巴因子能够中止病毒复制而不损伤感染的肝脏细胞,这些效应T细胞需要APC用提呈的抗原、MHC分子、共刺激分子共同激活,树突状细胞(DC)表达MHC1类和2类分子,并能够在摄取抗原后上调细胞膜上的共刺激分子(CD40、CD80、CD86),只有DC能直接使初始型T细胞活化,促进Th1和Th2细胞分化,增强CTL细胞功能。有研究认为长期慢性的乙肝感染与不足的CTL细胞以及TH细胞分化比例不同有关,而这些情况均可能与DC功能损伤有关。

DC In the Chronic Hepotitis B of Immunity Function Appearance

The elimination of HBV depend on the strong,multiclone,special CD~ 8+ cell toxicity T cells and CD~ 4+ helper T cells to antagonize the surfaceantigen of virus,core antigen and P protein antigen .Furthurmore,effective T cells can stop the replication of virus through excreting lymph gene but not damaging infectious liver cells, the activation of these effective T cells need the presented antigen of APC,MHC molecules together with stimulated molecules.DC express MHC 1 and MHC 2, and ascending up the stimulated molecules of cell membrane after taking in antigen.Only DC can activate the naive T cells and promote the differentiation of Th_1 and Th_2and build up the function of CTL.Some research think the long chronic infection of Hepatits B is relataed with the deficient CTL and the different differentiation ratio of TH cells,all of the status is related with the damaged function of DC.