Department of Microbiology, Peking University Health Science Center, 100191, Beijing, China.
Arch Virol. 2010 May;155(5):627-34. doi: 10.1007/s00705-010-0626-z. Epub 2010 Mar 5.
Attenuated CD4+ T-cell-mediated immune responses are involved in persistence of HCV infection, but the mechanism remains undefined. In this study, the proportions of CD4+ T cell subsets, naïve, central memory, effector memory and effector cells, along with CD25 (IL-2R alpha) and CD127 (IL-7R alpha) expression on different CD4+ T cell subsets, were measured by polychromatic flow cytometry in 24 chronic HCV-infected individuals and 21 healthy controls. A significant decrease in naïve CD4+ T cells and an increase of central memory and effector memory CD4+ T cells were found in HCV-infected patients compared with healthy controls. HCV-infected patients showed a lower level of CD127 expression in all CD4+ T cells subsets, especially in central memory and effector CD4+ T cells. In terms of total CD4+ T cells, an increase in CD25+ regular T cells (CD4+ CD25+ CD127lo) was found in HCV-infected patients. Interestingly, naïve CD4+ T cells showed increased CD25 expression, while effector memory and effector CD4+ T cells had lower CD25 expression. These data indicated that variations in different fractions of CD4+ T cells, including the phenotypic profile and expression level of CD25 and CD127, may be associated with low efficiency of immune response in chronic HCV infection. These results will strengthen the understanding of pathogenesis and dysfunction of CD4+ T cell immunity during long-term HCV persistence.
CD4+ T 细胞介导的免疫应答减弱与 HCV 感染的持续存在有关，但具体机制尚不清楚。在这项研究中，通过多色流式细胞术检测了 24 例慢性 HCV 感染者和 21 例健康对照者不同 CD4+ T 细胞亚群中幼稚 CD4+ T 细胞、中央记忆 CD4+ T 细胞、效应记忆 CD4+ T 细胞和效应细胞的比例，以及 CD25（IL-2R alpha）和 CD127（IL-7R alpha）在不同 CD4+ T 细胞亚群上的表达。与健康对照组相比，HCV 感染者幼稚 CD4+ T 细胞数量减少，中央记忆和效应记忆 CD4+ T 细胞增加。HCV 感染者所有 CD4+ T 细胞亚群的 CD127 表达水平均较低，尤其是中央记忆和效应 CD4+ T 细胞。就总 CD4+ T 细胞而言，HCV 感染者的 CD25+常规 T 细胞（CD4+ CD25+ CD127lo）增加。有趣的是，幼稚 CD4+ T 细胞的 CD25 表达增加，而效应记忆和效应 CD4+ T 细胞的 CD25 表达降低。这些数据表明，不同 CD4+ T 细胞亚群的变化，包括 CD25 和 CD127 的表型特征和表达水平，可能与慢性 HCV 感染中免疫应答效率低下有关。这些结果将加强对慢性 HCV 持续感染期间 CD4+ T 细胞免疫发病机制和功能障碍的理解。
