Radziewicz Henry, Ibegbu Chris C, Fernandez Marina L, Workowski Kimberly A, Obideen Kamil, Wehbi Mohammad, Hanson Holly L, Steinberg James P, Masopust David, Wherry E John, Altman John D, Rouse Barry T, Freeman Gordon J, Ahmed Rafi, Grakoui Arash
Emory University School of Medicine, 954 Gatewood Road N.E., Atlanta, GA 30329, USA.
J Virol. 2007 Mar;81(6):2545-53. doi: 10.1128/JVI.02021-06. Epub 2006 Dec 20.
The majority of people infected with hepatitis C virus (HCV) fail to generate or maintain a T-cell response effective for viral clearance. Evidence from murine chronic viral infections shows that expression of the coinhibitory molecule PD-1 predicts CD8+ antiviral T-cell exhaustion and may contribute to inadequate pathogen control. To investigate whether human CD8+ T cells express PD-1 and demonstrate a dysfunctional phenotype during chronic HCV infection, peripheral and intrahepatic HCV-specific CD8+ T cells were examined. We found that in chronic HCV infection, peripheral HCV-specific T cells express high levels of PD-1 and that blockade of the PD-1/PD-L1 interaction led to an enhanced proliferative capacity. Importantly, intrahepatic HCV-specific T cells, in contrast to those in the periphery, express not only high levels of PD-1 but also decreased interleukin-7 receptor alpha (CD127), an exhausted phenotype that was HCV antigen specific and compartmentalized to the liver, the site of viral replication.
大多数丙型肝炎病毒(HCV)感染者无法产生或维持有效的T细胞反应以清除病毒。来自小鼠慢性病毒感染的证据表明,共抑制分子PD-1的表达预示着CD8+抗病毒T细胞耗竭,并可能导致病原体控制不足。为了研究人类CD8+ T细胞在慢性HCV感染期间是否表达PD-1并表现出功能失调的表型,我们检测了外周血和肝内HCV特异性CD8+ T细胞。我们发现,在慢性HCV感染中,外周血HCV特异性T细胞表达高水平的PD-1,而阻断PD-1/PD-L1相互作用会导致增殖能力增强。重要的是,与外周血中的T细胞相比,肝内HCV特异性T细胞不仅表达高水平的PD-1,而且白细胞介素-7受体α(CD127)表达降低,这是一种HCV抗原特异性且局限于病毒复制部位肝脏的耗竭表型。