丙型肝炎病毒（HCV）F蛋白（ARFP）是近年來(lái)報(bào)道的HCV核心抗原（core）基因的核糖體讀碼框移蛋白,，其功能尚未充分闡明。上海巴斯德研究所腫瘤病毒研究組鄧強(qiáng)副研究員等與上海瑞金醫(yī)院張欣欣教授合作,，應(yīng)用合成F蛋白15肽對(duì)MHC-II人源化轉(zhuǎn)基因小鼠（HLA-DR1以及HLA-DP4）進(jìn)行免疫篩選，通過(guò)DNA免疫和脾細(xì)胞增殖實(shí)驗(yàn),，鑒定獲得HLA-DR1和-DP4限制的3種F蛋白特異性T細(xì)胞表位,；進(jìn)一步通過(guò)臨床合作研究，應(yīng)用上述鑒定的T細(xì)胞表位,，對(duì)62例慢性丙型肝炎病人外周血淋巴細(xì)胞進(jìn)行體外擴(kuò)增和干擾素γ的細(xì)胞內(nèi)染色分析,，首次證實(shí)HCV慢性感染過(guò)程中存在F特異的CD4+T細(xì)胞應(yīng)答。

相對(duì)于免疫機(jī)能正常小鼠實(shí)驗(yàn)?zāi)Ｐ?，HCV慢性感染病人中F特異的T細(xì)胞應(yīng)答顯著減弱,，反映了病毒持續(xù)性感染過(guò)程中T細(xì)胞功能損傷或耐受的重要特征。研究人員同時(shí)對(duì)慢性丙肝病人中F蛋白特異的抗體應(yīng)答和治療特征進(jìn)行了深入分析,。

該項(xiàng)工作充分體現(xiàn)了上海巴斯德所研究人員與臨床研究人員在醫(yī)學(xué)轉(zhuǎn)化型研究方面的共同努力,。

這一研究發(fā)表在12月6日國(guó)際學(xué)術(shù)期刊PLoS  ONE上。

該課題獲國(guó)家自然科學(xué)基金,、中科院知識(shí)創(chuàng)新工程以及十一五國(guó)家重大科技專項(xiàng)經(jīng)費(fèi)支持,。（生物谷Bioon.com）

生物谷推薦原文出處：

PLoS ONE    doi:10.1371/journal.pone.0014237

Characterization of the Specific CD4+ T Cell Response against the F Protein during Chronic Hepatitis C Virus Infection

De-Yong Gao1,2, Gen-Di Jin1, Bi-Lian Yao1, Dong-Hua Zhang1, Lei-Lei Gu1, Zhi-Meng Lu1, Qiming Gong1, Yu-Chun Lone3, Qiang Deng4*, Xin-Xin Zhang1*

1 Department of Infectious Diseases, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China, 2 Songjiang Hospital Affiliated to Shanghai First People's Hospital, Shanghai Jiaotong University, Shanghai, China, 3 INSERM U 542, H?pital Paul Brousse, Villejuif, France, 4 Unit of Tumor Virology, Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China

Abstract

Background

The hepatitis C virus (HCV) Alternate Reading Frame Protein (ARFP or F protein) presents a double-frame shift product of the HCV core gene. We and others have previously reported that the specific antibodies against the F protein could be raised in the sera of HCV chronically infected patients. However, the specific CD4+ T cell responses against the F protein during HCV infection and the pathological implications remained unclear. In the current study, we screened the MHC class II-presenting epitopes of the F protein through HLA-transgenic mouse models and eventually validated the specific CD4+ T cell responses in HCV chronically infected patients.

Methodology

DNA vaccination in HLA-DR1 and-DP4 transgenic mouse models, proliferation assay to test the F protein specific T cell response, genotyping of Chronic HCV patients and testing the F-peptide stimulated T cell response in the peripheral blood mononuclear cell (PBMC) by in vitro expansion and interferon (IFN)- γ intracellular staining.

Principal Findings

At least three peptides within HCV F protein were identified as HLA-DR or HLA-DP4 presenting epitopes by the proliferation assays in mouse models. Further study with human PBMCs evidenced the specific CD4+ T cell responses against HCV F protein as well in patients chronically infected with HCV.

Conclusion

The current study provided the evidence for the first time that HCV F protein could elicit specific CD4+ T cell response, which may provide an insight into the immunopathogenesis during HCV chronic infection.