Mechanisms of Interferon Action and Resistance in Hepatitis C Virus Infection

干扰素在丙型肝炎病毒感染中的作用和抵抗机制

• 批准号: 7593665
• 负责人: T. Jake Liang
• 金额: $ 50.13万
• 依托单位: NATIONAL INSTITUTE OF DIABETES AND DIGESTIVE AND KIDNEY DISEASES
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/7593665
• 关键词: Animals; Biopsy; Biopsy Specimen; Chronic Hepatitis C; Clinical; Combined Modality Therapy; Consensus; Control Groups; Cytokine Inducible SH2-Containing Protein; Data; Defect; Dose; Drops; Future; Gene Expression; Gene Expression Profiling; Genes; Hepatic; Hepatic Stellate Cell; Hepatitis C; Hepatitis C virus; Hour; Human; In Vitro; Interferon-alpha; Interferons; Interleukin-6; Liver; Mediating; Microarray Analysis; Modeling; Molecular; Outcome; Pan Genus; Pan troglodytes; Pathway interactions; Patients; Peripheral Blood Mononuclear Cell; RNA; Resistance; Ribavirin; Signal Transduction; Transcriptional Activation; Up-Regulation; Week; base; gene induction; gene repression; improved; in vivo; inhibitor/antagonist; insight; novel; peginterferon alfa-2a; response

To understand IFN resistance in vivo, we examined the dynamic responses to human IFN (hIFN)-alfa, -gamma and consensus IFN in the chimpanzee model. In vitro study with peripheral blood mononuclear cells (PBMCs) of naive chimpanzees and healthy human donors showed that chimpanzee responded less well than human to hIFNs. Naive and HCV-infected chimpanzees were treated with hIFNs using higher doses to compensate for the lower efficacy of hIFNs in chimpanzees. The in vivo responses of PBMCs to all three IFNs were much lower in the HCV-infected chimpanzees than those in the naive chimpanzees. The difference was more dramatic in the liver as the hepatic IFN-induced gene inductions were barely detectable in the infected animals. Assessment of various IFN signaling inhibitors showed that following IFN administration, the expression of suppressor of cytokine signaling 3 (SOCS3) was significantly upregulated, possibly through the induction of IL-6, in the liver of HCV-infected chimpanzees. In conclusion, these data indicate a defective response, particularly in the liver, to IFNs in HCV-infected chimpanzees, and this defect is possibly mediated through the activation of SOCS3. Further study on the inhibitory mechanism of IFN effector pathway by HCV infection in chimpanzee may provide novel insights into the clinical issue of nonresponse to IFN therapy. To further explore the mechanisms of IFN action and resistance in HCV patients, we compared hepatic gene expression in patients prior to and during peginterferon and ribavirin therapy. In the on-treatment group patients received either peginterferon alfa-2a alone or ribavirin for 72 hours and peginterferon-alfa 24 hours prior to biopsy. Patients were grouped into rapid responders (RR) with >2-log drop and slow responders (SR) with <2-log drop in HCV RNA by week 4. Pre-treatment biopsy specimens were obtained from a matched control group. Pre-treatment patients were grouped as RR or SR based on subsequent treatment response. Gene expression profiling was performed using Affymetrix microarray technology. Known ISGs were induced in treated patients. In the pre-treatment group, future slow responders (SR) had higher pretreatment ISG expression than rapid responders (RR). On treatment, RR and SR had similar absolute ISG expression but when corrected for baseline expression using the pre-treatment group, RR had marked induction of ISGs while SR showed up-regulation of IFN-inhibitory pathways. Patients pretreated with ribavirin had heightened induction of IFN-related genes as well as down-regulation of genes involved in IFN-inhibition and hepatic stellate cell (HSC) activation. These data suggest that ISG inducibility is important for treatment response and ribavirin may improve outcomes by enhancing hepatic gene responses to peginterferon. Collectively these mechanisms may provide a molecular basis for the improved efficacy of combination therapy.

为了了解体内的IFN抗性，我们检查了对黑猩猩模型中人类IFN（HIFN）-Alfa，-gamma和IFN的动态响应。对黑猩猩和健康的人类捐助者的外周血单核细胞（PBMC）的体外研究表明，黑猩猩对HIFN的反应良好。使用较高剂量的HIFN处理幼稚和HCV感染的黑猩猩，以补偿黑猩猩在黑猩猩中HIFN的较低疗效。在HCV感染的黑猩猩中，PBMC对所有三个IFN的体内反应都比天真的黑猩猩中的体内响应要低得多。由于肝IFN诱导的基因诱导在感染动物中几乎无法检测到肝脏中的差异。对各种IFN信号抑制剂的评估表明，在IFN施用后，细胞因子信号3（SOCS3）的抑制剂的表达显着上调，可能是通过诱导IL-6在HCV感染的黑猩猩的肝脏中的诱导。总之，这些数据表明对HCV感染的黑猩猩中的IFN的反应，特别是在肝脏中的有缺陷，并且该缺陷可能是通过激活SOCS3介导的。进一步研究黑猩猩中HCV感染的IFN效应途径的抑制作用机制可能会提供对IFN治疗无反应的临床问题的新见解。 为了进一步探索HCV患者IFN作用和抗性的机制，我们比较了PEGINTERFERON和RIBAVIRIN疗法之前和期间患者的肝基因表达。在治疗组中，患者单独接受Peginterferon alfa-2a或利巴韦林，在活检前24小时接受Peginterferon-Alfa。在第4周之前，将患者分为> 2-log降低和缓慢反应者（SR）的快速反应者（RR）。根据随后的治疗反应将治疗前患者分为RR或SR。使用Affymetrix微阵列技术进行基因表达分析。在治疗的患者中诱导已知的ISG。在预处理组中，未来的慢速响应者（SR）具有比快速响应者（RR）更高的预处理ISG表达。在治疗时，RR和SR具有相似的绝对ISG表达，但是当使用预处理组校正基线表达时，RR显着诱导ISG，而SR则表现出对IFN抑制途径的上调。利巴韦林预处理的患者增加了IFN相关基因的诱导以及与IFN抑制和肝星状细胞（HSC）激活有关的基因下调。这些数据表明，ISG诱导性对于治疗反应很重要，而利巴韦林可以通过增强对Peginterferon的肝基因反应来改善预后。这些机制总的来说可以为提高组合疗法的疗效提供分子基础。