臺灣博碩士論文加值系統

由C型肝炎病毒感染而引起的C型肝炎已繼B型肝炎之後成為重要肝病的病源，也是肝癌主因之一。目前以干擾素(IFN-α)與核苷酸擬似物Ribavirin之合併治療，對C型肝炎病患有最佳的病毒清除能力。幾個病毒學的因子，包括病毒的基因型、濃度、以及患者的免疫反應均與療效有關。而最近研究病人的免疫反應也被提出為抗病毒反應之ㄧ，其中患者體內的Th1細胞激素的增高，在若干研究中顯示有利於治療後病毒清除。本研究利用干擾素及Ribavirin合併治療C型肝炎患者，探討血清中多個由Th1和Th2細胞所分泌之細胞激素在治療的不同時期對於病毒清除之間關係，試圖找尋利用Th1及Th2細胞激素分泌量來預測病患對未來治療的反應的可能性。
研究對象為17位來自於彰化基督教醫院感染C型肝炎病毒的患者，利用干擾素與Ribavirin之合併治療6個月後繼續追蹤6個月以上。利用Real-time PCR定量，依據C型肝炎病毒濃度的增減，7位患者具持續病毒壓制的效果，7位患者則有復發的狀況和3位對於治療沒有反應。利用ELISA檢測3組不同的治療效果患者在治療前、治療時期和後續追蹤時期血清中細胞激素。
結果顯示，具持續病毒壓制效果的患者在治療時期顯著增加Th1型細胞激素TNF-α，但對於IFN-γ並無顯著增加的趨勢，Th1型細胞激素不同時期都持續高表達，而Th2系列的細胞激素IL-4、IL-6 及IL-10則在治療時期及後續追蹤時期，則維持持平的趨勢。復發組在治療時期及後續追蹤檢查，發現Th2型的細胞激素IL-4、IL-6與Th1型細胞激素IFN-γ有減少的趨勢。沒有治療反應的患者中，發現TNF-α的表現量維持在很低的濃度，而Th2細胞激素的產生則恆定表現。體內的Th1細胞激素表現量的增加，Th2細胞激素維持持平，可使發炎反應適度地增強，以達到抑制病毒擴增之效果。以上結果顯示，透過治療前後細胞激素的型式與量的追蹤，可望提早評估慢性C型肝炎患者對於干擾素和Ribavirin治療之反應性。

As we gaining control of hepatitis B infection, hepatitis C has emerged to be a major concern in dealing with diseases such as liver cirrhosis and hepatocelluar carcinoma. Currently, combined interferon-α and ribavirin therapy offers the best chance for viral clearance in chronic hepatitis C patients. While several virological factors including the viral genotype and titer have been associated with the efficacy of interferon therapy, host immune responses were recently been addressed to codetermine the anti-viral effects. An increase in Th1 cytokines, but not Th2 cytokines generally favors sustained response in interferon/ribavirin therapy. The aims of this study are to monitor serial changes of several major Th1 and Th2 cytokine productions in chronic hepatitis C patients during the course of interferon/ribavirin combined therapy, exploring the possibility of using Th1 and Th2 profile in predicting responses toward therapy.
Seventeen patients with chronic hepatitis C treating with pegylated interferon-α plus ribavirin for a period of 6 months were enrolled in this study. Viral concentrations were determined by reversed transcription followed by real-time PCR. After an additional 6-month follow-up, 7 of 17 patients were classified by viral titer as sustained virological responders (SVR), 7 as relapsed and the other 3 were non-responders. Cytokine productions were accessed by ELISA during pre-treatment, treatment and at end of follow-up.
As shown in the results, the patients with SVR have a significant increase in the production of TNF-α during and after therapy, while levels of IFN-γ, GM-CSF, and Th2 cytokines, i.e. IL-4.IL-6 and IL-10, were basically unchanged. Relapsed patients showed a profound decrease of IFN-, IL-4 and IL-6 during and after therapy, while other cytokines remain at the same level. For the non-responders, TNF-α expression was maintained at a low level, while Th2 cytokine productions were kept the same. The sustained viral response observed in SVR group may attribute largely to a persistent Th1 and controlled Th2 responses. During IFN-α plus ribavirin therapy which controls viral replication in chronic hepatitis C patients, the cytokine pattern of T cells may serve as an indicative role in therapeutic outcome.

中文摘要 ………………………………………………………………… 1
英文摘要 ………………………………………………………………….3
壹、 文獻回顧………………………………………………………….…5
ㄧ、前 言 ………………………………………………………………5
二、C型肝炎之發現…………………………………………………….6
三、C型肝炎之流行病學……………………………………………..10
四、C型肝炎之診斷方式…………………………….……………….12
五、C型肝炎之治療……………………………………….………….13
六、細胞激素…………………………..……………..……………….24
七、C型肝炎與細胞激素的相關性……………....…………………..32
貳、材料與方法 ………………………………………………………...38
ㄧ、研究對象…………………………………………………………..38
二、C型肝炎病毒抽取…………………………………………………38
三、反轉錄…………………………………………………………… 39
四、聚合酶酵素鏈鎖反應…………………………………………….39
五、即時定量聚合酶酵素鏈鎖反應………………………………….40
六、標準曲線的建立…………………………………………………..41
七、質體抽取………………………………………………………….42
八、DNA片段的回收及純化………………………………………….43
九、接合作用…………………………………………………………43
十、Transformation 之competent cell的製備…………………44
十一、基因轉形………………………………………………………44
十二、限制酵素剪切………………………………………………….45
十三、酵素免疫分析法………………………………………………45
十四、統計分析………………………………………………………46
参、結果與討論…………………………………………………………47
一、病人分類以及療效初步分析……………………………………48
二、Th2系列細胞激素之血清量與慢性C型肝炎和長期療效之關連性
分析…………………………………………………………………48
三、Th1系列細胞激素之血清量與慢性C型肝炎和長期療效之關連性
分析…………………………………………………………………51
四、GM-CSF之血清量與慢性C型肝炎和長期療效之關連性分析…54
肆、結論…………………………………………………………………56
圖表………………………………………………………………………58
參考文獻…………………………………………………………………67

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