慢性C型肝炎病毒基因型第一型患者,接受長效型干擾素及雷巴威林治療體內樹突細胞數目及功能之變化

The Number and Function of Dendritic Cells in Patients with Hepatitis C Virus Genotype 1 Infection Treated with Pegylated Interferon plus Ribavirin

梁程超(Cheng-Chao Liang)

指導教授 ： 高嘉宏

國立臺灣大學/醫學院/臨床醫學研究所/碩士(2009年)

https://doi.org/10.6342/NTU.2009.01370

摘要

研究背景
目前以長效型干擾素合併雷巴威林(ribavirin)來治療慢性C型肝炎患者，約有50-60%可達到持久病毒反應。關於宿主對抗病毒的免疫反應對於治療成效所扮演的角色，至今仍不太清楚。近年來有些研究發現慢性HCV感染的病人其樹突細胞(dendritic cell, DC)的數目、活化T細胞的功能及製造IL-12、IFN-α 和IFN-γ較健康成人差，另外，若是自限性HCV的病人或是經治療後成功清除HCV的病人，其樹突細胞的數目及活化T細胞的功能則和健康成人相近。但深入探討關於治療前、後樹突細胞數目及功能變化與治療療效相關性之研究仍屬有限。
研究目的
探討病毒基因型為第一型的慢性C型肝炎患者接受長效型干擾素及雷巴威林合併治療前、後，病患周邊血液中樹突細胞之數目及功能之變化與治療療效之相關性。
研究方法
本研究為前瞻性研究，基因型為第一型的慢性C型肝炎患者接受長效型干擾素合併雷巴威林為期24週的治療。病患於治療前、治療第4週、第12週、第24週、及停藥後24週檢查C型肝炎血清病毒(HCV RNA)；於治療前及停藥後24週評估樹突細胞數目及功能。樹突細胞功能評估包括檢測樹突細胞的活化表面標記(CD80、CD83、CD86、HLA-DR)、異體淋巴細胞混合反應和樹突細胞分泌細胞激素(IL-5、IL-10、IL-12、 IFN-γ)評估。對照組則尋找性別及年紀相符之健康成人。
我們將比較治療組在治療前、後，樹突細胞的數目及功能與健康對照組之差異；在治療組中我們將依治療結果分成三組，分別是1. 治療成功即有持久病毒反應(SVR) 2. 復發 (relapse) 3. 無反應 (non-response)，比較這三組間樹突細胞的數目及功能之差異，並試圖尋找與治療成效有關之預測因子。
結果
共有20位病患加入本研究，其中15位為男性，年齡為26-62歲；對照組則有10位健康成人。19位病患完成24週之療程，1位病患於第16週因治療療效差而中斷治療；有15位患者達到快速病毒反應(第4週HCV RNA陰性)，在5位第4週HCV RNA仍呈陽性病患中，有3位達到早期病毒反應(第12週HCV RNA陰性)，另2位病患中有1位治療失敗，另1位中斷治療。於本論文撰寫時，有8位病患完成停藥後24週之追蹤，其中5位達到持久病毒反應，3位復發。
慢性C型肝炎患者其治療前周邊血中髓系樹突細胞(myeloid DC, mDC)及胞漿性樹突細胞(plasmacytoid DC, pDC)的量較健康成人為低(mDC 0.2% vs 0.28%, p=0.009; pDC 0.05% vs 0.09%, p=0.004)，但與病毒量多寡或能否達到快速病毒反應無關。慢性C型肝炎患者樹突細胞分化及成熟度與健康成人差不多，但在HCV RNA大於800,000 IU/ml的病患中，CD83成熟度較病毒量低者差；但對於能否達到快速病毒反應則無統計學上的差異。但在5位於第4週HCV RNA仍呈陽性的患者中，有3位樹突細胞的成熟度較其他病患差。至於慢性C型肝炎患者樹突細胞促進T細胞增生的能力雖略低於健康成人，但無統計學上的差異。但在2位無治療反應病患中，其樹突細胞促進T細胞增生的能力明顯較其他病患差。至於樹突細胞分泌細胞激素，健康成人與慢性C型肝炎患者細胞激素的產量無顯著差異，但IL-10的產量在無法達成快速病毒反應的病患非常顯著地高於可以達成快速病毒反應的病患(p<0.001)。
結論
慢性C型肝炎患者周邊血液中mDC及pDC的數量顯著地較健康成人低，但與治療前病毒濃度的高低或治療後能否達成快速病毒反應無顯著差異。慢性C型肝炎患者樹突細胞的分化成熟度、促進T細胞增生的能力及細胞激素的產量與健康成人無顯著差異；但若樹突細胞的功能越差或是細胞激素IL-10的產量越高，則對治療的反應越差。

關鍵字

慢性C型肝炎 ； 樹突細胞

並列摘要

Backgound
The rate of sustained virologic response (SVR) achieved by the combination therapy with pegylated interferon (PEG-IFN) plus ribavirin for patients with hepatitis C virus (HCV) infection has been up to 50-60%. The impact of host immunity on treatment effect remains unclear. Reduced number of dendritic cells (DC) in the peripheral blood with decreased capacity to drive T cell proliferation and cytokines (IL-12, IFN-α and IFN-γ) production has been reported in chronic hepatitis C patients. In addition, the number and capacity of DC to induce T-cell proliferation in self-limited patients and sustained virologic responders are comparable to those in healthy controls. However, little is known about the relationship between changes of number and function of DC before and after anti-viral treatment as well as treatment outcomes.
Aim of this study
The aim of this study is to evaluate the association of number and function of DC with treatment outcomes in patients with HCV genotype 1 infection treated with PEG-IFN plus ribavirin.
Methods
In this prospective study, we enrolled patients with HCV genotype 1 infection treated with PEG-IFN plus ribavirin for 24 weeks. Serum HCV RNA level was determined quantitatively by RT-PCR analysis at baseline, week 4, week 12, end of treatment, and 24 weeks post-treatment. The number and function of DC were assayed at baseline and 24 weeks post-treatment. The functional assays of DC included expression of co-stimulatory molecules (CD80, CD83, CD86, HLA-DR), allogeneic mixed lymphocyte reaction, and cytokines production (IL-5, IL-10, IL-12, IFN-γ). Age and sex-matched healthy adults were served as controls. The treatment outcomes were divided into SVR, relapse, and non-response.
Results
Twenty patients were enrolled in this study, and fifteen were males. The age ranged from 26 to 62 years old. Ten healthy volunteers were enrolled as controls. Nineteen patients completed the 24 weeks of combination therapy. One patient dropped out at week 16 due to poor virologic response. Fifteen patients achieved rapid virologic response (undetectable HCV RNA at week 4). Of 5 patients without RVR, three achieved complete early virologic response (undetectable HCV RNA at week 12). One patient had non-response (detectable HCV RNA at week 24). At the time of this writing, eight patients completed the follow-up and five achieved SVR. The other three patients had relapse.
The numbers of myeloid DC (mDC) and plasmacytoid DC (pDC) in the peripheral blood were significantly lower in patients with chronic hepatitis C than in healthy donors (mDC 0.2% vs 0.28%, p=0.009; pDC 0.05% vs 0.09%, p=0.004) at baseline. The number of DC was not correlated with viral load and RVR. The expression of co-stimulatory molecules was comparable between chronic hepatitis C patients and healthy controls. However, CD83 expression in patients with baseline serum HCV RNA levels > 800,000 IU/ml was lower than those with HCV RNA levels < 800,000 IU/ml. Of 5 patients without RVR, lower expression of co-stimulatory molecules was observed in 3. Although the ability to drive T cell proliferation was not significantly different between chronic hepatitis C patients and healthy controls, 2 patients with non response seemed to have lower ability. In addition, cytokine production of DC in chronic hepatitis C patients was similar to healthy controls. However, IL-10 production was significantly higher in patients without RVR than those with RVR (p<0.001).
Conclusions
The numbers of mDC and pDC in the peripheral blood are significantly lower in chronic hepatitis C patients than healthy controls. However, the number of DC is not correlated with viral load and achievement of RVR in patients treated with PEG-IFN plus ribavirin. The expression of co-stimulatory molecules, ability to drive T cell proliferation, and cytokines production of DC are comparable between chronic hepatitis C patients and healthy controls. Lower expression of co-stimulatory molecules and impaired ability to drive T cell proliferation as well as higher production of IL-10 of DC may imply a poor treatment response in patients with HCV genotype 1 infection treated with PEG-IFN plus ribavirn.

並列關鍵字

Chronic hepatitis C ； Dendritic cells

參考文獻

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