Lau G K, Davis G L, Wu S P, Gish R G, Balart L A, Lau J Y
Department of Medicine, University of Florida, Gainesville, USA.
Hepatology. 1996 Jun;23(6):1318-23. doi: 10.1002/hep.510230604.
Hepatitis C virus (HCV) replicates at a low rate and this makes its detection and intrahepatic localization difficult. To evaluate the clinical implications and effect of interferon alfa (IFN-alpha) therapy on hepatic expression of HCV RNA, HCV RNA was detected by in situ reverse-transcription polymerase chain reaction (IS-RT-PCR) in formalin-fixed paraffin-embedded liver sections from 26 patients with chronic hepatitis C. Results were compared with RT-PCR of HCV RNA extracted from liver sections/tissue. Twenty-four paired post-IFN-alpha treatment biopsy specimens were also assessed. Using RT-PCR of the extracted RNA as a positive standard and non-HCV liver sections as the negative standard, the sensitivity and specificity of IS-RT-PCR were 69% and 100%, respectively. HCV RNA was detected in the cytoplasm of hepatocytes (median, 5% hepatocytes positive; range, 0 to 35%) and very occasionally in infiltrating mononuclear cells. There was no correlation between hepatic expression of HCV RNA and the clinical, biochemical parameters, total and activity scores of histology activity index. Presence of HCV RNA in liver as detected by IS-RT-PCR was associated with higher serum HCV RNA levels (4.9 x 10(6) vs. 0.4 x 10(6) genome Eq/mL, P < .01). There was no difference in the pretreatment proportion of HCV RNA-positive hepatocytes among patients with different biochemical responses to IFN-alpha therapy. In the posttreatment samples, HCV RNA was undetectable by IS-RT-PCR in 16 of 24 patients (P < .01), including all 4 patients who had complete and sustained response (SR). We conclude that HCV RNA was detected by IS-RT-PCR in 0 to 35% of hepatocytes in patients with chronic HCV infection, detection of HCV RNA in liver by IS-RT-PCR was associated with higher viremia levels and IFN-alpha therapy reduced hepatocytic expression of HCV RNA.
丙型肝炎病毒（HCV）复制率低，这使得其检测及肝内定位困难。为评估干扰素α（IFN-α）治疗对HCV RNA肝内表达的临床意义及效果，采用原位逆转录聚合酶链反应（IS-RT-PCR）检测了26例慢性丙型肝炎患者福尔马林固定石蜡包埋肝组织切片中的HCV RNA。将结果与从肝组织切片/组织中提取的HCV RNA的逆转录聚合酶链反应（RT-PCR）结果进行比较。还评估了24例IFN-α治疗后的配对活检标本。以提取RNA的RT-PCR作为阳性标准，非HCV肝组织切片作为阴性标准，IS-RT-PCR的敏感性和特异性分别为69%和100%。在肝细胞胞质中检测到HCV RNA（中位数为5%的肝细胞阳性；范围为0至35%），偶尔在浸润的单核细胞中也能检测到。HCV RNA的肝内表达与临床、生化参数、组织学活动指数的总分及活动评分之间无相关性。IS-RT-PCR检测到的肝内HCV RNA与较高的血清HCV RNA水平相关（4.9×10⁶对0.4×10⁶基因组当量/mL，P<.01）。对IFN-α治疗有不同生化反应的患者，治疗前HCV RNA阳性肝细胞的比例无差异。在治疗后的样本中，24例患者中有16例IS-RT-PCR检测不到HCV RNA（P<.01），包括所有4例获得完全持续应答（SR）的患者。我们得出结论，慢性HCV感染患者中，IS-RT-PCR在0至35%的肝细胞中检测到HCV RNA，IS-RT-PCR检测到肝内HCV RNA与较高的病毒血症水平相关，IFN-α治疗可降低HCV RNA的肝细胞表达。
