Healey C J, Read S
Addenbrooke's Hospital, Cambridge, UK.
Methods Mol Med. 1998;16:301-7. doi: 10.1385/0-89603-499-2:301.
The hepatitis C virus (HCV) is an orgainsm of the age of molecular biology, for its discovery and much of the research into the infection have relied heavily on molecular techniques. The development of molecular cloning enabled a successful strategy that finally identified HCV (1)as the cause of 90% of posttransfusion (2)and > 50% of sporadic non-A, non-B hepatitis (3) after the failure by immunological techniques to discover the responsible agent. It is an important infection as most infected patients developed chronic hepatitis (> 50%) that can progress to cirrhosis and hepatocellular carcinoma (4-6) . Following the identification of the viral genome, antibody tests were developed which could detect exposure to the virus (7). The presence of antibodies to HCV, however, does not distinguish between those with chronic infection and those who had cleared the virus. Chronic HCV infection can be difficult to diagnose as patients may be asymptomatic and have normal liver biochemistry (8),(9) despite abnormal liver histology. Therefore, demonstration of virus RNA (usually from serum samples) is often necessary to confirm Infection. Detection of HCV RNA requires the sensitivity of nucleic acid amplification (e.g., the polymerase chain reaction) as circulating levels of vnus RNA can be very low (10),(11). Such tests are now widely used to confirm infection, monitor the response to anti-viral therapy, and in epidemiological studies of HCV infection.
丙型肝炎病毒（HCV）是分子生物学时代的一种病原体，因为其发现以及对该感染的许多研究都严重依赖分子技术。分子克隆技术的发展促成了一项成功策略，最终确定HCV（1）是90%的输血后肝炎（2）以及超过50%的散发性非甲非乙型肝炎（3）的病因，此前免疫技术未能找到致病因子。这是一种重要的感染，因为大多数受感染患者会发展为慢性肝炎（>50%），进而可能发展为肝硬化和肝细胞癌（4 - 6）。在确定病毒基因组后，开发了抗体检测方法，可检测病毒暴露情况（7）。然而，HCV抗体的存在并不能区分慢性感染者和已清除病毒者。慢性HCV感染可能难以诊断，因为患者可能无症状且肝脏生化指标正常（8）、（9），尽管肝脏组织学异常。因此，通常需要检测病毒RNA（通常从血清样本中检测）来确诊感染。检测HCV RNA需要核酸扩增的灵敏度（例如聚合酶链反应），因为病毒RNA的循环水平可能非常低（10）、（11）。此类检测现在广泛用于确诊感染、监测抗病毒治疗反应以及HCV感染的流行病学研究。
