Department of Microbiology, Peking University Health Science Center, Beijing 100191, China.
Virol J. 2010 Feb 18;7:40. doi: 10.1186/1743-422X-7-40.
Hepatitis C virus (HCV) is a blood-borne flavivirus that infects many millions of people worldwide. Relatively little is known, however, concerning the stability of HCV and reliable procedures for inactivating this virus.
In the current study, the thermostability of cell culture-derived HCV (HCVcc, JFH-1 strain) under different environmental temperatures (37 degrees C, room temperature, and 4 degrees C) and the ability of heat, UVC light irradiation, and aldehyde and detergent treatments to inactivate HCVcc were evaluated. The infectious titers of treated viral samples were determined by focus-forming unit (FFU) assay using an indirect immunofluorescence assay for HCV NS3 in hepatoma Huh7-25-CD81 cells highly permissive for HCVcc infection. MTT cytotoxicity assay was performed to determine the concentrations of aldehydes or detergents at which they were no longer cytotoxic.
HCVcc in culture medium was found to survive 37 degrees C and room temperature (RT, 25 +/- 2 degrees C) for 2 and 16 days, respectively, while the virus was relatively stable at 4 degrees C without drastic loss of infectivity for at least 6 weeks. HCVcc in culture medium was sensitive to heat and could be inactivated in 8 and 4 min when incubated at 60 degrees C and 65 degrees C, respectively. However, at 56 degrees C, 40 min were required to eliminate HCVcc infectivity. Addition of normal human serum to HCVcc did not significantly alter viral stability at RT or its susceptibility to heat. UVC light irradiation (wavelength = 253.7 nm) with an intensity of 450 microW/cm2 efficiently inactivated HCVcc within 2 min. Exposures to formaldehyde, glutaraldehyde, ionic or nonionic detergents all destroyed HCVcc infectivity effectively, regardless of whether the treatments were conducted in the presence of cell culture medium or human serum.
The results provide quantitative evidence for the potential use of a variety of approaches for inactivating HCV. The ability of HCVcc to survive ambient temperatures warrants precautions in handling and disposing of objects and materials that may have been contaminated with HCV.
丙型肝炎病毒（HCV）是一种血源性黄病毒，感染了全球数百万人。然而，人们对 HCV 的稳定性知之甚少，也没有可靠的方法来灭活这种病毒。
在目前的研究中，评估了不同环境温度（37°C、室温及 4°C）下细胞培养衍生的 HCV（HCVcc，JFH-1 株）的热稳定性，以及热、UVC 光照、醛类和去污剂处理灭活 HCVcc 的能力。用间接免疫荧光法检测 HCV NS3，在高度允许 HCVcc 感染的肝癌 Huh7-25-CD81 细胞中，用空斑形成单位（FFU）测定处理后病毒样本的感染滴度。进行 MTT 细胞毒性测定以确定醛类或去污剂的浓度，在该浓度下它们不再具有细胞毒性。
培养中的 HCVcc 在 37°C 和室温（25±2°C）下分别存活 2 天和 16 天，而在 4°C 下病毒相对稳定，至少 6 周内感染性无明显下降。培养中的 HCVcc 对热敏感，在 60°C 和 65°C 孵育分别 8 分钟和 4 分钟即可灭活。然而，在 56°C 时需要 40 分钟才能消除 HCVcc 的感染性。在 RT 时，正常人体血清的加入并未显著改变 HCVcc 的稳定性或其对热的敏感性。在 2 分钟内，强度为 450 μW/cm2 的 UVC 光照（波长=253.7nm）有效地灭活了 HCVcc。醛类、戊二醛、离子型或非离子型去污剂的暴露均可有效地破坏 HCVcc 的感染性，无论处理是在细胞培养基还是人血清存在的情况下进行。
这些结果为各种灭活 HCV 的方法的实际应用提供了定量证据。HCVcc 在环境温度下的存活能力需要在处理和处置可能被 HCV 污染的物体和材料时采取预防措施。
