Hepatitis C virus (HCV) is common among intravenous drug users, with 70 to 80% of abusers infected in the United States. This high association has peaked interest in determining the effects of drug abuse, specifically opiates, on progression of the disease. The discovery of such an association would impact treatment of both HCV infection and drug abuse.
Dr. Wen-Zhe Ho has been interested in such interplay for some time. His laboratory has previously shown using cell culture that morphine enhances virus replication and inhibits IFN-alpha (a natural anti-viral factor produced by immune, as well as host cells, and the only one approved in recombinant form for treating HCV infection). To further these results, his lab has used a cell model system to determine the consequences of morphine withdrawal, which is a common recurring event in opioid users.
Chuan-Qing Wang and colleagues examined the effects of morphine withdrawal (MW) on HCV-infected cultured liver cells by exposing cells to the drug for four days followed by its removal. They also assessed the effects of using naloxone, to block the opioid receptors, in conjunction with drug removal, i.e. precipitated morphine withdrawal (PW). To measure HCV replication, they used a virus-like replicon that mimics the events that occur in liver cells and expression of viral RNA and proteins that HCV uses. Although the replicon does not produce the infectious virus, the HCV replicon system represents the best available system for examining the impact of opiates on HCV at the time of their research study. <
Source:American Journal of Pathology