Exosomes from Hepatitis C Infected Patients Contain Replication Competent Viral RNA

Since its first isolation and identification in 1989, Hepatitis C virus (HCV), has caused significant disease burden to humans worldwide. So far, there is no vaccine against HCV, and neutralizing antibody therapies to block receptor–mediated transmission of HCV to liver cells have so far achieved limited therapeutic benefits. This indicates that HCV can transmit infection via receptor-independent mechanisms. Evidence suggests that small host extracellular vesicles (exosomes) can mediate receptor-independent transfer of genetic material between cells, though their role in HCV transmission remains uncertain.

Here, researchers at the University of Massachusetts Medical School found that the HCV virus can utilize host exosomes to transmit infection to naïve liver cells, even in the presence of potent blocking anti-HCV receptor antibody treatments. Additionally, we identified alternative treatment strategies that can block host exosomes from transmitting HCV infection. This study provides novel insights to an alternative mechanism of HCV transmission that can compromise anti-HCV immune therapies and proposes potential therapeutic approaches to block exosome-mediated transmission of HCV infection.