To create a mouse that’s susceptible to hepatitis C, you have to humanize it first.
Researchers have created the first ever mouse model for the viral infection that used to occur only in humans and chimps.
Mice are resistant to the hepatitis C virus (HCV) infection, but such a rodent model would make it possible to evaluate potential vaccines and drugs in ways we can't right now.
HCV uses specialized molecules found only in us two organisms – a specificity that’s made it hard to development treatments. The virus puts 170 million people around the world at a heightened risk of cirrhosis, liver failure, and cancer.
So Alexander Ploss from Rockefeller University and colleagues introduced human factors that are necessary to encourage HCV uptake into mice.
To trick mouse cells into granting entry for HCV, Nature News explains, the team delivered the genes for human entry factors into their cells using modified adenoviruses – common cold viruses.
The mouse models they created still have functional immune systems. That’s a huge development because previously, researchers have only humanized mice by making them immunodeficient – that is, without fully functioning immune systems (this creates a whole set of other problems).
Now, these immunocompetent mice can express 2 human genes that make them susceptible to HCV.
Unfortunately, we can’t start testing therapeutics on them just yet. This mouse model doesn’t enable a complete virus replication cycle:
In working to overcome this expected limitation in mice with functioning immune systems, the authors created a sensitive detection system. As soon as the virus enters a cell – before it starts to replicate – it triggers the expression of a reporter gene that can be detected by luminescence.
Ploss says that, without the reporter system, they couldn't have made the progress they did. The team’s hoping to make a more robust mouse model by achieving full viral replication.
Though there’s a lot of finessing needed, these genetically humanized mouse models will pave the way for many of the antiviral strategies we still need.
Just last month, the Food and Drug Administration approved hepatitis C therapies, the first targeted ones that sustained viral suppression.
The study was published in Nature today. Via Nature News.
Image of lab mouse via Wiki
This post was originally published on Smartplanet.com