Scientists from the University of California, Davis and Nanyang Technological University in Singapore examined a peptide lurking inside the hepatitis C (HCV) virus that can eliminate a wide range of viruses without harming host cells. The study found that the peptide can discriminate the molecular makeup of virus cells and host cells and was effective against many cholesterol-containing viruses such as West Nile, HIV and measles.
"Although there are many antiviral drugs on the market, a common problem is that the virus learns how to evade them, becoming resistant to the drug treatment. There is a growing recognition that new classes of antiviral drugs that target multiple viruses are needed," Atul Parikh, senior author of the study, said in a press release. "Because the HCV-derived peptide appears to meet this need, we reason it targets the Achilles' heel of viruses - a lipid coating or membrane envelope less likely to become resistant to drugs targeting them."
Although it has long been known that HCV contains an antiviral peptide, the development of therapies has been difficult due to a lack of understanding as to why the peptide attacks viral envelopes but not host cell membranes. In order to uncover the answer to this question, the researchers tested the peptide on model lipid membranes with varying chemical and physical compositions. The results showed that cholesterol-rich membranes were particularly susceptible in comparison to cholesterol-free vesicles.
The scientists concluded that due to its targeting of cholesterol-rich membranes, which are present in many viruses, it likely displays broad-spectrum antiviral activity; they plan to continue their investigation into the promising peptide with more complex lipid models.
"Understanding how the drug candidate interacts with these biologically important lipids, we reason, should open the door to deciphering the rich and complex biology of these systems and lead to new opportunities for antiviral strategies," Parikh said. "Studies such as ours provide hope that replacing the old paradigm of 'one-bug, one-drug' with broadly applicable drugs against which viruses cannot develop resistance may become a reality soon."
The findings were published in the Jan. 5 issue of Biophysical Journal.
