10/10/06

Opening a new front in the war against flu, researchers at the University of Wisconsin-Madison have reported the discovery of a novel compound that confers broad protection against influenza viruses, including deadly avian influenza.

The new work, reported online October 4, 2006 in the Journal of Virology, describes the discovery of a peptide—a small protein molecule—that effectively blocks the influenza virus from attaching to and entering the cells of its host, thwarting its ability to replicate and infect more cells.

The new finding is important because it could make available a class of new antiviral drugs to prevent and treat influenza at a time when fear of a global pandemic is heightened and available antiviral drugs are losing their potency.

The new drug, which was tested on cells in culture and in mice, conferred complete protection against infection and was highly effective in treating animals in the early stages of infection. Untreated infected animals typically died within a week. All of the infected animals treated with small doses of the drug at the onset of symptoms survived.

The new drug, known as “entry blocker,” is a fragment of a larger human protein whose role in biology is to help things pass through membranes such as those that encapsulate cells.

Although the peptide’s precise mechanism for thwarting flu remains to be deciphered, it seems to work by blocking the virus’ ability to latch onto a key cell surface molecule that the virus uses to get inside cells.