The company's data were presented by Dr. Joel Haynes, LigoCyte's senior director of vaccine development, at the Tenth Annual Conference on Vaccine Research sponsored by the National Foundation of Infectious Diseases in Baltimore.

The current influenza vaccination strategy involves immunization against hemagglutinin antigens that undergo continuous alteration in circulating influenza virus. Because the annual vaccines have to be manufactured in advance of influenza outbreaks, the unexpected emergence of a new or drifted subtype may result in a substantial reduction in protection.

LigoCyte's data show that immunization with their unique influenza H1N1-VLP formulation resulted in 100% protection against both H1N1 and H3N2 influenza challenge in preclinical studies. LigoCyte has also produced influenza VLPs carrying H3N2 and H5N1 antigens. H5N1 is the avian flu subtype that is currently circulating in bird populations and causing sporadic infections and death in humans.

"There is a great need for a universal influenza vaccine that simplifies manufacturing and delivery while enhancing protection against multiple viral subtypes," said Dr. Robert Bargatze, LigoCyte's chief scientific officer.

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"In particular, we found that it was possible to administer the treatment up to 72 hours after infection. This is particularly important as people who have become infected with the virus do not tend to report to their local healthcare facilities until several days after the onset of illness."

The antibodies were discovered in the laboratory of Professor Antonio Lanzavecchia at the Institute for Research in Biomedicine in Switzerland. The researchers used a new technique that allows them to rapidly reproduce human monoclonal antibodies starting from a small sample of blood.

"We can't say for certain that a pandemic influenza virus will resemble the H5N1 strain that we have been studying or that the monoclonal antibodies generated using our technique will be able to tackle such a virus," says Professor Lanzavecchia. "Nevertheless, we are encouraged by the broad neutralizing activity of these antibodies in the lab and the moderate doses required."

Using administered antibodies has a historical precedent. During the 1918 Spanish H1N1 influenza pandemic, there were multiple reports of physicians administering blood taken from survivors to patients infected with the disease. A recent review suggested that this treatment was associated with a halving in mortality. However, directly administering blood carries a risk of infection with other blood diseases, such as Hepatitis C and HIV.

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