Bird flu library

Source: Scripps Research Institute

An international group of American and Turkish research scientists, led by Sea Lane Biotechnologies, has created the first comprehensive monoclonal antibody libraries against avian influenza (H5N1) using samples from survivors of the 2005/2006 bird flu outbreak in Turkey.

These antibody libraries hold the promise for developing a therapy that could stop a pandemic in its tracks and provide treatment to those infected, as well as potentially pointing the way towards the development of a universal flu vaccine, Sea Lane said.

"Three global influenza pandemics have occurred within the past 100 years, each with devastating consequences," Professor Richard Lerner, president of the Scripps Research Institute, who collaborated with Sea Lane on a study published in the US Proceedings of the National Academy of Sciences..

"Our study holds out the hope that a new outbreak could potentially be stopped at an early stage, and that effective treatment could be available to those infected."

So far, the new antibody libraries reported in the study have yielded more than 300 unique monoclonal antibodies that are active against H5N1 antigens. From this group, the authors identified several broadly neutralizing antibodies that were effective against a number of contemporary subtypes of H5 (avian) flu.

The new research suggests that the antibodies recovered from the avian flu survivors may point to an exploitable weak spot in the virus, offering the tantalising possibility that a "universal" vaccine against all strains might be made.

Three of the more than 300 antibodies catalogued have been found to neutralize both the H1 (common seasonal flu) and H5 (avian) subtypes.

"The antibodies we have isolated have the potential to be used directly as therapeutic agents against multiple influenza subtypes, permitting the resolution of infection upon administration to an infected individual," another collaborator, Professor Peter Palese of the Mount Sinai School of Medicine in New York, said.

"Perhaps most importantly, these antibodies may be used to identify cross-reactive epitopes on the hemagglutinin protein of an influenza virus. Identification of such epitopes may allow the rational design of vaccines with cross-subtype neutralising activity.

"Such vaccines would constitute a major advance on current technology, and would be a first step towards the design of a universal influenza vaccine."

The antibody libraries were not dependent on whether an important antibody was being produced by the body at the time of the sample collection. Instead, the scientists were able to obtain the entire immunologic history of an individual's response, which offered a clearer picture of the relationships between antibodies and their relative effectiveness.