Bird Flu Alarm

2006-01-03-California institute reports on progress towards flu vaccine

Understanding Avian Influenza

2006-01-03-California institute reports on progress towards flu vaccine

Cheroutre's concept focused on M2, a protein common to all influenza A viruses, including avian flu strains. Her insight was to suggest using a portion of the M2 protein to immunize Transchromosomic miceTM, which are mice genetically-engineered to produce human antibodies. The TC MouseTM Technology, developed by Kirin's Pharmaceutical Division, allowed researchers to obtain influenza M2-specific human antibodies.

In conducting the research, Gemini scientists used synthetically created pieces of the H5NI avian flu virus, along with a number of other synthesized virus pieces, to analyze the effectiveness of the human anti-M2 antibodies, which had been created from theTranschromosomic miceTM. "In laboratory (in vitro) testing, they found that the anti-M2 antibodies bound to several different influenza strains, including the avian flu virus (H5N1)," Cheroutre said. "This reactivity means that if used in vivo (in a living organism) the infected cells would be recognized by the antibody and destroyed by the immune system." The study also found that a relatively low dose of the antibodies was needed to fight the various flu strains.

While most of the work was done on virus pieces to avoid the risk of using actual viruses, Gemini also tested the M2 antibodies on mice infected with a potentially lethal influenza strain, with similarities to the avian flu virus. "They found that those mice which received the human M2 antibody were protected, while those mice that did not get the M2 antibody would die," Cheroutre said.

Based upon the lab and mice testing, Gemini Science is now initiating pre-clinical studies required for the commencement of human clinical testing of the anti-M2 antibody, said Shinichiro Kato, Ph.D., Gemini's Chief Scientific Officer. Gemini, which is testing the antibody both as a treatment and preventative measure against flu, has expedited the research due to the recent cases of avian flu. Gemini is currently in discussions with the Centers for Disease Control (CDC) about establishing a Cooperative Research and Development Agreement to jointly conduct further research. Gemini's findings were presented Saturday at the 45th annual Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC), which runs through Monday in Washington, D.C.

Understanding Avian Influenza