Each year, the influenza virus spreads through human populations and causes people to cough, sneeze, and have diffuse body aches. The effects of the “Flu” can be different for each individual that it infects, ranging from mild constitutional symptoms to severe respiratory infection. The influenza virus can also be a devastating and deadly virus causing pandemics throughout the world. Most recently in 2009, the H1N1 influenza virus caused widespread panic and exerted a significant strain upon the healthcare systems of many countries throughout the world. In 1918, the Great Flu Epidemic killed an estimated 50 million people virtually overnight. Each year, the influenza virus kills over 500,000 people throughout the world. In the United States, the influenza virus kills over 36, 000 people and results in over 200,000 hospitalizations annually. Fortunately, the pharmaceutical companies work to develop a flu vaccine that can prevent some of the health consequences of infection with the influenza virus. The virus is highly mutable and thus a new vaccine has to be developed each year. Recently, researchers from the United Kingdom, the Netherlands, and Switzerland lead by Dr. Antonio Lanzavecchia have developed an antibody that neutralizes all 16 subtypes of the Influenza A virus. The results of their research were published online in the journal Science. The researchers used molecular cell biology technology to screen over 100,000 plasma cells from 6 different volunteers who had the flu or were immunized with the flu vaccine. The researchers were able to identify a monoclonal antibody that was able to neutralize influenza viruses from both group 1 and group 2 Influenza A, which included all 16 subtypes. The researchers used this monoclonal antibody, which they termed FI6, to confer passive immunity to mice that were infected with the deadly influenza virus. The FI6 monoclonal antibody was able to save the infected mice from the deadly inoculums of influenza virus when it normally would have killed them. The researchers used x-ray crystallographic methods to determine the structure of the antibody and found that is bound to a conserved epitope in the F subdomain of the hemagglutinin glycoprotein on the surface of the influenza virus. The researchers wrote, “The results of prophylaxis and therapy that we report identify FI6 as the first example of a neutralizing monoclonal antibody for potential use against all influenza A viruses”. The development of a monoclonal antibody that neutralizes all 16 subtypes of the influenza A virus is a very important step toward the development of a single universal vaccine. With this new knowledge, researchers can now work on producing a vaccine that can be used once instead of having to be given every year as the virus mutates. In addition, this antibody can function to impart passive immunity to those individuals infected with the influenza virus that have not been vaccinated during time of pandemics.
Watch the YouTube Video from the Dana Farber Cancer Institute about the use of monoclonal antibodies to treat influenza:
Davide Corti et al. “A Neutralizing Antibody Selected from Plasma Cells That Binds to Group 1 and Group 2 Influenza A Hemagglutinins” Science published online July 28, 2011 DOI: 10.1126/science.1205669