May 22, 2012
Swine Flu Vaccine Found To Give Broader Flu Protection
Connie K. Ho for RedOrbit.com
With temperatures rising and summer rapidly approaching, flu season may seem long gone. However, this is not so for a group of researchers who have discovered that the pandemic 2009 H1N1 vaccination, otherwise known as the swine flu vaccine, can produce antibodies against a variety of flu strains like H5N1 and H3N2. This new finding highlights a new dimension to the report last year that people who were infected by the pandemic 2009 H1N1 virus could produce high levels of antibodies that were cross-reactive against a broad spectrum of flu strains.
The results come from a collaborative project by researchers from Emory University, the University of Chicago, and the National Institute of Allergy and Infectious Diseases (NIAID) of the National Institutes of Health (NIH).
The progress in the research, published in this week´s edition of the Proceedings of the National Academy of Sciences, assists scientists in their work to create a pan-influenza vaccine that can activate cross-creative antibodies at high levels to shield against various influenza subtypes.
"Since discovering last year that people infected with the H1N1 2009 virus produced antibodies against multiple flu strains, our goal has been to test this ability in vaccinated individuals," commented senior author Dr. Rafi Ahmed, the director of the Emory Vaccine Center and a Georgia Research Alliance Eminent Scholar, in a prepared statement. "Our new finding is a key step in the development of a vaccine that can produce high levels of antibodies that protect against multiple flu strains, including challenging mutations that have the potential for widespread illness and death.”
A virus is made up of a “head” region that undergoes various changes, depending on the strains, and a “stalk” that stays somewhat constant. Generally, antibodies that work against the flu bind themselves to the head of the virus. As a result, seasonal flu vaccines are specific in the way that their protection is designed.
Scientists looked at 24 healthy adults who were immunized with the inactivated pandemic 2009 H1N1 vaccine and B cell (antibody) responses they had. The team saw that the vaccination initiated a quick increase in production of monoclonal antibodies that could neutralize a number of the flu strains. Three of the antibody types stuck to the “stalk” part of the virus, which doesn´t adjust as much as other regions.
The researchers believe that these antibodies could become the foundation for a vaccine that has stronger, more consistent protection. The project also demonstrated that antibodies that can fight multiple strains of influenza aren´t normally seen in people after they´re infected or vaccinated by the seasonal flu. In the study, the scientists saw that the majority of flu antibodies neutralized more than one influenza strain. This strength in neutralization could have been the result of B-cell memory from previous exposure to other flu strains.
"The study is encouraging, that we're seeing antibodies generated against the conserved portions of the virus," explained Dr. Bruce Lee, an associate professor at the University Of Pittsburgh Graduate School Of Public Health, in an MSNBC article. "But it's just an initial step,"
The group will continue with its research by improving on their results and designing a vaccine that can produce a large number of antibodies that can consistently fight against a variety of flu subtypes.