Researchers say they have made a major step towards the development of a universal flu vaccine, after a new immunotherapy approach has shown promise in animal studies, Medical News Today reported. The method involves creating a stronger immune reaction against the flu virus in the body, protecting against more viral strains than the current vaccines do. A new flu vaccine is developed each year in order to offer the most protection against the circulating viruses.  But for the developers, it is usually a race against the clock, as the data they use quickly becomes out of date once it reaches them. Also, there is always the possibility that new flu virus strains will emerge after the vaccine has been created. The development of a universal flu vaccine would eliminate the need for the development of annual flu shots. To test their new approach, researchers from the National Institute of Allergy and Infectious Diseases (NIAID) created a vaccine that utilized a fusion of the protein ferritin, which can assemble itself into tiny nanoparticles, and the protein hemagglutinin (HA), which is found on the surface of the influenza virus.   The protein combination ultimately produced nanoparticles with eight protruding viral spikes, which served as the basis for the vaccine’s antigen – what the immune system responds to when creating antibodies. Through a series of tests on mice and ferrets, the researchers found the vaccine was more effective at boosting immunity against a much wider range of virus strains than the current flu vaccine, including strains they were not testing for. According to the researchers, the vaccine is effective because it prompts the immune system to develop antibodies to the parts of the flu virus that stay the same from strain to strain.  They say the study’s findings, published in the journal Nature, could lead to a universal flu vaccine that protects against numerous strains of the influenza virus. Click for more from Medical News Today.source : http://www.foxnews.com/health/2013/05/23/researchers-move-closer-to-development-universal-flu-vaccine/