Monday, November 6, 2017
New Methods Needed for Growing Influenza Strains
The common practice of growing influenza viruses in chicken eggs has been found to be ineffective for human vaccinations. Scientists at The Scripps Research Institute studied H3N2, an influenza variant virus, in injected chicken eggs and discovered that there was a mutation in the hemagglutinin glycoprotein (HA), which binds the virus to cells. Why did this mutation occur? The virus needed to adapt to the chicken egg environment in order to survive and grow, therefore the virus created mutations- one of which being the L194P mutation in the HA. The L194P mutation changed a key protein that would bind more efficiently to bird cell receptors instead human cell receptors. Vaccine production companies were using the mutated version of the H3N2 virus in their products which ultimately proved to be 33 percent effective against the H3N2 virus.
This study shows the synergistic relationship between the environment and genetics. In our intro biology classes, we mostly learn about Mendelian genetics that is more clear cut and predictable, however real life problems can never be solved by a simple punnet square. This chicken egg study proves exactly why many other factors, such as the environment, can also influence genetics. Both genetics and the environment amplified the effects on human immunology in this study. I think it will be really interesting to see what and how scientists decide is the next best mammalian model to grow strains in.