As manufacturers work furiously to make a vaccine to protect against 2009 influenza A (H1N1) virus, a Rice University bioengineer is trying to improve the process for future flu seasons. The goal is to shorten the time it takes to identify targeted flu strains and manufacture the vaccines for them.
In a paper published this summer in the journal Protein Engineering, Design & Selection, Rice researchers described a new method to predict the efficacy of H1N1 vaccines.
Michael Deem, Rice's John W. Cox Professor in Biochemical and Genetic Engineering and professor of physics and astronomy, and his group are using a formula they developed several years ago to more accurately predict which vaccines can halt ever-evolving strains of the flu, including the novel H1N1 variety that the World Health Organization has tagged as a pandemic virus.
Deem has identified the dominant epitope regions of hemagglutinin, a part of the virus that the immune system recognizes, as the best candidates for comparison by the formula. Epitopes are antigens, short for antibody generators. They're bits of viral protein the body recognizes when the flu attacks, and they prompt the immune system to make antibodies, destroy the virus and be on guard against future infection by the same microorganism.
Deem's technique compares amino-acid sequences of the epitope regions of two strains of H1N1 -- or any other influenza A virus -- and marks the differences. The fewer the differences, the more likely it is that one strain engineered into a vaccine will help prevent the other from infecting a person.
Vaccines work by introducing weak versions of live or inactivated viruses into the body and give the immune system fair warning that a flu virus with a particular epitope may attack. If a vaccine's epitopes are a perfect match to those of the virus, it should be effective in stopping the flu.
That does not always happen.
|Contact: David Ruth|