Gap in immune responses determine infection levels to flu exposure

Why do some folks who take every precaution still get the flu, while others never even get the sniffles?
 
It comes down to a person's immune system response to the flu virus, says Alfred Hero, professor at the University of Michigan College of Engineering.

In one of the first known studies of its kind, Hero and colleagues from Duke University Medical Center and the Duke Institute for Genome Sciences & Policy, used genomics to begin to unravel what in our complex genomic data accounts for why some get sick while others don't. The study findings will appear in PLoS Genetics Aug. 25.

Hero's analysis group used several methods, including a pattern recognition algorithm previously developed for satellite imaging of the environment to discover the genomic signatures associated with immune response and flu symptoms.

Using these genomic signatures, researchers compared the responses of previously healthy participants inoculated with the flu, and found significant and complex immune responses in both people who got sick and those who did not.

The gene expression data gets to the heart of how the immune system reacts and orchestrates its response to the flu virus, which dictates whether people get sick.

"We looked at over 22,000 genes in 267 blood samples," said Hero, who is also affiliated with the U-M College of Literature, Science & Arts and the U-M Medical School. "No study of this magnitude has ever been done on human immune response."