Rapid Assay Predicts Response to Flu Vaccine

An assay predicts, within a few days, whether an individual will produce high levels of antibodies against an influenza vaccine.

Scientists scanned the extent to which selected genes are turned on in white blood cells and predicted, on day three, with up to 90% accuracy, who would make high levels of antibodies against a standard flu vaccine four weeks later.

The approach, which involved immunology, genomics, and bioinformatics, was pioneered by Bali Pulendran, PhD, professor of pathology and laboratory medicine at Emory University School of Medicine (Atlanta, GA, USA) and Yerkes National Primate Research Center (Atlanta, GA, USA) when studying the yellow fever vaccine. He worked with colleagues from the Georgia Institute of Technology (Atlanta, GA, USA), Duke University (Durham, NC, USA), Dana Farber Cancer Institute, Institute for Systems Biology (Boston, MA, USA) and the National Institute of Allergy and Infectious Diseases (Bethesda, MD, USA) to extend this approach to the influenza vaccine, against which many people have some preexisting immunity.

Prof. Pulendran was senior author of a paper reporting the results of the flu vaccine study that were published online on July 10, 2011, in the journal Nature Immunology.

The predictive model is based on a series of clinical studies during the annual flu seasons in 2007, 2008, and 2009. Healthy young adults were vaccinated with a standard flu shot (trivalent inactive vaccine). Others were given live attenuated vaccine nasally.

The activity levels of all human genes were surveyed in blood samples from the volunteers. The activity of many genes involved in innate immunity, interferon, and reactive oxygen species signaling changed after flu vaccination. The team also identified genes in the unfolded protein response, necessary for cells to adapt to the stress of producing high levels of antibodies.

A computer model was developed using the gene activity data from one season to identify small groups of genes that can predict high and low responders. Later, the scientists examined whether the model could forecast who would be high or low responders in two other flu seasons.

"The main goal of our study was to demonstrate the feasibility of predicting how strongly a vaccine will stimulate the immune system," said Prof. Pulendran "Along the way, we have developed an assay that focuses on a handful of genes, which could be the basis for a customized vaccine chip to make these predictions cost-effectively."

Related Links:
Emory University School of Medicine
Yerkes National Primate Research Center
National Institute of Allergy and Infectious Diseases