St. Jude Children's Research Hospital will lead a groundbreaking international effort aimed at finding how initial exposure to the flu can leave lifelong impacts on a child's developing immune system.
The National Institute of Allergy and Infectious Diseases awarded St. Jude a $35 million grant to direct the study, which involves investigators at 12 research and medical institutions in the U.S., New Zealand, Australia and Nicaragua. The researchers will follow about 3,000 children for seven years, beginning before birth, to examine how their first exposure to influenza – whether through vaccination or infection – shapes their response to it for the rest of their lives.
Scientists have found evidence the first encounter with the flu leaves "imprints" on the developing immune system that shape the body's response to different influenza viruses for decades to come, said the study's principal investigator, Paul Thomas, a member of the St. Jude Department of Immunology. The other principal investigator is Aubree Gordon of the University of Michigan.
“This study provides an opportunity to understand how imprinting affects individuals’ immune memory and their ability to confront flu on subsequent exposures,” Thomas said. “Understanding the mechanism could lead to vaccines that ‘train’ the immune response to be more effective against a wider variety of flu viruses.”
Although it is better known for treating pediatric cancer, St. Jude is a global leader in influenza research, and is a World Health Organization Collaborating Center for Influenza.
Researchers hope the study will lead to more effective strategies to ward off the flu, possibly resulting in a universal vaccine to replace yearly vaccinations. Flu and one of its common complications, pneumonia, remain significant causes of death in the U.S.
Through past studies of pandemic flu outbreaks, researchers found an association between flu susceptibility and severity and flu exposure early in life. By tracking the kids for seven years, investigators hope to find how early flu exposure affects the B cells, antibodies and T cells produced in response to flu exposure in the future.
Researchers at Children’s Hospital Los Angeles, as well as in New Zealand and Nicaragua, will recruit the children to be enrolled in the study. The subjects' response to flu will be tracked through blood samples, which will be stored at St. Jude. Scientists at St. Jude and the other participating centers will conduct the analyses.
The grant for the international study was announced on the same day that St. Jude researchers reported that, far from being just potent health hazards on their own, the influenza virus and common respiratory bacteria appear to work in tandem to increase the threat of infections such as bacterial pneumonia.
In research published online this week by the journal Nature Microbiology, St. Jude scientists reported on evidence the flu virus clings to the surface of respiratory bacteria, enhancing the likelihood the bacteria will stick to cells lining the airways. Once lodged there, the bacteria have gained a foothold from which they can transmit infection.