Getting to the root of peanut allergies:
Dr. Jean Marshall co-leads national food allergy research effort
Food allergies have become epidemic in the Western world, with peanuts triggering the most severe and potentially deadly reactions. Dalhousie Medical School immunologist Dr. Jean Marshall is co-leading a new national research team, the Canadian Group on Food Allergy Research, to tackle the problem. The group wants to get to the root of peanut allergies and find ways to better diagnose, treat and even prevent them.
“We want to know why some people become allergic to peanuts, while others become tolerant,” says Dr. Marshall, head of Dalhousie’s Department of Microbiology & Immunology. “Peanut allergy is so prevalent and people can be exposed in unexpected ways, such as through peanut oils in processed foods and skin care products. But our findings will shed light allergies to many types of foods.”
Dr. Marshall wants to outsmart the immune system. “We may be able to introduce peanut proteins in a way that induces tolerance, much like a vaccine induces immunity,” she explains. The group’s work may also lead to ways of diagnosing peanut allergies and predicting who will outgrow their peanut allergy. Dr. Marshall is working with Dr. Wade Watson, head of the Division of Allergy in the Department of Pediatrics at Dalhousie and the IWK Health Centre, to see if a blood test can accurately show who will have a severe reaction and who will not.
The group’s findings may also lead to scientifically sound dietary advice for pregnant women, nursing mothers and parents. “It’s no longer certain that delaying exposure is the right thing,” notes Dr. Marshall. “In Thailand, they use boiled peanuts as an early food, and they have very low levels of peanut allergies. Maybe the way peanuts are prepared makes a difference.”
Dr. Marshall’s interest in allergies grew out of her 20 years of research into mast cells – sentinel cells of the immune system that call up other immune cells to fight bacteria, viruses and other foreign invaders. Mast cells also play a crucial role in keeping cancer cells at bay. In other studies Dr. Marshall is looking for ways to stimulate mast cells to fight tumours more aggressively.