Writing in the Journal of Immunology, the researchers reported that it is possible to ‘turn off’ the potentially life-threatening allergic response to peanuts by tricking the immune system into thinking the nut proteins aren’t a threat to the body.
The peanut tolerance was achieved by attaching peanut proteins onto blood cells and reintroducing them to the body - an approach which the researchers suggest may ultimately able to target more than one food allergy at a time.
“We think we’ve found a way to safely and rapidly turn off the allergic response to food allergies,” said Paul Bryce, an assistant professor of medicine in the division of allergy-immunology at Northwestern University Feinberg School of Medicine, USA.
Using a mouse model that mimics a severe human peanut allergy, Bryce and his team attached peanut proteins to white blood cells (leukocytes) of mice and infused them back into the blood stream. After two treatments, the mice were then fed a peanut extract.
The authors reported that the peanut extract did not cause any allergic reaction, explaining that the immune system now recognized the protein as safe.
“Their immune system saw the peanut protein as perfectly normal because it was already presented on the white blood cells,” Bryce said.
“Without the treatment, these animals would have gone into anaphylactic shock.”
Bryce said that more than one protein can be attached to the surface of the cell and, thus, there is potential to target multiple food allergies at one time.
Bryce noted that whilst there are many differences between immune responses in mice and humans, “there are also many similarities.”
He explained that the same principles used in the current research are being applied to autoimmune diseases such as rheumatoid arthritis and multiple sclerosis – which work very much in the same way as allergies do.
“The only difference is that the protein being attacked is part of the person’s own body, rather than a food that is consumed,” explained Bryce, noting that research using the method in autoimmune diseases is further along.
“This approach to inducing tolerance is in early clinical trials for multiple sclerosis,” Bryce said. “We are hopeful that any success there would justify further trials, including those designed to test its use for food allergy.”
Source: Journal of Immunology
Published online ahead of print, doi: 10.4049/jimmunol.1100608
“Antigen-Fixed Leukocytes Tolerize Th2 Responses in Mouse Models of Allergy”
Authors: C.B. Smarr, C.L. Hsu, A.J. Byrne, S.D. Miller, P.J. Bryce