DNA Verification Of Peanut Allergy Treatments

February 1, 2014

Brett Smith for redOrbit.com Your Universe Online

Scientists with Stanford University are finding that healing a peanut allergy with oral immunotherapy alters the DNA of the patients immune cells. The finding could serve as the basis for a simple blood test to monitor the long-term effectiveness of the allergy therapy.

Allergy scientists are currently performing clinical trials of doctor-supervised immunotherapy involving peanut-allergy sufferers taking escalating amounts of peanut powder in an attempt to desensitize them to the nuts. At the conclusion of the trial, patients are usually expected to eat some peanuts every day throughout their lives.

At first, eating two peanut butter cups a day might seem fun, but it gets a little boring and a lot of people might stop, said Dr. Kari Nadeau, an immunologist at Stanford Hospital & Clinics and Lucile Packard Childrens Hospital Stanford.

Until now, doctors couldnt test if patients who had finished immunotherapy could safely give up eating daily doses of peanuts, she said.

Our new finding can help us try to determine whether, for the long term, someones allergy has truly been shut off so people can eat ad lib, Nadeau said.

In the study, which was published in the Journal of Allergy and Clinical Immunology, the scientists evaluated 20 peanut-allergic adults and children who had concluded two years of immunotherapy, which made it possible for them to eat one 4-gram serving of peanuts daily without experiencing a major allergic reaction.

The patients were asked to stop consuming peanuts for three months and were then given a bit of peanut powder to see if their allergy returned. Thirteen of the patients had a relapse of their allergy, while seven did not. The scientists evaluated the immune cells in the blood of patients from the two groups. Blood samples from peanut-allergic participants who had never acquired the immunotherapy were utilized as a control.

The scientists focused on the regulating T cells, which are white blood cells that help to reduce an allergic reaction. In these cells, the DNA at a gene called forkhead box protein 3 (FOXP3) was somewhat different in each of the three sets of patients. The FOXP3 gene has been previously found to play a role in allergies.

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DNA Verification Of Peanut Allergy Treatments