Consumers with allergies to pollen can often be found using nasal sprays that help limit their symptoms. Now, researchers have used a nasal spray to suppress peanut allergy symptoms in mice.
“Right now, the only FDA-approved way to address food allergy is to avoid the food or suppress allergic reactions after they have already started,” said lead author Jessica O’Konek, Ph.D., in a news release. “Our goal is to use immunotherapy to change the immune system’s response by developing a therapeutic vaccine for food allergies.”
O’Konek and other researchers used an ultrafine nasal spray to limit or prevent peanut allergy symptoms in mice that had been sensitized to peanut, according to a study published today in the Journal of Allergy and Clinical Immunology and supported by Food Allergy Research & Education, the leading organization working on behalf of patients with food allergies and the largest source of private funding for food allergy research.
During an allergic reaction, the body’s immune system overreacts to an allergen. Allergen immunotherapy attempts to retrain the immune system to tolerate the allergen. Other peanut allergy immunotherapies being tested in human clinical trials have been shown to improve peanut tolerance in many, but not all, peanut allergy patients. This tolerance can be lost if maintenance doses of peanut are discontinued; additionally, adverse reactions can occur during immunotherapy.
“We are committed to the development of new food allergy immunotherapies and pleased to report these promising results,” said Mary Jane Marchisotto, FARE’s senior vice president for research and international operations. “This serious and potentially life-threatening disease affects 15 million Americans and is becoming increasingly prevalent. Emergency care for severe allergic reactions has increased almost 400 percent during the past decade. Effective treatments are urgently needed.”
The vaccine research team is working to develop a safe, durable and more widely effective new form of immunotherapy. The experimental immunotherapy vaccine consists of peanut protein and nano-emulsion, tiny droplets of highly purified soybean oil, detergents and water mixed at high speed. The average diameter of the droplets is 350-400 nanometers, roughly 200 times smaller than the average diameter a human hair.
“We’re changing the way the immune cells respond upon exposure to allergens,” O’Konek explained. “By re-directing the immune responses, our vaccine not only suppresses the response but prevents the activation of cells that would initiate allergic reactions. Importantly, we can do this after allergy is established, which provides for potential therapy of allergies in humans.”
Additional studies in mice are ongoing to determine if the vaccine’s protection will endure over a longer period. Future studies in mice may reveal more details about the mechanisms responsible for that protection. If successful, these experiments could eventually lead to a clinical trial of the vaccine in humans.