Asthma is a common long-term inflammatory disease of the airways of the lungs. With the condition, the lungs react to an allergen or pollutant. Such an invasive particle can trigger airflow obstruction, and bronchospasm, leading to wheezing, coughing, chest tightness, and shortness of breath.
The new method aims to block the allergic reaction and to stop the airway from responding. It works by seeking to create tolerance in the immune system. The study has, so far, been carried out in mice. A clinical trial involving people is currently being set-up.
The idea is to add to nanoparticles the very thing that a person is allergic to and to introduce these in low quantities so that tolerance is built up. The nanoparticles are made from a biopolymer called PLGA (formed from lactic acid and glycolic acid, which have met U.S. Food and Drug Administration safety checks.)
In the study, allergen-packed nanoparticles were injected into the bloodstream of mice (the test allergen was egg protein.) The immune system, once the optimal level was selected, did not react because the level of allergen was too low. When white blood cells eventually engulf the nanoparticle the allergen is presented to the immune system as a ‘non-treat.’ The immune system learns this, and as the allergen is introduced at higher levels an allergic response does not occur,
The research team hope the new method can be applied to food allergies as well, with the long-term aim of creating a universal allergy treatment. Trials are underway looking at peanut allergies using a mouse model.
The research has been conducted by Northwestern University Feinberg School of Medicine. The findings are published in the journal Proceedings of the National Academy of Sciences. The research is titled “Biodegradable antigen-associated PLG nanoparticles tolerize Th2-mediated allergic airway inflammation pre- and postsensitization.”