Grant: Doctoral Award - Frederick Banting and Charles Best Canada Graduate Scholarships

Allergy is one of the most common problems in the industrialized world. Allergic disease may develop in children and infants, as exposure to allergens during infancy may result in adult allergic disease. Infant immunity is biased towards a protective immune response in order to prevent strong inflammation, which may damage tissues and cause infant mortality. Without exposure to microbes during childhood, this protective immunity may become overactive, responding to allergens (harmless environmental stimuli) and resulting in allergic disease in adults. This is known as the Hygiene Hypothesis. Our previous research has identified a new type of immune cell called ILC2 in adult mice that is essential for lung allergic inflammation. We have also found that after an initial allergen stimulus lung ILC2s can respond more intensely with subsequent allergen exposure. Furthermore, microbial exposure inhibits ILC2 function in adult mice. However, it remains unclear if ILC2s are present within the neonatal lung and if at this crucial time in development, they are influenced by allergen or microbial exposure altering the chance of acquiring adult allergic disease. This project addresses two fundamental questions in allergy research: the Hygiene Hypothesis, and the effects of infant exposure to allergens on allergy development in adults. The obtained results will emphasis the importance of proper early immune education, which is especially important in industrialized countries where the prevalence of allergic disease has continued to rise for more than 50 years.