Grant: Catalyst Grant: Sex as a Variable in Biomedical Research

Asthma is one of the most common health problems in Canada. Many studies have found that adult women are more likely to develop asthma than adult men, but the precise reason for the gender difference in asthma incidence is currently unknown. Asthma is caused by over-production of a group of proteins called type 2 cytokines that induce excessive mucus production and narrowing of airway, which result in breathing difficulty. We have found a family of innate lymphocytes called ILC2 that produces large amounts of type 2 cytokines. We have also found that asthma risk gene called Rora regulates ILC2. Studies on the Rora gene by other groups have found that sex hormones may regulate the gene. Therefore, we think female sex hormones act on the Rora gene and increase the number of ILC2, resulting in more type 2 cytokine production and asthma development. We will test this idea by comparing the numbers of ILC2 and the expression the Rora gene in male and female mice. We will also test the effects of sex hormones on ILC2 in cultures as well as asthma development in mice. Through this study, we hope to find out why adult women are more likely to get asthma than men. This study may result in new ways to treat asthma patients.