The role of Apical Junction Complex in airway epithelial repair and differentiation in asthma

Asthma is a serious global health problem, affecting over 300 million people worldwide. The disease is predominantly an inflammatory disorder of the conducting airways, and can be treated or controlled using current therapies. However, un-controlled asthma leads to continual inflammation and damage, resulting in permanent scaring which is termed airway remodeling. Airway remodeling can be defined as changes in the composition, content and organization of cellular and molecular constituents of the conducting airways. One of the structural changes that occurs as a result of airway remodeling is detachment of the cells that line the surface of the airways, called the epithelium. In normal airways, the epithelium forms a barrier against the inhaled external environment which includes aero allergens, viruses and particulate matter, through the formation of apical junction complexes (AJCs). In asthma, part of the abnormal response to inhaled allergens is thought to be due to impaired barrier function caused by damage to the airway epithelium and loss of AJCs. Emerging evidence suggests that AJCs are able to influence other aspects of epithelial function such as release of inflammatory mediators and mechanisms of epithelial repair. Building on earlier work in this area, Dr. Tillie-Louise Hackett’s current research is designed to determine whether AJCs play an important role in normal airway epithelial repair and if the mechanisms involved are altered in asthmatic patients. The results of her research will provide scientists and clinicians with a better understanding of the pathological mechanisms that contribute to multiple respiratory diseases. In addition, Dr. Hackett’s findings will open avenues for the development of new therapeutics to improve the lung health of Canadians living with obstructive lung diseases, such as asthma and Chronic Obstructive Pulmonary Disorder.