Dr. Richard Leigh

When Heritage Clinical Investigator Dr. Richard Leigh’s patients describe their asthma symptoms, he really knows what they’re talking about. An asthmatic himself, Dr. Leigh is a specialist in respiratory medicine who treats patients with asthma and chronic obstructive pulmonary disease (COPD), and who also does research on these conditions.

His particular interest is the nature of the chronic airway inflammation that is a hallmark of asthma. This inflammation causes structural changes in the airway walls—a process called “airway remodelling” which is thought to play an important role in the persistence of airway hyper-responsiveness. This is the exaggerated response by which the airways constrict too much and too quickly in response to inhalation of airborne allergens, such as cat dander or house dust, or non-specific irritants such as tobacco smoke.

Dr. Leigh explains: “For example, right now I’m unlikely to have overt airway inflammation. But if I were to go running outdoors on a very cold day, I would start to experience chest tightness and wheezing. The question is: Why am I getting chest tightness and wheezing if I don’t have inflammation? It’s probably because of the underlying structural changes in my airways.

“We’ve been treating inflammation in asthma for 25 years. We have appropriate medications—inhaled corticosteroids—that are very effective in treating airway inflammation. Yet people continue to experience ongoing asthma symptoms; and, sadly, some still die from the condition. The next big breakthrough in asthma treatment will likely come from a paradigm shift where we start to treat airway remodelling. My research is aimed at understanding how we might do that.”

Dr. Leigh studies the possible mechanisms behind airway inflammation and remodelling. These include the response of cells to mechanical strain and the effects of viral infections in the development of airway remodelling. Work done in the United States shows that about 50% of young children who have viral bronchiolitis (sometimes called wheezy bronchitis) go on to develop asthma later. “We know that airway remodelling happens very early on in asthmatics, by the time they are five or six years old,” notes Dr. Leigh, “but it’s not understood how childhood virus infections contribute to airway remodelling.”

Part of his research involves a new sputum test that shows whether a patient’s lungs are producing the inflammatory cells that cause asthma. It was developed at McMaster University, where Dr. Leigh did his Ph.D. This simple, non-invasive test makes it much easier to diagnose and assess asthma in the clinic. It is also a valuable research tool for measuring airway inflammation and an excellent alternative to current tests that are both time-consuming and invasive.

Much of Dr. Leigh’s research is done in collaboration with other members of the University of Calgary’s Airway Inflammation Research Group, including Dr. David Proud and Heritage researchers Dr. Rob Newton and Dr. Mark Giembycz. “Collaborating with outstanding basic scientists provides a strong synergy for the type of translational research I do. It allows us to understand the molecular and cellular mechanisms of airway remodelling and apply it to patients. That’s the beauty of translational research.”

Dr. Richard Leigh, an AHFMR Clinical Investigator and a CIHR Clinician Scientist, is an assistant professor in the Department of Medicine and the Department of Physiology and Biophysics at the University of Calgary. He also receives funding from the Alberta Lung Association.

Photo: Trudie Lee

For further information, please contact Dr. Richard Leigh using the Email contact form or by phone at 403 210-8851