A research team led by Dr. Tillie Hackett of the Centre for Heart Lung Innovation at St. Paul’s Hospital has identified the precise cells that destroy the lungs’ smallest airways in chronic obstructive pulmonary disease (COPD).
Their findings, published today in the American Journal of Respiratory and Critical Care Medicine, build on their 2018 study in The Lancet Respiratory Medicine that found by the time people are diagnosed with mild COPD, more than 40 per cent of their small airways are already destroyed.
Research marks closest way yet to finding a prevention
With today’s research together with the Lancet Respiratory Medicine study, “This is the closest we have come to finding a way to potentially prevent COPD,” says Dr Hackett.
COPD is the third leading cause of death worldwide. About 380 million people globally live with it, and each day is a struggle simply to breathe. The disease is commonly associated with smoking, exposure to air pollution, and genetics. To date, there is no cure for COPD and current treatments only manage symptoms, but cannot improve lung function.
Understanding the cells involved in small airway loss can lead to more effective treatments for COPD patients, says Dr. Hackett.
Using lung tissue samples donated by 40 COPD patients, the team performed high-resolution imaging studies to investigate small-airway disease at the single-cell level.
The authors found that in patients with COPD, there is a progressive loss of structures called alveolar attachments that normally hold the small airways open. “Airways are like flexible pipes that bring air in and out of the lung, and the alveolar attachments are like cables that attach to the airway wall and hold it open,” says Dr Hackett. Without these attachments, the airways collapse and airflow is obstructed. This makes breathing difficult.
Creating an “atlas” of COPD small airways
“By using these imaging techniques, we have been able to identify the specific cell types involved in the inflammatory response that destroys the small airways,” says Dr. Steven Booth, first author of today’s publication and PhD student of Dr. Hackett.
For today’s study, the authors created a single-cell “atlas” of COPD small airways using imaging mass spectrometry. This technology is the first of its kind on the West Coast of Canada and is funded in part through the St. Paul’s Foundation and the Canada Foundation for Innovation. With the equipment, every cell within the diseased lung can be studied. Previously, researchers could only look at one cell at a time. Dr. Booth says this technology now enables us to create a map of small airways to understand which cells are causing the damage.
COPD BY THE NUMBERS
- COPD is the third leading cause of death worldwide, responsible for 3.23 million deaths globally in 2019.
- Tobacco smoking and air pollution are the most common causes of COPD.
- COPD costs the healthcare system $1.5 billion annually in Canada.