Winning the asthma race.

Protein may lead to small airway disease detection.

An article by Clare Illingworth, SPARK writer, University of Guelph.


Hay, cause mould and dust in a stable can cause a sensitive horse to cough and wheeze. Those barn allergens can small airway disease (SAD), producing symptoms similar to those of asthma in humans. Now, University of Guelph researchers think a specific protein may give them answers needed to prevent the disease from causing long-term damage.

Prof. Dorothee Bienzle and graduate student Paula Katavolos of the Department of Pathobiology are studying that protein — CC10 — to see if it can give some insight into the mechanisms of SAD and provide a means of early detection.

Identifying the irritant.
The researchers believe that in horses affected by SAD, their Clara cells — the cells that line much of the smallest airways — become inflamed, causing the airways to constrict. Clara cells are among some of the horse’s first line of defence against SAD.

“We may be able to treat and detect the disease better by understanding the role of these cells and the protein they release,” says Katavolos.

Repeated irritation of the horse’s smallest airways will damage or “exhaust” important Clara cells faster than they are replaced. In their absence, the anti-inflammatory protein CC10 is not expressed. Bienzle and Katavolos believe that without CC10, inflammatory lung damage causes persistent inflammation and permanent callusing.

Callused windpipes don’t expand to meet the increased air intake of athletic horses, putting an end to many performance careers and, in severe cases, compromising their qual-ity of life.

In their research, the team is compar-ing a healthy group of 10 horses with 10 horses suffering from SAD. Overall health, lung function and Clara cell structure will be assessed and related to CC10 protein in lungs and blood. Katavolos hopes to quantify the amount of CC10 protein and relate it to the cellular changes observed in lung tissue from both groups.

Determining the change
“Right now, it’s unknown why some horses are more affected by barn allergens than others or how CC10 reduces the degree of inflammation in horses with SAD,” she says. “Learning what affects the presence of CC10 will help us detect and understand the mechanisms of SAD.”

This research is sponsored by the Ontario Ministry of Agriculture and Food.