Although the immune system is designed to protect the body from harm, it may actually worsen one of the most difficult-to-treat respiratory diseases: chronic obstructive pulmonary disorder (COPD), according to new University of Cincinnati (UC) research.

In a preclinical research study, UC environmental health scientists have identified a link between cigarette smoke and activation of a specific cellular receptor (NKG2D) critical to immune system activation. They say the finding is key to understanding COPD disease progression and developing future interventional drug therapies.

"People have historically believed that if you smoke, you suppress the immune system. We've shown that you actually activate certain parts of the immune system and it could potentially work against you," explains Michael Borchers, PhD, lead investigator of the study and UC assistant professor of environmental health.

Borchers and his team report their findings in the March 2009 issue of the Journal of Clinical Investigation. The study appears online ahead of print Feb. 9, 2009. It is the first study to report data defining a link between the immune system and COPD disease progression and severity.

COPD is a progressive pulmonary disease believed to be caused by long-term cigarette smoking…