Airway mucus consists of various proteins such as long mucins MUC5AC and MUC5B, both of which contribute greatly to the proper gel-like consistency of this most essential bodily fluid.
UNC School of Medicine researchers led by mucin expert Mehmet Kesimer, PhD, had previously discovered that the total mucin concentrations in the lungs are associated with COPD disease progression and could be used as diagnostic markers of chronic bronchitis, a hallmark condition for patients with COPD. Kesimer and colleagues now report that one of these mucins, MUC5AC, is more closely and reliably associated with the development of COPD than is its brother, MUC5B.
The research, published in The Lancet Respiratory Medicine, shows that MUC5AC is found at elevated levels in smokers who had not yet developed COPD but whose lung function wound up decreasing over the course of the three-year study. Former smokers at-risk for COPD, on the other hand, had normal levels of MUC5AC at the start of the study and maintained proper lung function over three years. MUC5AC hyper concentration in the lungs may be a key factor in predicting the risks and rates of progression to more severe disease, according to the study.
Recent nationwide efforts have focused on early- or pre-COPD to predict the risks of progression to COPD amongst smokers.
“Currently, we cannot forecast which individuals in the at-risk smokers group will progress to COPD because we don’t have an objective biological marker to underpin the disease-causing pathways. Our research shows that MUC5AC could be a predictor of who will develop COPD from the large group of aging “at-risk” smokers,” said Kesimer, Professor in the UNC Department of Pathology and Laboratory Medicine, and member of the UNC Marsico Lung Institute. “We think MUC5AC could be a new biomarker for COPD prognosis and it could be a biomarker for testing the effectiveness of therapeutic strategies.”
MUC5AC could also become a target for pharmaceutical developers whose goal it is to halt COPD disease progression and help patients live more normal, active lives.
Smoking cigarettes has long been known to be a major risk factor for COPD, but Kesimer’s work suggests that quiting smoking decreases the odds of developing COPD as we age.