While the microbiome has gained significant attention for its impact on digestive health in recent years, its effect on lung disease has largely remained unstudied.
“The microbiome is the ecosystem of good and bad bacteria living in the body,” said Dr. Patricia Finn from University of Illinois at Chicago. Because the lungs continuously and automatically draw air, and any number of environmental agents, into the body. The composition and balance of microbes in the lungs may have a profound effect on many respiratory conditions.
However, Finn and her colleagues suggest that the lung microbiome plays a significant role in asthma severity and response to treatment.
Asthma is a chronic disease in which lung airways become swollen and narrow, making it difficult for air to move in and out of the lungs. People with asthma have inflamed airways, they experience a shortness of breath, coughing, wheezing and chest tightness.
In a group of asthma patients, researchers identified two asthma phenotypes by assessing the microbiome and airway inflammation. The patients age between 18 to 30 with mild or moderate atopic asthma.
“This tells us the microbiome has relevance beyond the gut, and that it is a potential biomarker for asthma,” said Dr. David Perkins, professor of medicine and surgery at UIC, who jointly operates the lab with Finn.
The two asthma phenotypes AP1 and AP2 separated by the prevalence and dominance of different bacteria in the lung. When compared, patients in the two groups performed differently on pulmonary function tests.
In tests, AP1 associated with less severe asthma. It decreases T helper cytokines and increased enterococcus bacteria, but normal pulmonary function tests. However, AP2 associate with increased pro-inflammatory cytokines, oral taxa and strep pneumonia bacteria, and decreased pulmonary function tests, or more severe asthma.
In both AP1 and AP2, the associations between the composition of the microbiome and specific inflammatory cytokines decreased after treatment with an inhaled corticosteroid, a common asthma therapy.
The data suggest that further study of the microbiome may help to develop more personalized treatment recommendations for patients with asthma.
More information: [PLOS ONE]