Allergic asthma is the most common form of asthma. It affects people of all ages. As the name implies, it is triggered by allergens—substances that cause an allergic reaction. Common allergens include pollen, mold, dust mites, pets and cockroaches.
During an allergic asthma attack, patients suffer from wheezing, chest tightness, shortness of breath and coughing.
“All of these symptoms are manifestations of hyperresponsive respiratory cells that cause narrowing of the airway passages along with excess mucus/phlegm production,” said Hitendra Chand, a researcher in the Department of Immunology and Nano-Medicine at the Herbert Wertheim College of Medicine.
Phlegm is a thick and sticky secretion that plays a vital role in protecting the lungs from environmental factors by acting as a filter. It traps and removes inhaled allergens from the respiratory passages and lungs. But uncontrolled phlegm production can block the airways and severely affect lung function.
Dinesh Devadoss, a post-doctoral associate in Chand’s lab, studies the role of respiratory epithelial cells—which line the respiratory tract— in allergic asthma. In a recent study published in the Nature journal, Mucosal Immunology, Devadoss reports that “respiratory epithelial cells undergo a functional reprogramming to modulate mucus response, and these mechanisms are dysregulated (impaired) in asthmatics.”
Using next-generation sequencing and cutting-edge molecular imaging technologies, Devadoss and colleagues identified the genetic factors called long noncoding RNAs that help shape the immunologic memory of respiratory cells—also known as trained immunity. Immunological memory, or training, allows these cells to respond more rapidly and effectively to germs they have encountered before. The findings suggest these training mechanisms of respiratory cells could be targeted to help control allergic asthma.
There is no cure for asthma, and severe cases can be fatal. According to the Centers for Disease Control and Prevention, more than 3,000 Americans die from asthma every year. African-Americans are three times more likely to die from asthma than any other group.
Current treatments are effective in managing mild-to-moderate allergic asthma but are less successful in controlling severe asthma.
“This seminal research provides a key foundation toward developing new ways of diagnosing and treating diseases like allergic asthma,” Chand said.