BETHESDA, Md., April 1 (UPI) -- A U.S.-led international team of scientists found certain lung cells can be used in the human immune response for sensing airborne allergens.
Researchers at the National Institute of Allergy and Infectious Diseases in Bethesda, Md., and Ghent University in Belgium said foreign substances, called antigens, are inhaled daily, however the lungs have mechanisms that usually prevent people from unwanted allergic immune responses to the materials. But sometimes immune responses are generated, resulting in allergic responses and asthma. Scientists have been working to understand what triggers such undesirable airway responses.
The new research, conducted with mice, involved sensors called Toll-like receptors that are found on the surface of epithelial cells lining the lungs. The TLRs can detect the presence of antigens and produce signals that activate immune cells.
Previously it was unclear whether TLRs on non-immune epithelial cells at mucosal surfaces, such as those in the lungs, were involved in antigen sensing, or if it was TLRs found on immune cells that were critical to the allergic responses. The research team discovered a particular TLR, called TLR4, on airway epithelial cells, not on immune cells, helped induce the initial immune response to antigens in the lungs.
The scientists said their finding suggests targeting TLRs might be a research avenue for developing new treatments for allergic diseases such as asthma.
The study appears in the journal Nature Medicine.
