Alveolar macrophages, immune cells found in the lungs' air sacs, typically serve to protect lung health and prevent unnecessary immune responses. Research led by Prof. Bart Lambrecht and Prof. Martin Guilliams at the VIB-UGent Center for Inflammation Research has revealed that these cells can change roles during allergic reactions.
The study used a mouse model to observe how exposure to allergens causes alveolar macrophages to adopt an inflammatory state. In this mode, they release signals that attract additional immune cells into the lung, increasing inflammation and worsening allergic symptoms. The researchers also observed that these macrophages can fuse together into larger 'giant cells,' altering lung tissue structure during allergy episodes.
Prof. Lambrecht and Prof. Guilliams' findings challenge previous assumptions that alveolar macrophages are stable and resistant to environmental changes. Instead, their research shows that these cells are adaptable and can be reprogrammed by their surroundings, sometimes leading to negative effects.
"This influx amplifies inflammation and worsens allergic reactions," the research team stated in their findings.
The implications of this discovery extend to diseases like asthma, where current treatments focus on other immune cells or inflammatory molecules. By identifying alveolar macrophages as key contributors to allergic inflammation, the study suggests new directions for developing therapies aimed at controlling or reversing this harmful transformation while maintaining necessary lung functions.
The results provide insight into how allergic reactions develop in the lungs and underscore the complex role of immune cells in both protecting against and contributing to disease.
