In a recent study by ILH/DZL researchers at the Cardio-Pulmonary Institute (CPI) at Justus Liebig University Giessen (ILH/DZL site UGMLC), a previously unknown mechanism regulating the immune response in the lungs was discovered. The findings were published in the prestigious journal Science Immunology.
The researchers investigated how alveolar macrophages, key immune cells in the lungs, adapt their function in the fight against inflammation and infection. Their discovery shows that these macrophages alter their metabolism by engulfing dead neutrophil granulocytes (a type of white blood cell), taking on an anti-inflammatory role. This process helps efficiently resolve lung inflammation but simultaneously impairs the macrophages' ability to fight bacterial infections.
"Our study shows that the phagocytosis of neutrophils alters the macrophages' activity and shifts them into an inflammation-resolving state," says Dr. Ulrich Matt, lead author of the study. "This discovery provides crucial insights into the balance between inflammation resolution and infection control, a central issue in pneumonia of any kind."
The researchers now aim to use these insights to develop therapies for severe lung infections.
Original publication: Julian Better et al.: Cell type-specific efferocytosis determines functional plasticity of alveolar macrophages. Sci. Immunol. 10, eadl3852 (2025). DOI: 10.1126/sciimmunol.adl3852.
