A team of researchers led by Dr. Julia Esser-von-Bieren, Institute of Allergy Research, was able to show for the first time that immune cells of patients with severe chronic inflammation of the respiratory tract have an inflammatory memory. Their results, published in the Journal of Allergy and Clinical Immunology, could explain why infections often lead to an acute worsening of asthma.
The group with first author Pascal Haimerl examined macrophages differentiated from blood monocytes of patients with respiratory symptoms such as asthma and nasal polyps, which are summarized under the name "N-ERD”. The cells of N-ERD patients showed an altered fatty acid metabolism and increased reactions to immunological stimulation, e.g. by bacterial toxins, which is referred to as "trained immunity". So far, trained immunity was only known in connection with arteriosclerosis and acute infections. The inflammatory memory of macrophages could explain why infections often lead to an acute worsening of asthma.
Publication: P. Haimerl et al.: Inflammatory macrophage memory in NSAID-exacerbated respiratory disease. The Journal of Allergy and Clinical Immunology. DOI: https://doi.org/10.1016/j.jaci.2020.04.064