Miyata J, et al. - Researchers characterized functional characteristics of eosinophils present in allergic inflammatory tissues by analyzing eosinophils from nasal polyps of patients with eosinophilic rhinosinusitis (NP-EOS) vs peripheral blood-derived eosinophils from healthy subjects (PB-EOS) in multi-omics analysis including lipidomics, proteomics, and transcriptomics. In lipidomic analysis, impaired synthesis of prostaglandins and 15-lipoxygenase (15-LOX)-derived mediators, and selective upregulation of leukotriene D4 production was seen. They also observed changes in the expression of specific enzymes (GGT5, DPEP2, and 15-LOX) responsible for dysregulated lipid metabolism in proteomics and transcriptomics. Overall, a specific phenotype of inflammatory tissue-derived eosinophils was identified that involved dysregulated fatty acid metabolism. This could be a therapeutic target to control eosinophilic inflammatory diseases.