Polyunsaturated fatty acid-derived lipid mediator networks characterize COVID-19 severity and risk for critical illness

Severe COVID-19 is characterized by excessive inflammation leading to the development of pneumonia and acute respiratory distress syndrome. Bioactive lipid mediators (LMs) derived from ω6 and ω3 polyunsaturated fatty acids are central to the regulation of inflammation, controlling both its initiation and resolution. Still, their role in COVID-19 remains underexplored. By employing a holistic approach involving the analysis of white blood cell transcriptomes, targeted lipidomics, cytokine and immune cell profiling, across the spectrum of disease severity groups, we now show that LM networks are profoundly altered in COVID-19, correlate with inflammatory patterns, and stratify patients according to disease severity. Central to this are CYP450-derived LMs such as 20-HETE, lipid peroxidation metabolites such as iPF2a-VI, and lipoxygenase-derived LMs such as 12-HETE, all of which are major vasoactive mediators of inflammation. Among them, 20-HETE appears to be a promising prognostic biomarker for ICU admission and a potential therapeutic target for severe COVID-19 disease. Our study thus underscores the significance of LM networks in COVID-19 pathophysiology and sheds light into the broader mechanisms driving viral pneumonia in humans.