Ferritin-induced NETs lead to cytokine storm in AOSD

The spectrum of hyperferritinaemic syndrome encompasses clinical conditions including adult-onset Still disease (AOSD), macrophage activation syndrome, catastrophic anti-phospholipid syndrome and septic shock, and severe COVID-19. Emerging evidence suggests that ferritin, rather than being a biomarker of the inflammatory response, might contribute directly to the pathogenic mechanism that results in systemic inflammation. A study shows that ferritin promotes neutrophil activation and the formation of neutrophil extracellular traps (NETs) via the ferritin receptor macrophage scavenger receptor 1 (MSR1) and highlights the therapeutic potential of targeting this pathway. "Hyperferritinaemia and neutrophil activation are hallmarks of AOSD". "This study reveals the pro-inflammatory role of ferritin, thereby improving the understanding of the common mechanisms behind the spectrum of hyperferritinaemic syndrome."