Macrophages are crucial to innate immunity, eliminating pathogens and damaged tissues through phagocytosis and modulating immune responses. Recently, macrophage extracellular traps (METs) have been identified as chromatin-based structures composed of DNA and various immune-related proteins. While METs play a defensive role in trapping and neutralizing pathogens, they are also implicated in disease pathology, contributing to chronic inflammation, tissue damage, and immune dysregulation. The precise mechanisms regulating MET formation are still under investigation, but emerging evidence indicates the involvement of various regulatory factors. Dysregulated MET activity has been associated with various diseases, including autoimmune disorders, cancer, and neurological conditions. A deeper understanding of MET mechanisms and their pathological impact may offer novel therapeutic strategies. Given the limited number of reviews and articles on METs, this review provides valuable insights into MET formation, regulatory pathways, and their role in disease progression.
Keywords: Autoimmune diseases; Cancer; Inflammation; MET formation; Macrophage extracellular traps (METs); Neutrophil extracellular traps (NETs); Peptidyl arginine deiminase 4 (PAD4).
© 2025. The Pharmaceutical Society of Korea.