Neutrophil Extracellular Traps: Formation and Involvement in Disease Progression

Neutrophils are the forerunner in innate immunity by defending the host organisms against infectious pathogens. During such process, neutrophils reach the site of inflammation/infection and eliminate the pathogens by phagocytosis as well as by forming the neutrophil extracellular traps (NETs). NETs trap and eradicate a number of microbes including bacteria, fungi, protozoa, viruses. NETs consist of DNA which is decorated with histones and granular proteins such as neutrophil elastase (NE), gelatinase, myeloperoxidase. NETosis (a process of NETs formation) is also involved in many inflammatory and autoimmune disorders with a major contribution to acute respiratory distress syndrome, sepsis, cystic fibrosis, periodontitis. Hyper NETosis or ineffective clearance of NETs would likely increase the risk of autoantibody generation against NETs components and contribution in autoinflammatory diseases. The purpose of this review is intended to highlight the molecular mechanisms of NETosis and its antimicrobial effect. Furthermore, a current status of NETosis in the pathogenesis of inflammatory and autoimmune disorders has been reviewed for better understanding.