Background and aim:
Neutrophil extracellular traps (NETs) are structures containing chromatin that are coated with histones and cytoplasmic proteins. In ۲۰۰۴, NETs were thought to be a defense mechanism for the host body that kills pathogens, bacterial and viral agents without side effects, but studies have shown that NETs play an important role in the pathogenesis of diseases such as autoimmune diseases and can cause tissue damage.Materials and method: Published studies between ۲۰۰۰ and ۲۰۲۱ examining the role of neutrophil extracellular traps in autoimmune diseases were identified by searching the Cochrane, PubMed, and Google Scholar databases.Results: Out of ۴۰۲ studies screened and out of ۱۶۳ studies including, ۳۴ cross-sectional studies, ۵۰ clinical trials, ۵۴ in vitro studies and ۲۵ correlation studies were used. Evidence suggests that NETs are involved in autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus )SLE), and psoriasis.
Rheumatoid arthritis is chronic inflammatory disease. Immune-stimulating molecules such as autoantibodies in the peripheral blood of patients with rheumatoid arthritis exacerbate NET formation. Excessive NET formation produces the histones citH۲A, citH۲B and citH۴, and the secretion of multiple cytokines causes joint damage. Lupus is an autoimmune syndrome that is associated with inflammation and involvement of the limbs. People with lupus can block DNase۱ access to NETs due to the presence of Dnase۱ inhibitors, and these patients have little ability to break down NETs, and large amounts of NET cause tissue damage and eventually SLE disease.
Psoriasis is a chronic skin disease that can be detected by red or silver skin lesions on the surface of the skin. Studies have shown that there is a large amount of NET in the peripheral blood and skin of these people, and the level of NETs is associated with the severity of the disease. IL-۱۷ plays a major role in the pathogenesis of psoriasis. Thus, NETs may be involved in the pathogenesis of psoriasis through IL-۱۷.Conclusion: Literature review well shows the role of the NETs in the process of autoimmunity and involvement in pathogenicity of autoimmune diseases.