NETs are highly enriched in specific autoantigens such as citrullinated proteins targeted by ACPA in patients with RA [38, 39], but they also provide stimuli to fibroblast-like synoviocytes [40], dendritic cells [41], macrophages [42], and lymphocytes [43, 44], which promote systemic and local (synovial) autoimmune responses. The gene discussed is PRTN3; the disease is rheumatoid arthritis.