Although the exact cause of AOSD is unknown, aberrant activation of innate immune cells, such as neutrophils, monocytes, and macrophages, as well as excessive cytokine production, including IL-1β, IL-6, TNF-alpha (tumor necrosis factor-alpha) and IL-18 are likely to be significant contributing factors [4]. The gene discussed is IL1B; the disease is adult-onset Still disease.