IL18 and Behcet disease: Many studies have shown higher levels of Th1-type proinflammatory cytokines, including TNF-α, interferon- (IFN-) c, IL-2, IL-12, and IL-18, and others demonstrated high levels of IL-1, IL-6, IL-8, IL-10, soluble IL-2 receptor (sIL-2R), IFN-c, and TNF-α in BD, indicating mixed Th1- and Th2-type immune response responsible for the higher degree of immune activity in BD [3, 25].