IL2 and Behcet disease: In patients with BD, elevated levels of cytokines—including tumor necrosis factor receptor 1 (TNFR1), tumor necrosis factor-alpha (TNF-α), interferon (IFN), and interleukins 2, 4, 6, 10, and 17 (IL-2, IL-4, IL-6, IL-10, IL-17)—have been documented [16–21].