TNF and Behcet disease: Berk et al. (2011) however, showed that in the early stages of the disorder, the anti-inflammatory cytokine IL-10 is elevated and its level decreases with the progression of BD, while pro-inflammatory IL-6 and TNF-α are elevated at the onset of the disease and persist over time which may suggest that persistent inflammation and depletion of anti-inflammatory mechanisms causes the progression of BD [63].