IL33 and vasculitis: Polymorphisms in the IL-1 gene cluster (namely IL-1A 2889C and IL-1B +5887T haplotype) are associated with an increased susceptibility to vasculitis, including BS, and other cytokines belonging to the IL-1 family (including IL-1α and IL-33) are known to be involved in the pathogenesis of BS [36,37,38], whereas little is known about the role of IL-36 in this disease.