IL-37 (IL-1F7)

The IL-1 family is comprised of 11 structurally related ligands, including recently re-named IL-37 (IL-1F7), which acts as a modulator of the immune response. Reduction of IL-37 synthesis in PBMCs leads to increased production of proinflammatory cytokines including IL-1 alpha, IL-1 beta, IL-6 and TNF- alpha. The role of IL-37 as an inhibitor of the innate inflammatory response is also corroborated by the observation that it is highly expressed in synovial tissue from patients with rheumatoid arthritis. Full length IL-37 resides primarily in the cytoplasm, but after activation through cleavage by CASP1, it can translocate to the nucleus where it exerts its activity by direct interaction with SMAD3. Recombinant Human IL-37 is a 19.4 kDa protein consisting of 174 amino acids, corresponding to the mature activated form of IL-37.