TRAF3 and colitis: Like TRAF3, TRAF2 negatively regulate induction of proinflammatory cytokines by the TLR ligands LPS and polyIC as well as by the cytokine IL-1β, and the myeloid cell-conditional TRAF2 knockout (TRAF2-MKO) mice are hypersensitive to colitis induction in the DSS model (126).