Although TNFα is a pivotal factor for the initiation of the inflammatory response, the absence of TNFα is deleterious in murine models of inflammatory disorders including experimental autoimmune encephalomyelitis25 and dextran sodium sulfate-induced colitis.26 The shortcomings of the aforementioned murine models needed to be addressed in order to investigate the role of TNFα in UC non-responders. This evidence concerns the gene TNF and colitis.