TNF and inflammatory bowel disease: Tumor necrosis factor α (TNFα), which is at the top of the cytokine cascade, can be released by macrophages and stimulates the nuclear factor (NF)-κB signaling pathway which plays a crucial role in the pathogenesis of IBD (Neurath, 2014; de Souza and Fiocchi, 2016; Park and Jeen, 2018).