TNF and clostridium difficile infection: Cytokines: interleukin 8 (IL-8), interleukin 1β (IL-1β), interleukin 6 (IL-6), tumor necrosis factor α (TNFα), interferon γ (IFN γ), and leukotriene B4 also play an important part in CDI pathogenesis [2,3].