The inflammatory nature of the infection means that C. rodentium interactions with IECs take place in an environment rich in cytokines (e.g., interleukin-18 [IL-18], IL-22, IL-6, IL-1β, tumor necrosis factor alpha [TNF-α], interferon-γ) and infiltrating immune cells (Collins et al., 2014). The gene discussed is TNF; the disease is infection.