During the mid-point of infection, the host response to C. rodentium is primarily Th1/Th17 driven, whereas cytokines of “Th2/anti-inflammatory” type appear during clearance: interferon gamma (Ifn-γ) and interleukin (IL) Il-12 become up-regulated throughout infection whereas Il-4, tumor necrosis factor alpha (Tnf-α) and Il-6 mRNA become upregulated during clearance only [1]. The gene discussed is TNF; the disease is infection.