IFNG and infection: IFN-γ production by macrophages is promoted by IL-18 when Rag2-/-γc−/− mice are infected by C. parvum (Choudhry et al., 2012), and IFN-γ-/- mice have fewer macrophages and T cells recruited to the gut accompanying an inability to recover from infection (Lacroix-Lamande et al., 2002).