IL1R1 and infection: IL-1R8 is highly expressed in gut epithelium and this has been linked to tuning of TLR reactivity against commensal bacteria; IL-1R8-deficiency in mice infected with Citrobacter rodentium was associated with exaggerated IL-1R1 signaling-dependent gut inflammation, causing a severe loss of commensal bacteria and facilitated secondary infection by Salmonella typhimurium (139).