Commensal intestinal microbes contribute to TNF-induced toxicity in A20^IEC-KO mice. (A) Body temperature after mouse TNF challenge of A20^IEC-KO mice and control littermate mice (WT) either untreated (IEC-KO, n = 6; WT, n = 5) or treated (IEC-KO, n = 6; WT, n = 8) with broad-spectrum antibiotics. (B) H&E histology on sections from distal ileum 0 and 7 h after i.p. injection of mouse TNF in control (WT) and A20^IEC-KO mice treated with antibiotics. Bottom images are magnifications of rectangles in top images. Bars: (top) 100 µm; (bottom) 75 µm. (C) H&E histology on liver samples 0 and 7 h after TNF injection in control (WT) and A20^IEC-KO mice either untreated or treated with antibiotics. Bars, 75 µm. Data are representative of two independent experiments. Error bars represent SEM.