Fig 1: Small intestinal organoids from autoimmune-prone mice downregulate gut barrier molecules upon exposure to E. gallinarum. Ileum tissue was dissected from 12-week-old (NZW x BXSB)F1 mice. Crypts were isolated and cultured for 7 days in IntestiCult Organoid Growth Medium (STEMCELL Technologies) and Matrigel Matrix (Corning). On day 7, heat-killed E. gallinarum (EG) or EG RNA, as prepared in ref. 5, or medium was added to the organoid cultures (n = 3) for 1.5, 3, 6, and 12 h. RNA was extracted and RT-qPCR performed as described in ref. 5. RNA expression of the barrier molecules claudin-3 and claudin-5, as well as the mucus protein mucin-2, were quantified in relation to actin. Blue lines, media alone; red lines, EG lysate; green lines, EG RNA. Data are presented as mean ± SD in (a) to (c); *P < 0.05, **P < 0.01, ***P < 0.001; ANOVA followed by Bonferroni multiple-comparisons test.