Volume 141, Issue 5, Pages 1821-1831 (November 2011) Retinoic Acid Attenuates Ileitis by Restoring the Balance Between T-Helper 17 and T Regulatory Cells  Colm B. Collins, Carol M. Aherne, Douglas Kominsky, Eóin N. McNamee, Matthew D.P. Lebsack, Holger Eltzschig, Paul Jedlicka, Jesús Rivera–Nieves  Gastroenterology  Volume 141, Issue 5, Pages 1821-1831 (November 2011) DOI: 10.1053/j.gastro.2011.05.049 Copyright © 2011 AGA Institute Terms and Conditions

Figure 1 Proportion of CD103+ DCs decreased during late disease in TNFΔARE LP. (A) Flow cytometric analysis of CD103+ DCs in the spleen, MLNs, and LP of 4- and 20-week-old TNFΔARE mice compared with WT littermates. Mean ± SEM of n ≥3 individual mice for each genotype and time point; *P < .05. (B) Representative plots showing the gating strategy for identifying CD103+ DCs from the MLNs and LP of 20-week-old WT mice, with overlaid histograms for CD103 on DCs from a CD103-deficient mouse of matched age. (C) Representative histograms of CD103 expression on DCs from MLNs and LP of 20-week-old WT and TNFΔARE mice. Gastroenterology 2011 141, 1821-1831DOI: (10.1053/j.gastro.2011.05.049) Copyright © 2011 AGA Institute Terms and Conditions

Figure 2 Decreased RALDH2 expression in CD103+ and CD103Neg DCs from 4- and 20-week-old TNFΔARE mice compared with WT littermates. RALDH2 mRNA expression in isolated CD103+ and CD103Neg CD11chi/MHCII+ DCs from MLNs and LP of 4- and 20-week-old WT and TNFΔARE mice. Mean ± SEM from 3 separate experiments requiring pooled organs from 4 to 11 mice/strain/experiment. *P < .05, ***P < .001. Gastroenterology 2011 141, 1821-1831DOI: (10.1053/j.gastro.2011.05.049) Copyright © 2011 AGA Institute Terms and Conditions

Figure 3 Increased percentage of Tregs in the spleen, MLNs, and LP of 20-week-old TNFΔARE mice compared with WT littermates. (A) The percentage of CD4+/CD25+/FoxP3+ cells in the spleen, MLNs, and ileal LP of TNFΔARE mice compared with WT mice at 20 weeks of age. Mean ± SEM for n ≥ 5 individual mice/strain for each time point; *P < .05, ***P < .001. (B) Representative dot plots showing expression of CD4+/CD25+/FoxP3+ T lymphocytes from the LP of 20-week-old TNFΔARE mice and WT littermates. Gastroenterology 2011 141, 1821-1831DOI: (10.1053/j.gastro.2011.05.049) Copyright © 2011 AGA Institute Terms and Conditions

Figure 4 Dynamic changes in RALDH expression in IECs likely mediated by TNF overproduction and RA deficiency. (A) Quantification of RALDH3 mRNA from IEC fractions from 4- and 20-week-old TNFΔARE mice compared with WT by real-time reverse-transcription PCR. Mean ± SEM, n = 7/strain, *P < .05. (B) Expression of RALDH1, 2, and 3 mRNA transcripts in IEC fractions from 20-week-old mice, mean ± SEM, n = 7/strain. *P < .05. (C) Analysis of RALDH3 mRNA expression from MODE-K cells cultured for 48 hours treated in triplicate with 1 μmol/L RA, 10 ng/mL TNF, 1 μmol/L LE540, or 1 μmol/L AM580 stimulation or untreated for 24 hours followed by treatment with 1 μmol/L LE540 for 24 hours (NT/LE). Mean ± SEM of 4 individual experiments, *P ≤ .05, **P < .01, ***P ≤ .001.). Gastroenterology 2011 141, 1821-1831DOI: (10.1053/j.gastro.2011.05.049) Copyright © 2011 AGA Institute Terms and Conditions

Figure 5 RA supplementation significantly attenuated chronic ileitis in vivo. (A) Inflammatory indices from ilea of 20-week-old TNFΔARE mice treated with RA intraperitoneally twice weekly for 2 weeks or vehicle were assessed as described.28 Mean ± SEM, n = 8/treatment group, *P < .05, **P < .01. (B) Representative H&E micrographs of vehicle- and RA-treated ilea of 20-week-old TNFΔARE mice (original magnification 10×, bars = 100 μm). Gastroenterology 2011 141, 1821-1831DOI: (10.1053/j.gastro.2011.05.049) Copyright © 2011 AGA Institute Terms and Conditions

Figure 6 RA shifts regulatory and effector balance of T cells in the inflamed ileum. (A) Frequency of CD4+/CD25+/FoxP3+ Tregs and CD4+/IL-17+ Th17 cells in indicated organs isolated from vehicle- or RA-treated 20-week-old TNFΔARE mice. (B) Dot plots showing percentages of CD4+/CD25+/FoxP3+ and CD4+/IL-17+ cells from vehicle- and RA-treated mice. Representative data from 3 independent experiments (C) MCP-1, IL-1β, IL-10, and IL-17A from 24-hour cultures of unfractionated CD3/28 stimulated lymphocytes, measured using the multiplex cytokine analysis system from Quansys Biosciences. Mean ± SEM for n ≥3 mice/group. *P ≤ .05. Gastroenterology 2011 141, 1821-1831DOI: (10.1053/j.gastro.2011.05.049) Copyright © 2011 AGA Institute Terms and Conditions

Figure 7 RA deficiency in whole intestinal tissue of inflamed mice. (A) Expression of RALDH1, 2, and 3 mRNA in ileal tissue from 20-week-old TNFΔARE mice compared with WT littermates. Mean ± SEM, n = 7/genotype, *P ≤ .05. (B) Coulometric analysis of whole tissue extracts from WT and TNFΔARE mice showed a significant reduction in RA levels in inflamed mice ilea compared with WT controls. Mean ± SEM, n = 5/genotype, *P < .05. (C) Representative scanning electron micrographs of ilea from 20-week-old WT and TNFΔARE mice (original magnification 80×). Gastroenterology 2011 141, 1821-1831DOI: (10.1053/j.gastro.2011.05.049) Copyright © 2011 AGA Institute Terms and Conditions

Supplementary Figure 1 Gastroenterology 2011 141, 1821-1831DOI: (10.1053/j.gastro.2011.05.049) Copyright © 2011 AGA Institute Terms and Conditions

Supplementary Figure 2 Gastroenterology 2011 141, 1821-1831DOI: (10.1053/j.gastro.2011.05.049) Copyright © 2011 AGA Institute Terms and Conditions

Supplementary Figure 3 Gastroenterology 2011 141, 1821-1831DOI: (10.1053/j.gastro.2011.05.049) Copyright © 2011 AGA Institute Terms and Conditions

Supplementary Figure 4 Gastroenterology 2011 141, 1821-1831DOI: (10.1053/j.gastro.2011.05.049) Copyright © 2011 AGA Institute Terms and Conditions

Supplementary Figure 5 Gastroenterology 2011 141, 1821-1831DOI: (10.1053/j.gastro.2011.05.049) Copyright © 2011 AGA Institute Terms and Conditions

Supplementary Figure 6 Gastroenterology 2011 141, 1821-1831DOI: (10.1053/j.gastro.2011.05.049) Copyright © 2011 AGA Institute Terms and Conditions

Supplementary Figure 7 Gastroenterology 2011 141, 1821-1831DOI: (10.1053/j.gastro.2011.05.049) Copyright © 2011 AGA Institute Terms and Conditions