Figure 3. The deficiency of Areg induces less severe intestinal fibrosis.

(A-G) WT mice and Areg^−/− mice (n=5/group) were administered with 3 cycles of DSS insults. In each cycle, mice were given 2.0% DSS (w/v) in drinking water for 7 days and control drinking water for 7 days. (A) Colitis severity was measured by histopathology and pathological scores. (B-D) Col1a1, Col6a1, and Col6a3 levels in colonic tissues were measured by RT-PCR. (E-G) Colon tissues were stained with (E) Sirius Red and (F-G) immunofluorescence. Collagen layer thickness, Collagen I thickness, and αSMA layer thickness were analyzed. (H-J) WT and Areg^−/− T cells were cultured under Th17 conditions for 5 days and then transferred into Tcrβxδ^−/− mice (n=5/group). The mice were sacrificed 4 weeks later. (H) Colitis severity was measured by histopathology and pathological scores. (I-J) Intestinal fibrosis was determined by Collagen I staining (I) and αSMA staining (J). Representative data from 2 independent experiments with similar results. (A and H) Mann–Whitney U test; (B-G and I-J) unpaired Student’s t-test. *p < .05; **p < .01.