Figure 1
Adora2b (A2B adenosine receptor)-deficient mice experience early onset of acute colitis. Gender-, age-, and weight-matched Adora2b-deficient mice (Adora2b−/−) or C57BL/6 wild-type controls (Adora2b+/+) were exposed to dextran sulfate sodium (DSS) (3–3.5%) over a time course of 7 days. (a) Daily weight measurements were obtained for each group of mice. (b) Following killing, colons were harvested and measured. Results are representative of one to two independent experiments with n=4–13 mice per group. (c) Mice were administered FITC (fluorescein isothiocyanate)-dextran by oral gavage (0.6 mg g−1 at 80 mg ml−1) 4 h before killing. Serum was harvested at killing (days 1 and 3 after DSS) and fluoresence measurement was used to determine FITC levels; n=2–9 mice per group from one independent experiment per time point. (d) Following colon harvest at day 7 after DSS, colonic lamina propria leukocytes were isolated and flow cytometry determined the frequency of GR-1+ (neutrophils), SiglecF+ (eosinophils), F4/80+ (macrophages), and MHCII+CD11cHi (dendritic cells) cells. Actual cell number for each cell type was calculated based on the frequency of cell type multiplied by cell counts following organ harvest. Results are representative of one independent experiment with n=3–4 mice per group. (e) Representative histological sections from whole colon of Adora2b−/− or Adora2b+/+ mice harvested following 7 days DSS. Bar=100 μm; images acquired at original magnification × 10. (f) Blinded histological analysis of whole colon from each group following DSS. Data represent 8–10 mice per group. Unless stated otherwise, results are representative of two independent experiments with 3–10 mice per group and are displayed as mean±s.e.m. Two-way analysis of variance (ANOVA) with post hoc Bonferroni t-test was used to determine statistical weight change, but in all other cases Student’s t-test was used. *P<0.5; **P<0.001; ***P<0.0001.
