Figure 7. Effect of IL-22BP on the suppression of IL-22 activity in vivo.
(A) Expression levels of IL-22BP (ratio of IL-22BP/β-actin) in the colonic LP at days 0 (normal), 4 (acute phase), and 8 (recovery phase) of DSS colitis are shown. (B–F) Local IL-22BP gene delivery was performed in the proximal part of the colon, and the mice were subsequently treated with 3% DSS on the third day after the delivery. DSS treatment was terminated at day 5 after initiation, and mice were sacrificed at day 8. Expression of IL-22BP in the distal (noninjected site) and proximal (injected site) colons of mice with mock or IL-22BP gene delivery is shown (B). CECs were freshly isolated from DSS-treated WT mice that had received local gene delivery of mock or IL-22BP vector in the proximal colon. Protein lysates from the freshly isolated CECs were subjected to immunoblot with anti–phospho-STAT3 Abs (C). After stripping the Abs, the membrane was reprobed with anti-STAT3 Abs (C). The proximal colon of mock (left panel) or IL-22BP (right panel) gene–delivered mice was subjected to Alcian blue staining (D). Significant reduction of goblet cells (blue) is observed in the colon of IL-22BP–delivered mice as compared with that of mock-delivered mice. Ulceration is indicated by arrow. Original magnification, ×4. Averages of goblet cells/field in the noninjected (distal colon) and injected (proximal colon) site are shown in E. Disease score in the proximal colon (injected site) is summarized in F. *P < 0.05; **P < 0.005; ***P < 0.001.