Volume 121, Issue 6, Pages 1372-1379 (December 2001) Blockade of endogenous IL-18 ameliorates TNBS-induced colitis by decreasing local TNF-α production in mice  Tessa Ten Hove, Anne Corbaz, Hagit Amitai, Shuki Aloni, Ilana Belzer, Pierre Graber, Paul Drillenburg, Sander J.H. van Deventer, Yolande Chvatchko, Anje A. te Velde  Gastroenterology  Volume 121, Issue 6, Pages 1372-1379 (December 2001) DOI: 10.1053/gast.2001.29579 Copyright © 2001 American Gastroenterological Association Terms and Conditions

Fig. 1 rhIL-18BPa treatment impaired body weight loss. Body weight was recorded daily from day 1 to day 10. The change in weight is expressed as percentage of body weight from day 1, and data represent means ± SEM for 8 mice per group. (A) Saline-instilled mice treated with saline (◊) or 50 μg rhIL-18BPa (■); TNBS mice treated with saline (▵), 12.5 μg rhIL-18BPa (×), 25 μg rhIL-18BPa (○), or 50 μg rhIL-18BPa (2). (B) Control saline-instilled mice were injected intraperitoneally daily with saline (2) and 200 μg rhIL-18BPa (●). TNBS mice were injected intraperitoneally daily with saline (◊) and 200 μg rhIL-18BPa (▴). Results are representative of 2 experiments. Gastroenterology 2001 121, 1372-1379DOI: (10.1053/gast.2001.29579) Copyright © 2001 American Gastroenterological Association Terms and Conditions

Fig. 2 rhIL-18BPa treatment reduces disease parameters in TNBS-induced colitis. (A) Weight of the last 6 cm of the colon. (B) Total number of cells present in the caudal lymph node. (C) Percentage of CD4+/CD69+ cells isolated from spleen. Data represent means ± SEM, *P < 0.05. 2, Saline-treated TNBS mice (n = 8); ■, rhIL-18BPa–treated TNBS mice at 8 mg/kg (n = 8). Results are representative of 2 experiments. Gastroenterology 2001 121, 1372-1379DOI: (10.1053/gast.2001.29579) Copyright © 2001 American Gastroenterological Association Terms and Conditions

Fig. 3 rhIL-18BPa treatment attenuates colonic inflammation. H&E staining of the colons of mice with TNBS-induced colitis. (A) TNBS mouse treated with saline. Common pathologic features such as edema, ulceration, influx of cells, and crypt loss can be seen in saline-treated mice with colitis. (B) TNBS mouse treated with 8 mg/kg rhIL-18BPa. Inflammation is present, but there is significantly less inflammation, fewer cells infiltrate the area of inflammation, and ulcerations are absent. Gastroenterology 2001 121, 1372-1379DOI: (10.1053/gast.2001.29579) Copyright © 2001 American Gastroenterological Association Terms and Conditions

Fig. 4 Caudal lymph node and spleen cells were stimulated in vitro with anti-CD3 and anti-CD28 antibodies. After 48 hours, supernatants were analyzed by ELISA for IFN-γ and TNF-α contents. 2, Saline-treated TNBS mice (n = 8); ■, rhIL-18BP–treated TNBS mice at 8 mg/kg (n = 8), means ± SEM. TNF-α production by (A) stimulated caudal lymph node cells and (B) spleen cells. IFN-γ production by (C) stimulated caudal lymph node cells and (D) spleen cells. Results are representative of 2 experiments. Gastroenterology 2001 121, 1372-1379DOI: (10.1053/gast.2001.29579) Copyright © 2001 American Gastroenterological Association Terms and Conditions

Fig. 5 Therapeutic potential of rhIL-18BPa treatment on days 8 and 9. (A) Weight of the last 6 cm of the colon. (B) Total colitis score. Data represent means ± SEM. *P ≤ 0.05. 2, Saline-treated TNBS mice (n = 8); ■, rhIL-18BPa–treated (days 8 and 9) TNBS mice at 8 mg/kg (n = 8). Gastroenterology 2001 121, 1372-1379DOI: (10.1053/gast.2001.29579) Copyright © 2001 American Gastroenterological Association Terms and Conditions