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An antibiotic-responsive mouse model of fulminant ulcerative colitis.

Kang SS, Bloom SM, Norian LA, Geske MJ, Flavell RA, Stappenbeck TS, Allen PM - PLoS Med. (2008)

Bottom Line: Pathogenesis was driven by uncontrolled production of proinflammatory cytokines resulting in large part from T cell activation.The disease process could be significantly ameliorated by administration of antibodies against IFNgamma and TNFalpha and was completely inhibited by a combination of broad-spectrum antibiotics.This model system will be useful in the future to explore the microbial factors that induce immune activation and characterize how these interactions produce disease.

View Article: PubMed Central - PubMed

Affiliation: Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, United States of America.

ABSTRACT

Background: The constellation of human inflammatory bowel disease (IBD) includes ulcerative colitis and Crohn's disease, which both display a wide spectrum in the severity of pathology. One theory is that multiple genetic hits to the host immune system may contribute to the susceptibility and severity of IBD. However, experimental proof of this concept is still lacking. Several genetic mouse models that each recapitulate some aspects of human IBD have utilized a single gene defect to induce colitis. However, none have produced pathology clearly distinguishable as either ulcerative colitis or Crohn's disease, in part because none of them reproduce the most severe forms of disease that are observed in human patients. This lack of severe IBD models has posed a challenge for research into pathogenic mechanisms and development of new treatments. We hypothesized that multiple genetic hits to the regulatory machinery that normally inhibits immune activation in the intestine would generate more severe, reproducible pathology that would mimic either ulcerative colitis or Crohn's disease.

Methods and findings: We generated a novel mouse line (dnKO) that possessed defects in both TGFbetaRII and IL-10R2 signaling. These mice rapidly and reproducibly developed a disease resembling fulminant human ulcerative colitis that was quite distinct from the much longer and more variable course of pathology observed previously in mice possessing only single defects. Pathogenesis was driven by uncontrolled production of proinflammatory cytokines resulting in large part from T cell activation. The disease process could be significantly ameliorated by administration of antibodies against IFNgamma and TNFalpha and was completely inhibited by a combination of broad-spectrum antibiotics.

Conclusions: Here, we develop to our knowledge the first mouse model of fulminant ulcerative colitis by combining multiple genetic hits in immune regulation and demonstrate that the resulting disease is sensitive to both anticytokine therapy and broad-spectrum antibiotics. These findings indicated the IL-10 and TGFbeta pathways synergize to inhibit microbially induced production of proinflammatory cytokines, including IFNgamma and TNFalpha, which are known to play a role in the pathogenesis of human ulcerative colitis. Our findings also provide evidence that broad-spectrum antibiotics may have an application in the treatment of patients with ulcerative colitis. This model system will be useful in the future to explore the microbial factors that induce immune activation and characterize how these interactions produce disease.

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dnKO Mice Fail to Thrive and Waste Rapidly Because of a Fatal, 100% Penetrant Disease Process Localized to the Cecum and Colon(A) Plot of the average weight/group versus time for WT (n = 4), dnTGFβRII (n = 4), IL-10R2−/− (n = 5), and dnKO (n = 11) mice. All mice were weighed two or three times per week from 3 to 18 wk of age. Error bars were omitted for the sake of clarity. In all cases the experimental error was ≤ 8% of the mean value. Individual mice died or were humanely killed when their weight reached ≤ 70% of their maximal weight. The line representing dnKO average weight terminates with the death of the final dnKO mouse.(B) Whole-mount images of the mucosal surface of the descending colon from 4- to 5-wk-old WT, dnTGFβRII, IL-10R2−/−, and dnKO mice. The cecum and entire colons were harvested, dissected, opened, pinned in Bouin's fixative, and examined for gross morphology. The dnKO mice all contained major pathologic alterations including severe ulceration (e.g., red arrow) and mucosal thickening in the cecum, descending colon, and rectum (**), as well as minor alterations (*) in the ascending colon.
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pmed-0050041-g001: dnKO Mice Fail to Thrive and Waste Rapidly Because of a Fatal, 100% Penetrant Disease Process Localized to the Cecum and Colon(A) Plot of the average weight/group versus time for WT (n = 4), dnTGFβRII (n = 4), IL-10R2−/− (n = 5), and dnKO (n = 11) mice. All mice were weighed two or three times per week from 3 to 18 wk of age. Error bars were omitted for the sake of clarity. In all cases the experimental error was ≤ 8% of the mean value. Individual mice died or were humanely killed when their weight reached ≤ 70% of their maximal weight. The line representing dnKO average weight terminates with the death of the final dnKO mouse.(B) Whole-mount images of the mucosal surface of the descending colon from 4- to 5-wk-old WT, dnTGFβRII, IL-10R2−/−, and dnKO mice. The cecum and entire colons were harvested, dissected, opened, pinned in Bouin's fixative, and examined for gross morphology. The dnKO mice all contained major pathologic alterations including severe ulceration (e.g., red arrow) and mucosal thickening in the cecum, descending colon, and rectum (**), as well as minor alterations (*) in the ascending colon.

Mentions: We bred dnTGFβRII mice with IL-10R2−/− mice to generate a novel mouse strain, the dnTGFβRII × IL-10R2−/− (dnKO), which has impaired TGFβRII and IL-10R2 signaling in the T cell compartment and deficiencies in IL-10R2 dependent signaling in all cells. Total body weights of dnKO and controls (consisting of WT, dnTGFβRII, and IL-10R2−/− mice) showed that dnKO mice failed to thrive by 3–4 wk and demonstrated rapid weight loss culminating in death as compared to all controls by 4–6 wk (Figure 1A). This phenotype was 100% penetrant in dnKO mice, and no apparent gender difference in weight loss was observed (unpublished data). These data indicate that the kinetics of disease induction was significantly accelerated through the combination of two separate genetic deficiencies.


An antibiotic-responsive mouse model of fulminant ulcerative colitis.

Kang SS, Bloom SM, Norian LA, Geske MJ, Flavell RA, Stappenbeck TS, Allen PM - PLoS Med. (2008)

dnKO Mice Fail to Thrive and Waste Rapidly Because of a Fatal, 100% Penetrant Disease Process Localized to the Cecum and Colon(A) Plot of the average weight/group versus time for WT (n = 4), dnTGFβRII (n = 4), IL-10R2−/− (n = 5), and dnKO (n = 11) mice. All mice were weighed two or three times per week from 3 to 18 wk of age. Error bars were omitted for the sake of clarity. In all cases the experimental error was ≤ 8% of the mean value. Individual mice died or were humanely killed when their weight reached ≤ 70% of their maximal weight. The line representing dnKO average weight terminates with the death of the final dnKO mouse.(B) Whole-mount images of the mucosal surface of the descending colon from 4- to 5-wk-old WT, dnTGFβRII, IL-10R2−/−, and dnKO mice. The cecum and entire colons were harvested, dissected, opened, pinned in Bouin's fixative, and examined for gross morphology. The dnKO mice all contained major pathologic alterations including severe ulceration (e.g., red arrow) and mucosal thickening in the cecum, descending colon, and rectum (**), as well as minor alterations (*) in the ascending colon.
© Copyright Policy
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC2270287&req=5

pmed-0050041-g001: dnKO Mice Fail to Thrive and Waste Rapidly Because of a Fatal, 100% Penetrant Disease Process Localized to the Cecum and Colon(A) Plot of the average weight/group versus time for WT (n = 4), dnTGFβRII (n = 4), IL-10R2−/− (n = 5), and dnKO (n = 11) mice. All mice were weighed two or three times per week from 3 to 18 wk of age. Error bars were omitted for the sake of clarity. In all cases the experimental error was ≤ 8% of the mean value. Individual mice died or were humanely killed when their weight reached ≤ 70% of their maximal weight. The line representing dnKO average weight terminates with the death of the final dnKO mouse.(B) Whole-mount images of the mucosal surface of the descending colon from 4- to 5-wk-old WT, dnTGFβRII, IL-10R2−/−, and dnKO mice. The cecum and entire colons were harvested, dissected, opened, pinned in Bouin's fixative, and examined for gross morphology. The dnKO mice all contained major pathologic alterations including severe ulceration (e.g., red arrow) and mucosal thickening in the cecum, descending colon, and rectum (**), as well as minor alterations (*) in the ascending colon.
Mentions: We bred dnTGFβRII mice with IL-10R2−/− mice to generate a novel mouse strain, the dnTGFβRII × IL-10R2−/− (dnKO), which has impaired TGFβRII and IL-10R2 signaling in the T cell compartment and deficiencies in IL-10R2 dependent signaling in all cells. Total body weights of dnKO and controls (consisting of WT, dnTGFβRII, and IL-10R2−/− mice) showed that dnKO mice failed to thrive by 3–4 wk and demonstrated rapid weight loss culminating in death as compared to all controls by 4–6 wk (Figure 1A). This phenotype was 100% penetrant in dnKO mice, and no apparent gender difference in weight loss was observed (unpublished data). These data indicate that the kinetics of disease induction was significantly accelerated through the combination of two separate genetic deficiencies.

Bottom Line: Pathogenesis was driven by uncontrolled production of proinflammatory cytokines resulting in large part from T cell activation.The disease process could be significantly ameliorated by administration of antibodies against IFNgamma and TNFalpha and was completely inhibited by a combination of broad-spectrum antibiotics.This model system will be useful in the future to explore the microbial factors that induce immune activation and characterize how these interactions produce disease.

View Article: PubMed Central - PubMed

Affiliation: Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, United States of America.

ABSTRACT

Background: The constellation of human inflammatory bowel disease (IBD) includes ulcerative colitis and Crohn's disease, which both display a wide spectrum in the severity of pathology. One theory is that multiple genetic hits to the host immune system may contribute to the susceptibility and severity of IBD. However, experimental proof of this concept is still lacking. Several genetic mouse models that each recapitulate some aspects of human IBD have utilized a single gene defect to induce colitis. However, none have produced pathology clearly distinguishable as either ulcerative colitis or Crohn's disease, in part because none of them reproduce the most severe forms of disease that are observed in human patients. This lack of severe IBD models has posed a challenge for research into pathogenic mechanisms and development of new treatments. We hypothesized that multiple genetic hits to the regulatory machinery that normally inhibits immune activation in the intestine would generate more severe, reproducible pathology that would mimic either ulcerative colitis or Crohn's disease.

Methods and findings: We generated a novel mouse line (dnKO) that possessed defects in both TGFbetaRII and IL-10R2 signaling. These mice rapidly and reproducibly developed a disease resembling fulminant human ulcerative colitis that was quite distinct from the much longer and more variable course of pathology observed previously in mice possessing only single defects. Pathogenesis was driven by uncontrolled production of proinflammatory cytokines resulting in large part from T cell activation. The disease process could be significantly ameliorated by administration of antibodies against IFNgamma and TNFalpha and was completely inhibited by a combination of broad-spectrum antibiotics.

Conclusions: Here, we develop to our knowledge the first mouse model of fulminant ulcerative colitis by combining multiple genetic hits in immune regulation and demonstrate that the resulting disease is sensitive to both anticytokine therapy and broad-spectrum antibiotics. These findings indicated the IL-10 and TGFbeta pathways synergize to inhibit microbially induced production of proinflammatory cytokines, including IFNgamma and TNFalpha, which are known to play a role in the pathogenesis of human ulcerative colitis. Our findings also provide evidence that broad-spectrum antibiotics may have an application in the treatment of patients with ulcerative colitis. This model system will be useful in the future to explore the microbial factors that induce immune activation and characterize how these interactions produce disease.

Show MeSH
Related in: MedlinePlus