Crohn Disease: Scheinin T

Scheinin T, Butler DM, Salway F, Scallon B, Feldmann M. · Fourth Department of Surgery, University of Helsinki, Helsinki, Finland. · Clin Exp Immunol. · Pubmed #12823276 links to  free full text

Abstract: Advances in understanding pathogenesis and developing new therapies are hastened by the use of effective animal models of disease. In inflammatory bowel disease, such as Crohn's disease, a variety of models have been used, including the IL-10 knockout mouse. However, in order to be truly valuable, the models need to respond to existing therapy in a way which resembles the human disease. In the light of recent developments, in which refractory Crohn's disease responds well to anti-TNF antibody therapy, we set out to validate the IL-10 knockout model of Crohn's disease by examining its response to anti-TNF therapy. We developed a new scoring system for IL-10 knockout mice, similar to the Crohn's Disease Activity Index in humans, analysed stool samples for cytokines and compared the findings with histology. We found that anti-TNF antibody therapy starting at 4 weeks markedly ameliorated the disease, as judged by the clinical score or by histological analysis of the gut. Furthermore, analysis of stool samples for cytokines revealed a marked diminution of inflammatory cytokines, adding a further accurate measure of the improvement. This model may thus be useful for evaluating other therapeutic modalities of relevance to Crohn's disease.

Lindsay JO, Ciesielski CJ, Scheinin T, Brennan FM, Hodgson HJ. · Kennedy Institute of Rheumatology Division, Imperial College School of Medicine, London, UK. · Gut. · Pubmed #12584217 links to  free full text

Abstract: INTRODUCTION: Interleukin 10 knockout (IL-10-/-) mice spontaneously develop a Th1 T cell mediated colitis with many similarities to Crohn's disease. Daily injections of IL-10 are unable to induce remission in mice with established disease. In contrast, we have shown previously that intravenous administration of adenoviral vectors encoding IL-10 (AdvmuIL-10) induces hepatic IL-10 release and leads to long term disease suppression with profound systemic immunoregulatory changes. AIMS: To determine whether rectal delivery of AdvmuIL-10 induces localised colonic IL-10 expression without systemic immune suppression, and assess its therapeutic efficacy in IL-10-/- mice with established colitis. RESULTS: A single rectal infusion of 5 x 10(8) PFU AdvmuIL-10 to 10 week IL-10-/- mice resulted in a median level of 27.3 pg/mg IL-10 in colonic homogenates harvested one week later. IL-10-/- mice with established colitis treated with an enema of 5 x 10(8) PFU AdvmuIL-10 entered clinical and histological remission whereas empty cassette adenovirus (Adv0) or phosphate buffered saline (PBS) treated mice developed progressive disease. After four weeks, the histological score of AdvmuIL-10 treated mice (4.4 (1.5)) was significantly lower than that of Adv0 (11.1 (1.1); p<0.001) and PBS (10.9 (1.0); p<0.01) treated controls. In addition, the stool concentration of IL-1 beta over the four week experiment was significantly higher in mice treated with saline or Adv0 than in those treated with AdvmuIL-10 (p<0.01). CONCLUSION: Local AdvmuIL-10 therapy reverses colitis in IL-10-/- mice without the systemic effects seen after intravenous administration. Gene therapy strategies using adenoviral vectors encoding immunoregulatory cytokines may prove to be a potent approach to the treatment of chronic inflammatory diseases such as Crohn's disease.

Scheinin T, Böhling T, Halme L, Kontiainen S, Bjørge L, Meri S. · Department of Surgery, Surgical Hospital, University of Helsinki, Finland. · Hum Pathol. · Pubmed #10667419 No free full text.

Abstract: Without adequate protection, the cells of the human body would be susceptible to destruction by the complement system. The main defense against complement lysis is a molecule called protectin (CD59) that is widely distributed in human tissues. Because the complement system has been suggested to be involved in the pathogenesis of inflammatory bowel diseases, we examined the expression of protectin in the colonic epithelium of patients with ulcerative colitis or Crohn's disease and controls. Colorectal specimens from 6 patients with ulcerative colitis, 8 patients with Crohn's disease, and 4 controls were obtained from surgical resections. Frozen sections of the specimens were immunostained for protectin using the Bric 229 monoclonal antibody. The expression of protectin was found to be decreased in the epithelium of patients with ulcerative colitis. In patients with Crohn's disease, the epithelial expression of protectin was decreased in diseased areas of gut while the expression did not significantly differ from that in controls in macroscopically normal areas. There was no difference in the expression of protectin on vascular endothelium, mononuclear cells, or smooth muscle. The reduction in epithelial expression of protectin in patients with ulcerative colitis or Crohn's disease may render epithelial cells vulnerable to complement lysis and lead to the destruction of gut epithelium as seen typically in these diseases.

Lindsay JO, Ciesielski CJ, Scheinin T, Brennan FM, Hodgson HJ. · Kennedy Institute of Rheumatology Division, Imperial College School of Medicine, 1 Aspenlea Road, London W6 8LH, UK. · Gut. · Pubmed #12801955 links to  free full text

Abstract: INTRODUCTION: Interleukin 10 knockout (IL-10-/-) mice spontaneously develop a Th1 T cell mediated colitis with many similarities to Crohn's disease. Daily injections of IL-10 are unable to induce remission in mice with established disease. In contrast, we have shown previously that intravenous administration of adenoviral vectors encoding IL-10 (AdvmuIL-10) induces hepatic IL-10 release and leads to long term disease suppression with profound systemic immunoregulatory changes. AIMS: To determine whether rectal delivery of AdvmuIL-10 induces localised colonic IL-10 expression without systemic immune suppression, and assess its therapeutic efficacy in IL-10-/- mice with established colitis. RESULTS: A single rectal infusion of 5 x 10(8) PFU AdvmuIL-10 to 10 week IL- 10-/- mice resulted in a median level of 27.3 pg/mg IL-10 in colonic homogenates harvested one week later. IL-10-/- mice with established colitis treated with an enema of 5 x 10(8) PFU AdvmuIL-10 entered clinical and histological remission whereas empty cassette adenovirus (Adv0) or phosphate buffered saline (PBS) treated mice developed progressive disease. After four weeks, the histological score of AdvmuIL-10 treated mice (4.4 (1.5)) was significantly lower than that of Adv0 (11.1 (1.1); p<0.001) and PBS (10.9 (1.0); p<0.01) treated controls. In addition, the stool concentration of IL-1beta over the four week experiment was significantly higher in mice treated with saline or Adv0 than in those treated with AdvmuIL-10 (p<0.01). CONCLUSION: Local AdvmuIL-10 therapy reverses colitis in IL-10-/- mice without the systemic effects seen after intravenous administration. Gene therapy strategies using adenoviral vectors encoding immunoregulatory cytokines may prove to be a potent approach to the treatment of chronic inflammatory diseases such as Crohn's disease.