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Comment on: Prospective cohort study of appendicectomy for treatment of therapy-refractory ulcerative colitis For the past three decades, the value of appendicectomy for patients with ulcerative colitis (UC) has been debated[1]. Prospective cohort study of appendicectomy for treatment of therapy-refractory ulcerative colitis. [Extracted from the article]

Background and aims. The nonsystemic steroid budesonide has been used to treat active ileocecal and ileocolonic Crohn's disease (CD). This study investigated the optimal budesonide dose using a pH-dependent release formulation. The goal of treatment was the remission of CD (CDAI <150) within 6 weeks of treatment. Patients and methods. The study was of randomized, double-blind, dose-finding design. Patients with active CD ileocolitis without steroid pretreatment were treated with 3×2 mg (n=39), 3×3 mg (n=33), or 3×6 mg (n=32) oral pH-modified released budesonide daily. Results. The remission rates after 6 weeks were 36% with 3×2 mg, 55% with 3×3 mg, and 66% with 3×6 mg. Significantly more patients were in remission while treated with 3× 6mg than with 3×2 mg budesonide/day. Subgroup analyses revealed that patients with high disease activity (CDAI ≥ 300) or ileocolonic disease with disease manifestation distal to the transverse colon responded better to the highest budesonide dose. Conclusion. Oral pH-modified released budesonide shows a dose-dependent effectiveness in patients with active ileocolonic CD. In the majority of patients 9 mg budesonide per day is sufficient. However, in patients with highly active disease or ileal disease with distal colonic manifestation higher doses of budesonide could increase the therapeutic response [ABSTRACT FROM AUTHOR]

Leucocyte recruitment to sites of intestinal inflammation is a crucial, multi-step process that leads ultimately to the accumulation of cells in the inflamed tissue. We established a new in vivo model system of experimental colitis to quantify leucocyte–endothelial cell interaction and leucocyte extravasation in the inflamed mucosa of the colon. Furthermore, we investigated the pathophysiological role of ICAM-1 in the intestinal microcirculation in vivo. Using the model of dextran sodium sulphate (DSS)-induced acute and chronic colitis in mice, in vivo microscopy was performed in the colonic submucosal postcapillary venules and the submucosal collecting venules in normal or inflamed murine colonic segments. ICAM-1 expression was blocked by an anti-ICAM-1 monoclonal antibody or by suppressing NF-κB activation by gliotoxin. Significant increases in leucocyte adhesiveness (51-fold in postcapillary venules, 30-fold in collecting venules, P < 0·01) and extravasation (6·5-fold) could be demonstrated as early as day 2 of DSS-application in acute colitis (P < 0·01). This was paralleled by increases in both the histological damage scores and myeloperoxidase activities. In chronic dextran sodium sulphate-induced colitis significant increases in leucocyte–endothelium interactions and leucocyte extravasation were observed. Blocking ICAM-1 expression with a monoclonal antibody or gliotoxin, leucocyte sticking and extravasation were significantly down-regulated in vivo compared to controls (> 70%; P < 0·01). This new model system offers the possibility to specifically assess the role of adhesion molecules in the colonic mucosa in vivo as well as to investigate and quantify the effectiveness of experimental therapeutic approaches in acute or chronic intestinal inflammation. [ABSTRACT FROM AUTHOR]

In acute DSS-induced colitis nuclear factor (NF)-κB-dependent inflammatory cytokines including IL-1 and tumour necrosis factor-alpha (TNF-α) are up-regulated. Here we examined the effects of gliotoxin, a fungal metabolite known to inhibit NF-κB activity, on cytokine production by a mouse cell system in vitro and on intestinal inflammation and NF-κB activation in vivo. In vitro gliotoxin decreased TNF-α gene expression and protein production by RAW-264.7 mouse macrophage-like cells stimulated with lipopolysaccharide. In vivo, gliotoxin treatment of mice was begun on day 3 of 5% DSS application dissolved in the drinking water and continued until day 8. Gliotoxin treatment dose-dependently down-regulated colonic inflammation as assessed histologically and in parallel there was a suppression of colonic TNF-α and IL-1α mRNA expression on day 8 as analysed by semiquantitative reverse transcriptase-polymerase chain reaction (P < 0·01). Furthermore, colonic NF-κB DNA-binding activity was increased in DSS-induced colitis and was suppressed by gliotoxin. These results demonstrate the essential role of NF-κB in DSS-induced colitis and indicate a molecular approach to the treatment of intestinal inflammatory disorders. [ABSTRACT FROM AUTHOR]

The article discusses about Crohn's disease in relation to deposition of fats. The connective and adipose tissue changes observed in patients with Crohn's disease have received only little attention from pathologists, although fat hypertrophy, fat wrapping--fat creeping upon the bowel, and creeping fat have long been recognized by surgeons as a phenomenon suitable for delineating the extent of active disease. Burril B. Crohn himself, who gave his name to this chronic inflammatory bowel disease, initially described the changes in the appearance of the mesenteric adipose tissue as a characteristic symptom of the disease.

The term virtual colonoscopy was initially coined by researcher D.J. Vinig in 1994 who demonstrated the feasibility of creating three dimensional pictures of the colon using spiral computed tomography (CT) technology. Since the term virtual colonoscopy is misleading and implies a colonoscopic procedure rather than generation of images, this methodology should be referred to as virtual colonography (VC). VC can be performed using CT or magnetic resonance imaging (MRI). In the December 2003 issue of the journal "Gut," researcher Ajaj W. and colleagues present an evaluation of a new MR colonography technique employing a water enema for contrasting and extending the colon.

A letter to the editor is presented in response to the article about glucocorticoid receptor isoform expression in inflammatory bowel disease (IBD) treatment.

The article presents a letter entitled "Adverse events in clinical trials with azathioprine and mesalamine for prevention of postoperative recurrence of Crohn's disease," by H. Herfarth, C. Tjaden and M. Lukas published within the issue. The authors comment on the study about the efficacy and side effects of azathioprine in the therapy of ulcerative colitis. The researchers presented the findings on the efficacy of azathioprine for the prevention of postoperative recurrence in Crohn's disease.

Low levels of high-density lipoprotein (HDL)-cholesterol represent an independent cardiovascular risk factor and, besides reduced physical activity, mechanisms leading to decreased HDL-cholesterol levels are not known. We aimed to test the hypothesis, that adiponectin provides a missing link between type 2 diabetes and low levels of HDL-cholesterol, independent from common metabolic risk factors. 523 patients with type 2 diabetes were investigated for adiponectin serum levels and parameters of lipid metabolism. Even after correction for age, gender, BMI and fasting insulin concentration, serum levels of adiponectin were highly significant (P<0.0001) and positively (regression analysis: r=0.86) associated with HDL-cholesterol levels in type 2 diabetes. Conclusion: adiponectin seems to predict HDL-cholesterol levels in patients with diabetes mellitus type 2. Low levels of adiponectin are associated with low levels of HDL-cholesterol independently from common metabolic risk factors and therefore represent an independent cardiovascular risk factor in type 2 diabetes. Thus, adiponectin is a potentially new drug target in the treatment of dyslipidaemia. [Copyright &y& Elsevier]

Abstract: Genomic structure, promoter region, amino acid sequence and exon-specific primer combinations of the human omentin gene are presented. Omentin mRNA expression differs between omental adipose tissue probes from patients with chronic inflammatory bowel diseases such as Crohn''s disease. Sequence comparisons revealed a 100% identity of omentin with human intelectin. Based on this, omentin might be a new adipocytokine playing a role in the defense against intestinal bacterial translocation in the context of Crohn''s disease. [Copyright &y& Elsevier]

To investigate the association of serum levels and the −2518 A→G promoter polymorphism of the gene for chemokine monocyte chemoattractant protein-1 (MCP-1), a major chemoattractant of monocytes and activated lymphocytes, with metabolic parameters as well as insulin, leptin and the cytokines tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in 534 Caucasian patients with type 2 diabetes mellitus. MCP-1 concentrations were measured by enzyme-linked immunosorbent assay. MCP-1 genotyping was performed by RFLP analysis in a subset of 426 patients. Two hundred and thirty-one (54.2%) patients were homozygous for the wildtype allele (AA), 156 (36.6%) were heterozygous (AG) and 39 (9.2%) were homozygous for the mutated allele (GG). Allelic frequency was similar to non-diabetic populations (wildtype allele A: 0.73; mutated allele G: 0.27). MCP-1 mean concentrations and percentiles were substantially higher in non-diabetic populations but were not influenced by the genotype (AA: 662.0 ± 323.0 pg/ml; AG: 730.6 ± 491.4 pg/ml; GG: 641.2 ± 323.8 pg/ml). MCP-1 serum levels and genotypes were only marginally related to hormones (insulin and leptin) and cytokines (TNF-α and IL-6). This is the first study providing MCP-1 levels, percentiles and genotype frequency in a large and representative cohort of patients with type 2 diabetes mellitus. Compared to the literature, MCP-1 levels were found to be substantially higher in patients with type 2 diabetes mellitus. In contrast, genotype frequencies were similar compared to those in non-diabetic patients and were not related to MCP-1 levels. The mechanisms behind these elevated MCP-1 serum levels in type 2 diabetes are not to be explained by simple associations with hormones, cytokines or genotypes. [ABSTRACT FROM AUTHOR]

Background. Nonocclusive mesenteric ischemia is a rare but serious disorder with a high mortality rate; causal factors include cardiac glycosides, digoxin, and digitoxin in addition to severe hypotension, decompensated heart failure, and septic shock. Case presentation. We present a patient with digitoxin intoxication who died from autopsy-confirmed ischemic gangrenous colitis. Conclusion. Despite the frequent occurrence of intoxication with cardiac glycosides nonocclusive mesenteric ischemia is a rare event. However, it should always be included as a differential diagnosis of diffuse abdominal pain in patients treated with cardiac glycosides. [ABSTRACT FROM AUTHOR]

Background: In normal mucosa, intestinal lamina propria macrophages (IMACs) maintain tolerance against food antigens and the commensal bacterial flora. Several mechanisms have been identified that mediate tolerance. The ubiquitin-proteasome system (UPS) is a large multiprotein complex that degrades cellular proteins. As the UPS may modulate immune functions of IMACs, we performed a detailed investigation of UPS expression and function under normal conditions and in cells derived from patients suffering from inflammatory bowel disease (IBD). Methods: IMACs were isolated from intestinal mucosa. mRNA expression of macrophages differentiated in vitro (i.v. MACs) and IMACs was compared by Affymetrix® oligonucleotide arrays. Quantitative Taqman-PCR was performed on five exemplary proteasomal and five ubiquitinylation genes each. Proteins were analyzed by immunohistochemistry and Western blotting. Proteasome function was assessed by a fluorimetric test. Results: Affymetrix analysis showed downregulation of mRNA expression of almost all represented proteasomal and of 22 ubiquitination-associated genes in IMACs as compared to i.v. MACs and monocytes. By quantitative PCR, up to tenfold higher mRNA expression of 10 exemplary genes of the UPS (UBE2A, UBE2D2, UBE2L6, USP14, UBB and ATPase2, β2, β5, β2i/MECL-1, β5i/LMP7) was demonstrated in i.v. MACs as compared to IMACs. Immunohistochemistry and Western blots confirmed these findings in intestinal mucosa of controls and patients suffering from diverticulitis. In contrast, a significant increase in protein amounts was found in mucosa of patients with IBD. Conclusion: Reduced expression of subunits of the UPS in IMACs of normal mucosa supports the concept of the presence of a nonreactive, anergic macrophage phenotype in the gut under normal conditions. Reinduction in IMACs of IBD mucosa reflects activated IMACs which can present antigenic peptides and thus support inflammation. Copyright © 2012 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Haem oxygenase-1 (HO-1) up-regulation was suggested to reduce mucosal tissue damage in inflammatory bowel disease (IBD) and an up-regulation of HO-1 expression in patients with Crohn's disease (CD) and ulcerative colitis (UC) was demonstrated. A HO-1 gene promoter microsatellite (GT)n dinucleotide repeat polymorphism was associated with regulation of HO-1 in response to inflammatory stimuli. We therefore hypothesized that IBD patients might segregate into phenotypes with high or low HO-1 inducibility. Ethylenediamine tetraacetic acid blood samples were obtained from 179 CD patients, 110 UC patients and 56 control patients without inflammation. Genomic DNA was purified and the 5′-flanking region of the HO-1 gene containing the (GT)n dinucleotide repeat was amplified. Polymerase chain reaction (PCR) products were purified and the length of the PCR fragments was analysed. The number of (GT)n repeats in the population studied ranged from 13 to 42. The distribution of the allele frequencies was comparable in patients and controls for both the short and the long alleles. The frequencies of short-, middle- and long-sized alleles were not changed among the groups studied. No correlation was found between IBD and microsatellite instability detected in five individals. Our data indicate that (GT)n dinucleotide repeats of the HO-1 promotor region have no significance for the pathophysiology and disease course of IBD. [ABSTRACT FROM AUTHOR]

Aims: The aim of the present study was to evaluate the 6-month survival rate of patients with inoperable or metastatic pancreatic cancer treated with irinotecan and gemcitabine plus 5-fluorouracil. Secondary efficacy end points included response rate, time to progression (TTP), overall survival (OS) and toxicity. Patients and Methods: 30 patients with histologically proven pancreatic carcinoma and at least one bidimensionally measurable lesion were enrolled. Of the patients, 83% had metastatic and 17% locally advanced disease. One cycle, lasting 21 days, comprised treatment on days 1 and 8 consisting of 75 mg/m2 irinotecan i.v. for 90 min, 1,000 mg/m2 gemcitabine i.v. for 30 min and 2,000 mg/m2 fluorouracil (5-FU) for 24 h. A total of six cycles was planned for each patient. Results: 28 patients competed at least one treatment cycle and were therefore assessable for efficacy, and 75% of them achieved the primary end point of the study (survival after 6 months). One-year survival was 25%. Stabilization (partial response and stable disease) was observed in 35.7% (10/28) and partial remission in 7.1% (2/28). The objective response rate was 7.1% (2/28) after completion of the six cycles. Median TTP was 3.4 months (1.2–11.5), and median OS was 8.3 months (2.1–36.2). Regarding severe hematological toxicities, only neutropenia was observed (grade 3 20.7%, 6/29, and grade 4 3.5%, 1/29). In spite of anti-emetic supportive care, nausea affected most of the patients: 79.3% (23/29). Grade 3 vomiting was observed in 4 of the 29 patients (13.8%) and grade 4 in 1 patient (3.5%). Only 1 patient experienced diarrhea grade 3 (3.5%) and 1 patient (3.5%) suffered from a grade 3 peroneal nerve enervation. Conclusions: A combination of irinotecan, gemcitabine and 5-FU is feasible and shows considerable efficacy in patients with inoperable or metastatic pancreatic cancer. Due to its low toxicity, this combination might be an interesting cytotoxic regimen in addition to targeted therapies. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Recently we demonstrated that in inflammatory bowel disease (IBD) macrophage-oxidative burst activity is increased and NADPH oxidase mRNA is induced. The herbal phenylethanoid acteoside isolated from Plantago lanceolata L. was shown to exhibit anti-oxidative potential. Using the dextran sulphate sodium (DSS)-induced colitis model, in this study we have assessed whether systemic application of acteoside affects colitis. Colitis was induced by DSS in Balb/c mice. Treatment with acteoside (120, 600 µg/mouse/day) was performed intraperitoneally. The colon lengths were determined. Colonic tissue was scored histologically (max. score 8) by a blinded investigator. T cells isolated from mesenteric lymph nodes (MLN) were stimulated with anti-CD3 antibody in the presence of interleukin (IL)-2 (final concentration 10 U/ml). After incubation for 24 h, IL-1β, IL-6, IL-12 tumour necrosis factor (TNF)-α and interferon (IFN)-γ levels in supernatants were analysed by the beadlyte® cytokine detection system. Histological scoring of colonic tissue revealed that application of acteoside was followed by a significantly improved histological score. In acute colitis the histological score was 3·2 with acteoside versus 5·2 with phosphate-buffered saline (PBS) ( P < 0·02). In chronic colitis both 120 µg (3·3 versus 5·2) or 600 µg acteoside (3·0 versus 5·2) significantly ameliorated colitis (both P < 0·02). Stimulated MLN from mice with chronic DSS-induced colitis treated with acteoside showed a significant down-regulation of IFN-γ secretion (195 pg/ml with 600 µg acteoside versus 612 pg/ml with PBS, P < 0·02). Inhibition of oxidative burst activity with acteoside reduced mucosal tissue damage in DSS colitis and could be a therapeutic alternative for IBD treatment. Further studies of this agent are warranted. [ABSTRACT FROM AUTHOR]

The cathepsins D (CTSD), B (CTSB) and L (CTSL) are important for the intracellular degradation of proteins. Increased cathepsin expression is associated with inflammatory diseases. We have shown previously an induction of CTSD expression in intestinal macrophages (IMAC) in inflamed mucosa of patients with inflammatory bowel disease (IBD). Here we investigated the regulation of CTSB and CTSL in IMAC during IBD and effects of CTSD and CTSB/CTSL inhibition in vivo. Human IMAC were isolated from normal and inflamed mucosa. Reverse transcription–polymerase chain reaction (RT–PCR) was performed for CTSB and CTSL mRNA. Immunostaining was used to confirm PCR results. Cathepsin inhibition was investigated in the dextran–sulphate–sodium (DSS) colitis model in mice with application of pepstatin A (CTSD inhibitor), CA-074 (CTSB inhibitor) and Z-Phe-Tyr-aldehyde (CTSL inhibitor). CTSL mRNA was significantly up-regulated in IMAC isolated from IBD mucosa. Up-regulated protein expression was found mainly in areas of mucosal damage by immunostaining. Inhibition of CTSD in mouse DSS colitis was followed by an amelioration of the disease. Inhibitor-treated mice showed a significant lower histological score (HS) and less colon reduction in comparison to controls. Similarly, simultaneous inhibition of CTSB/CTSL was followed by a significant amelioration of colitis. Expression of tissue-degrading cathepsins is increased in IMAC in IBD. Inhibition of CTSD as well as CTSB/CTSL is followed by an amelioration of experimental colitis. The prevention of mucosal damage by cathepsin inhibition could represent a new approach for the therapy of IBD. [ABSTRACT FROM AUTHOR]

Monocytes (MO) migrating into normal, non-inflamed intestinal mucosa undergo a specific differentiation resulting in a non-reactive, tolerogenic intestinal macrophage (IMAC). Recently we demonstrated the differentiation of MO into an intestinal-like macrophage (MAC) phenotype in vitro in a three-dimensional cell culture model (multi-cellular spheroid or MCS model). In the mucosa of patients with inflammatory bowel disease (IBD) in addition to normal IMAC, a reactive MAC population as well as increased levels of monocyte chemoattractant protein 1 (MCP-1) is found. The aim of this study was to investigate the influence of MCP-1 on the differentiation of MO into IMAC. MCS were generated from adenovirally transfected HT-29 cells overexpressing MCP-1, macrophage inflammatory protein 3 alpha (MIP-3α) or non-transfected controls and co-cultured with freshly elutriated blood MO. After 7 days of co-culture MCS were harvested, and expression of the surface antigens CD33 and CD14 as well as the intracellular MAC marker CD68 was determined by flow-cytometry or immunohistochemistry. MCP-1 and MIP-3α expression by HT-29 cells in the MCS was increased by transfection at the time of MCS formation. In contrast to MIP-3α, MCP-1 overexpression induced a massive migration of MO into the three-dimensional aggregates. Differentiation of IMAC was disturbed in MCP-1-transfected MCS compared to experiments with non-transfected control aggregates, or the MIP-3α-transfected MCS, as indicated by high CD14 expression of MO/IMAC cultured inside the MCP-1-transfected MCS, as shown by immunohistochemistry and FACS analysis. Neutralization of MCP-1 was followed by an almost complete absence of monocyte migration into the MCS. MCP-1 induced migration of MO into three-dimensional spheroids generated from HT-29 cells and inhibited intestinal-like differentiation of blood MO into IMAC. It may be speculated that MCP-1 could play a role in the disturbed IMAC differentiation in IBD mucosa. [ABSTRACT FROM AUTHOR]

Colonography based on magnetic resonance imaging (MRI) appears to be a promising technique for polyp assessment in the colon. Several studies have evaluated this method for colonic assessment in patients with inflammatory bowel disease. We briefly review different methodologies such as dark lumen and bright lumen techniques for abdominal MRI. In addition, recently published studies concerning the sensitivity and accuracy in detecting inflammatory bowel changes in inflammatory bowel disease using MRI are discussed. [ABSTRACT FROM AUTHOR]

Increased expression of CD44 variant isoforms have been shown on the inflammatory infiltrates in human and mouse colitis and blockade or deletion of CD44 isoforms inhibit experimental colitis. The objective of this study was to find out if short-term treatment of CD44 antibodies specific to CD44v7, but not to other variant isoforms, suppresses leucocyte–endothelial interaction in chronic dextran sodium sulphate (DSS)-induced colitis in mice. Chronic colitis was induced by oral administration of four cycles of 5% DSS in BALB/c mice. Expression of CD44 was investigated on isolated mononuclear cells of the gut immune system. In established colitis, mice were treated with antibodies against CD44v7 or CD44v4 three times in 7 days. Intravital microscopy was used to study leucocyte–endothelial interactions and leucocyte extravasation. As a marker of inflammatory infiltrates myeloperoxidase was quantified in gut tissue. CD44-induced apoptosis was determined by fluorescence staining of hypodiploidic cell nuclei. In chronic DSS-induced colitis both CD44 variant isoforms, v4 and v7 were significantly up-regulated on mononuclear cells. However, whereas anti-CD44v7 antibody treatment induced a marked restoration of the gut mucosa and significantly reduced endothelial sticking and extravasation of circulating leucocyte in vivo ( P < 0·01), application of anti-CD44v4 or an isotype control antibody had no anti-inflammatory effect. A significant reduction of myeloperoxidase activity was detected after blockade of CD44v7, but not v4. Short-term treatment with anti-CD44v7 antibody blocks T cell extravasation and recruitment to the intestinal mucosa and cures established experimental colitis. [ABSTRACT FROM AUTHOR]

Background and methods: Cytosin-guanosin dinucleotide (CpG) motifs of bacterial DNA are known to be potent activators of innate immunity. We have shown previously that administration of CpG containing oligodeoxynucleotide (CpG-ODN) to mice before the onset of dextran sodium sulphate induced colitis ameliorated colitis and inhibited induction of proinflammatory cytokines. To investigate the possible involvement of CD4+ T cells in the prophylactic CpG-ODN effects, we used the SCID transfer model of colitis. Results: CD4+D62L7+ T cells from CpG-ODN treated donors did not induce significant intestinal inflammation in SCID recipients, in contrast with control cells. Additionally, cotransfer of these cells with CD4+CD62L+ cells from normal mice protected recipient animals from colitis, indicating regulatory activity. Also, CD4+CD62L+ cells from toll-like receptor 9 deficient animals induced a significantly more severe colitis in SCID recipients than cells from wild-type littermate controls, suggesting a similar protective role of "endogenous" bacterial DNA leading to a less "aggressive" phenotype of these cells. There was no detectable difference in regulatory T cell surface markers between aggressive and attenuated cell pools but attenuated cell pools showed reduced proliferation in vitro and in vivo and produced less interferon y, interleukin (IL)-5, and IL-6 after anti-CD3 stimulation. Conclusions: Collectively, our data support the concept that both endogenous bacterial DNA and exogenously supplied CpG motifs of bacterial DNA induce regulatory properties in CD4+ T cells. Therefore, bacterial DNA derived from the normal gut flora may contribute essentially to the homeostasis between effector and regulatory immune mechanisms in healthy individuals to protect them from chronic intestinal inflammation. [ABSTRACT FROM AUTHOR]

Background: The glycoprotein (gp) 96 links the adaptive with the innate immune system. It is a chaperone with a binding domain for peptides generated by proteasomal degradation. During cellular stress, peptide loaded gp96 can be released and presented to T cells by antigen presenting cells (APCs). Methods: mRNAs from in vitro differentiated macrophages (iv mac) and normal intestinal macrophages (IMACs) were compared by subtractive hybridisation and Affymetrix GeneChip analysis. Differentiation induced expression of gp96 was investigated in the multicellular spheroid (MCS) model. In vivo gp96 protein expression was detected by double labelling immunohistochemistry of human colon and in the CD4+ CD62L+ T cell transfer mouse model. Results: Five of 76 clones obtained by subtractive hybridisation revealed >99% sequence homology to gp96. Affymetrix GeneChip analysis confirmed induction of gp96 in IMACs. Gp96 mRNA was detected in IMACs from normal and intestinal bowel disease mucosa. Induction of gp96 protein was observed after seven days in the MCS model of IMAC differentiation. Immunohistochemistry confirmed the presence of gp96 protein in IMACs in normal mucosa as well as in mucosa from patients with ulcerative colitis and diverticulitis. In mucosa from Crohn's disease (CD) patients, gp96 protein was not detectable. In the CD4+ CD62L+ T cell transfer mouse model, gp96 was verifiable in non-activated IMACs. Conclusion: Gp96 is induced during differentiation of normal IMACs but is not detected in IMACs in CD mucosa. As gp96 has been described as having a role in tolerance induction, this may be relevant for loss of tolerance against luminal bacteria found in CD patients. [ABSTRACT FROM AUTHOR]

Haem-oxygenase-1 (HO-1) has been shown to exert anti-inflammatory, anti-apoptotic and anti-proliferative effects. We investigated HO-1 expression in patients with inflammatory bowel disease (IBD) and could demonstrate a scattered expression of HO-1 in the intestinal epithelium of severely inflamed colonic mucosa of patients with IBD compared to control specimens such as diverticulitis, suggesting dysregulated expression in IBD. To further analyse potential mechanisms of HO-1 induction in the intestine we employed anin vitroepithelial cell apoptosis model and an experimental colitis model.In vitroinduction of HO-1 by the HO-1 inducer cobalt protoporphyrin (CoPP) resulted in a dose-dependent down-regulation of caspase-3 activation in HT-29 cells, indicating an anti-apoptotic function of HO-1 in the intestine.In vivo, preventive HO-1 induction by CoPP in acute dextran sodium sulphate (DSS)-induced colitis led to a significant down-regulation of colonic inflammation (P < 0·01) with a concomitant reduction in interferon (IFN)-γ − but unaffected interleukin (IL)-10-secretion by isolated mesenteric lymph nodes (P < 0·01). Additionally, TUNEL staining of colonic sections demonstrated fewer apoptotic epithelial cells in the colon of CoPP treated animals. No beneficial effects were observed if HO-1 was induced by CoPP after the onset of acute colitis or in chronic DSS-induced colitis. In conclusion, the data suggest a protective role of HO-1 if it is induced before the onset of inflammation. However, as shown by the lack of effects in established acute or in chronic colitis, the induction of HO-1 may not be a promising approach for the treatment of IBD. [ABSTRACT FROM AUTHOR]

Background: Clinical and experimental studies suggest that appendectomy can protect against development of ulcerative colitis and Crohn’s disease. However, how T cells in the appendix affect the development of colitis has not been clarified. Aim: To investigate the in vivo migration and activation of colitis-inducing CD62L+ cells during development of chronic colitis. Methods: CD62L+CD4+ cells were fluorescently labeled and transferred to severe combined immunodeficient (SCID) mice to induce colitis. In vivo migration of T cells into the mucosa of the appendix and colon was quantified by in vivo microscopy after 7 weeks. In a second experiment, unlabeled CD62L+CD4+ cells were transferred, reisolated after 7 weeks, and adhesion molecule (integrin α4β7) and costimulatory molecule (CD154) expression was analyzed. Results: Six to eight weeks after CD62L+CD4+ cell transfer, SCID mice developed chronic colitis. In vivo microscopic analysis demonstrated a preferential migration of fluorescence-labeled CD62L+CD4+ cells into the mucosa of the appendix versus the colon. Re-isolation of lamina propria cells from mice with colitis confirmed that CD62L+CD4+ cell migration was significantly enhanced in the appendix, compared to the colon (3.5-fold). Furthermore, a higher proportion of CD62L+CD4+ cells re-isolated from the appendix expressed integrin α4β7 and CD154 than from the colon. Conclusion: This study demonstrates the preferential migration of CD62L+CD4+ cells into the appendix as compared to the colon. This migration pattern correlated with upregulation of integrin α4β7 and CD154 (CD40 ligand) on T cells. Our results suggest an important role of the appendix in the pathogenesis of colitis. Copyright © 2005 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background : Fistulae are a common complication in up to 35% of all patients with Crohn's disease. Their therapy is difficult and frequently unsatisfactory. To date, no histological comparison of Crohn's disease fistulae with non-inflammatory bowel disease fistulae has been performed. In addition, Crohn's disease fistulae have not been well characterized morphologically. Methods: Eighty four fistulae from Crohn's disease patients were compared with 13 fistulae from controls. Haematoxylin-eosin staining, electron microscopy, and immunohistochemistry for panCytokeratin (epithelial cells), CD20 (B cells), CD45R0 (T cells), and CD68 (macrophages) were performed according to standard techniques. In addition, histopathological findings were compared with clinical and laboratory data. Results: In 31.0% of controls and 27.4% of Crohn's disease specimens, fistulae had a lining of flattened intestinal epithelium without goblet cells or, in the case of cutaneous/perianal disease, narrow squamous epithelium. Non-epithelialised fistulae were covered by a thin layer of (myo)fibroblasts, focally forming a new basement membrane, as demonstrated by electron microscopy. All fistulae were surrounded by granulation tissue. Crohn's disease fistulae presented with central infiltration by CD45R0+ T cells, followed by a small band of CD68+ macrophages and dense accumulation of CD20+ B cells. In contrast, in controls, there was dense infiltration by CD68+ macrophages with only few CD20+ B cells and CD45R0+ T lymphocytes. Conclusions: Fistulae in Crohn's disease differ markedly from non-Crohn's disease fistulae with regard to their cellular composition. The presence of an epithelial lining in a subgroup of fistulae may be important for the therapeutic approach and healing process. [ABSTRACT FROM AUTHOR]

Plasminogen activator inhibitor-1(PAI-1) levels were found to be associated with obesity, indicating that adipocytes might influence PAI-1 plasma levels. In addition, the 4G/5G promoter polymorphism of the PAI-1 gene possibly modulates PAI-1 gene transcription and, as a consequence, PAI-1 plasma levels. Metabolic parameters, diabetes complications, PAI-1 plasma levels, and PAI-1 promoter genotypes were determined and were tested for correlation in 547 Caucasian patients with type 2 diabetes. Genotyping was performed by using allele-specific PCR, and PAI-1 plasma levels were measured in 547 well-characterized subjects with type 2 diabetes. The allelic frequencies of the polymorphism(0.56 for the 4G-genotype, 0.44 for the 5G-genotype) were not different from those observed in nondiabetic controls. The PAI-1 concentration was positively associated with MI, but not with the 4G/5G polymorphism. Statistical analysis of metabolic parameters, diabetic complications, and the 4G/5G polymorphism revealed that serum fibrinogen levels were significantly higher in the 4G/4G subgroup compared with the 4G/5G and 5G/5G subgroups. The correlation between serum fibrinogen and 4G allele remained significant, even when additional variables, such as gender, age, BMI, duration of diabetes, and HbA1c, were controlled. In patients with type 2 diabetes mellitus, the PAI-1 4G/5G promoter polymorphism does not predict PAI-1 plasma levels and is not associated with common metabolic parameters besides fibrinogen levels. [ABSTRACT FROM AUTHOR]

Several effects of bile acids (BAs) on colonic epithelial cells (CECs) have been described, including induction of proliferation and apoptosis. Some of these effects are mediated through activation of the NF-κB transcriptional system. In this study, we investigated the molecular mechanisms underlying the BA-induced gene expression in CECs. The human CEC line HT-29 and primary human CECs were treated with dilutions of salts of deoxycholic acid (DCA) and taurodeoxycholic acid (TDCA). NF-κB binding activity was analyzed with EMSA, Re1A translocation with immunofluorescence, and IκBα and RelA-phosphorylation with Western blot analysis. IL-8 mRNA and protein expression were assessed by quantitative PCR and ELISA. Functional impact of NF-κB activation was determined by blocking the proteasome activity with MG132 or by preventing IKK activity with a dominant-negative IKKβ delivered by adenoviral dominant-negative (dn) IKKβ (Ad5dnIKKβ). DCA and TDCA induced IL-8 expression in a dose- and time-dependent manner. It is interesting that DCA but not TDCA induced IκBα-phophorylation, RelA translocation, and NF-κB binding activity. Accordingly, the proteasome inhibitor MG132 blocked DCA- but not TDCA-induced IL-8 gene expression. In contrast, TDCA-induced IL-8 gene expression correlated with enhanced RelA phosphorylation, which was blocked by Ad5dnIKKβ. Our data suggest that DCA-induced signal transduction mainly utilized the IκB degradation and RelA nuclear translocation pathway, whereas TDCA primarily induced IL-8 gene expression through RelA phosphorylation. These differences may have implications for the understanding of the pathophysiology of inflammation and carcinogenesis in the gut. [ABSTRACT FROM AUTHOR]

The collagenous repeat-containing sequence of 26-kDa protein (CORS-26) was recently described as a new gene that is induced during adipocyte differentiation. Since the transcription factors specificity protein-1 (SP-1) and PPARγ have been demonstrated to modulate transcriptional activation of adipocytic genes, we investigated the putative role of SP-1 and PPARγ in the regulation of the murine CORS-26 promoter. Computer-based sequence analysis revealed two putative SP-1 binding sites and binding sites for PPARγ and Pit-1 within the TATA-box containing promoter. Electrophoretic mobility shift assays (EMSA) with nuclear extracts from 3T3-L1 adipocytes and appropriate promoter fragments demonstrated that SP-1 binds specifically to both SP-1 binding sites. Specificity was demonstrated by (i) the appearance of supershift bands, (ii) competition experiments and, (iii) by using oligonucleotides carrying mutated SP-1 binding sites. Functional promoter activity was analyzed by Luciferase reporter gene assays and SP-1 was shown to exert inhibitory effects on the transcriptional activation of the murine CORS-26 gene. Additionally, specific binding activity of PPARγ and Pit-1 to the CORS-26 promoter was demonstrated. Taken together, the present data demonstrate the functionality of the proximal murine CORS-26 promoter, which is regulated specifically by two SP-1 binding sites via SP-3-independent repressive effects of SP-1 on transcriptional activation. Pit-1 and PPARγ can bind specifically to the promoter and might play an additive functional role in gene regulation of murine CORS-26. [Copyright &y& Elsevier]

Down-regulation of receptors involved in the recognition or transmission of inflammatory signals and a reduced responsiveness support the concept that macrophages are ‘desensitized’ during their differentiation in the intestinal mucosa. During inflammatory bowel disease (IBD) intestinal macrophages (IMACs) change to a reactive or ‘aggressive’ type. After having established a method of isolation and purification of IMACs, message for cathepsin D was one of the mRNAs we found to be up-regulated in a subtractive hybridization of Crohn's disease (CD) macrophages versus IMACs from control mucosa. The expression of cathepsin D in intestinal mucosa was analysed by immunohistochemistry in biopsies from IBD and control patients and in a mouse model of dextran sulphate sodium (DSS)-induced acute and chronic colitis. IMACs were isolated and purified from normal and inflamed mucosa by immunomagnetic beads armed with a CD33 antibody. RT-PCR was performed for cathepsin D mRNA. Results were confirmed by Northern blot and flow cytometrical analysis. Immunohistochemistry revealed a significant increase in the cathepsin D protein expression in inflamed intestinal mucosa from IBD patients compared to non-inflamed mucosa. No cathepsin D polymerase chain reaction (PCR) product could be obtained with mRNA from CD33-positive IMACs from normal mucosa. Reverse transcription (RT)-PCR showed an induction of mRNA for cathepsin D in purified IMACs from IBD patients. Northern blot and flow cytometry analysis confirmed these results. Cathepsin D protein was also found in intestinal mucosa in acute and chronic DSS-colitis but was absent in normal mucosa. This study shows that expression of cathepsin D is induced in inflammation-associated IMACs. The presence of cathepsin D might contribute to the mucosal damage in IBD. [ABSTRACT FROM AUTHOR]

The murine gene for CORS-26 is located on mouse chromosome 15A2 and its expression has been reported to be restricted to fibroblasts, cartilage and kidney. Here, the complete genomic organization of the corresponding human CORS-26 gene with exon/intron boundaries and exon-specific primer combinations is presented. Additionally, a 1.2 kb fragment of the TATA box-containing promoter region was cloned and analyzed for putative transcription factor binding sites. The deduced amino acid sequence is presented completely. Northern blot analysis using a human multiple-tissue cDNA panel demonstrated expression of human CORS-26 mRNA in colon and small intestine. Additionally, RT-PCR analysis revealed expression of CORS-26 mRNA in placenta, fibroblasts and white adipose tissue. The chromosomal localization of the human CORS-26 gene was mapped to human chromosome 5p by fluorescence in situ hybridization (FISH). In humans, chromosomal imbalances on chromosome 5p were reported to be involved in the pathogenesis of osteosarcoma. Therefore, a human bone tumor cDNA panel was investigated and a strong CORS-26 mRNA expression was found in osteosarcoma, chondroblastoma and giant cell tumor. The present data provide the basis for further investigation of CORS-26 gene regulation in the context of mesenchymal tissue development and in the pathogenesis of bone or skeletal disease. [Copyright &y& Elsevier]

Intestinal inflammation in inflammatory bowel disease (IBD) and experimental models of colitis is characterized by a dysregulated intestinal immune response with elevated levels of Th1 cytokines. The luminal flora has been implicated as a major factor contributing to the initiation and perpetuation of inflammation in experimental colitis by mechanisms not known. Bacterial DNA contains unmethylated cytosin–guanosin dinucleotides (CpG) which strongly activate Th1-mediated immune responses. To test whether these CpG-motifs modulate intestinal inflammation we treated mice with dextran sulphate sodium (DSS)-induced colitis with CpG-containing oligodeoxynucleotides (CpG-ODN). CpG-ODN given after the onset of DSS colitis aggravated the disease, as indicated by a significantly increased loss of body weight and a 30% increase of the histological score. Further, we found a severe increase of proinflammatory cytokines (interleukin (IL)-6: 40-fold; interferon (IFN)- γ : 11-fold). In a pretreatment setting CpG-ODN reduced weight loss significantly and reduced intestinal inflammation by 45%. Colonic IFN- γ and IL-6 mRNA levels were reduced by 75%, and IL-10 was elevated by 400% compared to controls. The prophylactic CpG-effect was not imitated by IL-12 because IL-12 pretreatment was not protective. In time-course experiments, CpG-ODN pretreatment over 5 days resulted in a tolerance effect concerning its IFN- γ-inducing quality, and during the following days of colitis induction IL-10 secretion from mesenterial lymph node cells was elevated compared to controls. Therefore, the prophylactic effect of CpG-ODN might be explained by its tolerizing effect and/or the increased ability for IL-10 production during the consecutive intestinal inflammation. [ABSTRACT FROM AUTHOR]

The murine gene for CORS-26 shows striking homologies to the adipocyte-specific secretory protein adiponectin (belonging to the newly discovered C1q/TNF molecular superfamily) and its expression has been reported to be restricted to fibroblasts, cartilage and kidney. However, the present data demonstrate specific induction of CORS-26 mRNA expression in hormonally differentiated 3T3-L1 adipocytes, but not in preadipocytes. Furthermore, CORS-26 mRNA expression could be demonstrated in human synovial adipocytes of the knee by in situ hybridization. Since the genes for CORS-26 and adiponectin are homologous for their COOH-terminal globular domain and of their N-terminal collagenous domain, they might have originated by divergence from an innate mesenchymal precursor molecule directing the development of myocytes, adipocytes and chondrocytes from a mesenchymal stem cell. Here, the complete genomic organization with exon/intron boundaries together with exon-specific primer combinations are presented. Additionally, ∼1 kb of the TATA-box-containing promoter region was cloned and analyzed for putative transcription factor binding sites. The chromosomal localization of the murine CORS-26 gene was mapped to mouse chromosome 15 A2 by fluorescence in situ hybridization (FISH). Since the linkage loci for proteoglycan-induced arthritis and MRL/lpr arthritis in mice have been mapped to that chromosomal region, CORS-26 might represent the underlying mechanism of disease. The present data provide the basis for further investigation of the CORS-26 gene regulation in the context of mesenchymal tissue development, chondrocyte/adipocyte function and bone or skeletal disease. [Copyright &y& Elsevier]

Infliximab (anti-TNF-α monoclonal antibody)induces remission in 30-40% of Crohn's disease patients. Treatment response is a stable trait. Two cohorts from independent, prospective clinical trials of infliximab in Crohn's disease were studied. Hypotheses were generated in an exploratory cohort (n = 90) and then tested in a confirmatory cohort (n = 444), using a statistical design, which is stable against type 1 and type 2 errors. In the exploratory cohort, the mutant 196Arg allele of TNFR-II (exon 6 polymorphism) and a novel silent polymorphism in exon 2 of TNFR-II were associated with lack of response to infliximab (83.3% in homozygote mutant 196 Arg patients vs 36.9% in heterozygotes and wild4type homozygotes (P = 0.036) and 85.7% in homozygote mutant exon 2 patients vs 36.1% (P = 0.01), respectively). None of the homozygote mutant individuals (0/6) achieved clinical remission, whereas the remission rate was 35.7% (30/84) in wild4type homozygotes and heterozygotes. In the large second cohort, the observed genotype-phenotype associations were not replicated. Other polymorphisms (TNF-α promoter -238, -308, -376, -857, -1031, TNF-R-I -609, +36 (exon 1), TNF-R-II 1663, 1690 (3'-UTR)) were not associated with treatment response in both cohorts (P > 0.5). None of the polymorphisms was associated with refractory Crohn's disease itself when compared to healthy controls. In a two-cohort study, a series of polymorphisms in the TNF, the TNF-R-I and in the TNF-R-II genes could be thoroughly excluded as pharmacogenetic markers for a treatment response to infliximab and as etiologic factors for Crohn's disease, respectively. The discrepancy between the two cohorts observed for the TNF-R-II exon 6 and exon 2 polymorphism may point to a weak effect on... [ABSTRACT FROM AUTHOR]

Macrophages play a central role during the pathogenesis of inflammation. In normal intestinal mucosa surface expression of typical macrophage markers such as CD14, CD16, CD11b or T-cell co-stimulatory molecules such as CD80 or CD86 is low indicating anergy and low pro-inflammatory activity of these cells. During inflammatory bowel disease (IBD) the mucosa is invaded by a population of macrophages displaying these markers, secreting higher cytokine levels and representing an activated cell population. CD33+ cells (macrophages) were isolated from normal and Crohn's disease mucosa and mRNA was isolated by polyT magnetic beads. A subtractive screening was performed subtracting mRNA from normal macrophages from those of Crohn's disease macrophages. Oxidative burst activity was determined by flow cytometry. Seventy clones were obtained by the subtractive mRNA screening. Sequencing showed > 99% homology to mRNA of monocyte chemoattractant protein-1 (MCP-1) for three clones. Five clones obtained by subtraction revealed > 99% homology to mRNA of cytochrome b (subunit gp91). Differential expression of the cytochrome b subunit gp91 and the cytosolic NADPH oxidase subunit p67 was confirmed by RT-PCR and ‘virtual’ Northern blots. The fluorescence ratio of stimulated versus unstimulated cells was 0·9 ± 0·16 in control macrophages indicating a lack of oxidative burst activity. In Crohn's disease this ratio was significantly increased to 1·80 ± 0·8 (P = 0·004) confirming the molecular data. In conclusion NADPH oxidase mRNA is down-regulated or absent in macrophages from normal mucosa correlating with a lack of oxidative burst activity. In IBD macrophage-oxidative burst activity is increased and NADPH oxidase mRNA induced. Inhibition of NADPH oxidase could be a new therapeutical target in IBD and reduce mucosal tissue damage in active IBD. [ABSTRACT FROM AUTHOR]

BACKGROUND: CD40 has been shown to be a functional activation antigen on a variety of cell types involved in immune responses. As intestinal fibroblasts and myofibroblasts may play a role during mucosal inflammation, we investigated the functional consequences of CD40 induction in primary cultures of human colonic fibroblasts. METHODS: Primary colonic lamina propria fibroblasts (PCLF) were isolated from endoscopic biopsies and surgical specimens. Cultures were used between passages 3 and 9. CD40 surface display was determined by FACS analysis and mRNA expression by reverse transcription-polymerase chain reaction. Secretion of cytokines was determined by ELISA. Nuclear factor kappaB (NFkappaB) activation was shown by electrophoretic mobility shift assay (EMSA). RESULTS: After priming with interferon gamma (IFN-gamma) (200 U/ml) for 72 hours, five of eight tested PCLF cultures showed induction of CD40 surface display (up to 10-fold). Induction of CD40 mRNA expression was demonstrated by semiquantitative polymerase chain reaction. In the responder-PCLF cultures, IFN-gamma alone caused a 1.5-5-fold increase in interleukin (IL)-8 secretion. Addition of 1 ng/ml CD40L was sufficient to achieve a further increase in IL-8, IL-6, or monocyte chemotactic protein 1 (MCP-1) secretion (2.5-18-fold of controls). Incubation with CD40L alone without priming with IFN-gamma had no effect. The proteasome inhibitor N-acetyl-leucinyl-leucinyl-norleucinal (ALLN 100 micro M) reduced IFN-gamma/CD40L mediated cytokine induction, suggesting participation of NFkappaB, which was directly demonstrated by EMSA. CD4+ T cells induced MCP-1 secretion by PCLF, which was prevented by addition of an excess of CD40-IgG fusion protein. CD40 expression on PCLF could also be demonstrated in vivo by immunohistochemistry. CONCLUSION: The CD40-CD40L pathway augments mucosal inflammatory responses via mucosal PCLF. CD40-CD40L mediated T cell/PCLF interactions could play an important role during intestinal mucosal inflammation. [ABSTRACT FROM AUTHOR]