Clinical predictors for a complicated course of disease in an inception cohort of patients with ulcerative colitis: results from the prospective, observational EPICOL study.

PURPOSE: The clinical course of ulcerative colitis (UC) is highly heterogeneous, with 20 to 30% of patients experiencing chronic disease activity requiring immunosuppressive or biologic therapies. The aim of this study was to identify predictors for a complicated disease course in an inception cohort of patients with UC. METHODS: EPICOL was a prospective, observational, inception cohort (UC diagnosis, ≤ 6 months) study in 311 patients with UC who were naive to immunosuppressants (IS)/biologics. A complicated course of disease was defined as the need for IS and/or biologic treatment (here therapy with a TNF-α antagonist) and/or UC-related hospitalisation. Patients were followed up for 24 months. RESULTS: Of the 307 out of 311 participants (4 patients did not meet the inclusion criteria "confirmed diagnosis of active UC within the last 6 months" (n = 2) and "immunosuppressive-naïve" (n = 2), analysis population), 209 (68.1%) versus 98 (31.9%) had an uncomplicated versus a complicated disease course, respectively. In a multivariate regression analysis, prior use of corticosteroids and prior anaemia were associated with a significantly increased risk for a complicated disease course (2.3- and 1.9-fold increase, respectively; p < 0.001 and p = 0.002). Based on these parameters, a risk model for patient stratification was developed. CONCLUSION: Our study identifies anaemia and an early need for corticosteroids as predictors for a complicated course of disease in an inception cohort of patients with UC. By determining these parameters in routine clinical practice, our results may support the identification of patients who might benefit from early escalation of therapy.

Self-assessment of treatment targets in patients with inflammatory bowel disease using a survey.

BACKGROUND: Physicians can improve their relationships with patients by understanding and meeting patients' treatment targets, leading to higher adherence to therapy and improved disease prognosis. In the current study, we performed a questionnaire-based survey to further understand treatment targets in patients with inflammatory bowel disease (IBD). METHODS: We created a questionnaire based on a point-allocation scale with 10 treatment target items. A total of 234 patients with IBD [Crohn's disease (n = 129) and ulcerative colitis (n = 105)] participated in three German IBD centers. Patients were asked to allocate a total of 10 points across the 10 items, with more points indicating more importance. RESULTS: The most important treatment targets for patients regarding their therapy were quality of life (2.78 points), control of defecation (1.53 points), and avoidance of IBD-related surgery (1.69 points). Avoiding surgery for IBD was less important in patients who had already undergone a surgical procedure than in those who had not (1.26 points versus 1.89 points, p < 0.001). Typical treatment targets, including mucosal healing (0.52 points) and normal biochemical markers (0.39 points), were not scored high by patients. The least important item was the possibility of all-oral therapy (0.19 points in 33 patients, 0 points in 201 patients). CONCLUSION: Treatment targets for patients were primarily related to quality of life, such as therapy side effects. Knowing these targets may improve patient-physician relationships and communication, and consequently, adherence to therapy.

Predictive parameters for the clinical course of Crohn's disease: development of a simple and reliable risk model.

PURPOSE: The aim of our study was to identify clinical parameters in recently diagnosed Crohn's disease (CD) patients for prediction of their disease course. METHODS: EPIC (Early Predictive parameters of Immunosuppressive therapy in Crohn's disease) is a prospective, observational study in 341 patients with a recent CD diagnosis (≤ 6 months), and naïve to immunosuppressants (IS) and anti-tumor necrosis factor α (TNF) agents. Patient characteristics were documented up to 2 years. In line with national and international guidelines, a complicated disease course was defined as need for immunosuppressants and/or anti-TNF agents, and CD-related hospitalization with or without immunosuppressants and/or anti-TNF agents. RESULTS: A total of 212 CD patients were analyzed of whom 57 (27%) had an uncomplicated disease within 24 months, while 155 (73%) had a complicated disease course: need for IS and/or anti-TNF agents (N = 115), CD-related hospitalization with or without IS/anti-TNF agents (N = 40). Identified risk predictors for a complicated disease were as follows: age at onset < 40 years (OR 2.3; 95% CI 1.2-4.5), anemia (OR 2.1; 95% CI 1.1-4.2), and treatment with systemic corticosteroids at first flare (OR 2.2; 95% CI 1.1-4.7). These three parameters were used to develop a risk model allowing prediction of the future disease course. CONCLUSION: Our three-parameter model enables an assessment of each CD patient's risk to develop a complicated disease course. Due to the easy accessibility of these parameters, this model can be utilized in daily clinical care to assist selecting the initial treatment for each individual patient.

Syndecan-4 Modulates Epithelial Gut Barrier Function and Epithelial Regeneration in Experimental Colitis.

Background: The transmembrane heparan sulfate proteoglycan Syndecan-4 (Sdc4) plays an important role in the regulation of various inflammatory disorders. However, the involvement of Sdc4 in intestinal inflammation remains unknown. Therefore, we assessed the impact of Sdc4 deficiency on experimental colitis and epithelial wound healing in vitro and in vivo. Methods: Dextran sulfate sodium (DSS)-induced colitis was monitored in wild type and Sdc4-deficient (Sdc4-/-) mice by assessment of body weight, histology, inflammatory cellular infiltration, and colon length. Syndecan-4 expression was measured by immunohistochemistry, Western blot, and quantitative real-time PCR. Epithelial permeability was evaluated by Evans blue measurements, Western blot, and immunohistological analysis of tight junction protein expression. Impact of Sdc4 on epithelial wound healing was determined by scratch assay in vitro and by colonoscopy following mechanical wounding in vivo. Results: In Sdc4-/- mice, colitis-like symptoms including severe weight loss, shortened colon length, histological damage, and invasion of macrophages and granulocytes were markedly aggravated compared with wild type (WT) animals. Moreover, colonic epithelial permeability in Sdc4-/- mice was enhanced, while tight junction protein expression decreased. Furthermore, Sdc4-/- colonic epithelial cells had lower cell proliferation and migration rates which presented in vivo as a prolonged intestinal wound healing phenotype. Strikingly, in WT animals, Sdc4 expression was reduced during colitis and was elevated during recovery. Conclusions: The loss of Sdc4 aggravates the course of experimental colitis, potentially through impaired epithelial cell integrity and regeneration. In view of the development of current treatment approaches involving Sdc4 inhibition for inflammatory disorders like arthritis, particular caution should be taken in case of adverse gastrointestinal side-effects.

Detection and characterization of murine colitis and carcinogenesis by molecularly targeted contrast-enhanced ultrasound.

AIM: To study mucosal addressin cellular adhesion molecule-1 (MAdCAM-1) and vascular endothelial growth factor (VEGF)-targeted contrast enhanced ultrasound (CEUS) for the assessment of murine colitis and carcinogenesis. METHODS: C57BL/6 mice were challenged with 3% dextran sodium-sulfate (DSS) for three, six or nine days to study the development of acute colitis. Ultrasound was performed with and without the addition of unspecific contrast agents. MAdCAM-1-targeted contrast agent was used to detect and quantify MAdCAM-1 expression. Inflammatory driven colorectal azoxymethane (AOM)/DSS-induced carcinogenesis was examined on day 42 and 84 using VEGF-targeted contrast agent. Highly specific tissue echogenicity was quantified using specialized software. Sonographic findings were correlated to tissue staining, western blot analysis and immunohistochemistry to quantify the degree of inflammation and stage of carcinogenesis. RESULTS: Native ultrasound detected increased general bowel wall thickening that correlated with more progressed and more severe DSS-colitis (healthy mice: 0.3 mm ± 0.03 vs six days DSS: 0.5 mm ± 0.2 vs nine days DSS: 0.6 mm ± 0.2, P < 0.05). Moreover, these sonographic findings correlated well with clinical parameters such as weight loss (r2 = 0.74) and histological damage (r2 = 0.86) (P < 0.01). In acute DSS-induced murine colitis, CEUS targeted against MAdCAM-1 detected and differentiated stages of mild, moderate and severe colitis via calculation of mean pixel contrast intensity in decibel (9.6 dB ± 1.6 vs 12.9 dB ± 1.4 vs 18 dB ± 3.33, P < 0.05). Employing the AOM/DSS-induced carcinogenesis model, tumor development was monitored by CEUS targeted against VEGF and detected a significantly increased echogenicity in tumors as compared to adjacent healthy mucosa (healthy mucosa, 1.6 dB ± 1.4 vs 42 d, 18.2 dB ± 3.3 vs 84 d, 18.6 dB ± 4.9, P < 0.01). Tissue echogenicity strongly correlated with histological analysis and immunohistochemistry findings (VEGF-positive cells in 10 high power fields of healthy mucosa: 1 ± 1.2 vs 42 d after DSS start: 2.4 ± 1.6 vs 84 d after DSS start: 3.5 ± 1.3, P < 0.01). CONCLUSION: Molecularly targeted CEUS is a highly specific and non-invasive imaging modality, which characterizes murine intestinal inflammation and carcinogenesis in vivo.

The 5A apolipoprotein A-I (apoA-I) mimetic peptide ameliorates experimental colitis by regulating monocyte infiltration.

BACKGROUND AND PURPOSE: New therapies for inflammatory bowel disease (IBD) are highly desirable. As apolipoprotein (apo)A-I mimetic peptides are beneficial in several animal models of inflammation, we hypothesized that they might be effective at inhibiting murine colitis. EXPERIMENTAL APPROACH: Daily injections of 5A peptide, a synthetic bihelical apoA-I mimetic dissolved in PBS, or PBS alone were administered to C57BL/6 mice fed 3% (w v(-1) ) dextran sodium sulfate (DSS) in drinking water or healthy controls. KEY RESULTS: Daily treatment with 5A peptide potently restricted DSS-induced inflammation, as indicated by improved disease activity indices and colon histology, as well as decreased intestinal tissue myeloperoxidase levels and plasma TNFα and IL-6 concentrations. Additionally, plasma levels of monocyte chemoattractant protein-1 and the monocyte expression of adhesion-mediating molecule CD11b were down-regulated, pro-inflammatory CD11b(+) /Ly6c(high) monocytes were decreased, and the number of intestinal monocytes was reduced in 5A peptide-treated animals as determined by intravital macrophage-related peptide-8/14-directed fluorescence-mediated tomography and post-mortem immunhistochemical F4/80 staining. Intravital fluorescence microscopy of colonic microvasculature demonstrated inhibitory effects of 5A peptide on leukocyte adhesion accompanied by reduced plasma levels of the soluble adhesion molecule sICAM-1. In vitro 5A peptide reduced monocyte adhesion and transmigration in TNFα-stimulated monolayers of human intestinal microvascular endothelial cells. Increased susceptibility to DSS-induced inflammation was noted in apoA-I(-/-) mice. CONCLUSIONS AND IMPLICATIONS: The 5A peptide is effective at ameliorating murine colitis by preventing intestinal monocyte infiltration and activation. These findings point to apoA-I mimetics as a potential treatment approach for IBD.

Translational 18F-FDG PET/CT imaging to monitor lesion activity in intestinal inflammation.

UNLABELLED: In patients with inflammatory bowel disease (IBD) and in murine IBD models, mucosal disease activity is routinely assessed by endoscopy and histologic evaluation. This information is valuable for monitoring treatment response, with mucosal healing being a major treatment goal. The aim of this study was to evaluate the translational potential of noninvasive (18)F-FDG PET/CT for the assessment of mucosal damage in murine dextran sodium sulfate (DSS) colitis and human IBD. METHODS: After induction of DSS colitis, (18)F-FDG uptake was serially assessed from colonic volumes of interest defined on PET/CT scans and intraindividually correlated to histologic findings and to infiltrating cell types. In addition, (18)F-FDG PET/CT scans of 25 Crohn disease patients were analyzed, and colonic (18)F-FDG uptake was correlated to endoscopically assessed damage. RESULTS: At days 4 and 7 after DSS induction, colonic (18)F-FDG uptake was significantly increased, with a distinct peak in the medial colon. (18)F-FDG uptake strongly correlated with histologic epithelial damage. Additionally, (18)F-FDG uptake increased in the bone marrow in the course of the disease, correlating with an increase in intestinal (18)F-FDG uptake. Histology and fluorescence-activated cell sorting analysis of the bone marrow of DSS mice revealed an increased number of immature neutrophils, whereas mucosal polymerase chain reaction suggested a correlation of (18)F-FDG uptake to T cell infiltration. In accordance with the results of (18)F-FDG PET/CT in DSS colitis, an increased (18)F-FDG uptake was found in 87% of deep mucosal ulcerations in IBD patients, whereas mild endoscopic lesions were detected only by (18)F-FDG PET/CT in about 50% of patients assessed. CONCLUSION: (18)F-FDG PET/CT is a noninvasive method for evaluation of both experimental colitis and Crohn disease patients and thereby offers promising translational potential.

Improving relapse prediction in inflammatory bowel disease by neutrophil-derived S100A12.

BACKGROUND: Prediction of inflammatory bowel disease relapse has important implications for therapeutic strategies. Fecal S100A12 has been reported as a novel marker of intestinal inflammation. The objective was to investigate the utility of S100A12 as a marker for the confirmation of stable remission and prediction of relapses. METHODS: We consecutively included 147 adults and 34 children with Crohn's disease (n = 61) or ulcerative colitis (n = 120). Over a 3-year period, we collected 686 stool samples and 861 serum samples during regular follow-up visits. S100A12 and calprotectin levels were measured by an enzyme-linked immunoassay. RESULTS: Fecal S100A12 correlated with S100A12 serum levels, other laboratory markers, as well as disease activity, location, and behavior. Fecal S100A12 levels in the relapse group differed significantly from those of the nonrelapse group. A baseline fecal S100A12 level of >0.5 mg/kg was significantly associated with disease relapse within 18 months. Time course analysis of fecal S100A12 before and after relapse showed a clear increase of S100A12 concentrations up to 6 months before clinical relapse. At 0.43 mg/kg, the sensitivity and specificity of S100A12 for predicting relapse already 8 to 12 weeks earlier were 70% and 83%, respectively. CONCLUSIONS: Regular measurements of fecal S100A12 levels reliably detect inflammatory bowel disease relapse at an early stage, which makes the test a promising noninvasive tool for monitoring and optimizing therapy, and may reduce the need for invasive investigations during disease follow-up.

Green tea polyphenol epigallocatechin-3-gallate shows therapeutic antioxidative effects in a murine model of colitis.

BACKGROUND AND AIMS: Leukocyte infiltration, up-regulation of proinflammatory cytokines and severe oxidative stress caused by increased amounts of reactive oxygen species are characteristics of inflammatory bowel disease. The catechin (2R,3R)-2-(3,4,5-Trihydroxyphenyl)-3,4-dihydro-1(2H)-benzopyran-3,5,7-triol-3-(3,4,5-trihydroxybenzoate), named epigallocatechin-3-gallate, EGCG, has been demonstrated to exert anti-inflammatory and antioxidative properties, reducing reactive oxygen species in the inflamed tissues. The aim of this study was to evaluate the therapeutic effects of EGCG in a murine model of colitis induced by oral administration of dextran sodium sulfate. METHODS: Mice received a daily oral administration of 6.9 mg/kg body weight EGCG or Piper nigrum (L.) alkaloid (2E,4E)-5-(1,3-benzodioxol-5-yl)-1-piperidin-1-ylpenta-2,4-dien-1-one, named piperine (2.9 mg/kg body weight) or the combination of the both - piperine was used in this combination to enhance the bioavailability of EGCG. RESULTS: In vivo data revealed the combination of EGCG and piperine to significantly reduce the loss of body weight, improve the clinical course and increase overall survival in comparison to untreated groups. The attenuated colitis was associated with less histological damages to the colon and reduction of tissue concentrations of malondialdehyde, the final product of lipid peroxidation. Neutrophils accumulation indicator myeloperoxidase was found to be reduced in colon tissue, while antioxidant enzymes like superoxide dismutase and glutathione peroxidase showed an increased activity. In vitro, the treatment with EGCG plus piperine enhanced the expression of SOD as well as GPO and also reduced the production of proinflammatory cytokines. CONCLUSION: These data support the concept of anti-inflammatory properties of EGCG being generally beneficial in the DSS-model of colitis, an effect that may be mediated by its strong antioxidative potential.

Cytomegalovirus (CMV)-Specific Perforin and Granzyme B ELISPOT Assays Detect Reactivation of CMV Infection in Inflammatory Bowel Disease.

The role of cytomegalovirus (CMV) infection in the pathogenesis and exacerbation of Inflammatory Bowel Disease (IBD) has been unresolved. Typically, the CMV genome remains dormant in infected cells, but a breakdown of immune surveillance can lead to re-activation of viral replication in the gut mucosa, which is not necessarily associated with viremia or changes in antibody titers. We hypothesized that the detection of CMV-specific CD8 effector T cells should permit the distinction between dormant and active CMV infection. As CD8 effector T cells, unlike memory CD8 T cells, have perforin (PFN) and granzyme B (GzB) preformed in their cytoplasmic granules, we employed single cell resolution ELISPOT assays to measure the CMV antigen-triggered release of these molecules by CD8 T cells isolated from subjects with IBD, and age-matched healthy controls. The frequencies of CMV-specific (GzB) and PFN-producing CD8 T cells were increased in IBD patients compared to healthy controls. Furthermore, the increased CMV reactivity was associated with active IBD disease and with longer disease duration. Notably, PCR on serum frequently failed to detect CMV DNA during flares. The data show that during active IBD there is a flare of CD8 T cell activity against CMV in a substantial proportion of IBD patients, suggesting CMV reactivation that serum PCR does not detect. While it remains open whether CMV reactivation is a cause or consequence of IBD, our data suggest that monitoring CMV antigen-specific effector CD8 T cells with GzB and PFN ELISPOT analysis can provide novel insights into the role of CMV infection in IBD. Additionally, our data have implications for the fields of transplantation, HIV, cancer, and autoimmune diseases, in all of which patient care critically depends on sensitive and reliable detection of a reactivation of CMV infection.

Collagen matrix-bound clotting factors (CMBCF) promote healing-associated events independent of factor XIII in an in vitro model.

We have previously explored in vitro as well as in vivo models of the biological effects of liquid fibrin glue (FG) containing factor XIII. The fixed combination of a collagen matrix and coagulation factors I and IIa (TachoSil(®) , Nycomed, Linz, Austria) is void of factor XIII. We aimed to determine whether (1) this preparation exerts similar effects to liquid FG on cells in an in vitro system, or (2) this effect is modulated by factor XIII. In an in vitro model, the effect of the fixed combination of collagen matrix and coagulation factors I and IIa (collagen matrix-bound clotting factor [CMBCF]) on the expression and secretion of growth factors (vascular endothelial growth factor, platelet-derived growth factor, fibroblast growth factor-2) by gastric epithelial (AGS) and mesenchymal cells (fibroblasts), as well as their proliferative response (WST-test), was compared in the presence and absence of factor XIII. The use of CMBCF compared with collagen type I matrix resulted in an increased proliferation rate of fibroblasts; there was an increased secretion of fibroblast growth factor-2. Gastric epithelial cells secreted more vascular endothelial growth factor and platelet-derived growth factor into the culture supernatant in the presence of CMBCF. All responses remained unaltered by the addition of factor XIII in different concentrations. In conclusion, CMBCF exerted effects similar to liquid FG in an in vitro model of healing. The addition of factor XIII did not alter the response of mesenchymal or epithelial cells, with respect to proliferation and growth factor secretion.

The tripeptide KdPT protects from intestinal inflammation and maintains intestinal barrier function.

Treatment options for inflammatory bowel disease (IBD) are incompletely helpful, and surgery is often needed. One promising class of future therapeutic agents for IBD is melanocortin-related peptides, which exhibit potent immunomodulatory effects. We investigated KdPT, a tripeptide derivative of the C-terminus of α-melanocyte-stimulating hormone, as an anti-inflammatory small molecule in vivo and in vitro. Intestinal inflammation was studied after oral administration of dextran sodium sulfate and in IL-10 gene-deficient mice. The effects of KdPT on key colonic epithelial cell functions were studied in vitro and in vivo by evaluating proliferation, wound healing, transepithelial resistance, and expression of tight junction proteins. Melanin assays were performed to determine the melanotropic effects of KdPT. KdPT-treated animals showed markedly reduced severity of inflammation in both colitis models. In colonic epithelial cells, KdPT increased proliferation, accelerated closure of wounds, and improved transepithelial electrical resistance after stimulation with interferon-γ/tumor necrosis factor-α. Moreover, treatment with KdPT also prevented the loss of tight junction protein expression and improved barrier function in vivo. KdPT acted independently of IL-1 receptor type I in vivo and did not affect melanogenesis in vitro. KdPT is capable of attenuating the course of experimental colitis in different models and maintains epithelial cell function. Furthermore, KdPT does not induce pigmentation, emphasizing the potential of this small molecule for the future treatment of IBD.

Course of a HBsAg positive liver transplantation in a hepatitis B and D virus coinfected recipient.

The increasing demand for transplantation has led to consideration of liver grafts from donors exposed to hepatitis B virus (HBV). Six transplantations of liver grafts from hepatitis B surface antigen (HBsAg) positive donors have been reported; two recipients suffered from HBV/HDV (hepatitis Delta virus) coinfection and were followed up for 10-12 months. Here, we report a 56 months follow-up of a HBV/HDV-coinfected recipient of a HBsAg positive liver graft. Posttransplant combination prophylaxis consisted of hepatitis immunoglobulin, lamivudine and adefovir dipivoxil. HBsAg remained positive during stable posttransplant follow-up and subclinical HDV reinfection with low replication rate was detected at 1 month. Pegylated interferon therapy was introduced after documentation of histological evidence of mild chronic hepatitis, but without virological response after 48 weeks. Finally, antiviral treatment was switched to tenofovir disoproxil fumarate. More than 50 months posttransplant the recipient revealed clinical symptoms of decompensated liver cirrhosis and has been relisted for liver transplantation. In conclusion HBsAg positive liver grafts in HBsAg positive recipients with HDV coinfection may result in virological recurrence and rapid development of liver cirrhosis.

The functional -374T/A polymorphism of the receptor for advanced glycation end products may modulate Crohn's disease.

The receptor for advanced glycation end products (RAGE) is involved in innate immune mechanisms. Polymorphisms of the RAGE gene have been described as a factor amplifying inflammation in susceptible patients, but the association with Crohn's disease (CD) is not known. The coding RAGE polymorphism G82S (rs2070600) and two promoter polymorphisms, -374T/A (rs1800624) and -429T/C (rs1800625), were studied in two samples from Germany and the United States consisting of 421 and 317 CD patients and 549 and 218 controls, respectively. To test the functional relevance, additional data on serum soluble RAGE (sRAGE), tissue RNA, and protein levels were collected and immunohistochemical stainings of bowel tissue of CD patients and healthy controls as well as models of experimental (dextran sodium sulfate-induced) colitis in RAGE knockout and wild-type mice were performed. The -374T/A RAGE promotor single nucleotide polymorphism (SNP) was negatively associated with CD (odds ratio = 0.708, 95% confidence interval = 0.535-0.938, P = 0.016) and with stenosis (OR = 0.627, P = 0.04) in the German sample. Transmission disequilibrium testing confirmed an undertransmission of the -374A allele. Serum sRAGE levels were higher in patients in complete remission of the -374AA/TA group (1,975 ± 299 pg/ml; -374TT group: 1,310 ± 153 pg/ml SE, P < 0.05) and showed a trend toward decreased levels in CD patients with active disease compared with CD patients in remission. Further in vitro and in vivo studies indicated that an increase of sRAGE ameliorates inflammation. The -429T/C and the G82S polymorphism were not associated with CD. The -374T/A RAGE polymorphism leading to facilitated RAGE gene transcription may to some degree protect from developing a stricturing subphenotype of CD, most likely by increasing levels of sRAGE, which neutralizes proinflammatory mediators.

Long-term efficacy and safety of double balloon enteroscopy--prospective and retrospective data from a single center study.

OBJECTIVE: Double balloon enteroscopy (DBE) has evolved as one of the most innovative and fast spreading endoscopic procedures in the last decade. With increasing experience of performing endoscopic procedures in the mid gut outside the operating room it is necessary to investigate the effectiveness of DBE regarding therapeutic consequences, long-term efficacy as well as safety. MATERIAL AND METHODS: To address this we retrospectively analyzed all DBE performed over a period of 2 years at our department. Furthermore, in order to evaluate long-term effectiveness of DBE procedures we performed a follow-up analysis on all patients, whose DBE procedure was at least 6 months ago. In addition, 100 consecutive patients who underwent DBE were questioned regarding procedure associated complaints using a standardized questionnaire. RESULTS: Retrospective analysis of all DBE procedures performed in our department before November 2006 (n = 545) revealed an overall diagnostic yield of 39.7% and a therapeutic yield of 31.1%. The overall number of major complications accounted to 0.9%. Follow-up analysis revealed a long-term effect of endoscopic interventions in more than 50%, while in those patients with an initially negative DBE long-term follow-up only revealed symptom explaining findings in 17% with the majority of the other patients being asymptomatic during follow-up. Regarding patient related complaints the prospective analysis showed that DBE procedures in general are well tolerated with the most common complaint being meteorism. CONCLUSIONS: DBE showed to be a relatively safe and well tolerated procedure. However, more sensitive algorithms are needed to enhance the therapeutic results.

Terminal signal: anti-inflammatory effects of α-melanocyte-stimulating hormone related peptides beyond the pharmacophore.

During the last two decades a significant number of investigations has established the fact that α-Melanocyte-stimulating hormone (α-MSH) is a potent anti-inflammatory mediator. The anti-inflammatory effects of α-MSH can be elicited via melanocortin receptors (MC-Rs) broadly expressed in a number of tissues ranging from the central nervous system to cells of the immune system and on resident somatic cells of peripheral tissues. α-MSH affects various pathways regulating inflammatory responses such as NF-κB activation, expression of adhesion molecules, inflammatory cytokines, chemokine receptors, T-cell proliferation and activity and inflammatory cell migration. In vivo α-MSH has been shown to be anti-inflammatory as well in animal models of fever, irritant and allergic contact dermatitis, cutaneous vasculitis, fibrosis, in ocular, gastrointestinal, brain and allergic airway inflammation and arthritis. A broad range of effects of α-MSH exerted beyond the field of inflammation, its pigmentory capacity being only the most visible aspect, has been one of the major impediments limiting the use of α-MSH in human inflammatory disorders. Interestingly KPV, C-terminal tripeptide of α-MSH, which lacks the entire sequence motif required for binding to any of the known MC-Rs, retains almost all of the anti-inflammatory capacity of the full hormone, but in its activities display a lack of any pigmentory action. While the exact signaling mechanism utilized by KPV and related peptides currently is unknown it has been demonstrated already that significant similarities between anti-inflammatory signaling of α-MSH and those short peptides exist. These α-MSH related tripeptides thus may be useful alternatives for anti-inflammatory peptide therapy. KdPT, a derivative of KPV corresponding to IL-1ß(193-195), currently is emerging as another tripeptide with potent anti-inflammatory effects. A more limited spectrum of biologic activities, potentially advantageous physicochemical, pharmacokinetic and pharmacodynamic properties as well as the expectation of low costs for pharmaceutical production make these agents interesting candidates for the treatment of immune-mediated inflammatory skin and bowel diseases, allergic asthma and arthritis.

Resistance of chemokine receptor 6-deficient mice to Yersinia enterocolitica infection: evidence of defective M-cell formation in vivo.

M cells, specialized cells within Peyer's patches (PPs), are reduced in number in chemokine receptor 6 (CCR6)-deficient mice. The pathogenic microorganism Yersinia enterocolitica exploits M cells for the purpose of mucosal tissue invasion exclusively through PPs. The aim of this study was to evaluate the course of yersiniosis in CCR6-deficient mice and to investigate whether these mice might be used as an in vivo model to determine M-cell function. After oral challenge with Y. enterocolitica, control mice suffered from lethal septic infection whereas CCR6-deficient mice showed very limited symptoms of infection. Immunohistochemical analysis demonstrated PP invasion by Y. enterocolitica in control mice whereas no bacteria could be found in CCR6-deficient mice. In addition, a significant induction of proinflammatory cytokines could be found in control mice whereas proinflammatory cytokine levels in CCR6-deficient mice remained unchanged. In contrast, intraperitoneal infection resulted in severe systemic yersiniosis in both mouse groups. Abrogated oral Y. enterocolitica infection in CCR6-deficient mice demonstrates the importance of CCR6 expression in the physiological and pathological immune responses generated within PPs by influencing M-cell differentiation, underscoring the important role of M cells in the process of microbial uptake. CCR6-deficient mice may therefore represent a suitable model for the study of M-cell function in vivo.