The mouse and human IGSF6 (DORA) genes map to the inflammatory bowel disease 1 locus and are embedded in an intron of a gene of unknown function.

We have previously characterized IGSF6 (DORA), a novel member of the immunoglobulin superfamily (IGSF) from human and rat expressed in dendritic and myeloid cells. Using a probe from the open reading frame of the rat cDNA, we isolated a cosmid which contains the entire mouse gene. By comparative analysis and reverse transcriptase polymerase chain reaction, we defined the intron/exon structure and the mRNA of the mouse gene and, with respect to human BAC clones, the human gene. The genes span 10 kb (mouse) and 12 kb (human), with six exons arranged in a manner similar to other members of the IGSF. All intron/exon boundaries follow the GT-AG rule. Expression of the mouse Igsf6 gene is restricted to cells of the immune system, particularly macrophages. Northern blot revealed a single mRNA of 2.5 kb, in contrast to the human gene which is expressed as two mRNAs of 1 and 2.5 kb. The human and mouse genes were localized to a locus associated with inflammatory bowel disease. Analysis of the flanking regions of the Igsf6 gene revealed the presence of an unrelated gene, transcribed from the opposite strand of the DNA and oriented such that the Igsf6 gene is encoded entirely within an intron. An identical organization is seen in human. This gene of unknown function is transcribed and processed, contains homologues in Caenorhabditis elegans and prokaryotes, and is expressed in most organs in the mouse.

Adjustment to inflammatory bowel disease: The relative influence of illness perceptions and coping

Background: The Common Sense Model (CSM) of illness representations was used in the current study to examine the relative contribution of illness perceptions and coping strategies in explaining adjustment to inflammatory bowel disease (IBD). Methods: Participants were 80 adults consecutively attending an outpatients' clinic with a diagnosis of either Crohn's disease or ulcerative colitis. Respondents completed and returned a questionnaire booklet that assessed illness perceptions, coping, and adjustment. Adjustment was measured from the perspectives of psychological distress, quality of life, and functional independence. Results: Illness perceptions (particularly perception of consequences of IBD) were uniformly the most consistent variables explaining adjustment to IBD. Coping did not significantly add to predicting adjustment once illness perceptions were controlled for and therefore did not mediate the relationship between illness perceptions and adjustment, as proposed in the CSM. Conclusions: The results suggest the importance of addressing illness perceptions in developing appropriate psychological interventions for IBD.

Inflammatory bowel disease, gut bacteria and probiotic therapy

Crohn's disease (CD) and ulcerative colitis (UC) are the two major forms of inflammatory bowel disease (IBD) and both diseases lead to high morbidity and health care costs. Complex interactions between the immune system, enteric commensal bacteria and host genotype are thought to underlie the development of IBD although the precise aetiology of this group of diseases is still unknown. The understanding of the composition and complexity of the normal gut microbiota has been greatly aided by the use of molecular methods and is likely to be further increased with the advent of metagenomics and metatranscriptomics approaches, which will allow an increasingly more holistic assessment of the microbiome with respect to both diversity and function of the commensal gut microbiota. Studies thus far have shown that the intestinal microbiota drives the development of the gut immune system and can induce immune homeostasis as well as contribute to the development of IBD. Probiotics which deliver some of the beneficial immunomodulatory effects of the commensal gut microbiota and induce immune homeostasis have been proposed as a suitable treatment for mild to moderate IBD. This review provides an overview over the current understanding of the commensal gut microbiota, its interactions with the mucosal immune system and its capacity to induce both gut homeostasis as well as dysregulation of the immune system. Bacterial-host events, including interactions with pattern recognition receptors (PRRs) expressed on epithelial cells and dendritic cells (DCs) and the resultant impact on immune responses at mucosal surfaces will be discussed. (C) 2009 Elsevier GmbH. All rights reserved.

Balancing Inflammatory, Lipid, and Xenobiotic Signaling Pathways by VSL#3, a Biotherapeutic Agent, in the Treatment of Inflammatory Bowel Disease

Background: The interleukin 10 knockout mouse (IL10-KO) is a model of human inflammatory bowel disease (IBD) used to Study host microbial interactions and the action of potential therapeutics. Using Affymetrix data analysis, important signaling pathways and transcription factors relevant to gut inflammation and antiinflammatory probiotics were identified.

Methods: Affymetrix microarray analysis on both wildtype (WT) and IL10-KO mice orally administered with and without the probiotic VSL#3 was performed and the results validated by real-time polymerase chain reaction (PCR), immunocytochemistry, proteomics, and histopathology. Changes in metabolically active bacteria were assessed with denaturing gradient gel electrophoresis (DGGE).

Results: Inflammation in IL10-KO mice was characterized by differential regulation of inflammatory, nuclear receptor, lipid, and xenobiotic signaling pathways. Probiotic intervention resulted in downregulation of CXCL9 (fold change [FC] = -3.98, false discovery rate [FDR] = 0.019), CXCL10 (FC = -4.83, FDR = 0.0008), CCL5 (FC -3.47 FDR = 0.017), T-cell activation (Itgal [FC = -4.72, FDR = 0.00009], Itgae [FC = -2.54 FDR = 0.0044]) and the autophagy gene IRGM (FC = -1.94, FDR = 0.01), a recently identified susceptibility gene in human IBD. Consistent with a marked reduction in integrins, probiotic treatment decreased the number of CCL5+ CD3+ double-positive T Cells and upregulated galectin2, which triggers apoptosis of activated T cells. Importantly, genes associated with lipid and PPAR signaling (PPAR alpha [FC = 2.36, FDR = 0.043], PPARGC1 alpha [FC 2.58, FDR = 0.016], Nrld2 [FC = 3.11, FDR = 0.0067]) were also upregulated. Altered microbial diversity was noted in probiotic-treated mice.

Conclusions: Bioinformatics analysis revealed important immune response. phagocytic and inflammatory pathways dominated by elevation of T-helper cell 1 type (TH1) transcription factors in IL10-KO mice. Probiotic intervention resulted in a site-specific reduction of these pathways but importantly upregulated PPAR, xenobiotic, and lipid signaling genes. potential antagonists of NF-kappa B inflammatory pathways.

Anti-TNF antibody-induced psoriasiform skin lesions in patients with inflammatory bowel disease are characterised by interferon-γ-expressing Th1 cells and IL-17A/IL-22-expressing Th17 cells and respond to anti-IL-12/IL-23 antibody treatment

Background We analysed incidence, predictors, histological features and specific treatment options of anti-tumour necrosis factor alpha (TNF-alpha) antibody-induced psoriasiform skin lesions in patients with inflammatory bowel diseases (IBD).

Design Patients with IBD were prospectively screened for anti-TNF-induced psoriasiform skin lesions. Patients were genotyped for IL23R and IL12B variants. Skin lesions were examined for infiltrating Th1 and Th17 cells. Patients with severe lesions were treated with the anti-interleukin (IL)-12/IL-23 p40 antibody ustekinumab.

Results Among 434 anti-TNF-treated patients with IBD, 21 (4.8%) developed psoriasiform skin lesions. Multiple logistic regression revealed smoking (p=0.007; OR 4.24, 95% CI 1.55 to 13.60) and an increased body mass index (p=0.029; OR 1.12, 95% CI 1.01 to 1.24) as main predictors for these lesions. Nine patients with Crohn's disease and with severe psoriasiform lesions and/or anti-TNF antibody-induced alopecia were successfully treated with the anti-p40-IL-12/IL-23 antibody ustekinumab (response rate 100%). Skin lesions were histologically characterised by infiltrates of IL-17A/IL-22-secreting T helper 17 (Th17) cells and interferon (IFN)-gamma-secreting Th1 cells and IFN-alpha-expressing cells. IL-17A expression was significantly stronger in patients requiring ustekinumab than in patients responding to topical therapy (p=0.001). IL23R genotyping suggests disease-modifying effects of rs11209026 (p.Arg381Gln) and rs7530511 (p.Leu310Pro) in patients requiring ustekinumab.

Conclusions New onset psoriasiform skin lesions develop in nearly 5% of anti-TNF-treated patients with IBD. We identified smoking as a main risk factor for developing these lesions. Anti-TNF-induced psoriasiform skin lesions are characterised by Th17 and Th1 cell infiltrates. The number of IL-17A-expressing T cells correlates with the severity of skin lesions. Anti-IL-12/IL23 antibody therapy is a highly effective therapy for these lesions.

The fungal microbiota of de-novo paediatric inflammatory bowel disease

Inflammatory bowel disease (IBD) is characterised by an inappropriate chronic immune response against resident gut microbes. This may be on account of distinct changes in the gut microbiota termed as dysbiosis. The role of fungi in this altered luminal environment has been scarcely reported. We studied the fungal microbiome in de-novo paediatric IBD patients utilising next generation sequencing and compared with adult disease and normal controls. We report a distinct difference in fungal species with Ascomycota predominating in control subjects compared to Basidiomycota dominance in children with IBD, which could be as a result of altered tolerance in these patients. 

Randomized comparison of unfractionated heparin with corticosteroids in severe active inflammatory bowel disease

BACKGROUND: Heparin therapy may be effective in steroid resistant inflammatory bowel disease.

AIM: A randomized pilot study, to compare unfractionated heparin as a first-line therapy with corticosteroids in colonic inflammatory bowel disease.

METHODS: Twenty patients with severe inflammatory bowel disease (ulcerative colitis, n=17; Crohn's colitis, n=3) were randomized to either intravenous heparin for 5 days, followed by subcutaneous heparin for 5 weeks (n=8), or high-dose intravenous hydrocortisone for 5 days followed by oral prednisolone 40 mg daily, reducing by 5 mg per day each week (n=12). After 5 days, non-responders in each treatment group were commenced on combination therapy. Response to therapy was monitored by: clinical disease activity (ulcerative colitis: Truelove and Witt Index; Crohn's colitis: Harvey and Bradshaw Index), stool frequency, serum C-reactive protein and alpha1 acid glycoprotein, endoscopic and histopathological grading.

RESULTS: The response rates were similar in both treatment groups: clinical activity index (heparin vs. steroid; 75% vs. 67%; P=0.23), stool frequency (75% vs. 67%; P=0.61), endoscopic (75% vs. 67%; P=0.4) and histopathological grading (63% vs. 50%; P=0.67). Both treatments were well-tolerated with no serious adverse events.

CONCLUSION: Heparin as a first line therapy is as effective as corticosteroids in the treatment of colonic inflammatory bowel disease. Large multicentre randomized comparative studies are required to determine the role of heparin in the management of inflammatory bowel disease.

A20 Regulation of NF-{kappa}B: Perspectives for Inflammatory Lung Disease.

Persistent activation of NF-B is central to the pathogenesis of many inflammatory lung disorders including Cystic Fibrosis, Asthma and Chronic Obstructive Pulmonary Disease. A20 is an endogenous negative regulator of NF-B signalling which has been widely described in autoimmune and inflammatory disorders including Diabetes and Crohn’s disease, but which has received little attention in terms of chronic lung disorders. This review examines the existing body of research on A20 regulation of NF-B signalling and details the mechanism and regulation of A20 action focusing, where possible, on pulmonary inflammation. A20 and its associated signalling molecules are highlighted as being of potential therapeutic interest for the treatment of inflammatory disorders and a proposed model of A20 activity in inflammatory lung disease is provided.

What is the significance of muciphages in colorectal biopsies?

Muciphages (mucin-containing macrophages), first described in 1966 by Azzopardi & Evans, are a common feature of biopsies of large intestinal mucosa, even in the absence of other abnormalities such as active inflammation or evidence of chronic inflammatory bowel disease. Should they be mentioned in diagnostic reports? Do muciphages reliably indicate previous mucosal disease, now quiescent? In the following articles, Salto-Tellez & Price review what is known about muciphages and conclude that they reflect previous occult and clinically unimportant mucosal damage and that, in an otherwise normal colorectal mucosa, they have no diagnostic significance; and Shepherd draws attention to a wide range of clinically much more significant mucosal infiltrates that could be mistakenly regarded as muciphages and thus overlooked.

Crossing the eukaryote-prokaryote divide:A ubiquitin homolog in the human commensal bacterium Bacteroides fragilis

The resident microbiota of the human gastrointestinal (GI) tract is comprised of ~2,000 bacterial species, the majority of which are anaerobes. Colonization of the GI tract is important for normal development of the immune system and provides a reservoir of catabolic enzymes that degrade ingested plant polysaccharides. Bacteroides fragilis is an important member of the microbiota because it contributes to T helper cell development, but is also the most frequently isolated Gram-negative anaerobe from clinical infections. During the annotation of the B. fragilis genome sequence, we identified a gene predicted to encode a homolog of the eukaryotic protein modifier, ubiquitin. Previously, ubiquitin had only been found in eukaryotes, indicating the bacterial acquisition as a potential inter-kingdom horizontal gene transfer event. Here we discuss the possible roles of B. fragilis ubiquitin and the implications for health and disease. © 2012 Landes Bioscience

Post-Translational Inhibition of IP-10 Secretion in IEC by Probiotic Bacteria: Impact on Chronic Inflammation

Background: Clinical and experimental studies suggest that the probiotic mixture VSL#3 has protective activities in the context of inflammatory bowel disease (IBD). The aim of the study was to reveal bacterial strain-specific molecular mechanisms underlying the anti-inflammatory potential of VSL#3 in intestinal epithelial cells (IEC).

Methodology/Principal Findings: VSL#3 inhibited TNF-induced secretion of the T-cell chemokine interferon-inducible protein (IP-10) in Mode-K cells. Lactobacillus casei (L. casei) cell surface proteins were identified as active anti-inflammatory components of VSL#3. Interestingly, L. casei failed to block TNF-induced IP-10 promoter activity or IP-10 gene transcription at the mRNA expression level but completely inhibited IP-10 protein secretion as well as IP-10-mediated T-cell transmigration. Kinetic studies, pulse-chase experiments and the use of a pharmacological inhibitor for the export machinery (brefeldin A) showed that L. casei did not impair initial IP-10 production but decreased intracellular IP-10 protein stability as a result of blocked IP-10 secretion. Although L. casei induced IP-10 ubiquitination, the inhibition of proteasomal or lysosomal degradation did not prevent the loss of intracellular IP-10. Most important for the mechanistic understanding, the inhibition of vesicular trafficking by 3-methyladenine (3-MA) inhibited IP-10 but not IL-6 expression, mimicking the inhibitory effects of L. casei. These findings suggest that L. casei impairs vesicular pathways important for the secretion of IP-10, followed by subsequent degradation of the proinflammatory chemokine. Feeding studies in TNF Delta ARE and IL-10(-/-) mice revealed a compartimentalized protection of VSL#3 on the development of cecal but not on ileal or colonic inflammation. Consistent with reduced tissue pathology in IL-10(-/-) mice, IP-10 protein expression was reduced in primary epithelial cells.

Conclusions/Significance: We demonstrate segment specific effects of probiotic intervention that correlate with reduced IP-10 protein expression in the native epithelium. Furthermore, we revealed post-translational degradation of IP-10 protein in IEC to be the molecular mechanism underlying the anti-inflammatory effect.