Dietary intake of inulin-type fructans in active and inactive Crohn’s disease and healthy controls: a case-control study

Background and Aims: Prebiotic inulin-type fructans are widely consumed in the diet and may have contrasting effects in Crohn’s disease by stimulating gut microbiota and/or by generating functional gastrointestinal symptoms. The aim of this study was to measure fructan and oligofructose intakes in patients with active and inactive Crohn’s disease compared with healthy controls. Methods: Patients with active Crohn’s disease (n=98), inactive Crohn’s (n=99) and healthy controls (n=106) were recruited to a case-control study. Dietary intake of inulin-type fructans was measured using a specific food frequency questionnaire and was compared between the three groups and between patients with different disease phenotypes (Montreal classification). Associations between intakes and disease activity (Harvey Bradshaw Index, HBI) were also undertaken. Results: Patients with active Crohn’s disease had lower fructan intakes (median 2.9 g/d, IQR 1.8) than those with inactive Crohn’s (3.6 g/d, 2.1, P=0.036) or controls (3.9 g/d, 2.1, P=0.003) and lower oligofructose intakes (2.8 g/d, 1.8) than inactive Crohn’s (3.5 g/d, 2.2, P=0.048) or controls (3.8 g/d, 2.1, P=0.003). There were no differences in intakes related to disease site or behaviour. There were negative correlations between HBI wellbeing score and fructan intake (ρ=-0.154, P=0.03) and oligofructose intake (ρ=-0.156, P=0.028) and for the HBI abdominal pain score and fructan (ρ=-0.164, P=0.021) and oligofructose intake (ρ=-0.157, P=0.027). Conclusions: Patients with active Crohn’s disease consume lower quantities of fructans and oligofructose than their inactive counterparts and healthy controls. The impact of lower intakes of prebiotic fructans on gut microbiota are unknown and warrant further research

Diagnostic and clinical significance of Crohn’s disease-specific anti-MZGP2 pancreatic antibodies by a novel ELISA:New anti-MZGP2 ELISA in Crohn’s

The recent identification of the pancreas major zymogen granule membrane glycoprotein 2 (MZGP2) as the major autoantigen of pancreatic autoantibody (PAB) has led to the appreciation of anti-MZGP2 antibodies as specific markers of Crohn’s disease (CrD). We have recently developed new, robust, highly sensitive and specific IgA and IgG anti-MZGP2 antibody ELISAs and assessed their clinical relevance in the largest inflammatory bowel disease (IBD) cohort tested to date for anti-MZGP2 antibodies. In contrast to currently available anti-MZGP2 ELISAs, the new QUANTA Lite® MZGP2 ELISA (INOVA Diagnostics, San Diego, CA) utilizes the eukaryotically-expressed specific isoform 4 of human GP2 UniProtKB: P55259. A total of 832 sera were studied including 617 consecutive IBD patients (323 CrD and 294 UC) under regular follow-up in a tertiary centre, 112 patients with various diseases, and 103 healthy blood donors. The new ELISA’s calculated AUC was 0.5968, 95% CI (0.5552, 0.6383) for IgA anti-MZGP2 [CD vs non-CD (UC plus controls)] and 0.6236, 95% CI (0.5813, 0.6659) for IgG anti-MZGP2. The sensitivity of IgA anti-MZGP2 for CrD in the IBD population was 15% and the specificity was 98% (95, 99), while the sensitivity and specificity of IgG anti-MZGP2 was 27% and 97%. IgA and IgG anti-MZGP2 combined testing led to a sensitivity of 31% and specificity of 96%. Positivity for either ASCA (IgA or IgG) or anti-MZGP2 (IgA or IgG) showed a sensitivity of 75% (70, 80) and specificity of 84% (79, 89). Of clinical relevance, IgA anti- MZGP2 antibodies were more prevalent in patients with early disease onset (Montreal classification A1, p=0.011), while patients with localised colonic disease were less likely to be IgG anti-MZGP2 positive. Anti-MZGP2 positive patients more frequently had extensive disease with ileal involvement and stricture formation. Patients with longer disease duration were more likely to have IgG anti-MZGP2 or IgA ASCA antibodies. In conclusion, the new IgA and IgG anti-MZGP2 antibody ELISAs allow accurate autoantibody determination, and can be used as a tool to study the clinical significance and utility of these autoantibodies in patients with IBD

E. coli Induced Experimental Model of Primary Biliary Cirrhosis: At Last

Recurrent urinary tract infections (UTI) have been considered potential triggers of primary biliary cirrhosis (PBC), an autoimmune cholestatic liver disease characterised by progressive destruction of intrahepatic bile ducts. Additional support for the link made between PBC and UTI was based on early observations of recurrent episodes of bacteriuria in female patients with PBC. A series of large epidemiological studies demonstrated a strong correlation between recurrent UTI and PBC, initiating a series of studies investigating the role of Escherichia coli (E. coli, the most prevalent organism isolated in women with UTI) as a trigger of PBC. Immunological evidence of B- and T-cell cross-reactive responses implicating PBC-specific autoantigens and E. coli mimics have been clearly demonstrated, adding support to the notion that E. coli is a potential infectious inducer of PBC in susceptible individuals. One of the major limitations in proving the E. coli/PBC association was the lack of reliable E. coli-infected animal models of PBC. This review provides an overview of the evidence linking this infectious agent with PBC and discusses the pros and cons of a recently developed E. coli-infected animal model of PBC

Diagnostic and clinical significance of Crohn's disease-specific pancreatic anti-GP2 and anti-CUZD1 antibodies

AbstractPancreatic autoantibodies (PAB) targeting GP2 and CUZD1 are Crohn’s disease (CrD)-markers. The clinical significance of anti-GP2 antibodies has been assessed, but that of anti-CUZD1 remains elusive. The aim of the study was to assess the clinical utility of anti-CUZD1/anti-GP2 by novel cell-based indirect immunofluorescence (IIF) assays in CrD.A total of 212 CrD and 249 UC patients followed up at a London IBD centre were investigated to simultaneously detect PABs, anti-GP2 and anti-CUZD1 by IIF using primate pancreatic tissue, and HEK293 over-expressing CUZD1 or GP2.Overall, 88 (41.5%) CrDs compared to 26 (10.4%) UCs (p&lt;0.001) tested positive for IgA and/or IgG anti-GP2 and/or anti-CUZD1 antibodies, while ASCA were found in 67.5% CrDs versus 19.2% UCs (p&lt;0.0001); ASCA and/or PAB (anti-GP2 or anti-CUZD1) were detected in 76% CrD versus 34% UC patients. IgG anti-GP2 antibodies were less prevalent in L2 phenotype (p=0.002) and more prevalent in patients with stricturing disease (p=0.0418), even when a higher cut-off (≥1000 RU) was used (p=0.0396). Also, anti-GP2 IgG positive CrD patients had younger age of disease onset. IgA and/or IgG ASCA and anti-GP2 IgG antibody positive CrDs had younger onset of disease (p&lt;0.0001), were more likely to have both ileal and colonic disease (p&lt;0.0001) and had more stricturing (p&lt;0.0001) than seronegative patients. Clinical correlates were not found for anti-CUZD1 positivity.PAB testing increases ASCA’s serological sensitivity for CrD. Anti-GP2 detection, in isolation or in combination with ASCA, stratify CrD patients who phenotypically are characterised by a much younger onset of disease, extensive and stricturing behaviour.</jats:p

Ileal inflammation may trigger the development of GP2-specific pancreatic autoantibodies in patients with Crohn's disease

Why zymogen glycoprotein 2 (GP2), the Crohn's disease (CD)-specific pancreatic autoantigen, is the major target of humoral autoimmunity in inflammatory bowel diseases (IBD) is uknown. Recent evidence demonstrates that GP2 is also present on the apical surface of microfold (M) intestinal cells. As the colon lacks GP2-rich M cells, we assumed that patients with colonic CD are seronegative for anti-GP2. Anti-GP2 antibodies were tested in 225 CDs, including 45 patients with colonic location (L2), 45 with terminal ileum (L1) and 135 with ileocolonic involvement; 225 patients with ulcerative colitis (UC) were also tested. Anti-GP2 reactivity was detected in 59 (26.2%) CDs and 15 (6.7%) UCs (

Randomised, double-blind, placebo-controlled trial of fructo-oligosaccharides in active Crohn's disease

The commensal intestinal microbiota drive the inflammation associated with Crohn's disease. However, bacteria such as bifidobacteria and Faecalibacterium prausnitzii appear to be immunoregulatory. In healthy subjects the intestinal microbiota are influenced by prebiotic carbohydrates such as fructo-oligosaccharides (FOS). Preliminary data suggest that FOS increase faecal bifidobacteria, induce immunoregulatory dendritic cell (DC) responses and reduce disease activity in patients with Crohn's disease

Smokers with active Crohn's disease have a clinically relevant dysbiosis of the gastrointestinal microbiota

Patients with Crohn's disease (CD) have an intestinal dysbiosis with components of the microbiota exerting differential immune effects. Smoking is associated with an increased incidence of CD, more frequent relapse, and greater burden of surgery. This study aimed to investigate the association between smoking and the intestinal microbiota in patients with active CD

Bioinformatic and immunological analysis reveals lack of support for measles virus related mimicry in Crohn's disease

Background: A link between measles virus and Crohn's disease (CD) has been postulated. We assessed through bioinformatic and immunological approaches whether measles is implicated in CD induction, through molecular mimicry. Methods: The BLAST2p program was used to identify amino acid sequence similarities between five measles virus and 56 intestinal proteins. Antibody responses to measles/human mimics were tested by an in-house ELISA using serum samples from 50 patients with CD, 50 with ulcerative colitis (UC), and 38 matched healthy controls (HCs). Results: We identified 15 sets of significant (>70%) local amino acid homologies from two measles antigens, hemagglutinin-neuraminidase and fusion-glycoprotein, and ten human intestinal proteins. Reactivity to at least one measles 15 meric mimicking peptide was present in 27 out of 50 (54%) of patients with CD, 24 out of 50 (48%) with UC (CD versus UC, p = 0.68), and 13 out of 38 (34.2%) HCs (CD versus HC, p = 0.08). Double reactivity to at least one measles/human pair was present in four out of 50 (8%) patients with CD, three out of 50 (6%) with UC (p = 0.99), and in three out of 38 (7.9%) HCs (p>0.05 for all). Titration experiments yielded different extinction curves for anti-measles and anti-human intestinal double-reactive antibodies. Epitope prediction algorithms and three-dimensional modeling provided bioinformatic confirmation for the observed antigenicity of the main measles virus epitopic regions. Conclusions: Measles sequences mimicking intestinal proteins are frequent targets of antibody responses in patients with CD, but this reactivity lacks disease specificity and does not initiate cross-reactive responses to intestinal mimics. We conclude that there is no involvement of measles/human molecular mimicry in the etiopathogenesis of CD