Nir Dotan

New serological markers in inflammatory bowel disease are associated with complicated disease behaviour

Background and aims: Several antibodies have been associated with Crohn’s disease and are associated with distinct clinical phenotypes. The aim of this study was to determine whether a panel of new antibodies against bacterial peptides and glycans could help in differentiating inflammatory bowel disease (IBD), and whether they were associated with particular clinical manifestations. Methods: Antibodies against a mannan epitope of Saccharomyces cerevisiae (gASCA), laminaribioside (ALCA), chitobioside (ACCA), mannobioside (AMCA), outer membrane porins (Omp) and the atypical perinuclear antineutrophilic cytoplasmic antibody (pANCA) were tested in serum samples of 1225 IBD patients, 200 healthy controls and 113 patients with non-IBD gastrointestinal inflammation. Antibody responses were correlated with the type of disease and clinical characteristics. Results: 76% of Crohn’s disease patients had at least one of the tested antibodies. For differentiation between Crohn’s disease and ulcerative colitis, the combination of gASCA and pANCA was most accurate. For differentiation between IBD, healthy controls and non-IBD gastrointestinal inflammation, the combination of gASCA, pANCA and ALCA had the best accuracy. Increasing amounts and levels of antibody responses against gASCA, ALCA, ACCA, AMCA and Omp were associated with more complicated disease behaviour (44.7% versus 53.6% versus 71.1% versus 82.0%, p < 0.001), and a higher frequency of Crohn’s disease-related abdominal surgery (38.5% versus 48.8% versus 60.7% versus 75.4%, p < 0.001). Conclusions: Using this new panel of serological markers, the number and magnitude of immune responses to different microbial antigens were shown to be associated with the severity of the disease. With regard to the predictive role of serological markers, further prospective longitudinal studies are necessary.

Novel Anti-Glycan Antibodies Related to Inflammatory Bowel Disease Diagnosis and Phenotype

OBJECTIVES:We sought to evaluate whether two novel immunoglobulin A (IgA) cell wall polysaccharide antibodies, anti-laminarin (anti-L) and anti-chitin (anti-C), aid in the diagnosis and phenotype differentiation of Crohns disease (CD) and ulcerative colitis (UC).METHODS:A cohort of 818 individuals with inflammatory bowel disease (IBD; 517 CD and 301 UC) from two IBD tertiary referral centers, with median ages of 33 and 39 years, respectively, and disease duration of 8.9 years, were phenotyped using the Montreal classification, and analyzed for seven anti-glycan antibodies (gASCA (anti-Saccharomyces cerevisiae) IgG, gASCA IgA, anti-chitobioside (GlcNAc(β1,4)GlcNAc(β)), anti-laminaribioside (Glc(β1,3)Glb(β)), anti-mannobioside (Man(α1,3)Man(α)), anti-L, and anti-C) and perinuclear atypical neutrophil cytoplasmic antibodies (pANCA).RESULTS:In the CD patient population, 73% were positive for ≥1 anti-glycan antibody. All glycan markers were specific for CD (85.4–97.7%) and more prevalent in CD vs. UC (P<0.0015). gASCA IgG and IgA best differentiated CD from UC followed by anti-L (area under the curve 0.818, 0.815, and 0.702, respectively). The addition of anti-L and anti-C to gASCA IgG and pANCA improved discrimination between CD and UC (P<0.001). Adding anti-L to gASCA and pANCA differentiated colonic CD and UC (P=0.02). An increasing number of positive antibodies was associated with early CD onset, penetrating phenotype, perianal disease, and the need for surgery (P<0.001). Anti-L was associated with ileocolonic CD (odds ratio (OR) 2.28, 95% confidence interval (CI) 1.40–3.69; P=0.001), and anti-C with penetrating (OR 2.75, 95% CI 1.50–5.04; P=0.001) and perianal disease (OR 1.95, 95% CI 1.06–3.59; P=0.03).CONCLUSIONS:Anti-L and anti-C improve differentiation between CD and UC. Anti-L may also differentiate between isolated colonic CD and UC. Both anti-L and anti-C are independently associated with a more aggressive CD phenotype.

Association of the novel serologic anti-glycan antibodies anti-laminarin and anti-chitin with complicated Crohn's disease behavior.

Background: We tested a panel of novel serological anti‐glycan antibodies including the previously unpublished anti‐laminarin IgA (Anti‐L) and anti‐chitin IgA (Anti‐C) carbohydrate antibodies for the presence in Crohns disease (CD) patients, diagnosis and differentiation of CD, association with complicated disease behavior, and marker stability over time. Methods: The presence of Anti‐L, Anti‐C, anti‐chitobioside IgA (ACCA), anti‐laminaribioside IgG (ALCA), anti‐mannobioside IgG (AMCA), and anti‐Saccaromyces cervisiae IgG (gASCA) carbohydrate antibodies were tested in serum samples from 824 participants (363 CD, 130 ulcerative colitis [UC], 74 other gastrointestinal diseases, and 257 noninflammatory bowel/gastrointestinal disease controls) of the German IBD‐network by enzyme‐linked immunosorbent assay (ELISA; Glycominds, Lod, Israel) and for perinuclear antineutrophil cytoplasmic antibody (pANCA) by immunofluorescence. Results: In all, 77.4% of the CD patients were positive for at least 1 of the anti‐glycan antibodies. gASCA or the combination of gASCA/pANCA remained most accurate for the diagnosis of CD, but the combined use of the antibodies improved differentiation of CD from UC. Several single markers as well as an increasing antibody response were independently linked to a severe disease phenotype, as shown for the occurrence of complications, CD‐related surgery, early disease onset, and ileal disease location. This was observed for both quantitative and qualitative antibody responses. The antibody status remained stable over time in most IBD patients. Conclusions: A panel of anti‐glycan antibodies including the novel Anti‐L and Anti‐C may aid in differentiation of CD from UC, is associated with complicated CD behavior and IBD‐related surgery, and is stable over time in a large patient cohort. Inflamm Bowel Dis 2009

Serum anti-glycan antibodies predict complicated Crohn's disease behavior: A cohort study†

Background: A high proportion of patients with Crohns disease (CD) over time develop complications like fistulae and strictures, requiring surgery. We tested a panel of antiglycan antibodies for predicting the occurrence of complications and CD‐related surgery in an adult patient cohort. Methods: Serum samples of 149 CD patients of the German inflammatory bowel disease (IBD) network were tested for the presence of anti‐laminarin IgA (Anti‐L), anti‐chitin IgA (Anti‐C), anti‐chitobioside IgA (ACCA), anti‐laminaribioside IgG (ALCA), anti‐mannobioside IgG (AMCA), and anti‐Saccaromyces cerevisiae IgG (gASCA) carbohydrate antibodies by enzyme‐linked immunosorbent assay (ELISA) (IBDX® panel, Glycominds, Lod, Israel) in a blinded fashion. Clinical data were available on occurrence of complicated disease or CD‐related surgery as well as disease activity, onset, and location. Results: The median follow‐up of the patients without any previous complication or surgery at time of sample procurement was 53.7 months. Overall, 26.3% developed a complication and 17.1% underwent CD‐related surgery, respectively. Positivity for gASCA, AMCA, ACCA, and Anti‐L alone or an increasing frequency of positive serum antibodies independently predicted a faster progression toward a more severe disease course. Once a complication or surgery had occurred only positivity for Anti‐L or more than 3 markers out of the whole panel indicated progression to an additional surgery or complication. The antibody status of most patients remained stable over time. Conclusions: This is the first study showing the clinical value of serum antiglycan antibodies for prediction of a more complicated disease course in adult patients with CD. (Inflamm Bowel Dis 2010)

Anti-α-glucose–based glycan IgM antibodies predict relapse activity in multiple sclerosis after the first neurological event

Background There is no specific serum-based biomarker for the diagnosis or prognosis of relapsing-remitting multiple sclerosis (RRMS). Objective We investigated whether levels of IgM antibodies to Glc(α1,4)Glc(α) (GAGA4) or to a panel of four glucose-based glycans could differentiate MS from other neurological diseases (OND) or predict risk of early relapse following first presentation (FP) of RRMS. Methods Retrospective analysis of 440 sera samples of three cohorts: A) FP-RRMS (n = 44), OND (n = 44); B) FP-RRMS (n = 167), OND (n = 85); and C) FP (n = 100). Anti-GAGA4 IgM levels were measured by enzyme immunoassay in cohort-A and cohort-B. Cohort-C IgM antibodies to glucose-based glycan panel were measured by immunofluorescence. Results FP-RRMS had higher levels of anti-GAGA4 IgM than OND patients (cohort-A, P = 0.01; cohort-B, P = 0.0001). Sensitivity and specificity were 27% and 97% for cohort-A; and 26% and 90% for cohort-B, respectively. In cohort-C, 58 patients experienced early relapse (<24 months), 31 had late relapse (≥24 months), and 11 did not experience second attack during follow-up. Kaplan–Meier curves demonstrated decrease in time to next relapse for patients positive for the antibody panel (P = 0.02, log rank). Conclusions Serum anti-GAGA4 IgM discerns FP-RRMS patients from OND patients. Higher levels of serum anti-α-glucose IgM in FP patients predict imminent early relapse.

Serum anti-GAGA4 IgM antibodies differentiate relapsing remitting and secondary progressive multiple sclerosis from primary progressive multiple sclerosis and other neurological diseases.

The serum level of IgM antibodies against Glc(alpha1,4)Glc(alpha) (GAGA4) is higher in relapsing remitting multiple sclerosis (RRMS) compared to other neurological disease (OND) patients and healthy controls (HC). Detecting the level of anti-GAGA4 antibody by enzyme immunoassay and total IgM, we confirmed that anti-GAGA4 IgM can differentiate RRMS from OND patients and HC. Moreover, secondary progressive MS (SPMS) and RRMS patients have similar levels of anti-GAGA4 demonstrating the biomarkers presence throughout the disease. Interestingly, the anti-GAGA4 assay may also differentiate between primary progressive MS (PPMS) and RRMS/SPMS patients, since nearly all PPMS patients were negative for the assay.

Characterization of Changes in Serum Anti-Glycan Antibodies in Crohn's Disease – a Longitudinal Analysis

Introduction Anti-glycan antibodies are a promising tool for differential diagnosis and disease stratification of patients with Crohns disease (CD). We longitudinally assessed level and status changes of anti-glycan antibodies over time in individual CD patients as well as determinants of this phenomenon. Methods 859 serum samples derived from a cohort of 253 inflammatory bowel disease (IBD) patients (207 CD, 46 ulcerative colitis (UC)) were tested for the presence of anti-laminarin (Anti-L), anti-chitin (Anti-C), anti-chitobioside (ACCA), anti-laminaribioside (ALCA), anti-mannobioside (AMCA) and anti-Saccharomyces cerevisiae (gASCA) antibodies by ELISA. All patients had at least two and up to eleven serum samples taken during the disease course. Results Median follow-up time for CD was 17.4 months (Interquartile range (IQR) 8.0, 31.6 months) and for UC 10.9 months (IQR 4.9, 21.0 months). In a subgroup of CD subjects marked changes in the overall immune response (quartile sum score) and levels of individual markers were observed over time. The marker status (positive versus negative) remained widely stable. Neither clinical phenotype nor NOD2 genotype was associated with the observed fluctuations. In a longitudinal analysis neither changes in disease activity nor CD behavior led to alterations in the levels of the glycan markers. The ability of the panel to discriminate CD from UC or its association with CD phenotypes remained stable during follow-up. In the serum of UC patients neither significant level nor status changes were observed. Conclusions While the levels of anti-glycan antibodies fluctuate in a subgroup of CD patients the antibody status is widely stable over time.

390 The Novel Anti-Glycan Antibodies Anti-L and Anti-C in Conjunction with ALCA, ACCA, gASCA and AMCA Predict Early Development of Fistulae, Stenoses and Surgery in Patients with Crohn's Disease: A Prospective Analysis

The Novel Anti-Glycan Antibodies Anti-L and Anti-C in Conjunction with ALCA, ACCA, gASCA and AMCA Predict Early Development of Fistulae, Stenoses and Surgery in Patients with Crohns Disease: A Prospective Analysis Florian Rieder, Alexandra Wolf, Stephan Schleder, Andrea Dirmeier, Ulrike Strauch, Florian Obermeier, Larissa Spector, Ella Fire, Jennifer Yarden, Gerhard Rogler, Nir Dotan, Frank Klebl

Serum Biomarker gMS-Classifier2: Predicting Conversion to Clinically Definite Multiple Sclerosis

Background Anti-glycan antibodies can be found in autoimmune diseases. IgM against glycan P63 was identified in clinically isolated syndromes (CIS) and included in gMS-Classifier2, an algorithm designed with the aim of identifying patients at risk of a second demyelinating attack. Objective To determine the value of gMS-Classifier2 as an early and independent predictor of conversion to clinically definite multiple sclerosis (CDMS). Methods Data were prospectively acquired from a CIS cohort. gMS-Classifier2 was determined in patients first seen between 1995 and 2007 with ≥ two 200 µL serum aliquots (N = 249). The primary endpoint was time to conversion to CDMS at two years, the factor tested was gMS-Classifier2 status (positive/negative) or units; other exploratory time points were 5 years and total time of follow-up. Results Seventy-five patients (30.1%) were gMS-Classifier2 positive. Conversion to CDMS occurred in 31/75 (41.3%) of positive and 45/174 (25.9%) of negative patients (p = 0.017) at two years. Median time to CDMS was 37.8 months (95% CI 10.4–65.3) for positive and 83.9 months (95% CI 57.5–110.5) for negative patients. gMS-Classifier2 status predicted conversion to CDMS within two years of follow-up (HR = 1.8, 95% CI 1.1–2.8; p = 0.014). gMS-Classifier2 units were also independent predictors when tested with either Barkhof criteria and OCB (HR = 1.2, CI 1.0–1.5, p = 0.020) or with T2 lesions and OCB (HR = 1.3, CI 1.1–1.5, p = 0.008). Similar results were obtained at 5 years of follow-up. Discrimination measures showed a significant change in the area under the curve (ΔAUC) when adding gMS-Classifier2 to a model with either Barkhof criteria (ΔAUC 0.0415, p = 0.012) or number of T2 lesions (ΔAUC 0.0467, p = 0.009), but not when OCB were added to these models. Conclusions gMS-Classifier2 is an independent predictor of early conversion to CDMS and could be of clinical relevance, particularly in cases in which OCB are not available.