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.

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BACKGROUND: We tested a panel of novel serological anti-glycan antibodies including the previously unpublished anti-laminarin IgA (Anti-L) and anti-chitin IgA (Anti-C) carbohydrate antibodies for the presence in Crohn's disease (CD) patients, diagnosis and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.

Serum anti-glycan antibodies predict complicated Crohn's disease behavior: a cohort study.

BACKGROUND: A high proportion of patients with Crohn's 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(R) 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.

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 biomarker's 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.

Intact cell adhesion to glycan microarrays.

A rapid and reproducible method was developed to detect and quantify carbohydrate-mediated cell adhesion to glycans arrayed on glass slides. Monosaccharides and oligosaccharides were covalently attached to glass slides in 1.7-mm-diameter spots (200 spots/slide) separated by a Teflon gasket. Primary chicken hepatocytes, which constitutively express a C-type lectin that binds to nonreducing terminal N-acetylglucosamine residues, were labeled with a fluorescent dye and incubated in 1.3-microL aliquots on the glycosylated spots. After incubating to allow cell adhesion, nonadherent cells were removed by immersing the slide in phosphate buffered saline, inverting, and centrifuging in a sealed custom acrylic chamber so that cells on the derivatized spots were subjected to a uniform and controlled centrifugal detachment force while avoiding an air-liquid interface. After centrifugation, adherent cells were fixed in place and detected by fluorescent imaging. Chicken hepatocytes bound to nonreducing terminal GlcNAc residues in different linkages and orientations but not to nonreducing terminal galactose or N-acetylgalactosamine residues. Addition of soluble GlcNAc (but not Gal) prior to incubation reduced cell adhesion to background levels. Extension of the method to CD4+ human T-cells on a 45-glycan diversity array revealed specific adhesion to the sialyl Lewis x structure. The described method is a robust approach to quantify selective cell adhesion using a wide variety of glycans and may contribute to the repertoire of tools for the study of glycomics.