title: Evaluation of a di-O-methylated glycan as a potential antigenic target for the serodiagnosis of human toxocariasis.
abstract: Serodiagnosis of human toxocariasis is based on the detection of specific IgG antibodies by the enzyme-linked immunosorbent assay (ELISA) using Toxocara larvae excretory-secretory (TES) antigens, but its production is a laborious and time-consuming process being also limited by the availability of adult females of T. canis as source for ova to obtain larvae. Chemical synthesis of the di-O-methylated (DiM) glycan structure found in the TES antigens has provided material for studying the antibody reactivity in a range of mammalian hosts, showing reactivity with human IgM and IgG. In this study, we have evaluated the performance of the DiM glycan against a panel of sera including patients with toxocariasis (n = 60), patients with other helminth infections (n = 75) and healthy individuals (n = 94), showing that DiM is able to detect IgG antibodies with a sensitivity and specificity of 91·7% and 94·7%, respectively, with a very good agreement with the TES antigens (kappa = 0·825). However, cross-reactivity was observed in some sera from patients with ascariasis, hymenolepiasis and fascioliasis. These results show that the DiM glycan could be a promising antigenic tool for the serodiagnosis of human toxocariasis.
authors.affiliation: Laboratório de Soroepidemiologia e Imunobiologia do Instituto de Medicina Tropical de São Paulo, Universidade de São Paulo, São Paulo, Brasil.
authors.forename: G R
authors.initials: GR
authors.lastname: Elefant
authors.affiliation: Departamento de Microbiología Médica, Faculdad de Medicina, Universidad Nacional Mayor de San Marcos, Lima, Peru.
authors.forename: W H
authors.initials: WH
authors.lastname: Roldán
authors.affiliation: Department of Chemistry, University of Natural Resources and Life Sciences, Vienna, Austria.
authors.forename: A
authors.initials: A
authors.lastname: Seeböck
authors.affiliation: Department of Chemistry, University of Natural Resources and Life Sciences, Vienna, Austria.
authors.forename: P
authors.initials: P
authors.lastname: Kosma
mesh_terms: D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood*; D000947:Antigens, Helminth / Q000737:chemistry / Q000276:immunology; D016022:Case-Control Studies; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D015801:Helminth Proteins / Q000737:chemistry / Q000276:immunology; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D011134:Polysaccharides / Q000276:immunology; D012372:ROC Curve; D012698:Serologic Tests; D017166:Toxocara canis / Q000276:immunology*; D014120:Toxocariasis / Q000097:blood / Q000175:diagnosis* / Q000276:immunology
chemical_list: D000909:Antibodies, Helminth; D000947:Antigens, Helminth; D015801:Helminth Proteins; D007074:Immunoglobulin G; D011134:Polysaccharides; C045159:TES-26 protein, Toxocara canis
keywords: enzyme-linked immunosorbent assay; excretory-secretory antigen; immunoglobulin; serodiagnosis; toxocara canis; toxocariasis