title: An anionic synthetic sugar containing 6-SO3 -NAcGlc mimics the sulfated cruzipain epitope that plays a central role in immune recognition.
abstract: Cruzipain (Cz), the major cysteine proteinase of Trypanosoma cruzi, is a glycoprotein that contains sulfated high-mannose-type oligosaccharides. We have previously determined that these sulfate groups are targets of specific immune responses. In order to evaluate the structural requirements for antibody recognition of Cz, a systematic structure-activity study of the chemical characteristics needed for antibody binding to the Cz sulfated epitope was performed by immunoassays. With this aim, different synthesized molecules were coupled to the proteins BSA and aprotinin and confronted with (a) mouse sera specific for Cz and its carboxy-terminal (C-T) domain, (b) antibodies raised in rabbits immunized with Cz and its C-terminal domain and (c) IgGs purified from human Chagas disease sera. Our results indicate that a glucosamine containing an esterifying sulfate group in position O-6 and an N-acetyl group was the preferred epitope for the immune recognition of sera specific for Cz and its C-T domain. Although to a minor extent, other anionic compounds bearing sulfate groups in different positions and number as well as different anionic charged groups including carboxylated or phosphorylated monosaccharides, disaccharides and oligosaccharides were recognized. In conclusion, we found that synthetic anionic sugar conjugates containing N-acetyl d-glucosamine-6-sulfate sodium salt (GlcNAc6S) competitively inhibit the binding of affinity purified rabbit anti-C-T IgG to the C-T extension of Cz. Extending these findings to the context of natural infection, immune assays performed with Chagas disease serum confirmed that the structure of synthetic GlcNAc6S mimics the N-glycan-linked sulfated epitope displayed in the C-T domain of Cz.
authors:  CIHIDECAR (CONICET) Departamento de Química Orgánica, Universidad de Buenos Aires, Argentina Departamento de Investigación, Instituto Nacional de Parasitología 'Dr Mario Fatala Chaben', Buenos Aires, Argentina Laboratoire des Glucides, CNRS UMR 6219, Université de Picardie Jules Verne, Amiens, France.
authors: Alicia S
authors: AS
authors: Couto
authors:  CIHIDECAR (CONICET) Departamento de Química Orgánica, Universidad de Buenos Aires, Argentina Departamento de Investigación, Instituto Nacional de Parasitología 'Dr Mario Fatala Chaben', Buenos Aires, Argentina Laboratoire des Glucides, CNRS UMR 6219, Université de Picardie Jules Verne, Amiens, France.
authors: Luciana L
authors: LL
authors: Soprano
authors:  CIHIDECAR (CONICET) Departamento de Química Orgánica, Universidad de Buenos Aires, Argentina Departamento de Investigación, Instituto Nacional de Parasitología 'Dr Mario Fatala Chaben', Buenos Aires, Argentina Laboratoire des Glucides, CNRS UMR 6219, Université de Picardie Jules Verne, Amiens, France.
authors: Malena
authors: M
authors: Landoni
authors:  CIHIDECAR (CONICET) Departamento de Química Orgánica, Universidad de Buenos Aires, Argentina Departamento de Investigación, Instituto Nacional de Parasitología 'Dr Mario Fatala Chaben', Buenos Aires, Argentina Laboratoire des Glucides, CNRS UMR 6219, Université de Picardie Jules Verne, Amiens, France.
authors: Marilyne
authors: M
authors: Pourcelot
authors:  CIHIDECAR (CONICET) Departamento de Química Orgánica, Universidad de Buenos Aires, Argentina Departamento de Investigación, Instituto Nacional de Parasitología 'Dr Mario Fatala Chaben', Buenos Aires, Argentina Laboratoire des Glucides, CNRS UMR 6219, Université de Picardie Jules Verne, Amiens, France.
authors: Diana M
authors: DM
authors: Acosta
authors:  CIHIDECAR (CONICET) Departamento de Química Orgánica, Universidad de Buenos Aires, Argentina Departamento de Investigación, Instituto Nacional de Parasitología 'Dr Mario Fatala Chaben', Buenos Aires, Argentina Laboratoire des Glucides, CNRS UMR 6219, Université de Picardie Jules Verne, Amiens, France.
authors: Laurent
authors: L
authors: Bultel
authors:  CIHIDECAR (CONICET) Departamento de Química Orgánica, Universidad de Buenos Aires, Argentina Departamento de Investigación, Instituto Nacional de Parasitología 'Dr Mario Fatala Chaben', Buenos Aires, Argentina Laboratoire des Glucides, CNRS UMR 6219, Université de Picardie Jules Verne, Amiens, France.
authors: Juliana
authors: J
authors: Parente
authors:  CIHIDECAR (CONICET) Departamento de Química Orgánica, Universidad de Buenos Aires, Argentina Departamento de Investigación, Instituto Nacional de Parasitología 'Dr Mario Fatala Chaben', Buenos Aires, Argentina Laboratoire des Glucides, CNRS UMR 6219, Université de Picardie Jules Verne, Amiens, France.
authors: Maximiliano R
authors: MR
authors: Ferrero
authors:  CIHIDECAR (CONICET) Departamento de Química Orgánica, Universidad de Buenos Aires, Argentina Departamento de Investigación, Instituto Nacional de Parasitología 'Dr Mario Fatala Chaben', Buenos Aires, Argentina Laboratoire des Glucides, CNRS UMR 6219, Université de Picardie Jules Verne, Amiens, France.
authors: Maximilien
authors: M
authors: Barbier
authors:  CIHIDECAR (CONICET) Departamento de Química Orgánica, Universidad de Buenos Aires, Argentina Departamento de Investigación, Instituto Nacional de Parasitología 'Dr Mario Fatala Chaben', Buenos Aires, Argentina Laboratoire des Glucides, CNRS UMR 6219, Université de Picardie Jules Verne, Amiens, France.
authors: Christophe
authors: C
authors: Dussouy
authors:  CIHIDECAR (CONICET) Departamento de Química Orgánica, Universidad de Buenos Aires, Argentina Departamento de Investigación, Instituto Nacional de Parasitología 'Dr Mario Fatala Chaben', Buenos Aires, Argentina Laboratoire des Glucides, CNRS UMR 6219, Université de Picardie Jules Verne, Amiens, France.
authors: Mónica I
authors: MI
authors: Esteva
authors:  CIHIDECAR (CONICET) Departamento de Química Orgánica, Universidad de Buenos Aires, Argentina Departamento de Investigación, Instituto Nacional de Parasitología 'Dr Mario Fatala Chaben', Buenos Aires, Argentina Laboratoire des Glucides, CNRS UMR 6219, Université de Picardie Jules Verne, Amiens, France.
authors: José
authors: J
authors: Kovensky
authors:  CIHIDECAR (CONICET) Departamento de Química Orgánica, Universidad de Buenos Aires, Argentina Departamento de Investigación, Instituto Nacional de Parasitología 'Dr Mario Fatala Chaben', Buenos Aires, Argentina Laboratoire des Glucides, CNRS UMR 6219, Université de Picardie Jules Verne, Amiens, France.
authors: Vilma G
authors: VG
authors: Duschak
mesh_terms: D000117:Acetylglucosamine / Q000276:immunology*; D000293:Adolescent; D000328:Adult; D000818:Animals; D000838:Anions / Q000276:immunology*; D016022:Case-Control Studies; D014355:Chagas Disease / Q000097:blood / Q000276:immunology*; D003546:Cysteine Endopeptidases / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000276:immunology*; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008875:Middle Aged; D009844:Oligosaccharides / Q000276:immunology*; D015800:Protozoan Proteins; D011817:Rabbits; D012698:Serologic Tests; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013431:Sulfates / Q000276:immunology*; D014349:Trypanosoma cruzi / Q000276:immunology*; D055815:Young Adult
chemical_list: D000838:Anions; D000939:Epitopes; D007074:Immunoglobulin G; D009844:Oligosaccharides; D015800:Protozoan Proteins; D013431:Sulfates; D003546:Cysteine Endopeptidases; C063214:cruzipain; D000117:Acetylglucosamine