title: Development of a latex agglutination test with recombinant variant surface glycoprotein for serodiagnosis of surra.
abstract: Serodiagnosis of surra is commonly performed with the CATT/Trypanosoma evansi direct agglutination test. This antibody detection test is based on lyophilised bloodstream form trypanosomes propagated in rats and presenting the predominant variant surface glycoprotein (VSG) RoTat 1.2 on their surface. Recently, the N-terminal fragment of VSG RoTat 1.2 has been expressed as a recombinant protein in the yeast Pichia pastoris and showed diagnostic potential in ELISA. This recombinant antigen has now been incorporated in a latex agglutination test, the rLATEX/T. evansi. In this study, we compared the diagnostic accuracy of rLATEX/T. evansi and CATT/T. evansi with immune trypanolysis (TL) as reference test on a total of 1717 sera from camels, horses, bovines, water buffaloes, dogs and sheep. The rLATEX/T. evansi displayed a slightly better agreement with TL than CATT/T. evansi (kappa [κ] respectively 0.84 and 0.72). The sensitivities of rLATEX/T. evansi (84.2%, 95% CI 80.8-87.1) and CATT/T. evansi (84.0%, 95% CI 80.6-87.0) were similar, but rLATEX/T. evansi was significantly more specific (97.7%, 95% CI 96.7-98.4) than CATT/T. evansi (89.4%; 95% CI 87.6-91.1). We consider the rLATEX/T. evansi an alternative for the CATT/T. evansi, with the advantage that the use of a purified recombinant antigen leads to a more standardised diagnostic test with an improved specificity. Moreover, it eliminates the use of laboratory animals and can be easily scaled-up, e.g. in biofermentors.
authors.affiliation: Department of Biomedical Sciences, Unit of Parasite Diagnostics, Institute of Tropical Medicine, Nationalestraat 155, B-2000 Antwerp, Belgium; Laboratory for Molecular Plant Physiology and Biotechnology, Department of Biology, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium. Electronic address: sroge@itg.be.
authors.forename: S
authors.initials: S
authors.lastname: Rogé
authors.affiliation: Production and Applied Technology Unit, Institute of Tropical Medicine, Nationalestraat 155, B-2000 Antwerp, Belgium.
authors.forename: R
authors.initials: R
authors.lastname: Baelmans
authors.affiliation: Animal Health Service, Food and Agriculture Organization of the United Nations (FAO), Viale delle Terme di Caracalla, 10532 Rome, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Claes
authors.affiliation: Institut de Recherche pour le Développement, Unite Mixte de Recherche UMR177 - Intertryp, Campus International de Baillarguet TA A-17/G, 34398 Montpellier, France.
authors.forename: V
authors.initials: V
authors.lastname: Lejon
authors.affiliation: Laboratory for Molecular Plant Physiology and Biotechnology, Department of Biology, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium.
authors.forename: Y
authors.initials: Y
authors.lastname: Guisez
authors.affiliation: Production and Applied Technology Unit, Institute of Tropical Medicine, Nationalestraat 155, B-2000 Antwerp, Belgium.
authors.forename: D
authors.initials: D
authors.lastname: Jacquet
authors.affiliation: Department of Biomedical Sciences, Unit of Parasite Diagnostics, Institute of Tropical Medicine, Nationalestraat 155, B-2000 Antwerp, Belgium.
authors.forename: P
authors.initials: P
authors.lastname: Büscher
mesh_terms: D000372:Agglutination Tests / Q000662:veterinary; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood*; D000953:Antigens, Protozoan / Q000276:immunology*; D002020:Buffaloes; D002162:Camelus / Q000469:parasitology*; D002417:Cattle; D004285:Dogs; D006736:Horses; D007841:Latex Fixation Tests / Q000662:veterinary; D008562:Membrane Glycoproteins / Q000276:immunology*; D015800:Protozoan Proteins / Q000276:immunology; D051381:Rats; D011994:Recombinant Proteins; D012680:Sensitivity and Specificity; D012756:Sheep; D014345:Trypanosoma / Q000276:immunology*; D014352:Trypanosomiasis / Q000662:veterinary*
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D008562:Membrane Glycoproteins; D015800:Protozoan Proteins; D011994:Recombinant Proteins
keywords: Antibody detection; Domestic animals; RoTat 1.2; Serodiagnosis; Surra; Trypanosoma evansi