title: Usefulness of concanavalin-A non-binding fraction of Strongyloides venezuelensis larvae to detect IgG and IgA in human strongyloidiasis.
abstract: Glycosylated components from Strongyloides have an important role in parasite establishment and host recognition of these substances. Considering the sugar-binding capacity of lectins, such as concanavalin-A (Con-A), IgG and IgA detection in serum samples from strongyloidiasis patients was tested using different antigenic preparations. The total saline extract (SE) of Strongyloides venezuelensis filariform larvae was fractionated in Con-A column to obtain Con-A unbound (Con-A UF) and Con-A bound (Con-A BF) fractions. Sensitivity (Se), specificity (Sp), area under the ROC curve (AUC), likelihood ratio (LR), and correlation coefficients were calculated. Con-A UF showed the highest diagnostic parameters for IgG detection (Se 95.0%, Sp 92.5%, AUC 0.99, LR 12.7) and high correlation (r = 0.700) with SE. Con-A fractions did not clearly demonstrate any usefulness for IgA detection. In conclusion, the results obtained demonstrate that Con-A UF is an important source of specific peptides efficient to detect IgG in strongyloidiasis immunodiagnosis.
authors.affiliation: Departamento de Imunologia, Microbiologia e Parasitologia, Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, 38400-902, Uberlândia, MG, Brazil.
authors.forename: Henrique Tomaz
authors.initials: HT
authors.lastname: Gonzaga
authors.forename: Vanessa da Silva
authors.initials: Vda S
authors.lastname: Ribeiro
authors.forename: Jair Pereira
authors.initials: JP
authors.lastname: Cunha-Júnior
authors.forename: Marlene Tiduko
authors.initials: MT
authors.lastname: Ueta
authors.forename: Julia Maria
authors.initials: JM
authors.lastname: Costa-Cruz
mesh_terms: D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood*; D000947:Antigens, Helminth / Q000302:isolation & purification*; D005591:Chemical Fractionation; D019411:Clinical Laboratory Techniques / Q000379:methods*; D003208:Concanavalin A / Q000378:metabolism; D006801:Humans; D007118:Immunoassay / Q000379:methods; D007070:Immunoglobulin A / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D007814:Larva / Q000737:chemistry / Q000276:immunology; D010274:Parasitology / Q000379:methods*; D011485:Protein Binding; D012372:ROC Curve; D012680:Sensitivity and Specificity; D013321:Strongyloides / Q000737:chemistry* / Q000276:immunology; D013322:Strongyloidiasis / Q000175:diagnosis*
chemical_list: D000909:Antibodies, Helminth; D000947:Antigens, Helminth; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D003208:Concanavalin A