title: [Evaluation of a purified antigen for the diagnosis of toxocariosis].
abstract: Toxocarosis is a zoonotic disease caused by the ingestion of infective eggs of Toxocara spp. The diagnosis is based on the detection of antibodies in serum or other biological fluids. One of the current serological techniques for the diagnosis of toxocariasis is ELISA using excretory - secretory antigens of third stage larvae (ES/L3). These antigens are glycoproteins, which originate in the secretory organs of the parasite and are non species-specific. Sera from patients with other helminthiases and non- parasitic diseases were used to evaluate the specificity of ELISA using the excretory - secretory antigen (ES/L3). The reactivity of these sera was between 11 and 70%. Western blot using patients' sera revealed that the glycoprotein triplet having a molecular weight of 120 kDa was responsible for cross-reactivity. With these results, and for the purpose of purifying the antigen, ion exchange chromatography was performed. When the sera from patients with various parasitic and non-parasitic diseases were analyzed with the purified antigen ES/ L3, they were only reactive between 10 to 20%. The sensitivity of the ELISA test determined by program Epidat 3.0 for the two antigens was 100%, but the following differences in specificity were observed: 84% for the total antigen ES/L3 and 99% for purified ES/L3. Using the ES/L3 purified antigen, it can be considered that the reactive sera, with compatible symptoms correspond to patients who are or were parasitized with Toxocara canis.
authors.affiliation: Departamento de Parasitología, Ciudad Autónoma de Buenos Aires, Argentina. gsantillan@anlis.gov.ar
authors.forename: Graciela
authors.initials: G
authors.lastname: Santillán
authors.forename: Vanesa
authors.initials: V
authors.lastname: Bastin
authors.forename: Graciela
authors.initials: G
authors.lastname: Céspedes
authors.forename: Adriana
authors.initials: A
authors.lastname: Monkiewicz
mesh_terms: D000947:Antigens, Helminth / Q000097:blood*; D006801:Humans; D012698:Serologic Tests / Q000379:methods; D014120:Toxocariasis / Q000097:blood* / Q000175:diagnosis*
chemical_list: D000947:Antigens, Helminth