title: Identification of a novel 19 kDa Echinococcus granulosus antigen.
abstract: By screening an Echinococcus granulosus cDNA library with IgG4 from patients with active cystic echinococcosis (CE), we identified a cDNA encoding a protein of 19.0 kDa (Eg19). Eg19, in 12% SDS-PAGE in reducing and non-reducing conditions, showed several bands between 19 and 100 kDa. Immunoblotting (IB) analysis detected total IgG, IgG1 and IgG4 specific to the 38/40 kDa band of Eg19 in the 10% of patients' sera. The percentage of total IgG, IgG1 and IgG4-positive sera were significantly higher in sera from patients with active disease and cyst in multiple sites than from patients with inactive disease and cyst in the liver (P<10(-4)). ELISA analysis disclosed that during the follow-up anti-Eg19 antibody concentration decreased over the course of treatment in sera from patients with cured disease. Even if Eg19 appear to have no benefit in the diagnosis of the disease, our data, confirming the presence of antigens inducing both IgG1 and IgG4 during active development of CE, suggest that Eg19 might be a marker of disease status.
authors.affiliation: Department of Infectious, Parasitic and Immune-Mediated Diseases, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Delunardo
authors.forename: Elena
authors.initials: E
authors.lastname: Ortona
authors.forename: Paola
authors.initials: P
authors.lastname: Margutti
authors.forename: Maurizio
authors.initials: M
authors.lastname: Perdicchio
authors.forename: Davide
authors.initials: D
authors.lastname: Vacirca
authors.forename: Antonella
authors.initials: A
authors.lastname: Teggi
authors.forename: Maurizio
authors.initials: M
authors.lastname: Sorice
authors.forename: Alessandra
authors.initials: A
authors.lastname: Siracusano
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood / Q000276:immunology; D000947:Antigens, Helminth / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D015415:Biomarkers / Q000097:blood; D004443:Echinococcosis / Q000175:diagnosis* / Q000276:immunology / Q000469:parasitology; D048209:Echinococcus granulosus / Q000235:genetics / Q000276:immunology*; D015723:Gene Library; D015801:Helminth Proteins / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology; D008969:Molecular Sequence Data; D008970:Molecular Weight
chemical_list: D000909:Antibodies, Helminth; D000947:Antigens, Helminth; D015415:Biomarkers; D015801:Helminth Proteins; D007074:Immunoglobulin G