title: Shared and non-shared antigens from three different extracts of the metacestode of Echinococcus granulosus.
abstract: Hydatid cyst fluid (HCF), somatic antigens (S-Ag) and excretory-secretory products (ES-Ag) of Echinococcus granulosus protoscoleces are used as the main antigenic sources for immunodiagnosis of human and dog echinococcosis. In order to determine their non-shared as well as their shared antigenic components, these extracts were studied by ELISA-inhibition and immunoblot-inhibition. Assays were carried out using homologous rabbit polyclonal antisera, human sera from individuals with surgically confirmed hydatidosis, and sera from dogs naturally infected with E. granulosus. High levels of cross-reactivity were observed for all antigenic extracts, but especially for ES-Ag and S-Ag. Canine antibodies evidenced lesser avidity for their specific antigens than antibodies from human origin. The major antigenic components shared by HCF, S-Ag, and ES-Ag have apparent molecular masses of 4-6, 20-24, 52, 80, and 100-104 kDa, including doublets of 41/45, 54/57, and 65/68 kDa. Non-shared polypeptides of each antigenic extract of E. granulosus were identified, having apparent masses of 108 and 78 kDa for HCF, of 124, 94, 83, and 75 kDa for S-Ag, and of 89, 66, 42, 39, 37, and 35 kDa for ES-Ag.
authors.affiliation: Departamento de Inmunología, Microbiología y Parasitología, Facultad de Farmacia, Universidad del País Vasco, Vitoria, Spain.
authors.forename: David
authors.initials: D
authors.lastname: Carmena
authors.forename: Jorge
authors.initials: J
authors.lastname: Martínez
authors.forename: Aitziber
authors.initials: A
authors.lastname: Benito
authors.forename: Jorge A
authors.initials: JA
authors.lastname: Guisantes
mesh_terms: D000818:Animals; D000947:Antigens, Helminth / Q000276:immunology*; D003429:Cross Reactions; D020420:Cyst Fluid / Q000737:chemistry / Q000276:immunology; D004283:Dog Diseases / Q000276:immunology; D004285:Dogs; D004443:Echinococcosis / Q000276:immunology / Q000662:veterinary; D004444:Echinococcosis, Hepatic / Q000276:immunology*; D048209:Echinococcus granulosus / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D015801:Helminth Proteins / Q000276:immunology*; D006801:Humans; D015151:Immunoblotting; D011817:Rabbits; D012756:Sheep
chemical_list: D000947:Antigens, Helminth; D015801:Helminth Proteins