title: Molecular cloning and characterisation of Ts8B1, Ts8B2 and Ts8B3, three new members of the Taenia solium metacestode 8 kDa diagnostic antigen family.
abstract: Antibody screening of a lambdaZAP-XR Taenia solium metacestode cDNA library yielded a clone (Ts8B1), with an insert of 345 bp, and an open reading frame of 258 bp, that coded for a protein with 85 amino acid residues. Alignment of the predicted amino acid sequence with sequences from SWISSPROT revealed an 88% identity with TcA5.5, a 10 kDa immunodiagnostic antigen of T. crassiceps, 75% identity with CyDA a T. solium metacestode antigen, 40-50% identity with several variants of the 8 kDa subunit of antigen B of Echinococcus spp. and with members of the T. solium metacestode 8 kDa antigen family. Two other Ts8B1 related molecules, Ts8B2 and Ts8B3, were identified in the metacestode cDNA library by PCR, coding for 85 and 66 amino acid polypeptides, respectively. Both Ts8B1 and Ts8B2 were characterized as E/S antigens through their subcellular localisation in the secretory membrane system when expressed in NRK cells. The three cDNA inserts were expressed, purified and probed in enzyme-linked immunosorbent assays (ELISA) with sera and cerebro-spinal fluid from patients with confirmed neurocysticercosis, and with sera from pigs infected with T. solium. The most promising antigen, Ts8B2, performed with a sensitivity of 96.8% and specificity of 93.1% in the detection of active NCC when using serum samples in the assay and performed similarly in the porcine system. The implications of these findings are discussed.
authors.affiliation: Instituto de Salud Carlos III, Centro Nacional de Microbiología, 28220 Majadahonda, Madrid, Spain.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Ferrer
authors.forename: Pedro
authors.initials: P
authors.lastname: Bonay
authors.forename: Mildred
authors.initials: M
authors.lastname: Foster-Cuevas
authors.forename: Luis Miguel
authors.initials: LM
authors.lastname: González
authors.forename: Iris
authors.initials: I
authors.lastname: Dávila
authors.forename: María Milagros
authors.initials: MM
authors.lastname: Cortéz
authors.forename: Leslie J S
authors.initials: LJ
authors.lastname: Harrison
authors.forename: R Michael E
authors.initials: RM
authors.lastname: Parkhouse
authors.forename: Teresa
authors.initials: T
authors.lastname: Gárate
mesh_terms: D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood; D000947:Antigens, Helminth / Q000235:genetics* / Q000276:immunology / Q000302:isolation & purification; D002460:Cell Line; D002462:Cell Membrane / Q000737:chemistry; D003001:Cloning, Molecular; D003551:Cysticercosis / Q000175:diagnosis*; D018509:DNA, Helminth / Q000737:chemistry / Q000235:genetics; D004446:Echinococcus / Q000235:genetics; D015723:Gene Library; D006801:Humans; D008969:Molecular Sequence Data; D011817:Rabbits; D051381:Rats; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013347:Subcellular Fractions / Q000737:chemistry; D013552:Swine; D041201:Taenia solium / Q000235:genetics*
chemical_list: D000909:Antibodies, Helminth; D000947:Antigens, Helminth; D018509:DNA, Helminth; D011994:Recombinant Proteins