title: Identification of a differentially expressed Echinococcus multilocularis protein Em6 potentially related to antigen 5 of Echinococcus granulosus.
abstract: By a strategy of differential immunological screening of an expression library constructed from adult Echinococcus multilocularis parasites, a partial cDNA sequence encoding a protein termed Em6 was isolated. This molecule displayed high sequence homology to the recombinant antigen 'Eg6' which was previously described as an immunogenic epitope of antigen 5 of E. granulosus. Further Em6 sequences and the corresponding sequences from a cattle isolate of E. granulosus were obtained by a PCR approach. By immunoblot analyses using affinity purified antibodies, expression of Em6 in fertile cysts producing protoscoleces of the E. multilocularis metacestode stage was observed. However, Em6 was absent in non-fertile metacestodes. The demonstration of a protein in E. multilocularis displaying identities to 'antigen 6' of E. granulosus could potentially contribute to the future elucidation of the relationship between antigen 5 and 'antigen 6' in the genus Echinococcus, and shed some lights on the performance of serodiagnostic assays for hydatid disease based on the respective antigens.
authors.affiliation: Institute of Parasitology, University of Berne, Länggass-Strasse 122, 3012-Berne, Switzerland.
authors.forename: M
authors.initials: M
authors.lastname: Siles-Lucas
authors.forename: B
authors.initials: B
authors.lastname: Gottstein
authors.forename: R S
authors.initials: RS
authors.lastname: Felleisen
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood; D000947:Antigens, Helminth / Q000276:immunology*; D001483:Base Sequence; D015153:Blotting, Western; D002417:Cattle; D018076:DNA, Complementary; D004285:Dogs; D004446:Echinococcus / Q000737:chemistry* / Q000276:immunology; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000276:immunology; D005849:Gerbillinae; D015801:Helminth Proteins / Q000235:genetics* / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011817:Rabbits; D017421:Sequence Analysis; D017386:Sequence Homology, Amino Acid
chemical_list: D000909:Antibodies, Helminth; D000947:Antigens, Helminth; D018076:DNA, Complementary; C115843:Em6 protein, Echinococcus multilocularis; D000939:Epitopes; D015801:Helminth Proteins