title: Systematic epitope analysis of the p26 EIAV core protein.
abstract: The major core protein of equine infectious anemia virus (EIAV), p26, is one of the primary immunogenic structural proteins during a persistent infection of horses and is highly conserved among antigenically variants of viral isolates. In order to investigate its immune profile in more detail for a better diagnostic, an epitope mapping was carried out by means of two libraries of overlapping peptide fragments prepared by simultaneous and parallel SPPS on derivatized cellulose membranes (SPOT synthesis). Polyclonal equine sera from infected horses were used for the biological assay. Particularly two promising continuous epitopes (NAMRHL and MYACRD) were localized on the C-terminal extreme of p26, region 194-222. A cyclic synthetic fragment of 29 amino acid residues containing the identified epitopes was designed and studied. A significant conformational change towards a helical structure was observed when the peptide was cyclized by a bridge between Cys198 and Cys218. This observation correlated with an improvement of its ability to be recognized by specific antibodies in an EIA (Enzyme-linked Immunosorbent assay). These results suggest that the conformationally restricted synthetic antigen adequately mimics the native structure of this region of p26 core protein.
authors: Laboratorio de Inmunoquímica, Dirección de Sanidad Animal, Ministerio de la Producción, Bv. Pellegrini 3100, Santa Fe, Argentina.
authors: Adriana
authors: A
authors: Soutullo
authors: María N
authors: MN
authors: Santi
authors: Juan C
authors: JC
authors: Perin
authors: Leila M
authors: LM
authors: Beltramini
authors: Ileana Malan
authors: IM
authors: Borel
authors: Ronald
authors: R
authors: Frank
authors: Georgina G
authors: GG
authors: Tonarelli
mesh_terms: D000595:Amino Acid Sequence; D018604:Epitope Mapping / Q000379:methods*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000032:analysis; D040081:Protein Array Analysis; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D014758:Viral Core Proteins / Q000032:analysis* / Q000737:chemistry / Q000276:immunology* / Q000378:metabolism
chemical_list: D010446:Peptide Fragments; D014758:Viral Core Proteins; C117895:equine infectious anemia virus, p26