title: Identification of two new antigen epitopes on the putative capsid protein encoded by torque teno sus virus type 1 ORF1.
abstract: Torque teno sus virus type 1 (TTSuV1) ORF1 is considered to encode the viral capsid (Cap) protein, which is crucial for the induction of TTSuV1-specific antibodies and protective immunity in the host. Eight monoclonal antibodies (mAbs) directed against the Cap protein were generated and biologically characterized. The immunoreactivity of the Cap protein expressed in transfected 293T cells for these mAbs was determined with an immunoperoxidase monolayer assay. The antigen epitopes of the Cap protein were mapped using these mAbs and truncated Cap proteins expressed in Escherichia coli. Fine epitope mapping was then performed with a panel of synthesized polypeptides. All the mAbs reacted with the Cap protein C fragment expressed in E. coli. One antigenic epitope of the Cap protein, which reacted with seven mAbs, had the polypeptide sequence (536)HPKYAGQGGGYTT(548), whereas another epitope recognized by the 1E9 mAb had the polypeptide sequence (549)EIGHQGITAASLR(561). It is interesting that the two new epitopes are adjacent, but mutually independent. This study should facilitate further investigation of the antigenic differences and enable the differential diagnosis of the virus.
authors.affiliation: Division of Swine Infectious Diseases, State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute of the Chinese Academy of Agricultural Sciences, Harbin 150001, China.
authors.forename: Jianbo
authors.initials: J
authors.lastname: Liu
authors.forename: Long
authors.initials: L
authors.lastname: Zhang
authors.forename: Liping
authors.initials: L
authors.lastname: Huang
authors.forename: Yanwu
authors.initials: Y
authors.lastname: Wei
authors.forename: Hongli
authors.initials: H
authors.lastname: Wu
authors.forename: Changming
authors.initials: C
authors.lastname: Liu
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal / Q000378:metabolism; D000914:Antibodies, Viral / Q000097:blood; D036022:Capsid Proteins / Q000737:chemistry / Q000235:genetics* / Q000276:immunology; D045744:Cell Line, Tumor; D004266:DNA Virus Infections / Q000175:diagnosis / Q000276:immunology / Q000662:veterinary* / Q000821:virology; D018604:Epitope Mapping; D000939:Epitopes / Q000235:genetics* / Q000276:immunology; D004926:Escherichia coli / Q000276:immunology; D005260:Female; D057809:HEK293 Cells; D006801:Humans; D051379:Mice; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology; D016415:Sequence Alignment; D013552:Swine; D013553:Swine Diseases / Q000175:diagnosis / Q000276:immunology / Q000821:virology*; D022783:Torque teno virus / Q000235:genetics* / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral; D036022:Capsid Proteins; D000939:Epitopes; D011994:Recombinant Proteins
keywords: Antigenepitope; Monoclonal antibody; Torque teno sus virus type 1 (TTSuV1)