title: Identification of classical swine fever virus protein E2 as a target for cytotoxic T cells by using mRNA-transfected antigen-presenting cells.
abstract: Vaccination of pigs against Classical swine fever virus (CSFV) by using live-virus vaccines induces early protection before detectable humoral immune responses. Immunological analyses indicate that this is associated with T-cell activation, underlining the importance of targeting cytotoxic T-lymphocyte (CTL) responses for vaccine improvement. Antigen-presenting cells (APCs) transfected with mRNA encoding structural protein E2 or non-structural viral proteins NS3-NS4A were used to identify viral genes encoding CTL epitopes. Monocyte-derived dendritic cells (DCs) and fibrocytes served as the APCs. In vitro translation of the mRNA and microscopic analysis of transfected cells demonstrated that E2 and NS3-NS4A could be identified. APCs transfected with either of the mRNA molecules restimulated CSFV-specific T cells to produce gamma interferon and specific cytotoxic activity against CSFV-infected target cells. The presence of CTL epitopes on E2 was confirmed by using d/d-haplotype MAX cells expressing E2 constitutively as target cells in d/d-haplotype CTL assays. A potent CTL activity against E2 was detected early (1-3 weeks) after CSFV challenge. This work corroborates the existence of CTL epitopes within the non-structural protein domain NS3-NS4A of CSFV. Furthermore, epitopes on the E2 protein can also now be classified as targets for CTLs, having important implications for vaccine design, especially subunit vaccines. As for the use of mRNA-transfected APCs, this represents a simple and efficient method to identify viral genes encoding CTL epitopes in outbred populations.
authors.affiliation: Institute of Virology and Immunoprophylaxis (IVI), Postfach, CH-3147 Mittelhäusern, Switzerland.
authors.forename: M
authors.initials: M
authors.lastname: Ceppi
authors.affiliation: Animal Sciences Group, 8200 Lelystad, The Netherlands.
authors.forename: M G M
authors.initials: MGM
authors.lastname: de Bruin
authors.affiliation: Institute of Virology and Immunoprophylaxis (IVI), Postfach, CH-3147 Mittelhäusern, Switzerland.
authors.forename: T
authors.initials: T
authors.lastname: Seuberlich
authors.affiliation: Institute of Virology and Immunoprophylaxis (IVI), Postfach, CH-3147 Mittelhäusern, Switzerland.
authors.forename: C
authors.initials: C
authors.lastname: Balmelli
authors.affiliation: Organic Chemistry, Auf der Morgenstelle 18, D-72076 Tübingen, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Pascolo
authors.affiliation: Institute of Virology and Immunoprophylaxis (IVI), Postfach, CH-3147 Mittelhäusern, Switzerland.
authors.forename: N
authors.initials: N
authors.lastname: Ruggli
authors.affiliation: Friedrich-Loeffler-Institut, Paul-Ehrlich-Straße 28, D-72076 Tübingen, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Wienhold
authors.affiliation: Institute of Virology and Immunoprophylaxis (IVI), Postfach, CH-3147 Mittelhäusern, Switzerland.
authors.forename: J D
authors.initials: JD
authors.lastname: Tratschin
authors.affiliation: Institute of Virology and Immunoprophylaxis (IVI), Postfach, CH-3147 Mittelhäusern, Switzerland.
authors.forename: K C
authors.initials: KC
authors.lastname: McCullough
authors.affiliation: Institute of Virology and Immunoprophylaxis (IVI), Postfach, CH-3147 Mittelhäusern, Switzerland.
authors.forename: A
authors.initials: A
authors.lastname: Summerfield
mesh_terms: D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology* / Q000821:virology; D002461:Cell Line, Transformed; D006691:Classical Swine Fever / Q000276:immunology / Q000517:prevention & control; D006692:Classical Swine Fever Virus / Q000235:genetics / Q000276:immunology; D003602:Cytotoxicity, Immunologic; D003713:Dendritic Cells / Q000276:immunology / Q000821:virology; D018984:Epitopes, T-Lymphocyte / Q000276:immunology; D009000:Monocytes / Q000276:immunology; D012333:RNA, Messenger / Q000235:genetics* / Q000276:immunology; D013552:Swine; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014162:Transfection; D014759:Viral Envelope Proteins / Q000235:genetics / Q000276:immunology*
chemical_list: D018984:Epitopes, T-Lymphocyte; D012333:RNA, Messenger; D014759:Viral Envelope Proteins; C087086:glycoprotein E2, classical swine fever virus