title: Role of porcine reproductive and respiratory syndrome virus nucleocapsid protein in induction of interleukin-10 and regulatory T-lymphocytes (Treg).
abstract: Porcine reproductive and respiratory syndrome virus (PRRSV) infection induces interleukin (IL)-10 production and increased numbers of PRRSV-specific regulatory T-lymphocytes in infected pigs. In the present study, the roles of the nucleocapsid (N) protein in induction of IL-10 and CD4(+)CD25(+)Foxp3(+) lymphocytes (T(reg)) were investigated. Transfection of porcine monocyte-derived dendritic cells (MoDCs) and pulmonary alveolar macrophages (PAMs) with a plasmid encoding N protein resulted in significant upregulation of IL-10 gene expression in the gene-transfected cells. Structural conformation, but not nuclear localization, of the expressed N protein was indicated to be essential for the ability to induce IL-10. Furthermore, the presence of recombinant N proteins in cultured PBMCs increased the number of IL-10-producing lymphocytes. Strong induction of IL-10-producing cells and T(reg) was observed when using N protein-pulsed MoDCs, suggesting an important role of MoDCs in induction of IL-10 and T(reg) by the N protein. Neutralization of IL-10 by addition of an anti-IL-10 antibody in the culture system resulted in marked reduction of PRRSV-induced T(reg) in the cultured PBMCs. Together, the data demonstrate the immunomodulatory properties of the PRRSV N protein and the linkage between IL-10 production and development of PRRSV-induced T(reg). Our results reveal an immunomodulatory function of the PRRSV N protein that may contribute to the unique immunological outcome observed following PRRSV infection.
authors.affiliation: Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand.|Interdisciplinary Program of Medical Microbiology, Graduate School, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Piya
authors.initials: P
authors.lastname: Wongyanin
authors.affiliation: Interdisciplinary Program of Medical Microbiology, Graduate School, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Supranee
authors.initials: S
authors.lastname: Buranapraditkul
authors.affiliation: Department of Pathobiology, University of Illinois at Urbana-Champaign, Urbana, IL 61802, USA.
authors.forename: Dongwan
authors.initials: D
authors.lastname: Yoo
authors.affiliation: Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Roongroje
authors.initials: R
authors.lastname: Thanawongnuwech
authors.affiliation: College of Veterinary Medicine, Iowa State University, Ames, IA 50011, USA.
authors.forename: James A
authors.initials: JA
authors.lastname: Roth
authors.affiliation: Faculty of Veterinary Science, Chulalongkorn University, Bangkok 10330, Thailand.
authors.forename: Sanipa
authors.initials: S
authors.lastname: Suradhat
mesh_terms: D000818:Animals; D003713:Dendritic Cells / Q000276:immunology / Q000821:virology; D016753:Interleukin-10 / Q000235:genetics / Q000276:immunology*; D008213:Lymphocyte Activation; D016676:Macrophages, Alveolar / Q000276:immunology / Q000821:virology; D019590:Nucleocapsid Proteins / Q000235:genetics / Q000276:immunology*; D019318:Porcine Reproductive and Respiratory Syndrome / Q000235:genetics / Q000276:immunology* / Q000821:virology; D019316:Porcine respiratory and reproductive syndrome virus / Q000235:genetics / Q000276:immunology* / Q000502:physiology; D013552:Swine; D050378:T-Lymphocytes, Regulatory / Q000276:immunology*; D015854:Up-Regulation
chemical_list: D019590:Nucleocapsid Proteins; D016753:Interleukin-10