RT Journal Article SR Electronic(1) A1 Wongyanin, Piya A1 Buranapraditkul, Supranee A1 Yoo, Dongwan A1 Thanawongnuwech, Roongroje A1 Roth, James A. A1 Suradhat, SanipaYR 2012 T1 Role of porcine reproductive and respiratory syndrome virus nucleocapsid protein in induction of interleukin-10 and regulatory T-lymphocytes (Treg) JF Journal of General Virology, VO 93 IS 6 SP 1236 OP 1246 DO https://doi.org/10.1099/vir.0.040287-0 PB Microbiology Society, SN 1465-2099, AB 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 (Treg) 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 Treg was observed when using N protein-pulsed MoDCs, suggesting an important role of MoDCs in induction of IL-10 and Treg 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 Treg 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 Treg. Our results reveal an immunomodulatory function of the PRRSV N protein that may contribute to the unique immunological outcome observed following PRRSV infection., UL https://www.microbiologyresearch.org/content/journal/jgv/10.1099/vir.0.040287-0