title: Porcine reproductive and respiratory syndrome virus induces pronounced immune modulatory responses at mucosal tissues in the parental vaccine strain VR2332 infected pigs.
abstract: Porcine reproductive and respiratory syndrome (PRRS) is a chronic viral disease of pigs caused by PRRS virus (PRRSV). The PRRSV VR2332 is the prototype North American parental strain commonly used in the preparation of vaccines. Goal of this study was to understand missing information on VR2332 induced immune modulation at the lungs and lymphoid tissues, the sites of PRRSV replication. Pigs were infected intranasally and samples collected at post-infection day (PID) 15, 30, and 60. Microscopically, lungs had moderate interstitial pneumonia, and the virus was detected in all the tested tissues. Peak antibody response and the cytokine IFN-γ secretion were detected at PID 30, with increased TGF-β until PID 60. Population of CD8(+), CD4(+), and CD4(+)CD8(+)T cells, Natural killer (NK) cells, and γδ T cells in the lungs and lymphoid tissues were significantly modulated favoring PRRSV persistence. The NK cell-mediated cytotoxicity was significantly reduced in infected pigs. In addition, increased population of immunosuppressive T-regulatory cells (Tregs) and associated cytokines were also observed in VR2332 strain infected pigs.
authors.affiliation: Food Animal Health Research Program, Ohio Agricultural Research and Development Center, Department of Veterinary Preventive Medicine, The Ohio State University, 1680 Madison Avenue, Wooster, OH 44691, USA.
authors.forename: Cordelia
authors.initials: C
authors.lastname: Manickam
authors.forename: Varun
authors.initials: V
authors.lastname: Dwivedi
authors.forename: Ruthi
authors.initials: R
authors.lastname: Patterson
authors.forename: Tracey
authors.initials: T
authors.lastname: Papenfuss
authors.forename: Gourapura J
authors.initials: GJ
authors.lastname: Renukaradhya
mesh_terms: D000281:Administration, Intranasal; D000818:Animals; D000914:Antibodies, Viral / Q000096:biosynthesis / Q000276:immunology; D002460:Cell Line; D002522:Chlorocebus aethiops; D016207:Cytokines / Q000276:immunology; D003602:Cytotoxicity, Immunologic; D007371:Interferon-gamma / Q000276:immunology; D007694:Killer Cells, Natural / Q000276:immunology; D008168:Lung / Q000276:immunology / Q000473:pathology / Q000821:virology; D008221:Lymphoid Tissue / Q000276:immunology / Q000821:virology; D009092:Mucous Membrane / Q000276:immunology* / Q000821:virology*; D019318:Porcine Reproductive and Respiratory Syndrome / Q000276:immunology* / Q000473:pathology / Q000821:virology; D019316:Porcine respiratory and reproductive syndrome virus / Q000276:immunology*; D034421:Sus scrofa; D013552:Swine; D016212:Transforming Growth Factor beta / Q000276:immunology; D014613:Vaccines, Attenuated / Q000276:immunology; D019562:Viral Load; D014765:Viral Vaccines / Q000276:immunology
chemical_list: D000914:Antibodies, Viral; D016207:Cytokines; D016212:Transforming Growth Factor beta; D014613:Vaccines, Attenuated; D014765:Viral Vaccines; D007371:Interferon-gamma