title: Interplay between interferon-mediated innate immunity and porcine reproductive and respiratory syndrome virus.
abstract: Innate immunity is the first line of defense against viral infection, and in turn, viruses have evolved to evade host immune surveillance. As a result, viruses may persist in host and develop chronic infections. Type I interferons (IFN-α/β) are among the most potent antiviral cytokines triggered by viral infections. Porcine reproductive and respiratory syndrome (PRRS) is a disease of pigs that is characterized by negligible induction of type I IFNs and viral persistence for an extended period. For IFN production, RIG-I/MDA5 and JAK-STAT pathways are two major signaling pathways, and recent studies indicate that PRRS virus is armed to modulate type I IFN responses during infection. This review describes the viral strategies for modulation of type I IFN responses. At least three non-structural proteins (Nsp1, Nsp2, and Nsp11) and a structural protein (N nucleocapsid protein) have been identified and characterized to play roles in the IFN suppression and NF-κB pathways. Nsp's are early proteins while N is a late protein, suggesting that additional signaling pathways may be involved in addition to the IFN pathway. The understanding of molecular bases for virus-mediated modulation of host innate immune signaling will help us design new generation vaccines and control PRRS.
authors.affiliation: Department of Pathobiology, University of Illinois at Urbana-Champaign, Urbana, IL 61802, USA.
authors.forename: Yan
authors.initials: Y
authors.lastname: Sun
authors.forename: Mingyuan
authors.initials: M
authors.lastname: Han
authors.forename: Chiyong
authors.initials: C
authors.lastname: Kim
authors.forename: Jay G
authors.initials: JG
authors.lastname: Calvert
authors.forename: Dongwan
authors.initials: D
authors.lastname: Yoo
mesh_terms: D000818:Animals; D054884:Host-Pathogen Interactions; D057131:Immune Evasion; D007108:Immune Tolerance; D007113:Immunity, Innate; D007372:Interferons / Q000276:immunology*; D019318:Porcine Reproductive and Respiratory Syndrome / Q000276:immunology / Q000821:virology*; D019316:Porcine respiratory and reproductive syndrome virus / Q000276:immunology / Q000472:pathogenicity*; D013552:Swine; D014764:Viral Proteins / Q000378:metabolism; D037521:Virulence Factors / Q000378:metabolism
chemical_list: D014764:Viral Proteins; D037521:Virulence Factors; D007372:Interferons