title: Porcine reproductive and respiratory syndrome (PRRS): an immune dysregulatory pandemic.
abstract: Porcine reproductive and respiratory disease syndrome (PRRS) is a viral pandemic that especially affects neonates within the "critical window" of immunological development. PRRS was recognized in 1987 and within a few years became pandemic causing an estimated yearly $600,000 economic loss in the USA with comparative losses in most other countries. The causative agent is a single-stranded, positive-sense enveloped arterivirus (PRRSV) that infects macrophages and plasmacytoid dendritic cells. Despite the discovery of PRRSV in 1991 and the publication of >2,000 articles, the control of PRRS is problematic. Despite the large volume of literature on this disease, the cellular and molecular mechanisms describing how PRRSV dysregulates the host immune system are poorly understood. We know that PRRSV suppresses innate immunity and causes abnormal B cell proliferation and repertoire development, often lymphopenia and thymic atrophy. The PRRSV genome is highly diverse, rapidly evolving but amenable to the generation of many mutants and chimeric viruses for experimental studies. PRRSV only replicates in swine which adds to the experimental difficulty since no inbred well-defined animal models are available. In this article, we summarize current knowledge and apply it toward developing a series of provocative and testable hypotheses to explain how PRRSV immunomodulates the porcine immune system with the goal of adding new perspectives on this disease.
authors: Department of Microbiology, Carver College of Medicine, University of Iowa, Iowa City, IA, USA, john-butler@uiowa.edu.
authors: J E
authors: JE
authors: Butler
authors: K M
authors: KM
authors: Lager
authors: William
authors: W
authors: Golde
authors: Kay S
authors: KS
authors: Faaberg
authors: Marek
authors: M
authors: Sinkora
authors: Crystal
authors: C
authors: Loving
authors: Y I
authors: YI
authors: Zhang
mesh_terms: D000818:Animals; D049109:Cell Proliferation; D003713:Dendritic Cells / Q000276:immunology / Q000473:pathology / Q000821:virology; D007113:Immunity, Innate; D008264:Macrophages / Q000276:immunology / Q000473:pathology / Q000821:virology; D058873:Pandemics; D010950:Plasma Cells / Q000276:immunology / Q000473:pathology / Q000821:virology; D019318:Porcine Reproductive and Respiratory Syndrome / Q000453:epidemiology / Q000276:immunology* / Q000473:pathology; D019316:Porcine respiratory and reproductive syndrome virus / Q000276:immunology*; D011173:Portraits as Topic; D013552:Swine