| duplex nested reverse transcriptase polymerase chain reaction for simultaneous detection of type 2 porcine reproductive and respiratory syndrome virus and porcine circovirus type 2 from tissue samples. | there are high levels of co-incidence of porcine reproductive and respiratory syndrome virus (prrsv) and porcine circovirus type 2 (pcv2) in porcine tissue. this study established a duplex nested reverse transcriptase polymerase chain reaction (rt-pcr) method that targets the genomic rna of type 2 prrsv and the mrna of pcv2 in infected tissues. the method amplified discriminative bands of 347 bp and 265 bp specific for type 2 prrsv and pcv2, respectively. the limits of detection of the duplex ne ... | 2017 | 27515271 |
| a two-year follow-up study of the pcv2 status of a danish pig herd that was initially assumed to be pcv2-free. | a longitudinal study was carried out to investigate whether a herd that had previously tested negative for porcine circovirus type 2 (pcv2) by polymerase chain reaction (pcr) was free of pcv2 or whether the negative profiles indicate that the level of pcv2 varies over time. | 2015 | 28405414 |
| the role of orf3 accessory protein in replication of cell-adapted porcine epidemic diarrhea virus (pedv). | the orf3 accessory protein has been shown to impede reverse genetics of cell-culture-adapted porcine epidemic diarrhea virus (pedv). its absence or truncated variants are also associated with viral attenuation in vivo. here, three orf3 variants (orf3np12, orf3np14 and orf3rb14) and their truncated counterparts were investigated for their regulatory role in recovery of cell-adapted pedv in vitro. we demonstrate that orf3np12, but not the truncated form, can inhibit recovery of reverse-genetics-de ... | 2017 | 28474223 |
| rt-pcr detection of porcine reproductive and respiratory syndrome virus based on the orf5 gene in mainland china, 2012-2015. | between january 2012 and december 2015, 13,567 clinical samples were collected from healthy pigs and pigs with a history of respiratory symptoms and/or reproductive disorders in 29 provinces of mainland china to detect porcine reproductive and respiratory syndrome virus (prrsv). from these samples, 7490 were prrsv-positive (average value, 55.21%). the annual prrsv detection rate from 2012 to 2015 for each year is 45.67%, 55.99%, 56.91%, and 59.07%, respectively. phylogenetic analyses revealed th ... | 2017 | 28854798 |
| analysis of genetic variation of two nadc30-like strains of porcine reproductive and respiratory syndrome virus in china. | nadc30-like strains of porcine reproductive and respiratory syndrome virus first appeared in chinese swine herds in 2012. | 2017 | 28839509 |
| pathogenic characterization of european genotype porcine reproductive and respiratory syndrome virus recently isolated in mainland china. | porcine reproductive and respiratory syndrome virus (prrsv) is an important pathogen in pig that causes tremendous economic loss in the global swine industry. prrsv is divided into the european and north american genotypes, with virulence ranging from apathogenic-moderately virulent to highly pathogenic. the emergence of new highly virulent type 1 strains and coexistence of the two genotypes complicate the differential diagnosis, disease prevention, and control of prrsv. although the emergence o ... | 2017 | 28839508 |
| nadc30-like porcine reproductive and respiratory syndrome in china. | nadc30-like porcine reproductive and respiratory syndrome virus (prrsv) has widely spread in china and become locally dominant virus strain in some provinces. although they are not pathogenic as highly pathogenic prrsv (hp-rrrsv) that outbreaks since 2006, nadc30-like prrsvs distinguished themselves by high incidence of recombination with other virus strains which lead to change of virulence. the outbreaks of nadc30-like prrsv in the vaccinated pig herds suggested that current commercial prrsv v ... | 2017 | 28839505 |
| deep sequencing details the cross-over map of chimeric genes in two porcine reproductive and respiratory syndrome virus infectious clones. | recombination is an important contributor to the genetic diversity of most viruses. a reverse genetics system using green fluorescence protein (gfp)- and enhanced gfp (egfp)-expressing infectious clones was developed to study the requirements for recombination. however, it is still unclear what types of cross-over events occurred to produce the viable offspring. | 2017 | 28839504 |
| emergence and reemergence of porcine reproductive and respiratory syndrome virus (prrsv). | | 2017 | 28839503 |
| orf1a of highly pathogenic prrs attenuated vaccine virus plays a key role in neutralizing antibody induction in piglets and virus neutralization in vitro. | currently, porcine reproductive and respiratory syndrome virus (prrsv) is one of the most economically important viral pathogens in swine in most countries, especially china. two prrsv attenuated live vaccine strains (hun4-f112 and ch-1r) are currently widely used in china. our previous study showed that hun4-f112, but not ch-1r, induced high anti-nucleocapsid (n) antibody and neutralizing antibody (na) titers. additionally, sera from hun4-f112 inoculated pigs induced low cross neutralization of ... | 2017 | 28830563 |
| rab11a is required for porcine reproductive and respiratory syndrome virus induced autophagy to promote viral replication. | porcine reproductive and respiratory syndrome virus (prrsv) is the leading virus known to cause massive economic loss in pig industry worldwide. in our previous study, transcriptional profiling of prrsv-infected lung tissue of tongcheng and landrane pigs, which have highly pathogenic prrsv (hp-prrsv) susceptibility differences, showed differential expression of rab11a. the small gtpase rab11a regulates intracellular membrane trafficking events involved in autophagy. however, the involvement of t ... | 2017 | 28822762 |
| a conjugate protein containing hiv tat, isg20, and a prrsv polymerase binding inhibits prrsv replication and may be a novel therapeutic platform. | porcine reproductive and respiratory syndrome (prrs), which is caused by porcine reproductive and respiratory syndrome virus (prrsv) infection, has caused substantial economic losses for the global swine industry. to date, there are limited commercially available measures to control the spread of prrsv. the available vaccines are unstable and there is no anti-prrsv therapeutic available. therefore, this study designed a novel recombinant antiviral protein that included a novel polypeptide that b ... | 2017 | 28818749 |
| identification and characterization of small molecule inhibitors of porcine reproductive and respiratory syndrome virus. | porcine reproductive and respiratory syndrome virus (prrsv) is the etiological agent of prrs, an economically significant disease of swine worldwide. prrsv is poorly controlled by the currently available vaccines, and alternative control strategies are needed to help prevent the continual circulation of the virus. previously, we developed a synthetic route for the natural compound atractylodinol and demonstrated anti-prrsv activity in vitro. however, the synthetic route was inefficient and the y ... | 2017 | 28811186 |
| the complex co-translational processing of glycoprotein gp5 of type 1 porcine reproductive and respiratory syndrome virus. | gp5 and m, the major membrane proteins of porcine reproductive and respiratory syndrome virus (prrsv), are the driving force for virus budding and a target for antibodies. we studied co-translational processing of gp5 from an european prrsv-1 strain. using mass spectrometry, we show that in virus particles of a lelystad variant, the signal peptide of gp5 was absent due to cleavage between glycine-34 and asparagine-35. this cleavage site removes an epitope for a neutralizing monoclonal antibody, ... | 2017 | 28807563 |
| porcine 2', 5'-oligoadenylate synthetase 2 inhibits porcine reproductive and respiratory syndrome virus replication in vitro. | porcine reproductive and respiratory syndrome virus (prrsv) is acknowledged a fulminating infectious pathogen affecting the pig farming industry, and current vaccines and drugs could hardly inhibit this virus. the 2', 5'-oligoadenylate synthetase (oass) have antiviral activities, but the role(s) played by porcine oas2 in protection against prrsv infection are unknown. here we found that endogenous expression of the porcine oas2 gene could be promoted by interferon (ifn)-beta or prrsv infection i ... | 2017 | 28804020 |
| in vitro and in vivo studies of deglycosylated chimeric porcine reproductive and respiratory syndrome virus as a vaccine candidate and its realistic revenue impact at commercial pig production level. | porcine reproductive and respiratory syndrome virus (prrsv) causes major economic losses in the swine industry worldwide. vaccination is the most effective method to control the disease. in a previous study, a chimeric prrsv named as k418 which had a genome composed of orf 1 from the fl12 strain and orf 2-7 from the korean representative lmy strain was created. we constructed k418dm, k418 with deglycosylated glycoprotein 5 (gp5), to improve its humoral immunity. in the follow-up on in vivo and i ... | 2017 | 28802752 |
| role of transcription regulatory sequence in regulation of gene expression and replication of porcine reproductive and respiratory syndrome virus. | in order to gain insight into the role of the transcription regulatory sequences (trss) in the regulation of gene expression and replication of porcine reproductive and respiratory syndrome virus (prrsv), the enhanced green fluorescent protein (egfp) gene, under the control of the different structural gene trss, was inserted between the n gene and 3'-utr of the prrsv genome and egfp expression was analyzed for each trs. trss of all the studied structural genes of prrsv positively modulated egfp ... | 2017 | 28797297 |
| reconciling individual and population levels of porcine reproductive and respiratory syndrome virus evolution. | | 2017 | 28795353 |
| dendritic cell-targeted porcine reproductive and respiratory syndrome virus (prrsv) antigens adjuvanted with polyinosinic-polycytidylic acid (poly (i:c)) induced non-protective immune responses against heterologous type 2 prrsv challenge in pigs. | porcine reproductive and respiratory syndrome (prrs) is an economically important swine viral disease worldwide. current modified live-attenuated vaccines are ineffective against heterologous strains of prrs virus (prrsv) circulating in the field. in this study, we evaluated three dendritic cell (dc)-targeted vaccine candidates for their protective efficacy against heterologous prrsv challenge. ectodomain regions of dna-shuffled structural proteins gp3, gp4, gp5 and m of prrsv were fused togethe ... | 2017 | 28778318 |
| a multiplex rt-pcr assay to detect and discriminate porcine reproductive and respiratory syndrome viruses in clinical specimens. | outbreaks of highly pathogenic porcine reproductive and respiratory syndrome virus (hp-prrsv) have led to large economic losses in china. the attenuated vaccine (hp-prrsv jxa1-r) was used to control hp-prrsv. however, in recent years, co-infection with classical prrsv (c-prrsv), hp-prrsv, and/or hp-prrsv jxa1-r has been increasing in china, resulting in a significant impact on prrsv diagnostics and management. to facilitate rapid discrimination of hp-prrsv jxa1-r from hp-prrsv and c-prrsv, a mul ... | 2017 | 28763016 |
| genetic diversity in envelope genes of contemporary u.s. porcine reproductive and respiratory syndrome virus strains influences viral antigenicity. | porcine reproductive and respiratory syndrome (prrs) is one of the most economically important diseases in swine caused by porcine reproductive and respiratory syndrome virus (prrsv). genome sequences of sixty-six prrsv strains were obtained using metagenomic sequencing of serum samples collected in the u.s. in 2014 to explore contemporary genetic diversity. phylogenetic analysis of the genes encoding the envelope proteins identified four to eight distinct lineages with >87% intraclade identity. ... | 2017 | 28759862 |
| b cell tetramer development for veterinary vaccinology. | immunological memory is elicited after either vaccination or natural exposure to a pathogen and is essential for protection against re-exposure. despite its critical importance, the ability to interrogate the veterinary animal memory immune response has long been hindered by a paucity of tools to assess immunological memory. as a result, the evaluation and analysis of protective immune responses that predict immune protection in food and fiber animals and facilitate vaccine development are obstr ... | 2017 | 28759334 |
| porcine interferon stimulated gene 12a restricts porcine reproductive and respiratory syndrome virus replication in marc-145 cells. | porcine reproductive and respiratory syndrome virus (prrsv) causes severe losses in the global pig industry. in the present study, we investigated the molecular characterization of porcine interferon stimulated gene 12a (isg12a) and confirmed its anti-prrsv ability for the first time. we found that porcine isg12a was localized in mitochondria and significantly decreased the number of cells in g2/s phase. porcine isg12a mrna was up-regulated in cells/tissues of tongcheng (tc) pigs and large white ... | 2017 | 28757561 |
| efficacy evaluation of three modified-live virus vaccines against a strain of porcine reproductive and respiratory syndrome virus nadc30-like. | porcine reproductive and respiratory syndrome reproductive virus is a devastating pathogen causing tremendous economic losses to swine production worldwide. emergence of novel and variant prrsv strains always leads to variable protection efficacy of modified-live virus (mlv) vaccines. prevalence of prrsv nadc30-like recently emerging in china has brought about clinical outbreaks of the disease. in the present study, the pathogenicity of a nadc30-like strain chsx1401 for piglets was analyzed, and ... | 2017 | 28757009 |
| epidemiological investigations of the introduction of porcine reproductive and respiratory syndrome virus in chile, 2013-2015. | porcine reproductive and respiratory syndrome (prrs) is endemic in most pork producing countries. in chile, eradication of prrs virus (prrsv) was successfully achieved in 2009 as a result of the combined efforts of producers and the animal health authorities. in october 2013, after several years without detecting prrsv under surveillance activities, suspected cases were confirmed on a commercial swine farm. here, we describe the prrs epidemic in chile between october 2013 and april 2015, and we ... | 2017 | 28742879 |
| genetic characterization of 11 porcine reproductive and respiratory syndrome virus isolates in south china from 2014 to 2015. | porcine reproductive and respiratory syndrome (prrs) has leaded to an enormous loss per year to the swine industry, its etiology porcine reproductive and respiratory syndrome virus (prrsv) is a highly mutated virus in pigs. to fully understand the genetic characteristics of prrsv genome in south china, this study collected the lung samples infected with prrsv in guangdong and hainan province from 2014 to 2015 and tried to isolate the prrsv. finally, the complete genomes of isolated strains were ... | 2017 | 28738888 |
| comparative analysis of signature genes in prrsv-infected porcine monocyte-derived cells to different stimuli. | monocyte-derived dcs (mdcs) are major target cells in porcine reproductive and respiratory syndrome virus (prrsv) pathogenesis; however, the plasticity of mdcs in response to activation stimuli and prrsv infection remains unstudied. in this study, we polarized mdcs, and applied genome-wide transcriptomic analysis and predicted protein-protein interaction networks to compare signature genes involved in mdcs activation and response to prrsv infection. porcine mdcs were polarized with mediators for ... | 2017 | 28727780 |
| porcine reproductive and respiratory syndrome virus (prrsv) in pig meat. | porcine reproductive and respiratory syndrome, caused by the porcine reproductive and respiratory syndrome virus (prrsv), is an economically important disease in the swine industry. previous studies demonstrated the presence of the virus in pig meat and its transmissibility by oral consumption. this study further analyzed the infectivity of prrsv in commercial pig meat. fresh bottom meat pieces (n = 1500) randomly selected over a period of 2 y from a pork ham boning plant located in quebec, cana ... | 2017 | 28725105 |
| cholesterol 25-hydroxylase inhibits porcine reproductive and respiratory syndrome virus replication through enzyme activity dependent and independent mechanisms. | cholesterol 25-hydroxylase (ch25h) has recently been identified as a host restriction factor that exerts antiviral effects by catalyzing the production of 25-hydroxycholesterol (25hc). ch25h can be rapidly induced upon infection with some viruses. porcine reproductive and respiratory syndrome virus (prrsv), an arterivirus, has ranked among the most important swine pathogens since it was discovered in the late 1980s. in this study, we found that prrsv infection significantly downregulated the exp ... | 2017 | 28724759 |
| optisampletm: open web-based application to optimize sampling strategies for active surveillance activities at the herd level illustrated using porcine respiratory reproductive syndrome (prrs). | porcine reproductive and respiratory syndrome virus (prrsv) infection causes a devastating economic impact to the swine industry. active surveillance is routinely conducted in many swine herds to demonstrate freedom from prrsv infection. the design of efficient active surveillance sampling schemes is challenging because optimum surveillance strategies may differ depending on infection status, herd structure, management, or resources for conducting sampling. here, we present an open web-based app ... | 2017 | 28719658 |
| effect of immunologic solutions on sows and gilts on time to stability, and production losses in breeding herds infected with 1-7-4 prrsv. | porcine reproductive and respiratory syndrome virus (prrsv) is an economically significant swine pathogen causing production losses in the global swine industry. clinical impact depends on many factors including the virus itself. one method to sub-type prrsv is using restriction fragment length polymorphism (rflp). the rflp pattern 1-7-4 emerged within the united states swine industry in 2014 and has become prevalent since then. this was a field study that prospectively followed 1-7-4-infected b ... | 2017 | 28716191 |
| a recombinant type 2 porcine reproductive and respiratory syndrome virus between nadc30-like and a mlv-like: genetic characterization and pathogenicity for piglets. | porcine reproductive and respiratory syndrome virus (prrsv) is an economically important pathogen for swine industry worldwide. the recombination occurring among prrsv strains has been recognized as one of important molecular mechanisms for the evolution of prrsv. current prevalence of prrsv nadc30-like causing clinical disease outbreaks is highly concerned in china. in the present study, the genetic characterization of a recombinant type 2 prrsv (designated tjnh1501) was analyzed and its pathog ... | 2017 | 28713014 |
| transcriptome differences in porcine alveolar macrophages from tongcheng and large white pigs in response to highly pathogenic porcine reproductive and respiratory syndrome virus (prrsv) infection. | porcine reproductive and respiratory syndrome virus (prrsv) is a single-stranded positive-sense rna virus that can cause devastating reproductive failure and respiratory tract lesions, which has led to serious damage to the swine industry worldwide. our previous studies have indicated that tongcheng (tc) pigs, a chinese local breed, have stronger resistance or tolerance to prrsv infection than large white (lw) pigs. this study aims to investigate their host transcriptome differences in porcine a ... | 2017 | 28704922 |
| the middle half genome of interferon-inducing porcine reproductive and respiratory syndrome virus strain a2mc2 is essential for interferon induction. | porcine reproductive and respiratory syndrome virus (prrsv) is known to antagonize the innate immune response. an atypical prrsv strain a2mc2 is capable of inducing synthesis of type i interferons (ifns) in cultured cells. here, we show that the middle half of the a2mc2 genome is needed for triggering the ifn synthesis. first, a cdna infectious clone of this atypical strain was constructed as a dna-launched version. virus recovery was achieved from the infectious clone and the recovered virus, r ... | 2017 | 28699875 |
| genome-wide analysis of long noncoding rna profiling in prrsv-infected pam cells by rna sequencing. | porcine reproductive and respiratory syndrome (prrs) is a major threat to the global swine industry and causes tremendous economic losses. its causative agent, porcine reproductive and respiratory syndrome virus (prrsv), primarily infects immune cells, such as porcine alveolar macrophages and dendritic cells. prrsv infection results in immune suppression, antibody-dependent enhancement, and persistent infection. highly pathogenic strains in china cause high fever and severe inflammatory response ... | 2017 | 28694521 |
| interleukin-2 enhancer binding factor 2 interacts with the nsp9 or nsp2 of porcine reproductive and respiratory syndrome virus and exerts negatively regulatory effect on the viral replication. | porcine reproductive and respiratory syndrome virus (prrsv) causes reproductive failures in sows and respiratory diseases in growing pigs, resulting in huge economic loss for the pig production worldwide. the nonstructural protein 9 (nsp9) and nonstructural protein 2 (nsp2) of prrsv are known to play important roles in viral replication. cellular interleukin-2 enhancer binding factor 2 (ilf2) participates in many cellular pathways and involves in life cycle of some viruses. in the present study, ... | 2017 | 28693575 |
| relative contribution of porcine reproductive and respiratory syndrome virus open reading frames 2-4 to the induction of protective immunity. | the minor glycoproteins (gps) of prrsv, gp2, gp3, and gp4, form a heterotrimer that is required for viral infectivity, presumably due to its interaction with the key cellular receptor cd163. these 3gps are encoded by open reading frames (orfs) 2a, 3 and 4 (herein referred to as orfs 2-4), respectively. the goal of this study was to investigate the immunogenicity of the prrsv-2 minor gps. through the use of reverse genetics, a chimeric virus (designated sdfl24) was constructed by replacing orfs 2 ... | 2017 | 28689650 |
| the development of a sensitive droplet digital pcr for quantitative detection of porcine reproductive and respiratory syndrome virus. | porcine reproductive and respiratory syndrome (prrs) is an infectious disease, resulting in important economic losses in pig farming. prompt detection of prrs virus (prrsv) in the field samples is important for effective prrs control. droplet digital pcr (ddpcr) is a novel pcr technology, which offers good precision and direct quantification without using calibration curves. in this study, we established a ddpcr system for the sensitive and accurate quantification of prrsv. specificity of the as ... | 2017 | 28669806 |
| amplification and selection of prrsv-activated vdj repertoires in pigs secreting distinct neutralizing antiboidies. | neutralizing antibodies (nabs) play an important role in protective immunity against porcine reproductive and respiratory syndrome virus (prrsv) infection. however, the characterization of prrsv nab repertoires is rarely investigated. in this study, we developed a swine vdj amplification method and selection criteria for the characterization of prrsv-activated vdj repertoires. according to clonal expansion theory, two separated aliquots of lymph nodes from pigs producing different prrsv nabs wer ... | 2017 | 28669387 |
| novel approaches for spatial and molecular surveillance of porcine reproductive and respiratory syndrome virus (prrsv) in the united states. | the us swine industry has been impaired over the last 25 years by the far-reaching financial losses caused by the porcine reproductive and respiratory syndrome (prrs). here, we explored the relations between the spatial risk of prrs outbreaks and its phylodynamic history in the u.s during 1998-2016 using orf5 sequences collected from swine farms in the midwest region. we used maximum entropy and bayesian phylodynamic models to generate risk maps for prrs outbreaks and reconstructed the evolution ... | 2017 | 28659596 |
| the nucleocapsid protein and nonstructural protein 10 of highly pathogenic porcine reproductive and respiratory syndrome virus enhance cd83 production via nf-κb and sp1 signaling pathways. | porcine reproductive and respiratory syndrome, caused by porcine reproductive and respiratory syndrome virus (prrsv), is a panzootic disease that is one of the most economically costly diseases to the swine industry. a key aspect of prrsv virulence is that the virus suppresses the innate immune response and induces persistent infection, although the underlying mechanisms are not well understood. the dendritic cell (dc) marker cd83 belongs to the immunoglobulin superfamily and is associated with ... | 2017 | 28659471 |
| antiviral strategies against prrsv infection. | prrsv (porcine reproductive and respiratory syndrome virus) is a major economically significant pathogen that has adversely impacted the global swine industry for almost 30 years. currently prrsv is estimated to cause losses of almost us$600 million per year in the usa. except for new mutants that continually emerge during prrsv outbreaks, our understanding of the virology, origin, and evolution of prrsv and the host's immune response are largely inadequate. such limited knowledge impedes develo ... | 2017 | 28652073 |
| cellular dead-box rna helicase 18 (ddx18) promotes the prrsv replication via interaction with virus nsp2 and nsp10. | porcine reproductive and respiratory syndrome virus (prrsv) is an aetiological agent that can lead to reproductive failure and respiratory diseases of pigs. the replication and pathogenesis of prrsv, although poorly understood, has been associated with the host factors. ddx18 is a member of dead-box rna helicases (ddxs) family which were proved to participate in viral replication. previously, we found the ddx18 interacts with both nsp2 and nsp10 of prrsv by co-immunoprecipitation (co-ip). in the ... | 2017 | 28648849 |
| vaccination against porcine reproductive and respiratory syndrome virus (prrsv) reduces the magnitude and duration of viremia following challenge with a virulent heterologous field strain. | forty prrs-negative, three week-old weaned pigs were randomized into two groups in separate rooms and inoculated with a modified live prrs vaccine (fostera(®) prrs) or control (pbs). four weeks after vaccination pigs were rehoused in a single room and challenged intranasally and intramuscularly with virulent prrsv strain nadc20. timed serum samples were collected and titrated for prrs virus and anti-prrs virus antibodies. the study concluded when ≥80% of the pigs in the control group were determ ... | 2017 | 28622868 |
| reduction of infection by inhibiting mtor pathway is associated with reversed repression of type i interferon by porcine reproductive and respiratory syndrome virus. | type i interferons (ifns) are critical in animal antiviral regulation. ifn-mediated signalling regulates hundreds of genes that are directly associated with antiviral, immune and other physiological responses. the signalling pathway mediated by mechanistic target of rapamycin (mtor), a serine/threonine kinase regulated by ifns, is key in regulation of cellular metabolism and was recently implicated in host antiviral responses. however, little is known about how animal type i ifn signalling coord ... | 2017 | 28613152 |
| cnv analysis of host responses to porcine reproductive and respiratory syndrome virus infection. | porcine reproductive and respiratory syndrome (prrs) is a devastating disease with a significant impact on the swine industry causing major economic losses. the objective of this study is to examine copy number variations (cnvs) associated with the group-specific host responses to prrs virus infection. we performed a genome-wide cnv analysis using 660 animals genotyped with on the porcine snp60 beadchip and discovered 7097 cnvs and 271 cnv regions (cnvrs). for this study, we used two established ... | 2017 | 28611852 |
| mechanisms of adaptive immunity to porcine reproductive and respiratory syndrome virus. | the adaptive immune response is necessary for the development of protective immunity against infectious diseases. porcine reproductive and respiratory syndrome virus (prrsv), a genetically heterogeneous and rapidly evolving rna virus, is the most burdensome pathogen of swine health and wellbeing worldwide. viral infection induces antigen-specific immunity that ultimately clears the infection. however, the resulting immune memory, induced by virulent or attenuated vaccine viruses, is inconsistent ... | 2017 | 28608816 |
| cost of porcine reproductive and respiratory syndrome virus at individual farm level - an economic disease model. | porcine reproductive and respiratory syndrome (prrs) is reported to be among the diseases with the highest economic impact in modern pig production worldwide. yet, the economic impact of the disease at farm level is not well understood as, especially in endemically infected pig herds, losses are often not obvious. it is therefore difficult for farmers and veterinarians to appraise whether control measures such as virus elimination or vaccination will be economically beneficial for their farm. th ... | 2017 | 28606362 |
| development of a stochastic agent-based model to evaluate surveillance strategies for detection of emergent porcine reproductive and respiratory syndrome strains. | the objective of the current study was to develop a stochastic agent-based model using empirical data from ontario (canada) swine sites in order to evaluate different surveillance strategies for detection of emerging porcine reproductive and respiratory syndrome virus (prrsv) strains at the regional level. four strategies were evaluated, including (i) random sampling of fixed numbers of swine sites monthly; (ii) risk-based sampling of fixed numbers, specifically of breeding sites (high-consequen ... | 2017 | 28606148 |
| prediction and in vitro verification of potential ctl epitopes conserved among prrsv-2 strains. | porcine reproductive and respiratory syndrome virus (prrsv) is the causative agent of one of the most important porcine diseases with a high impact on animal health, welfare, and production economy. prrsv exhibits a multitude of immunoevasive strategies that, in combination with a very high mutation rate, has hampered the development of safe and broadly protective vaccines. aiming at a vaccine inducing an effective cytotoxic t cell response, a bioinformatics approach was taken to identify conser ... | 2017 | 28589207 |
| complete genome sequence of a recombinant porcine reproductive and respiratory syndrome virus strain from two genotype 1 modified live virus vaccine strains. | this paper provides information on the complete genome sequence of a porcine reproductive and respiratory syndrome virus (prrsv) strain isolated on a french pig farm which was identified as a recombinant strain from two commercial modified live virus vaccine strains of genotype 1 (vp-046bis and dv strains). | 2017 | 28572326 |
| pathogenicity of three genetically diverse strains of prrsv type 1 in specific pathogen free pigs. | studies from eastern european countries proved that porcine reproductive and respiratory syndrome virus type 1 (prrsv-1) harbours high genetic diversity and that genetically divergent subtypes 2-4 circulate in this area. in the present study, we compared the pathogenicity of two different prrsv-1 subtype 2 strains and a strain representing prrsv-1 subtype 1. four groups of 8-week-old specific pathogen free pigs were either infected with subtype 2 strain ili6, subtype 2 strain or bor59, subtype 1 ... | 2017 | 28554869 |
| structural analysis of porcine reproductive and respiratory syndrome virus non-structural protein 7α (nsp7α) and identification of its interaction with nsp9. | non-structural protein 7 (nsp7), which can be further cleaved into nsp7α and nsp7β, is one of the most conserved proteins of porcine reproductive and respiratory syndrome virus (prrsv). nsp7 plays a role in provoking the humoral immune system in prrsv-infected swine, but its structure and function are still not fully understood. here, we analyzed the expression of nsp7, nsp7α, and nsp7β in prrsv-infected marc-145 cells. the solution structure of nsp7α was determined by using nuclear magnetic res ... | 2017 | 28553277 |
| evaluation of porcine reproductive and respiratory syndrome stabilization protocols in 23 french farrow-to-finish farms located in a high-density swine area. | porcine reproductive and respiratory syndrome virus (prrsv) is responsible for reproductive disorders in sows and respiratory problems in pigs, and has a major economic impact. controlling prrsv is therefore a priority for the swine industry. stabilization of a herd, defined as the production of prrsv-negative pigs at weaning from seropositive sows, is a common method of control, and different protocols have been described in the literature to achieve this stabilization. | 2017 | 28546868 |
| oral fluid versus blood sampling in group-housed sows and finishing pigs: feasibility and performance of antibody detection for porcine reproductive and respiratory syndrome virus (prrsv). | the feasibility of using individual and pen-based oral fluid samples to detect prrsv antibodies in growing-finishing pigs and group-housed sows was investigated. the diagnostic performances of a commercial oral fluid elisa (of-elisa) and a serum elisa (ser-elisa) performed on individual or pooled samples from 5 or 10 pigs and sows was evaluated. the performance of the of-elisa was also assessed for pen-based oral fluids. eight hundred and thirty-four pigs and 1598 sows from 42 prrsv-infected and ... | 2017 | 28532802 |
| preparation for emergence of an eastern european porcine reproductive and respiratory syndrome virus (prrsv) strain in western europe: immunization with modified live virus vaccines or a field strain confers partial protection. | the porcine reproductive and respiratory syndrome virus (prrsv) causes huge economic losses for the swine industry worldwide. in the past several years, highly pathogenic strains that lead to even greater losses have emerged. for the western european swine industry, one threat is the possible introduction of eastern european prrsv strains (example lena genotype 1.3) which were shown to be more virulent than common western resident strains under experimental conditions. to prepare for the possibl ... | 2017 | 28532792 |
| recombination in jxa1-r vaccine and nadc30-like strain of porcine reproductive and respiratory syndrome viruses. | porcine reproductive and respiratory syndrome (prrs) is considered one of the most devastating swine diseases worldwide, resulting in immense economic losses. prrs virus (prrsv) has undergone rapid evolution since its first recognition in 1990s. in the present study, a prrsv strain named fjxs15 causing high morbidity and mortality was isolated from piglets and sows from a farm participating in vaccination in china. phylogenetic and molecular evolutionary analyses revealed that fjxs15 was highly ... | 2017 | 28532789 |
| molecular epidemiology of porcine reproductive and respiratory syndrome virus in central china since 2014: the prevalence of nadc30-like prrsvs. | porcine reproductive and respiratory syndrome (prrs), characterized by respiratory disorders in piglets and reproductive failure in sows, is still the great threat of swine industry. recently, emergence of the novel nadc30-like prrs viruses (prrsvs) has caused widespread outbreaks of prrs. to investigate the epidemic characteristics of prrsvs in central china since 2014, 6372 clinical serum samples were tested by elisa, 250 tissue samples were tested by rt-pcr, and among these, 30 orf5 and 17 ns ... | 2017 | 28512020 |
| genetic diversity and phylogenetic analysis of the orf5 gene of prrsv from central china. | to more fully understand the genetic diversity and molecular epidemiology of prevailing porcine reproductive and respiratory syndrome virus (prrsv) in henan province of china, 112 full-length orf5 gene sequences, originating from henan province between 2006 and 2015, were subjected to sequence variation and phylogenetic analysis. phylogenetic analysis revealed that all henan isolates belonged to the type 2 genotype and could be further divided into three subgroups. subgroup 1 and 2 viruses predo ... | 2017 | 28511131 |
| antigenic and biological characterization of orf2-6 variants at early times following prrsv infection. | genetic diversity of porcine reproductive and respiratory syndrome virus (prrsv) challenges efforts to develop effective and broadly acting vaccines. although genetic variation in prrsv has been extensively documented, the effects of this variation on virus phenotype are less well understood. in the present study, prrsv open reading frame (orf)2-6 variants predominant during the first six weeks following experimental infection were characterized for antigenic and replication phenotype. there was ... | 2017 | 28509878 |
| reverse genetics for porcine reproductive and respiratory syndrome virus. | porcine reproductive and respiratory syndrome (prrs) is a reemerging swine disease, and has become economically the most significant disease in pork production worldwide. the causative agent is prrs virus (prrsv), which is a member virus of the family arteriviridae. the prrsv genome is a single-stranded positive-sense rna and is infectious. two strategies in the prrsv reverse genetics system have been employed for reconstitution of progeny virus: rna transfection and dna transfection. the prrsv ... | 2017 | 28508212 |
| genetic diversity and evolutionary characteristics of type 2 porcine reproductive and respiratory syndrome virus in southeastern china from 2009 to 2014. | the objective of this study was to assess the genetic diversity of porcine reproductive and respiratory syndrome virus circulating in fujian province (southeastern china). based on 53 orf5 nucleotide sequences collected from nine sites, both highly pathogenic (sublineage 8.7) and lineage 1 strains were circulating in fujian in 2009-2014 along with lineages 3 and 5.1. notably, the lineage 1 strains were closely related to the nadc30 strain circulating in north america and were the predominant str ... | 2017 | 28500445 |
| regulation of inos-derived ros generation by hsp90 and cav-1 in porcine reproductive and respiratory syndrome virus-infected swine lung injury. | in the lungs, endothelial nitric oxide synthase (enos) is usually expressed in endothelial cells and inducible nitric oxide synthase (inos) is mainly expressed in alveolar macrophages and epithelial cells. both enos and inos are involved in lung inflammation. while they play several roles in lung inflammation formation and resolution, their expression and activity are also regulated by inflammatory factors. their expression relationship in virus infection-induced lung injury is not well addresse ... | 2017 | 28493081 |
| heparanase upregulation contributes to porcine reproductive and respiratory syndrome virus release. | porcine reproductive and respiratory syndrome virus (prrsv) continues to cause substantial economic losses to the pig industry worldwide. heparan sulfate (hs) is used by prrsv for initial attachment to target cells. however, the role of hs in the late phase of prrsv infection and the mechanism of virus release from host cells remain largely unknown. in this study, we showed that prrsv infection caused a decrease in hs expression and upregulated heparanase, the only known enzyme capable of degrad ... | 2017 | 28490587 |
| indian porcine reproductive and respiratory syndrome virus bears discontinuous deletion of 30 amino acids in nonstructural protein 2. | since its first outbreak in 2013, porcine reproductive and respiratory syndrome (prrs) has established as an enzootic disease in pig population of mizoram state, india. our previous studies based on phylogenetic analysis of orf5 and orf7 gene sequences revealed close relationship of indian prrsv with the highly pathogenic variant of prrsv (hp-prrsv) of chinese origin. despite the control measures, second major outbreak of the disease was recorded in aizawl district of mizoram in 2015. the object ... | 2016 | 28466041 |
| corrigendum: construction and immunogenicity of a recombinant swinepox virus expressing a multi-epitope peptide for porcine reproductive and respiratory syndrome virus. | | 2017 | 28430207 |
| use of multi-trait and random regression models to identify genetic variation in tolerance to porcine reproductive and respiratory syndrome virus. | a host can adopt two response strategies to infection: resistance (reduce pathogen load) and tolerance (minimize impact of infection on performance). both strategies may be under genetic control and could thus be targeted for genetic improvement. although there is evidence that supports a genetic basis for resistance to porcine reproductive and respiratory syndrome (prrs), it is not known whether pigs also differ genetically in tolerance. we determined to what extent pigs that have been shown to ... | 2017 | 28424056 |
| porcine reproductive and respiratory syndrome virus infection induces stress granule formation depending on protein kinase r-like endoplasmic reticulum kinase (perk) in marc-145 cells. | stress granules (sgs) are sites of mrna storage that are formed in response to various conditions of stress, including viral infections. porcine reproductive and respiratory syndrome virus (prrsv) is an arterivirus that has been devastating the swine industry worldwide since the late 1980s. in this study, we found that infection of prrsv strain wuh3 (genotype 2 prrsv) induced stable formation of robust sgs in marc-145 cells, as demonstrated by the recruitment of marker proteins of sgs, including ... | 2017 | 28421170 |
| effector mechanisms of humoral immunity to porcine reproductive and respiratory syndrome virus. | porcine reproductive and respiratory syndrome virus (prrsv) continues to afflict swine nearly 30 years after it was first discovered as the causative agent of "mystery swine disease". immunological tools of vaccination and exposure to virulent viruses have not succeeded in achieving control and prevention of prrsv. humoral immunity, mediated by antibodies, is a hallmark of anti-viral immunity, but little is known about the effector mechanisms of humoral immunity against prrsv. it is essential to ... | 2017 | 28413045 |
| structural insights into type i and type ii of nsp4 porcine reproductive and respiratory syndrome virus (nsp4 prrsv) by molecular dynamics simulations. | porcine reproductive and respiratory virus (prrsv) causes major economic concerns for the swine industry worldwide. we have performed molecular dynamics simulations (md) and principle component analysis (pca) to investigate the role of the catalytic triad and conformational dynamics of type i and type ii of nsp4 prrsv. the results showed that the rmsf of residues 136-142 near the active site of all models was highly flexible. moreover, we identified the effect of single structural mutations of t ... | 2017 | 28411461 |
| concurrent vaccination of boars with type 1 and type 2 porcine reproductive and respiratory syndrome virus (prrsv) reduces seminal shedding of type 1 and type 2 prrsv. | the objective of the present study was to determine the effect of concurrent vaccination of boars with type 1 and type 2 porcine reproductive and respiratory syndrome virus (prrsv) on seminal shedding of both genotypes. the boars tolerated well concurrent administration of 2 commercial prrsv vaccines, and no adverse reactions were observed. no interference in the humoral immune response (measured as the level of anti-prrsv antibodies) or the cell-mediated immune response (measured as the level o ... | 2017 | 28408778 |
| emergence of a virulent porcine reproductive and respiratory syndrome virus (prrsv) 1 strain in lower austria. | in spring 2015, an outbreak of porcine reproductive and respiratory syndrome (prrs) struck lower austria caused by a prrs virus (prrsv) strain spreading rapidly among both previously prrsv negative and vaccinated pig herds. this case report describes the first well-documented emergence of the prrsv strain responsible for this outbreak. | 2016 | 28405454 |
| modified-live prrsv subtype 1 vaccine unistrain(®) prrs provides a partial clinical and virological protection upon challenge with east european subtype 3 prrsv strain lena. | western european porcine reproductive and respiratory syndrome virus (prrsv) strains cause limited and mild clinical signs whereas more virulent strains are circulating in eastern europe. the emergence of such highly virulent strains in western europe might result in severe clinical problems and a financial disaster. in this context, the efficacy of the commercial modified-live prrsv subtype 1 vaccine unistrain(®) prrs was tested upon challenge with the east european subtype 3 prrsv strain lena. | 2016 | 28405438 |
| intranasal immunization of pigs with porcine reproductive and respiratory syndrome virus-like particles plus 2', 3'-cgamp vaccigrade™ adjuvant exacerbates viremia after virus challenge. | porcine reproductive and respiratory syndrome virus (prrsv) causes reproductive failure in pregnant sows and acute respiratory disease in young pigs. it is a leading infectious agent of swine respiratory complex, which has significant negative economic impact on the swine industry. commercial markets currently offer both live attenuated and killed vaccines; however, increasing controversy exists about their efficacy providing complete protection. virus-like particles (vlps) possess many desirabl ... | 2017 | 28403874 |
| genetic architecture of gene expression underlying variation in host response to porcine reproductive and respiratory syndrome virus infection. | it has been shown that inter-individual variation in host response to porcine reproductive and respiratory syndrome (prrs) has a heritable component, yet little is known about the underlying genetic architecture of gene expression in response to prrs virus (prrsv) infection. here, we integrated genome-wide genotype, gene expression, viremia level, and weight gain data to identify genetic polymorphisms that are associated with variation in inter-individual gene expression and response to prrsv in ... | 2017 | 28393889 |
| novel analytic tools for the study of porcine reproductive and respiratory syndrome virus (prrsv) in endemic settings: lessons learned in the u.s. | since its emergence in the late 1980's, the porcine reproductive and respiratory syndrome virus (prrsv) has posed a significant challenge to the pig industry worldwide. since then, a number of epidemiological tools have been created to support control and eventual elimination of the disease at the farm and regional levels. still, many aspects of the disease dynamics are yet-to-be elucidated, such as what are the economically optimal control strategies at the farm and regional level, what is the ... | 2016 | 28405429 |
| performance of elisas for detection of antibodies against porcine respiratory and reproductive syndrome virus in serum of pigs after prrsv type 2 live vaccination and challenge. | the aim of the study was to evaluate the performance of different newly developed and/or commercially available elisas for detection of prrsv specific antibodies. consequently, ten prrsv negative piglets (group v) were vaccinated with a prrsv type 2 vaccine. blood samples were taken before as well as seven, 21 and 42 days after vaccination. at day 42 after vaccination (day 0 of the study) all of the piglets from group v and 10 non-prevaccinated prrsv negative piglets (group n) were challenged wi ... | 2015 | 28405425 |