| prevalence and phylogenetic analysis of the isolated type i porcine reproductive and respiratory syndrome virus from 2007 to 2008 in korea. | the first korean strain of porcine reproductive and respiratory syndrome virus (prrsv) was isolated in 1997, and it exhibited high similarity to strain vr-2332 (type ii prrsv; north american type). recently, however, infection with type i prrsv (european type) has also been reported in korea. to date, preliminary data about type i prrsv prevalence in korea have not been reported. here, using reverse transcriptase (rt)-pcr, we analyzed 383 archived field samples from 101 pig farms in korea that w ... | 2010 | 20063118 |
| vaccine efficacy of porcine reproductive and respiratory syndrome virus chimeras. | the vaccine efficacy of six prrsv type 2 infectious clones, including five chimeras and a strain-specific deletion mutant, were examined using a respiratory challenge model in growing swine. the chimeras were constructed from different combinations of a licensed modified live vaccine (ingelvac prrs mlv) and a virulent field isolate (wt mn184) which differ by 14.3% on a nucleotide basis, while the deletion mutant tested had a broad deletion in the nsp2 region of strain mn184. the appearance of an ... | 2010 | 20064475 |
| efficacy of combined porcine reproductive and respiratory syndrome virus and mycoplasma hyopneumoniae vaccination in piglets. | three vaccination challenge studies were performed to evaluate the impact on vaccine efficacy of combining porcine reproductive and respiratory syndrome virus (prrsv) and mycoplasma hyopneumoniae vaccines. piglets were vaccinated with either a m hyopneumoniae bacterin, a modified live prrsv vaccine based on a european-type prrsv strain, or a combination of both vaccines, followed by experimental infection with either m hyopneumoniae or prrsv. vaccine efficacy was evaluated by assessing lung lesi ... | 2010 | 20081177 |
| the m/gp(5) glycoprotein complex of porcine reproductive and respiratory syndrome virus binds the sialoadhesin receptor in a sialic acid-dependent manner. | the porcine reproductive and respiratory syndrome virus (prrsv) is a major threat to swine health worldwide and is considered the most significant viral disease in the swine industry today. in past years, studies on the entry of the virus into its host cell have led to the identification of a number of essential virus receptors and entry mediators. however, viral counterparts for these molecules have remained elusive and this has made rational development of new generation vaccines impossible. t ... | 2010 | 20084110 |
| respiratory function and pulmonary lesions in pigs infected with porcine reproductive and respiratory syndrome virus. | pulmonary dysfunction was evaluated in pigs infected with porcine reproductive and respiratory syndrome virus (prrsv, isolate vr-2332) and compared to clinical and pathological findings. infected pigs developed fever, reduced appetite, respiratory distress and dullness at 9 days post-inoculation (dpi). non-invasive pulmonary function tests using impulse oscillometry and rebreathing of test gases (he, co) revealed peripheral airway obstruction, reduced lung compliance and reduced lung co-transfer ... | 2011 | 20089425 |
| prevalence of antibodies to selected viral and bacterial pathogens in wild boar (sus scrofa) in campania region, italy. | serum samples were collected from wild boars (sus scrofa) harvested during the 2005-2006 hunting season in campania, southern italy. samples were tested for antibodies to leptospira interrogan, brucella spp., salmonella spp., aujeszky disease virus (adv), porcine reproductive and respiratory stress syndrome virus (prrsv), porcine parvovirus (ppv), classical swine fever virus (csfv), and swine vesicular disease virus (svdv). of the 342 serum samples tested, 15 (4.4%) were seropositive to brucella ... | 2010 | 20090052 |
| detection of hepatitis e virus (hev) in italian pigs displaying different pathological lesions. | in this study we investigated the hev prevalence in italian pigs displaying different pathological lesions, possible risk factors related to the infection, and the possible relations occurring between hev and other concomitant pig pathogens. genetic characterization of some of the identified strains was also performed. detection of hev rna was accomplished using a nested reverse-transcription polymerase chain reaction on bile samples from 137 pigs of 2-4months of age submitted for diagnostic pur ... | 2010 | 20092862 |
| [expression and purification of porcine reproductive and respiratory syndrome virus nsp2 protein and analysis of cleavage activity]. | to express and purify porcine reproductive and respiratory syndrome virus nsp2 protein and analyze the protease activity of nsp2. | 2009 | 20112680 |
| origin of highly pathogenic porcine reproductive and respiratory syndrome virus, china. | | 2010 | 20113592 |
| comparative measurement of cell-mediated immune responses of swine to the m and n proteins of porcine reproductive and respiratory syndrome virus. | the principal objectives of this study were to develop autologous antigen-presenting cells (apcs) and to characterize the antigen-specific t-cell responses to the m and n proteins of porcine reproductive and respiratory syndrome virus (prrsv) by using those apcs in outbred pigs. the orf6 and orf7 genes fused with porcine granulocyte-macrophage colony-stimulating factor (gm-csf) were cloned into the mammalian expression vector to generate two plasmid dnas, namely, pcdna3.1-gm-csf-prrsv-m and pcdn ... | 2010 | 20130128 |
| occurrence of mycoplasma hyopneumoniae infections in suckling and nursery pigs in a region of high pig density. | the occurrence of mycoplasma hyopneumoniae infections in young pigs was surveyed in a retrospective study of 1122 datasets obtained from routine diagnostics where either suckling or nursery pigs were examined for m hyopneumoniae in lung tissue. findings were correlated with the presence of lung lesions, detection of other respiratory pathogens, vaccination history and parameters describing the herd of origin. the prevalence of m hyopneumoniae in lung tissue from 201 suckling pigs was 2.0 per cen ... | 2010 | 20154309 |
| genomic analysis of two chinese strains of porcine reproductive and respiratory syndrome viruses with different virulence. | two strains of porcine reproductive and respiratory syndrome virus (prrsv) were isolated, designated gdqj and gdby1. experimental inoculation showed that gdby1, caused 100% morbidity and 67% mortality, while gdqj, caused 100% morbidity but no death. full-length genomes were sequenced. homologic and phylogenetic analyses indicated that these two strains were closely related to chinese highly pathogenic prrsv strains. surprisingly, identical 30 amino acids (aa) deletion in the nsp2-coding region, ... | 2010 | 20155312 |
| prevalence of porcine reproductive and respiratory syndrome virus and porcine circovirus type 2 in piglets after weaning on a commercial pig farm in japan. | to investigate the transition in concentration of porcine reproductive and respiratory syndrome virus (prrsv) and porcine circovirus type 2 (pcv2) and antibody for these viruses in serum, serum samples were collected from 29 pigs on weaning day and at 7, 14, 21, 28, 53, 84, and 120 days after weaning. the concentration of circulated prrsv and pcv2 in serum was measured by real-time rt-pcr and real-time pcr, respectively. the specific antibody for prrsv and pcv2 was measured using elisa. prrsv wa ... | 2010 | 20163685 |
| an investigation of the pathology and pathogens associated with porcine respiratory disease complex in denmark. | respiratory infections are among the most important diseases of growing pigs. in order to elucidate the multifactorial aetiology of porcine respiratory disease complex (prdc) in denmark, lungs from 148 finishing pigs with cranioventral bronchopneumonia (case group) and 60 pigs without lung lesions (control group) were collected from abattoirs. the pathogens involved in prdc and their interactions were identified and linked to the histopathological diagnosis. the lung samples were cultured for ba ... | 2010 | 20181357 |
| expression of inflammatory cytokines and toll-like receptors in the brain and respiratory tract of pigs infected with porcine reproductive and respiratory syndrome virus. | the objective of this experiment was to evaluate the central and peripheral expression of selected pro-inflammatory cytokines and toll-like receptors (tlrs) in pigs infected with porcine reproductive and respiratory syndrome virus (prrsv). twenty-four 8-week-old pigs were inoculated with either sterile medium or prrsv. pigs were monitored 14d after inoculation and then euthanized for tissue sample collection. prrsv was detected in serum, lung and brain tissue of pigs given prrsv but not in any t ... | 2010 | 20189253 |
| the development of oral fluid-based diagnostics and applications in veterinary medicine. | the purpose of this review was to discuss the history of the development and implementation of oral fluid diagnostics for infectious diseases of humans and domestic animals. the use of oral fluid for the assessment of health and diagnosis of disease in humans and animals has a surprisingly long history. as early as 1909, pollaci and ceraulo reported sensitive and specific agglutination of 'micrococcus melitensis' (brucella melitensis) by oral fluid from patients diagnosed with malta fever. a 198 ... | 2010 | 20202287 |
| a dual effect of porcine reproductive and respiratory syndrome virus replication on the phosphatidylinositol-3-kinase-dependent akt pathway. | we have recently shown that porcine reproductive and respiratory syndrome virus (prrsv) can undergo a productive replication in porcine monocyte-derived dendritic cells (mo-dcs). here, we further demonstrate that prrsv activates the host's phosphatidylinositol-3-kinase (pi3k)-dependent akt pathway (pi3k/akt) to facilitate its replication in mo-dcs at 90 min and 4 h after infection. inhibition of pi3k/akt by treatment with a pi3k-specific inhibitor (ly294002) prior to prrsv infection reduced viru ... | 2010 | 20213282 |
| prevalence of antibodies against transmissible gastroenteritis virus and porcine respiratory coronavirus among pigs in six regions in japan. | a total of 2,703 pig sera from 171 farms in six regions in japan were screened for virus-neutralizing (vn) antibody against transmissible gastroenteritis virus (tgev). although none of the farms had clinical signs of transmissible gastroenteritis (tge) or vaccination against tgev, vn antibody was detected in 14.4% of sera at 30 farms (17.5%) across all six regions. on testing of 263 vn antibody-positive sera from 27 farms with a commercial blocking elisa to distinguish tgev and porcine respirato ... | 2010 | 20215723 |
| [construction and immunogenicity of recombinant adenoviruses expressing cap protein of pcv2 and gp5 protein of prrsv in mice]. | porcine circovirus 2 (pcv2) has been implicated as the etiological agent of postweaning multisystemic wasting syndrome (pmws). co-infection of pcv2 and porcine reproductive and respiratory syndrome virus (prrsv) can result in severe economic losses to the swine industry. in this study, we constructed the recombinant adenovirus rad-cap-gp5 expressing cap of pcv2 and gp5 of prrsv. and the expression of cap and gp5 protein in the hek-293 cells inoculated with rad-cap-gp5 were confirmed by immunoper ... | 2009 | 20222461 |
| stability of porcine reproductive and respiratory syndrome virus at ambient temperatures. | the stability of porcine reproductive and respiratory syndrome virus (prrsv) was evaluated for temperatures appropriate to laboratory and field settings. four north american (type 2) isolates (atcc vr-2332, ja-142, mn-184, and ingelvac(r) prrs atp vaccine virus) in cell culture medium (ph 7.5) were held at 1 of 4 temperatures (4, 10, 20, and 30 degrees c) and sampled over time. samples were tested for infectious virus and total prrsv rna using median tissue culture infectious dose and quantitati ... | 2010 | 20224088 |
| phages harboring specific peptides that recognize the n protein of the porcine reproductive and respiratory syndrome virus distinguish the virus from other viruses. | the aim of the current study was to develop a novel diagnostic test for detecting porcine reproductive and respiratory syndrome virus (prrsv) using phage display technology. the n gene of prrsv isolate hh08 was cloned following reverse transcription-pcr. sequence comparison indicated that the n gene shared 96.4% homology to that of north american prrsv (isolate vr2332) and 35.5% with that of european prrsv (isolate lv), indicating that the prrsv isolate was related to the north american prrsv ge ... | 2010 | 20237096 |
| heterologous expression of fused genes encoding the glycoprotein 5 from prrsv: a way for producing functional protein in prokaryotic microorganism. | based on the bioinformatics analysis of the gene encoding glycoprotein 5 (gp5) of porcine reproductive and respiratory syndrome virus (prrsv) isolate hh08, two gene fragments were amplified by polymerase chain reaction (pcr), deleting the signal peptide and transmembrane sequences in gp5 gene. both gene fragments were designated gp5a and gp5b, respectively. they were ligated with a linker and cloned into prokaryotic expression vector, pet-30a. expression of the protein of interest was induced by ... | 2010 | 20356565 |
| isolation and characterization of the first chinese strain of porcine teschovirus-8. | investigations were carried out to identify the causal agent of acute diarrhea, respiratory distress, and death of pigs on a swine farm in jilin province, northern china. only porcine teschovirus (ptv, designated as ptv-8 jilin/2003) was isolated from samples of organs. the presence of ptv was confirmed by the production of a specific cytopathic effect on susceptible cells and by the results of the immunoperoxidase monolayer assay (ipma), polymerase chain reaction, and electron microscopy. other ... | 2010 | 20362007 |
| purification of porcine reproductive and respiratory syndrome virus from cell culture using ultrafiltration and heparin affinity chromatography. | porcine reproductive and respiratory syndrome (prrs) virus is the causative agent of the most significant infectious disease currently affecting the swine industry worldwide. density gradient ultracentrifugation remains the most commonly used method for porcine reproductive and respiratory syndrome virus (prrsv) purification. however, this technique has notable drawbacks including long processing time and limited processing volume in each run. to overcome these limitations, a scalable process wa ... | 2010 | 20371065 |
| interleukin-8, interleukin-1beta, and interferon-gamma levels are linked to prrs virus clearance. | infection with porcine reproductive and respiratory syndrome virus (prrsv) results in a weak antiviral immune response that leads to a persistent infection in a subset of pigs. we investigated the intensity and timing of the early cytokine responses to prrsv infection to determine their utility as a predictor of persistence. as part of the "big pig" project, we evaluated cytokine gene expression in lymphoid tissues collected from pigs for up 202 days post-infection (dpi); serum samples were coll ... | 2010 | 20373993 |
| the role of porcine reproductive and respiratory syndrome (prrs) virus structural and non-structural proteins in virus pathogenesis. | porcine reproductive and respiratory syndrome (prrs) is an economically devastating viral disease affecting the swine industry worldwide. the etiological agent, prrs virus (prrsv), possesses a rna viral genome with nine open reading frames (orfs). the orf1a and orf1b replicase-associated genes encode the polyproteins pp1a and pp1ab, respectively. the pp1a is processed in nine non-structural proteins (nsps): nsp1α, nsp1β, and nsp2 to nsp8. proteolytic cleavage of pp1ab generates products nsp9 to ... | 2010 | 20388230 |
| differential cellular protein expression in continuous porcine alveolar macrophages regulated by the porcine reproductive and respiratory syndrome virus nucleocapsid protein. | porcine reproductive and respiratory syndrome virus (prrsv) is a leading cause of significant economic losses in the pig industry worldwide. prrsv infects preferentially porcine alveolar macrophages (pams) and subsequently utilizes the host cell biosynthetic machinery for its own replication. to date, a number of studies have been conducted to investigate compensatory changes of cellular gene expression of pams upon prrsv infection. however, very little information exists about differential cell ... | 2010 | 20394785 |
| plasmid containing cpg oligodeoxynucleotides can augment the immune responses of pigs immunized with porcine reproductive and respiratory syndrome killed virus vaccine. | porcine reproductive and respiratory syndrome virus (prrsv), the causative agent of porcine reproductive and respiratory syndrome (prrs), causes serious health problems in swine, resulting in great economic losses to the swine industry worldwide. the porcine reproductive and respiratory syndrome (prrs) killed virus (kv) vaccine has been widely used in china but has been linked with side effects in pigs and only partial protection. a few studies have demonstrated the immunostimulatory adjuvant ef ... | 2010 | 20394988 |
| differential expression and activity of the porcine type i interferon family. | type i interferons (ifns) are central to innate and adaptive immunity, and many have unique developmental and physiological functions. however, in most species, only two subtypes, ifn-alpha and ifn-beta, have been well studied. because of the increasing importance of zoonotic viral diseases and the use of pigs to address human research questions, it is important to know the complete repertoire and activity of porcine type i ifns. here we show that porcine type i ifns comprise at least 39 functio ... | 2010 | 20406849 |
| nitric oxide is elicited and inhibits viral replication in pigs infected with porcine respiratory coronavirus but not porcine reproductive and respiratory syndrome virus. | there is little information on the role of nitric oxide (no) in innate immunity to respiratory coronavirus (cov) infections. we examined no levels by greiss assay in bronchoalveolar lavage (bal) of pigs infected with either porcine respiratory coronavirus (prcv) or porcine reproductive and respiratory syndrome virus (prrsv), a member of nidovirales, like cov. the antiviral effects of no on these two viruses were tested in an in vitro system using a no donor, s-nitroso-n-acetylpenicillamine (snap ... | 2010 | 20409593 |
| the crystal structure of porcine reproductive and respiratory syndrome virus nonstructural protein nsp1beta reveals a novel metal-dependent nuclease. | porcine reproductive and respiratory syndrome virus (prrsv), a member of the arteriviridae family of nidovirales, is the causative agent of porcine reproductive and respiratory syndrome, which results in enormous economic losses in the swine industry. as the second protein encoded by the prrsv genome, nsp1beta cleaves itself from the downstream nsp2 protein via a c-terminal papain-like cysteine protease (pcp) domain. although nsp1beta is known to be involved in virulence, its precise role in the ... | 2010 | 20410261 |
| porcine reproductive and respiratory syndrome virus entry into the porcine macrophage. | porcine reproductive and respiratory syndrome virus (prrsv) emerged in the late 1980s and rapidly became one of the most significant viral pathogens in the swine industry. in vivo, the virus shows a very narrow cell tropism and targets specific subsets of porcine macrophages. the entry of prrsv into its host cell is the first crucial step in infection and has been the focus of many fundamental studies. this review provides a comprehensive overview of the current knowledge on prrsv entry into the ... | 2010 | 20410315 |
| modulation of type i interferon induction by porcine reproductive and respiratory syndrome virus and degradation of creb-binding protein by non-structural protein 1 in marc-145 and hela cells. | porcine reproductive and respiratory syndrome (prrs) is an emerged disease of swine characterized by negligible response of type i ifns and viral persistence. we show that the prrsv non-structural protein 1 (nsp1) is the viral component responsible for modulation of ifn response. nsp1 blocked dsrna-induced irf3 and ifn promoter activities. nsp1 did not block phosphorylation and nuclear translocation of irf3 but inhibited irf3 association with creb-binding protein (cbp) in the nucleus. while irf3 ... | 2010 | 20416917 |
| long-distance airborne transport of infectious prrsv and mycoplasma hyopneumoniae from a swine population infected with multiple viral variants. | airborne transport of porcine reproductive and respiratory syndrome virus (prrsv) and mycoplasma hyopneumoniae (m hyo) has been reported out to 4.7 km. this study attempted to determine whether this event could occur over longer distances and across multiple viral variants. to accomplish this goal, a mixed infection of 3 prrsv variants (1-8-4, 1-18-2 and 1-26-2) and m hyo 232 was established in a source population of growing pigs. over 21-day period, air samples were collected from the source po ... | 2010 | 20418029 |
| immune responses in pigs induced by recombinant canine adenovirus 2 expressing the glycoprotein 5 of porcine reproductive and respiratory syndrome virus. | to develop a new type vaccine for porcine reproductive and respiratory syndrome (prrs) prevention by using canine adenovirus 2(cav-2) as vector, the glycoprotein 5(gp5) gene from prrsv strain jl was amplified by rt-pcr, and the expression cassette of gp5 was constructed using the human cytomegalovirus (hcmv) promoter and the simian virus 40 (sv40) early mrna polyadenylation signal. the expression cassette of glycoprotein 5 was cloned into the cav-2 genome in which e3 region had been partly delet ... | 2010 | 20432066 |
| variation in resistance to the porcine reproductive and respiratory syndrome virus (prrsv) in pietrain and miniature pigs. | porcine reproductive and respiratory syndrome (prrs) is one of the economically most important diseases of swine. viraemia and the prolonged persistence of the virus are among the most critical factors. virus replication and severity of disease vary with virus isolates, and there is rising evidence for a genetic component of the host susceptibility. dissecting the genetic basis of resistance/susceptibility to prrs virus (prrsv) might lead to improved knowledge on the molecular mechanisms of prrs ... | 2010 | 20433517 |
| analysis of synonymous codon usage in porcine reproductive and respiratory syndrome virus. | in this study, we calculated the relative synonymous codon usage (rscu) values and codon usage bias (cub) values to implement a comparative analysis of codon usage pattern of open reading frames (orfs) which belong to the two main genotypes of porcine reproductive and respiratory syndrome virus (prrsv). by analysis of synonymous codon usage values in each orf of prrsv, the optimal codons for most amino acids were all c or g-ended codons except gau for asp, cau for his, uuu for phe and ccu for pr ... | 2010 | 20438864 |
| an outbreak of lethal toxoplasmosis in pigs in the gansu province of china. | in october 2004, a swine farm in jinchang, gansu province, china, experienced an outbreak of toxoplasmosis. most of the affected pigs had a rectal temperature greater than 40 degrees c and gradually lost their appetite. morbidity reached 57%, and mortality was approximately 2%. analysis of blood samples from affected pigs using hemagglutination inhibition (hi) assay, immunoglobulin g-enzyme-linked immunosorbent assay (igg-elisa), and igm-elisa tests showed high titers of anti-toxoplasma gondii a ... | 2010 | 20453223 |
| development and characterization of stable cell lines constitutively expressing the porcine reproductive and respiratory syndrome virus nucleocapsid protein. | despite global efforts to control porcine reproductive and respiratory syndrome virus (prrsv) infection, the virus continues to cause economic problems in the swine industry worldwide. in this study, we attempted to generate and characterize a panel of stable bhk cell lines that constitutively express the nucleocapsid (n) protein of type 1 or type 2 prrsv. the established bhk cell lines were found to react well with n-specific antibodies as well as the hyperimmune serum of pigs raised against ea ... | 2010 | 20458160 |
| the development of a rapid sybr one step real-time rt-pcr for detection of porcine reproductive and respiratory syndrome virus. | prompt detection of prrsv in the field samples is important for effective prrs control, thereby reducing the potentially serious economic damage which can result from an outbreak. in this study, a rapid sybr-based, one step real-time rt-pcr quantitative reverse transcription pcr (qrt-pcr) has been developed for the detection of porcine reproductive and respiratory syndrome virus (prrsv). primers were designed based on the sequence of highly conservative region of prrsv n gene. | 2010 | 20459705 |
| construction and characterization of a recombinant canine adenovirus expressing gp5 and m proteins of porcine reproductive and respiratory syndrome virus. | the causative agent of porcine reproductive and respiratory syndrome (prrs) is prrs virus (prrsv), which belongs to the family arteriviridae. gp5/m protein complex of prrsv binds to sialoadhesion expressed on the cells to infect the cells. in this study, we developed a canine adenovirus type 2 (cav-2) recombinant, termed rcav2-gp5/m, expressing gp5 and m proteins. to evaluate the immunogenicity of the recombinant virus, mice were inoculated subcutaneously with rcav2-gp5/m, and specific antibodie ... | 2010 | 20467206 |
| phylogenetic analysis and molecular characteristics of seven variant chinese field isolates of prrsv. | porcine reproductive and respiratory syndrome (prrs) has now been widely recognized as an economically important disease. the objective of this study was to compare the molecular and biological characteristics of porcine reproductive and respiratory syndrome virus (prrsv) field isolates in china to those of the modified live virus (mlv) prrs vaccine and its parent strain (atcc vr2332). | 2010 | 20482897 |
| development of an 8-plex luminex assay to detect swine cytokines for vaccine development: assessment of immunity after porcine reproductive and respiratory syndrome virus (prrsv) vaccination. | a luminex (luminex corp., austin, tx) multiplex swine cytokine assay was developed to measure 8 cytokines simultaneously in pig serum for use in assessment of vaccine candidates. the fluorescent microsphere immunoassay (fmia) was tested on archived sera in a porcine reproductive and respiratory syndrome virus (prrsv) vaccine/challenge study. this fmia simultaneously detects innate (il-1 beta, il-8, ifn-alpha, tnf-alpha, il-12), regulatory (il-10), th1 (ifn-gamma) and th2 (il-4) cytokines. these ... | 2010 | 20488263 |
| deletion of the cytoplasmic domain of cd163 enhances porcine reproductive and respiratory syndrome virus replication. | the macrophage scavenger receptor cd163 is a major determinant for the entry of porcine reproductive and respiratory syndrome virus (prrsv). the present study was undertaken to assess the functional significance of the intracellular region of cd163 for prrsv infection. we stably transfected non-susceptible bhk cells with plasmids encoding full-length and cytoplasmic-domain-deleted (tailless) cd163 and evaluated their permissiveness to prrsv. the experimental data revealed that the tailless cd163 ... | 2010 | 20496088 |
| proteome changes of lungs artificially infected with h-prrsv and n-prrsv by two-dimensional fluorescence difference gel electrophoresis. | porcine reproductive and respiratory syndrome with prrs virus (prrsv) infection, which causes significant economic losses annually, is one of the most economically important diseases affecting swine industry worldwide. in 2006 and 2007, a large-scale outbreak of highly pathogenic porcine reproductive and respiratory syndrome (prrs) happened in china and vietnam. however little data is available on global host response to prrsv infection at the protein level, and similar approaches looking at mrn ... | 2010 | 20504321 |
| the cysteine protease domain of porcine reproductive and respiratory syndrome virus nonstructural protein 2 possesses deubiquitinating and interferon antagonism functions. | porcine reproductive and respiratory syndrome (prrs) virus nonstructural protein 2 (nsp2) contains a cysteine protease domain at its n terminus, which belongs to the ovarian tumor (otu) protease family. in this study, we demonstrated that the prrsv nsp2 otu domain antagonizes the type i interferon induction by interfering with the nf-kappab signaling pathway. further analysis revealed that the nsp2 otu domain possesses ubiquitin-deconjugating activity. this domain has the ability to inhibit nf-k ... | 2010 | 20504922 |
| the genomic diversity of chinese porcine reproductive and respiratory syndrome virus isolates from 1996 to 2009. | since it was first reported in 1995, porcine reproductive and respiratory syndrome (prrs) has become one of the most important swine diseases in china. a large number of field prrsv strains have been isolated from different regions of china at different times, especially after a highly pathogenic prrsv emerged in 2006. previous studies based on orf5 gene sequences revealed extensive genetic diversity among chinese prrsv isolates. to fully understand the extent of genetic diversity of prrsv in ch ... | 2010 | 20510553 |
| pathogenesis and antigenic characterization of a new east european subtype 3 porcine reproductive and respiratory syndrome virus isolate. | porcine reproductive and respiratory syndrome virus (prrsv) is divided into a european and north american genotype. east european prrsv isolates have been found to be of the european genotype, but form different subtypes. in the present study, prrsv was isolated from a belarusian farm with reproductive and respiratory failure and designated "lena". analyses revealed that lena is a new east european subtype 3 prrsv isolate. the main purpose of this investigation was to study the pathogenesis and ... | 2010 | 20525333 |
| porcine reproductive and respiratory syndrome virus replication is suppressed by inhibition of the extracellular signal-regulated kinase (erk) signaling pathway. | viruses are known to develop the ability to manipulate a variety of host cell signal transduction pathways in order to facilitate successful virus survival. however, to date, little is known about the intracellular signaling mechanisms involved in porcine reproductive and respiratory syndrome virus (prrsv) replication. the extracellular signal-regulated kinase (erk) pathway that transduces signals to modulate a wide range of cellular functions has been shown to regulate a number of viral infecti ... | 2010 | 20540975 |
| prevention of prrsv infection in large breeding herds using air filtration. | | 2010 | 20543168 |
| haptoglobin and c-reactive protein as biomarkers in the serum, saliva and meat juice of pigs experimentally infected with porcine reproductive and respiratory syndrome virus. | concentrations of the acute phase proteins haptoglobin (hp) and c-reactive protein (crp) were measured in the serum, saliva and meat juice of pigs experimentally infected with a porcine reproductive and respiratory syndrome virus (prrsv) field isolate. sixteen prrsv-free pigs were inoculated im, killed in groups of four at 7, 14, 21 and 24 days post-inoculation (dpi), and samples of blood, saliva and diaphragmatic muscle were collected. four non-infected controls were killed at 24 dpi. significa ... | 2010 | 20554227 |
| phylogeny-based evolutionary, demographical, and geographical dissection of north american type 2 porcine reproductive and respiratory syndrome viruses. | type 2 (or north american-like) porcine reproductive and respiratory syndrome virus (prrsv) was first recorded in 1987 in the united states and now occurs in most commercial swine industries throughout the world. in this study, we investigated the epidemiological and evolutionary behaviors of type 2 prrsv. based on phylogenetic analyses of 8,624 orf5 sequences, we described a comprehensive picture of the diversity of type 2 prrsvs and systematically classified all available sequences into lineag ... | 2010 | 20554771 |
| selected swine viral pathogens in indoor pigs in spain. seroprevalence and farm-level characteristics. | a serosurvey on porcine reproductive and respiratory syndrome virus (prrsv), swine influenza virus (siv), aujeszky's disease virus ge protein (adv ge), porcine parvovirus (ppv) and porcine circovirus type 2 (pcv2) was carried out in spanish pig herds. the serosurvey consisted of two studies. first, a retrospective study assessed the proportion of seropositive boar, sow and fattening pig herds and their seroprevalences to prrsv, siv, adv ge and ppv from 2003 to 2005 and to pcv2 from 2000 to 2005. ... | 2010 | 20569418 |
| the immunogenicity of dna constructs co-expressing gp5 and m proteins of porcine reproductive and respiratory syndrome virus conjugated by gpgp linker in pigs. | the heterodimer of glycoprotein 5 (gp5) and non-glycosylated matrix protein (m) is the leading target for the development of new generation of vaccines against porcine reproductive and respiratory syndrome virus (prrsv) infection. it has been demonstrated that dna vaccine co-expressing gp5 and m proteins as a fusion protein aroused better immunogenicity than that expressing gp5 or m alone, but it was no better than the dna vaccine co-expressing gp5 and m proteins with two different promoters. al ... | 2010 | 20570063 |
| susceptible cell lines for the production of porcine reproductive and respiratory syndrome virus by stable transfection of sialoadhesin and cd163. | porcine reproductive and respiratory syndrome virus (prrsv) causes major economic losses in the pig industry worldwide. in vivo, the virus infects a subpopulation of tissue macrophages. in vitro, prrsv only replicates in primary pig macrophages and african green monkey kidney derived cells, such as marc-145. the latter is currently used for vaccine production. however, since virus entry in marc-145 cells is different compared to entry in primary macrophages, specific epitopes associated with vir ... | 2010 | 20587060 |
| distribution of genotypes of porcine reproductive and respiratory syndrome virus in ontario during 2004-2007 and the association between genotype and clinical signs of disease. | restriction fragment length polymorphism (rflp) was first proposed to classify porcine reproductive and respiratory syndrome virus (prrsv) in 1998. the primary objective of this study was to identify associations between different prrsv rflp types in swine herds in southern ontario and clinical signs of disease in those herds. herds included in the study submitted samples to the animal health laboratory at the university of guelph between september 2004 and august 2007. each farm owner was surve ... | 2010 | 20592841 |
| comparative evaluation of prrs virus infection in vaccinated and naïve pigs. | the purpose of this study was to evaluate the time-course of the immune response to a field porcine respiratory and reproductive syndrome virus (prrsv) strain in prrs-naïve, untreated pigs, as well as in four groups of age and breed-matched pigs injected with a live attenuated prrs vaccine, its adjuvant, an inactivated prrs vaccine and an irrelevant, inactivated porcine circovirus type 2 (pcv2) vaccine, respectively. prrsv infection was confirmed in all groups by pcr and antibody assays. the ant ... | 2011 | 20598328 |
| vectored vaccines to protect against prrsv. | prrsv is the causative agent of the most important infectious disease affecting swine herds worldwide, producing great economic losses. commercially available vaccines are only partially effective in protection against prrsv. moreover, modified live vaccines may allow virus shedding, and could revert generating virulent phenotypes. therefore, new efficient vaccines are required. vaccines based on recombinant virus genomes (virus vectored vaccines) against prrsv could represent a safe alternative ... | 2010 | 20600388 |
| subcellular localization and topology of porcine reproductive and respiratory syndrome virus e protein. | porcine reproductive and respiratory syndrome virus (prrsv) open reading frame (orf) 2a contains a small internal orf (2b) capable of encoding a protein of 70 or 73 amino acids (aa), termed e protein. the function and biochemical information of the e protein are currently not clear. in the present investigation, it was shown that the e protein was mainly located in the endoplasmic reticulum (er) and golgi complex in marc-145 cells. deletion studies identified the n-terminal 15 residues as an er ... | 2010 | 20600392 |
| understanding prrsv infection in porcine lung based on genome-wide transcriptome response identified by deep sequencing. | porcine reproductive and respiratory syndrome (prrs) has been one of the most economically important diseases affecting swine industry worldwide and causes great economic losses each year. prrs virus (prrsv) replicates mainly in porcine alveolar macrophages (pams) and dendritic cells (dcs) and develops persistent infections, antibody-dependent enhancement (ade), interstitial pneumonia and immunosuppression. but the molecular mechanisms of prrsv infection still are poorly understood. here we repo ... | 2010 | 20614006 |
| pathogenicity and molecular characterization of emerging porcine reproductive and respiratory syndrome virus in vietnam in 2007. | in 2007, vietnam experienced swine disease outbreaks causing clinical signs similar to the 'porcine high fever disease' that occurred in china during 2006. analysis of diagnostic samples from the disease outbreaks in vietnam identified porcine reproductive and respiratory syndrome virus (prrsv) and porcine circovirus type 2 (pcv-2). additionally, escherichia coli and streptococcus equi subspecies zooepidemicus were cultured from lung and spleen, and streptococcus suis from one spleen sample. gen ... | 2010 | 20629970 |
| dynamic changes in inflammatory cytokines in pigs infected with highly pathogenic porcine reproductive and respiratory syndrome virus. | porcine reproductive and respiratory syndrome virus (prrsv) infection induces both humoral and cellular immune responses. in this study, we investigated the changes in cytokine levels in peripheral blood between the highly pathogenic prrsv hun4 strain and its derivative strain hun4-f112 obtained by serial propagation in marc145 cells to 112 passages. the results demonstrated that pigs infected with hun4 showed a loss of appetite, decrease in body weight, raised body temperature, and respiratory ... | 2010 | 20631336 |
| genomic structure and characterization of mrna expression pattern of porcine interferon gamma receptor 1 gene. | interferon gamma receptor (ifngr) plays an important role in the biological effects of ifn-γ. in this study, porcine ifngr1 cdna was cloned and two transcripts both having a coding region of 1413 bp were identified. porcine ifngr1 cdna shares 62.95%, 63.73%, 72.90% and 81.10% identity in nucleotide sequence; and 45.64%, 46.69%, 58.04% and 72.55% homology in amino acid sequence to those of rat, mouse, human and cattle, respectively. the porcine ifngr1 genomic structure consists of seven exons and ... | 2010 | 20637044 |
| effect of an interferon-stimulated response element (isre) mutant of porcine circovirus type 2 (pcv2) on pcv2-induced pathological lesions in a porcine reproductive and respiratory syndrome virus (prrsv) co-infection model. | porcine circovirus type 2 (pcv2) is the primary causative agent of porcine circovirus-associated diseases (pcvad) in swine. coinfections of pcv2 with other swine pathogens increase the severity of pcvad. induction of proinflammatory cytokines by coinfecting pathogens may attribute to the exacerbation of pcvad during coinfections. an interferon-stimulated response element (isre) sequence was identified in the origin of replication of pcv2 genome. to assess the role of isre in pcv2 pathogenesis du ... | 2011 | 20637549 |
| comparison of commercial and experimental porcine circovirus type 2 (pcv2) vaccines using a triple challenge with pcv2, porcine reproductive and respiratory syndrome virus (prrsv), and porcine parvovirus (ppv). | the efficacies of commercial porcine circovirus type 2 (pcv2) vaccines and a live pcv1-2a chimeric vaccine were compared in conventional, pcv2-positive piglets using a pcv2-porcine reproductive and respiratory syndrome virus (prrsv)-porcine parvovirus (ppv) coinfection challenge model. seventy-three, 2-week-old pigs were randomized into seven groups including five vaccinated and two control groups. pigs in the vaccinated groups were vaccinated at 3 weeks (one dose) or at 3 and 6 weeks (two dose) ... | 2010 | 20637768 |
| accelerated evolution of prrsv during recent outbreaks in china. | porcine reproductive and respiratory syndrome virus (prrsv) is reported to have evolved at a higher evolutionary rate than other rna viruses. however, whether this virus is capable of evolutionary acceleration during outbreaks remains unknown. in this study, we analyze the data based on orfs of eight newly obtained epidemic prrsvs from hebei province with other viral genomes from genbank. phylogenetic analysis suggested that all isolates during recent outbreaks (2006-2008) are grouped together. ... | 2010 | 20652733 |
| cytokine expression, glucocorticoid and growth hormone changes after porcine reproductive and respiratory syndrome virus (prrsv-1) infection in vaccinated and unvaccinated naturally exposed pigs. | the objective of this paper was to study the changes of some cytokines and neuroendocrine hormones in vaccinated and unvaccinated pigs that were naturally infected by a prrsv-1 (porcine reproductive and respiratory syndrome virus) heterologous field strain. we analyzed gene expression of pro-inflammatory (tnf-α, il-1β, mcp-1, il-6), pro-immune (ifn-γ) and anti-inflammatory cytokines (il-10) in pbmc, as well as hormonal (gh and cortisol) levels in blood samples of pigs obtained in a field trial p ... | 2011 | 20655592 |
| novel strategies and approaches to develop the next generation of vaccines against porcine reproductive and respiratory syndrome virus (prrsv). | porcine reproductive and respiratory syndrome virus (prrsv) is an economically important swine pathogen. since its discovery in the early 1990 s, tremendous progresses have been made in understanding the molecular biology and pathogenesis of prrsv. although modified live-attenuated vaccines (mlvs) and inactivated vaccines against prrsv have been available for more than a decade, the disease remains difficult to control. the efficacies of these vaccines especially against heterologous strains rem ... | 2010 | 20655962 |
| modulation of host cell responses and evasion strategies for porcine reproductive and respiratory syndrome virus. | the immune surveillance system protects host cells from viral infection, and viruses have evolved to escape this system for efficient proliferation in the host. host cells produce cytokines and chemokines in response to viral infection, and among such effector molecules, type i interferons are the principal antiviral cytokines and therefore effective targets for viruses to disarm host surveillance. porcine reproductive and respiratory syndrome virus (prrsv) expresses proteins that circumvent the ... | 2010 | 20655963 |
| a brief review of cd163 and its role in prrsv infection. | porcine reproductive and respiratory syndrome virus (prrsv) infects fully differentiated cells of the monocyte/macrophage lineage. recently, cd163 was shown to be a cellular receptor capable of mediating infection of otherwise prrsv non-permissive cell lines. cd163 is a macrophage differentiation antigen belonging to the scavenger receptor cysteine-rich (srcr) family of membrane proteins. we provide a brief review of current knowledge regarding cd163 in relation to prrsv infection, and propose a ... | 2010 | 20655964 |
| porcine reproductive and respiratory syndrome in china. | porcine reproductive and respiratory syndrome (prrs) is an economically important viral disease for the pig industry worldwide. this disease has brought great losses to the chinese pig production in recent years, particularly following the emergence of the highly pathogenic prrs virus (prrsv), and has become an intractable problem for the development of pig industry in china. this paper will review the history of prrs, the epidemic of atypical prrs caused by the highly pathogenic virus, and the ... | 2010 | 20659506 |
| certainties, doubts and hypotheses in porcine reproductive and respiratory syndrome virus immunobiology. | porcine reproductive and respiratory syndrome virus (prrsv) is one of the most costly pathogens for the swine industry. since its emergence some 20 years ago, much has been learned about the immunobiology of prrsv. although vaccines are available, they do not provide full and universal protection against prrsv infection. in the present review, current knowledge on the virus's immunobiology will be discussed including: role of viral receptors, innate immune response to the virus, regulation of th ... | 2010 | 20659507 |
| use of a production region model to assess the efficacy of various air filtration systems for preventing airborne transmission of porcine reproductive and respiratory syndrome virus and mycoplasma hyopneumoniae: results from a 2-year study. | porcine reproductive and respiratory syndrome virus (prrsv) and mycoplasma hyopneumoniae (m hyo) are economically significant pathogens of pigs that can be spread between herds via the airborne route. as area/regional control and eradication programs for these pathogens move forward, it becomes critical to understand conditions associated with airborne transport and to develop strategies to reduce this risk. while merv 16-based air filtration is a potential intervention, it is costly and has onl ... | 2010 | 20667494 |
| complete genomic characterization of a chinese isolate of porcine reproductive and respiratory syndrome virus. | the genome of one isolate of porcine reproductive and respiratory syndrome virus (prrsv) from china, designated gdqy2, was sequenced and analyzed. the full length of gdqy2 was 15,215 nucleotides, excluding the poly(a) tail. comparative analysis with the genomic sequences of numerous worldwide north american isolates revealed that gdqy2 shared 85.0-98.9% identity with these isolates, but only 60.9% with the european virus-lv (lelystad virus), indicating that this new chinese isolate was closely r ... | 2011 | 20667670 |
| proteolytic products of the porcine reproductive and respiratory syndrome virus nsp2 replicase protein. | the nsp2 replicase protein of porcine reproductive and respiratory syndrome virus (prrsv) was recently demonstrated to be processed from its precursor by the pl2 protease at or near the g(1196)|g(1197) dipeptide in transfected cho cells. here the proteolytic cleavage of prrsv nsp2 was further investigated in virally infected marc-145 cells by using two recombinant prrsvs expressing epitope-tagged nsp2. the data revealed that prrsv nsp2 exists as different isoforms, termed nsp2a, nsp2b, nsp2c, ns ... | 2010 | 20668084 |
| porcine reproductive and respiratory syndrome virus (prrsv) in serum and oral fluid samples from individual boars: will oral fluid replace serum for prrsv surveillance? | the purpose of this study was to determine whether oral fluid samples could be used to monitor individually-housed adult boars for porcine reproductive and respiratory syndrome virus (prrsv) infection. in 3 trials, 24 boars were intramuscularly (im) inoculated with a modified-live prrsv (mlv) vaccine (trial 1), a type 1 prrsv isolate (trial 2), or a type 2 isolate (trial 3). oral fluid samples were collected daily and serum samples were collected twice weekly. following the completion of the stu ... | 2010 | 20670665 |
| in vivo growth of porcine reproductive and respiratory syndrome virus engineered nsp2 deletion mutants. | prior studies on prrsv strain vr-2332 non-structural protein 2 (nsp2) had shown that as much as 403 amino acids could be removed from the hypervariable region without losing virus viability in vitro. we utilized selected nsp2 deletion mutants to examine in vivo growth. young swine (4 pigs/group; 5 control swine) were inoculated intramuscularly with one of 4 nsp2 deletion mutants (rδ727-813, rδ543-726, rδ324-523, rδ324-726) or full-length recombinant virus (rvr-2332). serum samples were collected ... | 2010 | 20673840 |
| n-acetylpenicillamine inhibits the replication of porcine reproductive and respiratory syndrome virus in vitro. | nitric oxide (no) was proposed to be an important molecule against some microorganisms. in this study, we investigated the inhibitory effect of no on the infection by porcine reproductive and respiratory syndrome virus (prrsv) in vitro and the role of no in the defense against prrsv. our results indicated that exogenous no did not inhibit prrsv infection. unexpectedly, n-acetylpenicillamine (nap), a commonly used compound as negative control for no-producing reagents, inhibited prrsv replication ... | 2010 | 20676761 |
| loop-mediated isothermal amplification for rapid detection and differentiation of wild-type pseudorabies and gene-deleted virus vaccines. | a loop-mediated isothermal amplification (lamp) assay was developed specifically for detection and differentiation of pseudorabies virus (prv). one group of primers was designed to detect wild-type strains (i.e., strains with the ge gene) and the other group of primers was designed to detect both prv ge-vaccine and wild-type strains (i.e., strains with the gg gene and with or without the ge gene). after amplification by bst enzyme at a constant temperature of 65 degrees c, a laddering of bright ... | 2010 | 20691214 |
| a prospective study evaluating duration of swine breeding herd prrs virus-free status and its relationship with measured risk. | a variety of methods for eliminating the prrs virus from pig production sites have been successfully applied. however, success in maintaining a prrs virus-free status for extended periods of time following elimination has been inconsistent and unpredictable. the objective of this study was to evaluate whether risks measured using version 1 of the american association of swine veterinarians (aasv) prrs risk assessment for the breeding herd, season of year and method by which swine breeding herd s ... | 2010 | 20692057 |
| the structural biology of prrsv. | porcine reproductive and respiratory syndrome virus (prrsv) is an enveloped, positive-sense single-stranded rna virus belonging to the arteriviridae family. arteriviruses and coronaviruses are grouped together in the order nidovirales, based on similarities in genome organization and expression strategy. over the past decade, crystal structures of several viral proteins, electron microscopic studies of the virion, as well as biochemical and in vivo studies on protein-protein interactions have le ... | 2010 | 20692304 |
| porcine reproductive and respiratory syndrome virus (prrsv) could be sensed by professional beta interferon-producing system and had mechanisms to inhibit this action in marc-145 cells. | porcine reproductive and respiratory syndrome virus (prrsv) causes an economically important disease in swine-producing area, and interferon beta (ifn-beta) is the first responder against the animal virus infection. however, whether prrsv could induce the production of ifn-beta is controversial. in this paper, we first time found that prrsv could phosphorylate ifn-regulatory factor 3 (irf-3) and weakly activate the ifn-beta promoter in marc-145 cells in early infection, but the activations of ir ... | 2010 | 20692306 |
| secondary infection with streptococcus suis serotype 7 increases the virulence of highly pathogenic porcine reproductive and respiratory syndrome virus in pigs. | porcine reproductive and respiratory syndrome virus (prrsv) and streptococcus suis are common pathogens in pigs. in samples collected during the porcine high fever syndrome (phfs) outbreak in many parts of china, prrsv and s. suis serotype 7 (ss7) have always been isolated together. to determine whether prrsv-ss7 coinfection was the cause of the phfs outbreak, we evaluated the pathogenicity of prrsv and/or ss7 in a pig model of single and mixed infection. | 2010 | 20696031 |
| the prrsv replicase: exploring the multifunctionality of an intriguing set of nonstructural proteins. | our knowledge about the structure and function of the nonstructural proteins (nsps) encoded by the arterivirus replicase gene has advanced in recent years. the continued characterization of the nsps of the arterivirus prototype equine arteritis virus has not only corroborated several important functional predictions, but also revealed various novel features of arteriviral replication. for porcine reproductive and respiratory syndrome virus (prrsv), based on bioinformatics predictions and experim ... | 2010 | 20696193 |
| longitudinal study of respiratory infection patterns of breeding sows in five farrow-to-finish herds. | a longitudinal study was carried out in five french farrow-to-finish herds differently affected by respiratory diseases to describe the carrying and infection patterns of batches of sows to various respiratory pathogens during gestation and lactation. an entire batch of sows was followed during two successive reproduction cycles. nasal, tonsillar and oro-pharyngeal swabs and blood samples were taken from each sow 9 and 4 weeks before farrowing and 1 and 4 weeks after farrowing. mycoplasma hyopne ... | 2011 | 20696539 |
| establishment of a multiplex rt-pcr assay to detect different lineages of swine h1 and h3 influenza a viruses. | classical swine h1n1, emerging european avian-like h1n1 and human-like h3n2 lineages are co-circulating in the swine population in china. the reverse transcriptase polymerase chain reaction (rt-pcr) assay is an effective method for use in influenza surveillance. in this study, a multiplex rt-pcr method was developed for simultaneous identification of hemagglutinin (ha) genes derived from the three lineages of swine influenza viruses. three primer sets were designed and aimed specifically at ha g ... | 2010 | 20700759 |
| porcine reproductive and respiratory syndrome virus non-structural protein 1 suppresses tumor necrosis factor-alpha promoter activation by inhibiting nf-κb and sp1. | the objective of this study was to identify porcine reproductive and respiratory syndrome virus (prrsv)-encoded proteins that are responsible for the inhibition of tnf-α expression and the mechanism(s) involved in this phenomenon. using a tnf-α promoter reporter system, the non-structural protein 1 (nsp1) was found to strongly suppress the tnf-α promoter activity. such inhibition takes place especially at the promoter's proximal region. both nsp1α and nsp1β, the two proteolytic fragments of nsp1 ... | 2010 | 20701940 |
| genetic control of host resistance to porcine reproductive and respiratory syndrome virus (prrsv) infection. | this manuscript focuses on the advances made using genomic approaches to identify biomarkers that define genes and pathways that are correlated with swine resistance to infection with porcine reproductive and respiratory syndrome virus (prrsv), the most economically important swine viral pathogen worldwide. international efforts are underway to assess resistance and susceptibility to infectious pathogens using tools such as gene arrays, single nucleotide polymorphisms (snps) chips, genome-wide a ... | 2010 | 20709118 |
| a variable region in gp4 of european-type porcine reproductive and respiratory syndrome virus induces neutralizing antibodies against homologous but not heterologous virus strains. | porcine reproductive and respiratory syndrome virus (prrsv) can induce severe reproductive failure in sows, and is involved in the porcine respiratory disease complex. the glycoprotein gp4 of the european prototype prrsv strain lelystad virus (lv) contains a linear neutralizing epitope that is located in a highly variable region. the current study aimed to evaluate the antibody response against this and other epitopes on gp4 to infection of pigs with european-type prrsv. it was shown that three ... | 2010 | 20712485 |
| interleukin-10 antisense oligodeoxynucleotide suppresses il-10 expression and effects on proinflammatory cytokine responses to porcine reproductive and respiratory syndrome virus. | upregulation of interleukin-10 (il-10) expression has been suggested to be the mechanism by which the porcine reproductive and respiratory syndrome virus (prrsv) suppresses the innate and adaptive immune response in infected pigs. in this study we evaluated the potential of phosphorothioate-modified il-10 antisense oligodeoxynucleotide specific to the translation initiation region of porcine il-10 mrna (il-10as) in enhancing proinflammatory cytokine responses to prrsv. naïve peripheral blood mon ... | 2010 | 20712487 |
| priproet based melting point analyses on prrsv positive field samples. | a one-step real time rt-pcr method has previously been developed for the simultaneous detection of both genotypes of porcine reproductive and respiratory syndrome virus (prrsv). for further evaluation of the assay and a detailed characterization of the probe binding sites a collection of 24 prrsv positive field samples from hungary, serbia, austria, a highly pathogenic strain from bhutan and commercially available mlv vaccine strains were collected and sequenced from the terminal part of orf6 to ... | 2010 | 20713151 |
| immunisation of pigs with a major envelope protein sub-unit vaccine against porcine reproductive and respiratory syndrome virus (prrsv) results in enhanced clinical disease following experimental challenge. | disease exacerbation was observed in pigs challenged with virulent porcine reproductive and respiratory syndrome virus (prrsv) following immunisation with a recombinant gp5 sub-unit prrsv vaccine (rgp5) produced in e. coli. eighteen animals were divided into three experimental groups: group a were immunised twice im with rgp5, 21days apart; group b acted as positive controls (challenged but not immunised); and group c were negative controls. pigs in groups a and b were challenged 21days after th ... | 2010 | 20713312 |
| baculovirus expression of cloned porcine arterivirus generates infectious particles in both insect and mammalian cells. | studies on several viral pathogens have been hampered by the lack of appropriate in vitro systems for their propagation and amplification. porcine reproductive and respiratory syndrome virus (prrsv), an arterivirus containing a single-stranded positive-sense rna genome (∼15kb), was served as a model virus and its genomic cdna was recombinated into baculovirus. we investigated whether infectious virus particles could be generated by expression of the full-length cloned genome from the modified ba ... | 2010 | 20728481 |
| porcine reproductive and respiratory syndrome virus inhibits type i interferon signaling by blocking stat1/stat2 nuclear translocation. | type i interferons (ifns) ifn-α/β play an important role in innate immunity against viral infections by inducing antiviral responses. porcine reproductive and respiratory syndrome virus (prrsv) inhibits the synthesis of type i ifns. however, whether prrsv can inhibit ifn signaling is less well understood. in the present study, we found that prrsv interferes with the ifn signaling pathway. the transcript levels of ifn-stimulated genes isg15 and isg56 and protein level of signal transducer and act ... | 2010 | 20739522 |
| the ever-expanding diversity of porcine reproductive and respiratory syndrome virus. | porcine reproductive and respiratory syndrome (prrs) virus appeared 20 years ago as the cause of a new disease in swine. today prrs is the most significant swine disease worldwide in spite of intensive immunological interventions. the virus showed remarkable genetic variation with two geographically distinct genotypes at the time of its discovery, indicating the possibility of prolonged evolutionary divergence prior to its appearance as a swine pathogen. since then, both type 1 and type 2 have s ... | 2010 | 20801173 |
| the cysteine protease domain of porcine reproductive and respiratory syndrome virus non-structural protein 2 antagonizes interferon regulatory factor 3 activation. | there is growing evidence that porcine reproductive and respiratory syndrome virus (prrsv) has developed mechanisms to subvert the host innate immune response. prrsv non-structural protein 2 (nsp2) was suggested previously as a potential interferon (ifn) antagonist. this study focused on nsp2 to investigate its inhibitory mechanism of ifn induction. it was demonstrated that nsp2 strongly inhibited ifn-β production by antagonizing activation of the ifn regulatory factor 3 (irf-3) pathway induced ... | 2010 | 20826620 |
| marked differences between marc-145 cells and swine alveolar macrophages in ifnβ-induced activation of antiviral state against prrsv. | the activation of antiviral activity induced by recombinant swine interferon beta (rswifnβ) against prrsv was comparatively examined in marc-145 cells and porcine alveolar macrophages (pams). a dose-response analysis showed, in marc-145 cells, that isolate mo25544 was highly sensitive to rswifnβ while a vaccine strain and isolate pdv130-9301 were resistant to different extents. in contrast, all three viruses were equally sensitive to rswifnβ in pams even at the lowest dose of ifn utilized in the ... | 2011 | 20832126 |
| the interaction between prrsv and the late gestation pig fetus. | porcine reproductive and respiratory syndrome virus (prrsv) crosses the placenta during late gestation and productively infects the fetus. virus replication and cytokine responses were measured in tissues of fetuses recovered at 109-112 days of gestation, just prior to parturition. at the time of recovery, gross anatomical abnormalities were evident in both infected and non-infected fetuses from the infected dams. virus isolation and immunohistochemistry identified the thymus as the primary site ... | 2010 | 20832434 |
| identification of dispensable nucleotide sequence in 3' untranslated region of porcine reproductive and respiratory syndrome virus. | the 3' untranslated region (utr) of porcine arterivirus genome plays a pivotal role for virus replication, yet the properties of 3' utr remain largely undefined. we conducted site-directed mutagenesis to the 3' utr of the type ii porcine reproductive and respiratory syndrome virus (prrsv). serial deletions of the 3' utr showed that at least 40 nucleotides immediately following the orf7 stop codon were dispensable for the viability of prrsv in cultured cells. we then constructed a chimeric prrsv ... | 2010 | 20833212 |
| gp4-specific neutralizing antibodies might be a driving force in prrsv evolution. | the structural envelope glycoprotein gp4 of european porcine reproductive and respiratory syndrome virus (prrsv) strains contains a highly variable neutralizing epitope that is susceptible to neutralizing antibody-mediated selective pressure in vitro. in this study, it was analyzed what happens with this neutralizing epitope during infection in vivo in the presence of neutralizing antibodies. a neutralizing antibody-mediated selective pressure was created in 30 pigs by vaccination prior to inocu ... | 2010 | 20837070 |