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1.
Elife ; 92020 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-32876563

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV) and transmissible gastroenteritis virus (TGEV) are two highly infectious and lethal viruses causing major economic losses to pig production. Here, we report generation of double-gene-knockout (DKO) pigs harboring edited knockout alleles for known receptor proteins CD163 and pAPN and show that DKO pigs are completely resistant to genotype 2 PRRSV and TGEV. We found no differences in meat-production or reproductive-performance traits between wild-type and DKO pigs, but detected increased iron in DKO muscle. Additional infection challenge experiments showed that DKO pigs exhibited decreased susceptibility to porcine deltacoronavirus (PDCoV), thus offering unprecedented in vivo evidence of pAPN as one of PDCoV receptors. Beyond showing that multiple gene edits can be combined in a livestock animal to achieve simultaneous resistance to two major viruses, our study introduces a valuable model for investigating infection mechanisms of porcine pathogenic viruses that exploit pAPN or CD163 for entry.


Assuntos
Antígenos CD13/deficiência , Infecções por Coronavirus/prevenção & controle , Coronavirus/patogenicidade , Gastroenterite Suína Transmissível/prevenção & controle , Síndrome Respiratória e Reprodutiva Suína/prevenção & controle , Vírus da Síndrome Respiratória e Reprodutiva Suína/patogenicidade , Receptores de Superfície Celular/deficiência , Vírus da Gastroenterite Transmissível/patogenicidade , Animais , Animais Geneticamente Modificados , Antígenos CD/genética , Antígenos CD/imunologia , Antígenos de Diferenciação Mielomonocítica/genética , Antígenos de Diferenciação Mielomonocítica/imunologia , Composição Corporal , Antígenos CD13/genética , Antígenos CD13/imunologia , Coronavirus/imunologia , Infecções por Coronavirus/genética , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Suscetibilidade a Doenças , Gastroenterite Suína Transmissível/genética , Gastroenterite Suína Transmissível/imunologia , Gastroenterite Suína Transmissível/virologia , Técnicas de Silenciamento de Genes , Interações entre Hospedeiro e Microrganismos , Indústria de Embalagem de Carne , Fenótipo , Síndrome Respiratória e Reprodutiva Suína/genética , Síndrome Respiratória e Reprodutiva Suína/imunologia , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/imunologia , Sus scrofa/genética , Suínos , Vírus da Gastroenterite Transmissível/imunologia , Ganho de Peso
2.
Arch Virol ; 165(10): 2259-2277, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32699981

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV) is a widely disseminated, macrophage-tropic arterivirus that exhibits profound genetic and pathogenic heterogeneity. The present study was conducted to determine the complete genome sequences of two novel Korean lineage 1 PRRSV-2 strains, KNU-1901 and KNU-1902, which were isolated from vaccinated pig farms experiencing unusually high morbidity and mortality. Both isolates contained notable discontinuous 423-nucleotide deletions (DELs) within the genes encoding nonstructural protein 2 (nsp2) and GP3 when compared with the prototype strain VR-2332. In particular, the nsp2 DEL viruses had unique quadripartite discontinuous DEL signatures (111-1-19-9) in nsp2; this is an expanded version of the tripartite 111-1-19 DEL previously identified in virulent lineage 1 PRRSV-2 strains. Phylogenetic analysis revealed that both novel nsp2 DEL viruses belong to the Korean clade (KOR C) of lineage 1 isolates based on ORF5 but cluster with lineage KOR A strains based on the nsp2 or complete genome sequence. Recombination detection analysis suggested that both novel isolates are recombinants and may have evolved via natural inter-lineage recombination between circulating KOR A and KOR C strains. Interestingly, compared with the prototype VR-2332 virus, the novel nsp2 DEL variants were less efficient at promoting the expression of immune response genes in porcine alveolar macrophage culture. Taken together, we conclude that KNU-1901 and KNU-1902 are recently evolved recombinant variants of the virulent lineage 1 family that caused the regional severe PRRS outbreaks.


Assuntos
Citocinas/genética , Genoma Viral , Filogenia , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Vírus da Síndrome Respiratória e Reprodutiva Suína/patogenicidade , Proteínas não Estruturais Virais/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular Transformada , Citocinas/imunologia , Evolução Molecular , Expressão Gênica , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/virologia , Fases de Leitura Aberta , Síndrome Respiratória e Reprodutiva Suína/epidemiologia , Síndrome Respiratória e Reprodutiva Suína/imunologia , Síndrome Respiratória e Reprodutiva Suína/patologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/classificação , Vírus da Síndrome Respiratória e Reprodutiva Suína/isolamento & purificação , Recombinação Genética , República da Coreia/epidemiologia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Suínos , Virulência
3.
Arch Virol ; 165(8): 1803-1813, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32474688

RESUMO

In recent years, the availability of reverse genetics systems for porcine reproductive and respiratory syndrome virus (PRRSV) has created new perspectives for the use of recombinant viruses as expression vectors. Most of these recombinant PRRSV vectors express foreign genes through either an independent transcription unit inserted in ORF1b and ORF2, or in ORF7 and the 3' UTR. The aim of this study was to find an alternative site for foreign gene insertion into the PRRSV genome. Here, we constructed an infectious cDNA clone for a cell-adapted PRRSV strain, GXNN1396-P96. This cDNA-clone-derived recombinant virus (rGXAM) was comparable in its growth kinetics in MARC-145 cells to the parental virus, GX1396-P96. Using the infectious cDNA-clone, we inserted an independent transcription unit in ORF4 and ORF5a to generate a novel PRRSV-based recombinant virus expressing the green fluorescent protein (GFP) gene. Biological characterization of the recombinant virus, rGX45BSTRS-GFP, showed that it maintained similar growth characteristics but produced fewer infectious virions than the parental PRRSV. These data demonstrate that the ORF4 and ORF5a site is able to tolerate the insertion of foreign genes.


Assuntos
Marcadores Genéticos/genética , Fases de Leitura Aberta/genética , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Animais , Linhagem Celular , Proteínas de Fluorescência Verde/genética , Suínos , Replicação Viral/genética
4.
Arch Virol ; 165(9): 2057-2063, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32594320

RESUMO

In order to investigate the genetic diversity of porcine reproductive and respiratory syndrome virus (PRRSV) strains currently circulating in the Republic of Ireland (ROI), the ORF5 gene from 17 field strains originating from four vaccinating commercial herds was sequenced and phylogenetically analysed. High genetic variability was observed between farms at the nucleotide (86.3-95.2%) and amino acid (85.5-96%) levels. Phylogenetic analysis confirmed that all field strains belonged to the European species (type 1) and clustered into three separate groups within the subtype 1 subgroup. This variation may pose challenges for diagnosis and prophylactic control of PRRSV through vaccination in the ROI.


Assuntos
Filogenia , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/classificação , Vírus da Síndrome Respiratória e Reprodutiva Suína/isolamento & purificação , Sequência de Aminoácidos , Animais , Variação Genética , Genótipo , Irlanda/epidemiologia , Fases de Leitura Aberta , Síndrome Respiratória e Reprodutiva Suína/epidemiologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Suínos , Proteínas do Envelope Viral/genética
5.
J Vet Sci ; 21(3): e36, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32476312

RESUMO

BACKGROUND: Pseudorabies, also known as Aujeszky's disease, is caused by the pseudorabies virus (PRV) and has been recognized as a critical disease affecting the pig industry and a wide range of animals around the world, resulting in great economic losses each year. Shandong province, one of the most vital food animal-breeding regions in China, has a very dense pig population, within which pseudorabies infections were detected in recent years. The data, however, on PRV epidemiology and coinfection rates of PRV with other major swine diseases is sparse. OBJECTIVES: This study aimed to investigate the PRV epidemiology in Shandong and analyze the current control measures. METHODS: In this study, a total number of 16,457 serum samples and 1,638 tissue samples, which were collected from 362 intensive pig farms (≥ 300 sows/farm) covered all cities in Shandong, were tested by performing enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR). RESULTS: Overall, 52.7% and 91.5% of the serum samples were positive for PRV-gE and -gB, respectively, based on ELISA results. In addition, 15.7% of the tissue samples were PCR positive for PRV. The coinfection rates of PRV with porcine circovirus type 2 (PCV2), porcine reproductive and respiratory syndrome virus, and classical swine fever virus were measured; coinfection with PCV2 was 35.0%, higher than those of the other two viruses. Macroscopic and microscopic lesions were observed in various tissues during histopathological examination. CONCLUSIONS: The results demonstrate the PRV prevalence and its coinfection rates in Shandong province and indicate that pseudorabies is endemic in pig farms in this region. This study provides epidemiological data that can be useful in the prevention and control of pseudorabies in Shandong, China.


Assuntos
Infecções por Circoviridae/veterinária , Peste Suína Clássica/epidemiologia , Coinfecção/veterinária , Herpesvirus Suídeo 1/fisiologia , Síndrome Respiratória e Reprodutiva Suína/epidemiologia , Pseudorraiva/epidemiologia , Doenças dos Suínos/epidemiologia , Animais , China/epidemiologia , Infecções por Circoviridae/epidemiologia , Infecções por Circoviridae/virologia , Circovirus/fisiologia , Peste Suína Clássica/virologia , Vírus da Febre Suína Clássica/fisiologia , Coinfecção/epidemiologia , Coinfecção/virologia , Feminino , Incidência , Masculino , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Prevalência , Pseudorraiva/virologia , Sus scrofa , Suínos , Doenças dos Suínos/virologia
6.
Virology ; 546: 79-87, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32452419

RESUMO

In a previous study, we have shown that highly-pathogenic PRRSV (HP-PRRSV) nonstructural protein 4 (nsp4) antagonizes type I IFN expression induced by poly(I:C). Here, we demonstrated that the mutation of Aspartic acid 185 (Asp185) impaired the ability of nsp4 to inhibit IFN-I production induced by poly(I:C). Subsequently, we verified that all the mutants at the residue 185, regardless of amino acid size (including Cys and Ser) and charge (including Glu and Lys), impaired nsp4 catalytic activity. However, when Asp185 in nsp4 was replaced by a similar structure amino acid Asparagine 185 (Asn185), nsp4 stayed but with a decreased protease activity. Importantly, the recombinant virus with Asn185 mutation in HP-PRRSV-nsp4 exhibited slower replication rate and higher ability to induce IFN-I expression compared with wild-type (wt) HP-PRRSV.


Assuntos
Ácido Aspártico/metabolismo , Interferon beta/metabolismo , Síndrome Respiratória e Reprodutiva Suína/metabolismo , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/metabolismo , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/metabolismo , Animais , Interações Hospedeiro-Patógeno , Interferon beta/genética , Síndrome Respiratória e Reprodutiva Suína/genética , Vírus da Síndrome Respiratória e Reprodutiva Suína/química , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Vírus da Síndrome Respiratória e Reprodutiva Suína/patogenicidade , Suínos , Proteínas não Estruturais Virais/genética , Virulência
7.
J Anim Sci ; 98(6)2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32379891

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV) is an economically important disease, and the ingestion of soy isoflavones (ISF) may benefit PRRSV-infected pigs due to demonstrated anti-inflammatory and antiviral properties. The objective of this study was to quantify the effects of ISF consumption on fecal microbiome characteristics at different timepoints across a disease challenge and determine whether any changes, if present, elude to potential biological mechanisms for previously observed performance benefits. In total, 96 weaned barrows were group-housed in a Biosafety Level-2 containment facility and allotted to one of three experimental treatments that were maintained throughout the study: noninfected pigs receiving an ISF-devoid control diet (NEG, n = 24) and infected pigs receiving either the control diet (POS, n = 36) or that supplemented with total ISF in excess of 1,600 mg/kg (ISF, n = 36). Following a 7-d adaptation, pigs were inoculated intranasally with either a sham-control (phosphate-buffered saline) or live PRRSV (1 × 105 median tissue culture infectious dose[TCID]50/mL, strain NADC20). Fecal samples were collected from 48 individual pigs at pre-infection (-2 d post-inoculation [DPI]), peak-infection (10 DPI), and post-infection (144 DPI) timepoints. Extracted DNA was used to quantify fecal microbiota profiles via 16S bacterial rRNA sequencing. Differences in bacterial communities among diet groups were evaluated with principal coordinate analysis and permutational multivariate analysis of variance using UniFrac distance matrices based on both unweighted and weighted UniFrac distances using QIIME 2. All other data were analyzed by one-way ANOVA performed on square root transformations using R. Across all timepoints, only a few differences were observed due to ISF alone mainly in lowly abundant genera. The most notable differences observed were decreased relative abundance of Actinobacteria at 144 DPI between noninfected and infected treatments (P < 0.05), which is consistent with various dysbioses observed in other disease models. Our findings indicate that the differences present were mainly due to PRRSV-infection alone and not strongly influenced by diet, which implies that previously observed performance benefits conferred by dietary ISF are not likely due to the changes in microbiome composition.


Assuntos
Isoflavonas/farmacologia , Microbiota/efeitos dos fármacos , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína , Soja/química , Doenças dos Suínos/virologia , Ração Animal/análise , Animais , Dieta , Suplementos Nutricionais/análise , Ingestão de Alimentos/efeitos dos fármacos , Fezes/microbiologia , Masculino , Síndrome Respiratória e Reprodutiva Suína/microbiologia , Suínos , Doenças dos Suínos/microbiologia
8.
Arch Virol ; 165(7): 1621-1632, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32409873

RESUMO

Porcine reproductive and respiratory syndrome virus 2 (PRRSV2) is a major threat to the global pig industry, particularly in China, the world's largest pig-rearing and pork-production country. Continuously monitoring the epidemiological and genetic characteristics of PRRSV epidemic strains is beneficial for prevention and control of infection. Previously, we reported the epidemiological and genetic characteristics of PRRSV2 in China from 2012 to 2016. Here, the epidemiological and genetic characteristics of PRRSV2 in China from 2017 to 2018 are reported. During these two years, we collected different types of porcine samples from 2428 pig farms in 27 provinces in China. Of the 7980 samples collected, 2080 (26.07%) were positive for PRRSV2 ORF5 by RT-PCR. The positive rate of PRRSV detection between different regions of China ranged from 8.12% to 29.33%, and from 7.96% to 55.50% between different months. Phylogenetic analysis based on the ORF5 gene revealed that the PRRSV2 strains currently circulating in China belong to five clades, and most of the PRRSVs detected are highly pathogenic PRRSVs (HP-PRRSVs; clade IV) and PRRSV NADC30-like strains (clade I). Sequence analysis revealed multiple amino acid mutation types, including amino acid changes and deletions in both the GP5 and Nsp2 proteins. The presence of these mutations may have an effect on the evolution of the virus by altering the viral titer and/or affecting the antibody response against the virus.


Assuntos
Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Vírus da Síndrome Respiratória e Reprodutiva Suína/isolamento & purificação , Sequência de Aminoácidos , Animais , China/epidemiologia , Variação Genética , Fases de Leitura Aberta , Filogenia , Síndrome Respiratória e Reprodutiva Suína/epidemiologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/química , Vírus da Síndrome Respiratória e Reprodutiva Suína/classificação , Alinhamento de Sequência , Suínos , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/genética
9.
Vet Res ; 51(1): 47, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32228691

RESUMO

To better understand the host response to porcine reproductive and respiratory virus-2 (PRRSV2) we evaluated circulating thyroid hormone and associated gene expression in a late gestation challenge model. Pregnant gilts were inoculated at gestation day 85 and fetal samples collected at either 12 or 21 days post-infection (dpi). A subset of fetuses was selected for analysis based on viability and viral load categorized as either uninfected-viable (UNIF), high viral load viable (HV-VIA) or high viral load meconium stained (HV-MEC) and were compared with gestational age matched controls (CON). In dams, circulating levels of total T3 and T4 decreased in the acute period following infection and rebounded by 21 dpi. A similar effect was observed in fetuses, but was largely restricted to HV-VIA and HV-MEC, with minimal decrease noted in UNIF relative to CON at 21 dpi. Gene expression in fetal heart at 12 dpi showed significant decompensatory transcription of thyroid hormone transporters (SLC16A2) and deiodinases (DIO2, DIO3), which was not observed in brain. Correspondingly, genes associated with cell cycle progression (CDK1,2,4) were downregulated in only the heart of highly infected fetuses, while expression of their inhibitor (CDKN1A) was upregulated in both tissues. Finally, expression of genes associated with cardiac stress including CAMKD and AGT were upregulated in the hearts of highly infected fetuses, and a shift in expression of MYH6 to MYH7 was observed in HV-MEC fetuses specifically. Collectively, the results suggest PRRSV2 infection causes a hypothyroid state that disproportionally impacts the fetal heart over the brain.


Assuntos
Síndrome Respiratória e Reprodutiva Suína/fisiopatologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Glândula Tireoide/fisiologia , Animais , Feminino , Doenças Fetais/fisiopatologia , Doenças Fetais/veterinária , Doenças Fetais/virologia , Exposição Materna , Síndrome Respiratória e Reprodutiva Suína/virologia , Suínos
10.
Res Vet Sci ; 131: 38-42, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32289611

RESUMO

High genetic diversity and limited cross-protection are two major reasons for ineffective control of porcine reproductive and respiratory syndrome virus (PRRSV) infection. Therefore, it's important to dynamically monitor the prevalence of PRRSV for adopting appropriate control strategy. In this study, we analyzed PRRSV infection by detecting 712 clinical samples collected from 2016 to 2019 in China. Totally 100 samples were detected as PRRSV positive, including 2 and 98 samples were infected with PRRSV1 and PRRSV2, respectively. In addition, two out of the 98 PRRSV2 positive samples were co-infected with two distinct viruses. ORF5-based phylogenetic analysis showed that JXA1-like HP-PRRSV2 (lineage 8) and NADC30-like PRRSV2 (lineage 1) isolates are currently predominant, but QYYZ-like PRRSV2, CH-1a-like PRRSV2 and PRRSV1 isolates also co-exist in Chinese swine herds. In addition, two commercial MLV-derived viruses (TJM-F92-like and JXA1-R-like) were frequently detected. GP5 alignment also detected insertion and deletion in the extravirion domain. Our study presents the up-to-date PRRSV infection status and highlights the high genetic diversity of PRRSV currently circulating in China.


Assuntos
Variação Genética , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Animais , China/epidemiologia , Filogenia , Síndrome Respiratória e Reprodutiva Suína/epidemiologia , Deleção de Sequência , Suínos
11.
J Vet Diagn Invest ; 32(3): 394-400, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32274974

RESUMO

We developed a model to predict the cyclic pattern of porcine reproductive and respiratory syndrome virus (PRRSV) RNA detection by reverse-transcription real-time PCR (RT-rtPCR) from 4 major swine-centric veterinary diagnostic laboratories (VDLs) in the United States and to use historical data to forecast the upcoming year's weekly percentage of positive submissions and issue outbreak signals when the pattern of detection was not as expected. Standardized submission data and test results were used. Historical data (2015-2017) composed of the weekly percentage of PCR-positive submissions were used to fit a cyclic robust regression model. The findings were used to forecast the expected weekly percentage of PCR-positive submissions, with a 95% confidence interval (CI), for 2018. During 2018, the proportion of PRRSV-positive submissions crossed 95% CI boundaries at week 2, 14-25, and 48. The relatively higher detection on week 2 and 48 were mostly from submissions containing samples from wean-to-market pigs, and for week 14-25 originated mostly from samples from adult/sow farms. There was a recurring yearly pattern of detection, wherein an increased proportion of PRRSV RNA detection in submissions originating from wean-to-finish farms was followed by increased detection in samples from adult/sow farms. Results from the model described herein confirm the seasonal cyclic pattern of PRRSV detection using test results consolidated from 4 VDLs. Wave crests occurred consistently during winter, and wave troughs occurred consistently during the summer months. Our model was able to correctly identify statistically significant outbreak signals in PRRSV RNA detection at 3 instances during 2018.


Assuntos
Surtos de Doenças/veterinária , Síndrome Respiratória e Reprodutiva Suína/epidemiologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Animais , Reação em Cadeia da Polimerase/veterinária , Síndrome Respiratória e Reprodutiva Suína/virologia , RNA Viral/análise , Estações do Ano , Suínos , Estados Unidos/epidemiologia
12.
Res Vet Sci ; 130: 68-72, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32146377

RESUMO

Modified-live virus (MLV) vaccines derived from highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) were wildly used in China, which resulted in the emergence of MLV-like strains in pigs. Previous studies demonstrated that secondary bacterial infection could enhance HP-PRRSV infection-mediated inflammatory responses, but it is unknown whether early bacterial infection could enhance the HP-PRRSV MLV-like infection-mediated pathological reaction. In this paper, to gain the evidence for infection of pigs with MLV-like strains in China, we firstly analyzed the genetic characterization of the HP-PRRSV MLV-like isolate (TJxq1701) and further evaluated whether the early Streptococcus suis infection synergizes HP-PRRSV MLV-like infection-mediated pathological reaction. Our results showed that the whole genome of TJxq1701 shared the highest homology with JXA1-P80 and a total of 16 amino acids residues unique to JXA1-P80 in ORF1a, ORF1b, GP2, GP3, GP4, and GP5 were found in the corresponding locations. The results of infection experiments in pigs revealed that TJxq1701 caused transitional fever, moderate respiratory clinical sign and microscopic lung lesions in piglets, but early infection with low virulence Streptococcus suis serotype 2 (SS2) exhibited seriously clinical signs, including high fever, anorexia, and respiratory distress, leading to 60% mortality within four weeks in comparison with alone infected group. Taken together, our findings reveal that early bacterial infection could enhance the HP-PRRSV MLV-like infection-mediated pathological reaction, which provide an important clue for understanding that streptococcus infection increases the pathogenicity of MLV-like virus and a new thought for prevention and control of PRRSV.


Assuntos
Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/patogenicidade , Infecções Estreptocócicas/veterinária , Streptococcus suis/fisiologia , Doenças dos Suínos/virologia , Animais , Sorogrupo , Infecções Estreptocócicas/microbiologia , Streptococcus suis/genética , Suínos , Doenças dos Suínos/microbiologia , Vacinas Atenuadas , Virulência
13.
Vet Res ; 51(1): 14, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32075688

RESUMO

Guanylate-binding proteins (GBP1 and GBP5) are known to be important for host resistance against porcine reproductive and respiratory syndrome virus (PRRSV) infection. In this study, the effects of polymorphisms in GBP1 (GBP1E2 and WUR) and GBP5 on host immune responses against PRRSV were investigated to elucidate the mechanisms governing increased resistance to this disease. Seventy-one pigs [pre-genotyped based on three SNP markers (GBP1E2, WUR, and GBP5)] were assigned to homozygous (n = 36) and heterozygous (n = 35) groups and challenged with the JA142 PRRSV strain. Another group of nineteen pigs was kept separately as a negative control group. Serum and peripheral blood mononuclear cells (PBMCs) were collected at 0, 3, 7, 14, 21 and 28 days post-challenge (dpc). Viremia and weight gain were measured in all pigs at each time point, and a flow cytometry analysis of PBMCs was performed to evaluate T cell activation. In addition, 15 pigs (5 pigs per homozygous, heterozygous and negative groups) were sacrificed at 3, 14 and 28 dpc, and the local T cell responses were evaluated in the lungs, bronchoalveolar lavage cells (BALc), lymph nodes and tonsils. The heterozygous pigs showed lower viral loads in the serum and lungs and higher weight gains than the homozygous pigs based on the area under the curve calculation. Consistently, compared with the homozygous pigs, the heterozygous pigs exhibited significantly higher levels of IFN-α in the serum, proliferation of various T cells (γδT, Th1, and Th17) in PBMCs and tissues, and cytotoxic T cells in the lungs and BALc. These results indicate that the higher resistance in the pigs heterozygous for the GBP1E2, WUR and GBP5 markers could be mediated by increased antiviral cytokine (IFN-α) production and T cell activation.


Assuntos
Resistência à Doença , Proteínas de Ligação ao GTP/genética , Polimorfismo Genético , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Animais , Feminino , Proteínas de Ligação ao GTP/metabolismo , Masculino , Suínos
14.
Vet Res ; 51(1): 18, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-32093750

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV) is a significant threat to the global swine industry. Porcine sialoadhesin (poSn) has been previously shown to mediate PRRSV attachment and internalization. In the current study, we report its unidentified role in antagonism of type I interferon (IFN) production during PRRSV infection. We determined that poSn facilitated PRRSV infection via inhibition of type I IFN transcription. Mechanistically, poSn interacted with a 12 kDa DNAX-activation protein (DAP12), which was dependent on residues 51-57 within DAP12 transmembrane domain (TMD). PRRSV exploited the poSn-DAP12 pathway to attenuate activation of nuclear factor-kappa B (NF-κB). More importantly, the poSn-DAP12 pathway was involved in inhibiting poly (I:C)-triggered IFN production. All these results reveal a novel role of poSn in suppressing host antiviral responses, which deepens our understanding of PRRSV pathogenesis.


Assuntos
Interferon Tipo I/metabolismo , Síndrome Respiratória e Reprodutiva Suína/metabolismo , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Lectina 1 Semelhante a Ig de Ligação ao Ácido Siálico/metabolismo , Animais , Antígenos de Diferenciação de Linfócitos T/metabolismo , NF-kappa B/metabolismo , Síndrome Respiratória e Reprodutiva Suína/virologia , Transdução de Sinais , Suínos
15.
Biomed Res Int ; 2020: 4045204, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32083129

RESUMO

Alternative splicing (AS) plays a significant role in regulating gene expression at the transcriptional level in eukaryotes. Flexibility and diversity of transcriptome and proteome can be significantly increased through alternative splicing of genes. In the present study, transcriptome data of peripheral immune organs including spleen and inguinal lymph nodes (ILN) were used to identify AS difference between PRRSV-resistant Tongcheng (TC) pigs and PRRSV-susceptible Large White (LW) pigs artificially infected with porcine reproductive and respiratory syndrome virus (PRRSV) in vivo. The results showed that PRRSV infection induced global alternative splicing events (ASEs) with different modes. Among them, 373 genes and 595 genes in the spleen and ILN of TC pigs, while 458 genes and 560 genes in the spleen and ILN of LW pigs had significantly differential ASEs. Alternative splicing was subject to tissue-specific and lineage-specific regulation in response to PRRSV infection. Enriched GO terms and pathways showed that genes with differential ASEs played important roles in transcriptional regulation, immune response, metabolism, and apoptosis. Furthermore, a splicing factor associated with apoptosis, SRSF4, was significantly upregulated in LW pigs. Functional analysis on apoptosis associated genes was validated by RT-PCR and DNA sequencing. These findings revealed different response to PRRSV between PRRSV-resistant TC pigs and PRRSV-susceptible LW pigs at the level of alternative splicing, suggesting the potential relationship between AS and disease resistance to PRRSV.


Assuntos
Processamento Alternativo/genética , Síndrome Respiratória e Reprodutiva Suína/genética , Vírus da Síndrome Respiratória e Reprodutiva Suína/patogenicidade , Animais , Apoptose/genética , Resistência à Doença/genética , Perfilação da Expressão Gênica/métodos , Linfonodos/virologia , Síndrome Respiratória e Reprodutiva Suína/virologia , Fatores de Processamento de Serina-Arginina/genética , Baço/virologia , Suínos , Transcriptoma/genética , Regulação para Cima/genética
16.
Transbound Emerg Dis ; 67(4): 1574-1584, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31975574

RESUMO

There are four major porcine reproductive and respiratory syndrome virus 2 (PRRSV2) lineages circulating in China based on classification system, including lineages 1 (NADC30-like), 3 (QYYZ-like), 5.1 (VR2332-like) and 8 (JXA1-like/CH-1a-Like), which leads to the potential recombination. In the present study, a novel variant of PRRSV2 strain named JS18-3 was isolated from piglets suffering severe breathing difficulties in Jiangsu Province of China in 2018. Full-length genome analysis indicated that JS18-3 shared 86.5%, 87.9%, 84.2%, 82.2% and 86.4% nucleotide similarity with PRRSVs CH-1a, JXA1, VR2332, QYYZ and NADC30, respectively. 4871-6635 of JS18-3 shared the highest identity of 99.3% in nucleotide sequence with HP-PRRSV representative strain JXA1 indicating ongoing evolution to HP-PRRSV. JS18-3 was classified into classical lineage 8 of PRRSV2 based on phylogenetic analysis of complete genome and ORF5. Genomic break points in structural (ORF3) and non-structural (NSP2, NSP3) regions of genomes were detected in recombination analysis. JS18-3 is a recombinant isolate from lineages 8, 1 and 3. Replication enhancement and severe cytopathic effects caused by JS18-3 were observed in Marc-145 cells and porcine alveolar macrophages (PAMs) as compared to JX07, a typical strain of lineage 8. Pathogenicity results indicated that piglets inoculated with JS18-3 presented persistent fever, dyspnoea, serious microscopic lung lesions and lymph node congestion. The study suggests that lineage 8 of PRRSV2 is involved in continuing evolution by genetic recombination and mutation leading to outbreaks in vaccinated pigs in China.


Assuntos
Genoma Viral/genética , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/isolamento & purificação , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Recombinação Genética , Doenças dos Suínos/virologia , Replicação Viral/fisiologia , Sequência de Aminoácidos , Animais , Sequência de Bases , China/epidemiologia , Efeito Citopatogênico Viral/fisiologia , Variação Genética , Genômica , Macrófagos Alveolares/virologia , Filogenia , Síndrome Respiratória e Reprodutiva Suína/epidemiologia , Suínos , Doenças dos Suínos/epidemiologia
17.
Virology ; 540: 172-183, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31928999

RESUMO

Two type 2 field porcine reproductive and respiratory syndrome viruses (PRRSV) isolated from PRRS-affected swine farms were attenuated by de-optimization of codon pair bias in NSP1. In 3-week-old pigs infection, the attenuated viruses showed significantly lower replication ability than the original viruses without distinct clinical sign and pathological lesions, which were observed in pig infected with the original viruses. Regarding induction of PRRSV specific immunity, the level of the neutralizing antibodies as well as secretion of IFN-γ-SCs in PBMCs was not different between the attenuated viruses and the original viruses. More importantly, pigs infected with the attenuated viruses exhibited significant reduction in respiratory scores, viremia, macroscopic and microscopic lung lesion scores, and PRRSV-antigen with interstitial pneumonia against a heterologous challenge with a type 2 virulent strain. Conclusively, the viruses attenuated by CPD in this study demonstrated potential usefulness as vaccine strains to provide protective immunity against diverse virulent PRRSVs.


Assuntos
Códon , Resistência à Doença/genética , Interações Hospedeiro-Patógeno/genética , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Proteínas não Estruturais Virais/genética , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Antígenos Virais/genética , Antígenos Virais/imunologia , Biologia Computacional/métodos , Genoma Viral , Instabilidade Genômica , Interações Hospedeiro-Patógeno/imunologia , Interferon gama , Testes de Neutralização , Filogenia , Síndrome Respiratória e Reprodutiva Suína/imunologia , Síndrome Respiratória e Reprodutiva Suína/patologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/classificação , Suínos , Proteínas não Estruturais Virais/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/imunologia , Virulência , Replicação Viral
18.
PLoS One ; 15(1): e0227265, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31910236

RESUMO

Pathogen challenges are often accompanied by reductions in feed intake, making it difficult to differentiate impacts of reduced feed intake from impacts of pathogen on various response parameters. Therefore, the objective of this study was to determine the impact of Porcine Reproductive and Respiratory Syndrome virus (PRRSV) and feed intake on parameters of jejunal function and integrity in growing pigs. Twenty-four pigs (11.34 ± 1.54 kg BW) were randomly selected and allotted to 1 of 3 treatments (n = 8 pigs/treatment): 1) PRRSV naïve, ad libitum fed (Ad), 2) PRRSV-inoculated, ad libitum fed (PRRS+), and 3) PRRSV naïve, pair-fed to the PRRS+ pigs' daily feed intake (PF). At 17 days post inoculation, all pigs were euthanized and the jejunum was collected for analysis. At days post inoculation 17, PRRS+ and PF pigs had decreased (P < 0.05) transepithelial resistance compared with Ad pigs; whereas fluorescein isothiocyanate-dextran 4 kDa permeability was not different among treatments. Active glucose transport was increased (P < 0.05) in PRRS+ and PF pigs compared with Ad pigs. Brush border carbohydrase activity was reduced in PRRS+ pigs compared with PF pigs for lactase (55%; P = 0.015), sucrase (37%; P = 0.002), and maltase (30%; P = 0.015). For all three carbohydrases, Ad pigs had activities intermediate that of PRRS+ and PF pigs. The mRNA abundance of the tight junction proteins claudin 2, claudin 3, claudin 4, occludin, and zonula occludens-1 were reduced in PRRS+ pigs compared with Ad pigs; however, neither the total protein abundance nor the cellular compartmentalization of these tight junction proteins differed among treatments. Taken together, this study demonstrates that the changes that occur to intestinal epithelium structure, function, and integrity during a systemic PRRSV challenge can be partially explained by reductions in feed intake. Further, long term adaptation to PRRSV challenge and caloric restriction does reduce intestinal transepithelial resistance but does not appear to reduce the integrity of tight junction protein complexes.


Assuntos
Ingestão de Alimentos/fisiologia , Mucosa Intestinal/fisiopatologia , Jejuno/fisiopatologia , Síndrome Respiratória e Reprodutiva Suína/fisiopatologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/patogenicidade , Animais , Restrição Calórica , Interações Hospedeiro-Patógeno/fisiologia , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Jejuno/citologia , Jejuno/metabolismo , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/isolamento & purificação , Sus scrofa , Suínos , Proteínas de Junções Íntimas/metabolismo , Junções Íntimas/metabolismo
19.
J Anim Sci ; 98(2)2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31960037

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV) is an economically important disease, and ingestion of soy isoflavones (ISF) may benefit PRRSV-infected pigs due to demonstrated anti-inflammatory and antiviral properties. The objective of this experiment was to recreate immunological effects previously observed in young pigs infected with PRRSV receiving ISF and determine how those effects influence growth performance during the entire growth period from weaning to market. In total, 96 weaned barrows were group housed in a biosafety level-2 containment facility and allotted to 1 of 3 experimental treatments that were maintained throughout the study: noninfected pigs received an ISF-devoid control diet (NEG, n = 24), and infected pigs received either the control diet (POS, n = 36) or that supplemented with total ISF in excess of 1,600 mg/kg (ISF, n = 36). Following a 7-d adaptation, weanling pigs were inoculated intranasally with either a sham-control (PBS) or live PRRSV (1 × 105 TCID50/mL, strain NADC20). After inoculation, individual blood samples (n = 8 to 12/treatment) were routinely collected to monitor viral clearance and hematological parameters, including serum neutralizing anti-PRRSV antibody production. Pen-based oral fluids were used to monitor PRRSV clearance at later growth stages. A 1- or 2-way ANOVA was performed to compare experimental treatments depending on whether the outcome was repeatedly measured. In general, PRRSV infection decreased performance during early growth phases, resulting in 5.4% lower final BW for POS vs. NEG pigs (P < 0.05). Dietary ISF elicited inconsistent effects on growth performance, increased (P < 0.05) neutrophil cell counts and the relative proportion of memory T-cells, and decreased (P < 0.05) the time to full PRRSV clearance from oral fluids. Dietary ISF also elicited earlier, more robust anti-PRRSV neutralizing antibody production when compared with POS pigs. Additionally, and most notably, POS pigs experienced ~50% greater infection-related mortality rate vs. ISF pigs (P < 0.05), which may have significant economic implications for producers. Overall, dietary ISF ingestion supported immune responses and reduced mortality in PRRSV-infected pigs when fed to growing pigs though the biological mechanism of these effects remains unclear.


Assuntos
Suplementos Nutricionais/análise , Isoflavonas/administração & dosagem , Síndrome Respiratória e Reprodutiva Suína/tratamento farmacológico , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Soja/química , Ração Animal/análise , Animais , Anticorpos Antivirais/sangue , Dieta/veterinária , Ingestão de Alimentos , Masculino , Síndrome Respiratória e Reprodutiva Suína/imunologia , Síndrome Respiratória e Reprodutiva Suína/mortalidade , Síndrome Respiratória e Reprodutiva Suína/virologia , Suínos , Desmame
20.
Acta Vet Hung ; 67(4): 529-542, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31842600

RESUMO

Eradication of porcine reproductive and respiratory syndrome virus (PRRSV) from the pig population of Hungary started in 2014 on the basis of the territorial principle. In order to reach this goal it was crucial to render each fattening unit free of this disease, since fattening units play a significant role in spreading the virus all over the country. In 2015, 188 out of 307 large-scale fattening farms (61.2%) kept PRRS-positive animals. The main source of infection of these farms was the import of PRRS-infected fattening pigs. The following methods were used during the eradication from 2017: (1) Only pigs coming from PRRS-free farms were allowed to be used for fattening in Hungary; (2) Quarantine of all herds for 60 days; (3) PCR test for PRRS 48 hours after the arrival of the prefattening animals; (4) Serological test for PRRS at the end of the quarantine period. If any diagnostic test gave even one positive result and the result was confirmed by another test, the stock had to be sold for slaughter within 15 days or placed outside Hungary, so that the infected stock would not compromise the PRRS status of that area. PRRSV eradication on large-scale fattening units applying all-in/all-out operation was relatively simple, using the depopulation-repopulation method. On permanently operating farms, the infected herd was sold from time to time, without having to be repopulated until the last delivery. After cleaning, disinfection and restocking, the repopulation was done with PRRS-free animals. As the eradication progressed over the years, a ban on the import of infected fattening pigs was imposed. As a consequence of these measures, by the end of 2018, Hungarian large-scale fattening farms became free of PRRS. Maintaining the national-level PRRS-free status of large-scale pig fattening units contributes to eliminating a significant cost factor from the Hungarian pork production industry, and opens the way for a significant reduction in antibiotic consumption as well.


Assuntos
Criação de Animais Domésticos/métodos , Erradicação de Doenças/métodos , Síndrome Respiratória e Reprodutiva Suína/prevenção & controle , Animais , Hungria , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Suínos
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