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1.
BMC Genomics ; 22(1): 177, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33711920

RESUMO

BACKGROUND: Long noncoding RNA (lncRNA) is highly associated with inflammatory response and virus-induced interferon production. By far the majority of studies have focused on the immune-related lncRNAs of mice and humans, but the function of lncRNAs in porcine immune cells are poorly understood. Porcine reproductive and respiratory syndrome virus (PRRSV) impairs local immune responses in the lungs of nursery and growing pigs, whereas the virus triggers the inflammatory responses. Porcine alveolar macrophage (PAM) is the primary target cell of PRRSV, thus PRRSV is used as an in vitro model of inflammation. Here, we profiled lncRNA and mRNA repertories from PRRSV-infected PAMs to explore the underlying mechanism of porcine lncRNAs in regulating host immune responses. RESULTS: In this study, a total of 350 annotated lncRNAs and 1792 novel lncRNAs in PAMs were identified through RNA-seq analysis. Among them 86 differentially expressed (DE) lncRNAs and 406 DE protein-coding mRNAs were identified upon PRRSV incubation. GO category and KEGG pathway enrichment analyses revealed that these DE lncRNAs and mRNAs were mainly involved in inflammation- and pathogen infection-induced pathways. The results of dynamic correlated expression networks between lncRNAs and their predicted target genes uncovered that numerous lncRNAs, such as XLOC-022175, XLOC-019295, and XLOC-017089, were correlated with innate immune genes. Further analysis validated that these three lncRNAs were positively correlated with their predicted target genes including CXCL2, IFI6, and CD163. This study suggests that porcine lncRNAs affect immune responses against PRRSV infection through regulating their target genes in PAMs. CONCLUSION: This study provides both transcriptomic and epigenetic status of porcine macrophages. In response to PRRSV infection, comprehensive DE lncRNAs and mRNAs were profiled from PAMs. Co-expression analysis demonstrated that lncRNAs are emerging as the important modulators of immune gene activities through their critical influence upon PRRSV infection in porcine macrophages.

2.
Sci China Life Sci ; 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33655434

RESUMO

African swine fever virus (ASFV) has been circulating in China for more than two years, and it is not clear whether the biological properties of the virus have changed. Here, we report on our surveillance of ASFVs in seven provinces of China, from June to December, 2020. A total of 22 viruses were isolated and characterized as genotype II ASFVs, with mutations, deletions, insertions, or short-fragment replacement occurring in all isolates compared with Pig/HLJ/2018 (HLJ/18), the earliest isolate in China. Eleven isolates had four different types of natural mutations or deletion in the EP402R gene and displayed a non-hemadsorbing (non-HAD) phenotype. Four isolates were tested for virulence in pigs; two were found to be as highly lethal as HLJ/18. However, two non-HAD isolates showed lower virulence but were highly transmissible; infection with 106 TCID50 dose was partially lethal and caused acute or sub-acute disease, whereas 103 TCID50 dose caused non-lethal, sub-acute or chronic disease, and persistent infection. The emergence of lower virulent natural mutants brings greater difficulty to the early diagnosis of ASF and creates new challenges for ASFV control.

3.
Res Vet Sci ; 136: 18-24, 2021 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-33578290

RESUMO

Torque teno sus virus (TTSuV) infection is common in China's pig herd. Although of uncertain pathogenicity, TTSuVs have been reported as a worsening factor of other porcine diseases, including porcine circovirus associated disease (PCVAD), porcine respiratory diseases complex (PRDC) or porcine dermatitis and nephropathy syndrome (PDNS). To better understand the genetic diversity in TTSuVs, the complete genomes of two newly emerged isolates, referred to as HeN1-A9 and HeN1-A11, collected from pig samples at a large-scale pig farm in China, were analyzed. Phylogenetic relationships of TTSuV sequences separated TTSuV1 and TTSuVk2a groups and divided TTSuV1 into two major subtypes, including TTSuV1a and TTSuV1b; HeN1-A9 and HeN1-A11 strains classified into the TTSuV1a subtype. Recombination analysis demonstrated HeN1-A9 and HeN1-A11 were generated via recombination in the overlapping ORF1/ORF3 region of TTSuV1a genome, which we report for the first time. Furthermore, we found that HeN1-A9 could be replicated in cultured MARC-145 cells for 18 passages. Our findings may be useful for elucidating the characteristics and epidemic status of TTSuVs in China.

4.
Vet Microbiol ; 246: 108727, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32605755

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV) causes a substantial economic loss to the swine industry. Recently, NADC34-like PRRSV was reported in the USA, China and Peru and consistently attributed to a large number of abortions in the clinic. In the USA, the pathogenicity of NADC34-like PRRSV in piglets is highly variable. However, the pathogenicity of NADC34-like PRRSV in China is unclear. In this study, an NADC34-like PRRSV strain, HLJDZD32-1901, was isolated in primary alveolar macrophage (PAM) cells from a sow blood sample collected from an abortive farm in China. HLJDZD32-1901, with no recombination, has a 100-aa deletion in the NSP2 protein corresponding to positions 328-427 in the VR2332 strain. Phylogenetic analysis based on open reading frame 5 (ORF5) indicated that HLJDZD32-1901 belongs to sublineage 1.5. Animal experiments showed that the weight loss of HLJDZD32-1901-infected piglets was significantly different from that of control piglets at 8-14 dpi. In addition, the challenge group had obvious histopathological lesions, including interstitial pneumonia and enlarged lymph nodes, and increased viremia and viral loads in three tissues. However, piglets in the challenge group had only mild clinical symptoms, with no death or fever. Our results showed that NADC34-like PRRSV HLJDZD32-1901 is a mildly pathogenic strain in piglets. However, we speculate that HLJDZD32-1901 may be a highly pathogenic strain in pregnant sows based on clinical morbidity.

5.
Environ Res ; 189: 109869, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32678731

RESUMO

Mine tailing dumps represent significant threats to ecological environments due to the presence of toxic substances. The present work investigated the relationship among microbial activity, the community, antibiotic resistance genes (ARGs) and trace metals in soil surrounding gold mine tailings. Using microbial metabolic activity and high-throughput sequencing analysis, we found the trace metals Cd and Hg could be main factors influencing the microbial community. According to bacterial co-occurrence pattern analysis, the effects of total cadmium and total mercury on bacterial diversity are potentially mediated by influencing bacteria community in the keystone module II. Additionally, most of metal-resistant bacteria belong to Actinobacteria and Proteobacteria, and the metal tolerance suggested to be linked with various functions including replication, recombination and repair, as well as inorganic ion transport and metabolism based on PICRUSt2 analysis. We also found that metals generated by mining activity may trigger the co-selection of antibiotic resistance in the phyla Actinobacteria and Proteobacteria due to co-resistance or cross resistance. Additionally, PLS-PM analysis revealed that metals could indirectly affect ARGs by influencing bacterial diversity in gold mining areas.

6.
Int J Mol Sci ; 21(9)2020 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-32365661

RESUMO

Bcl2-associated athanogene (BAG) 3, which is a chaperone-mediated selective autophagy protein, plays a pivotal role in modulating the life cycle of a wide variety of viruses. Both positive and negative modulations of viruses by BAG3 were reported. However, the effects of BAG3 on pseudorabies virus (PRV) remain unknown. To investigate whether BAG3 could modulate the PRV life cycle during a lytic infection, we first identified PRV protein UL56 (pUL56) as a novel BAG3 interactor by co-immunoprecipitation and co-localization analyses. The overexpression of pUL56 induced a significant degradation of BAG3 at protein level via the lysosome pathway. The C-terminal mutations of 181L/A, 185L/A, or 181L/A-185L/A in pUL56 resulted in a deficiency in pUL56-induced BAG3 degradation. In addition, the pUL56 C-terminal mutants that lost Golgi retention abrogated pUL56-induced BAG3 degradation, which indicates a Golgi retention-dependent manner. Strikingly, BAG3 was not observed to be degraded in either wild-type or UL56-deleted PRV infected cells as compared to mock infected ones, whereas the additional two adjacent BAG3 cleaved products were found in the infected cells in a species-specific manner. Overexpression of BAG3 significantly suppressed PRV proliferation, while knockdown of BAG3 resulted in increased viral yields in HEK293T cells. Thus, these data indicated a negative regulation role of BAG3 during PRV lytic infection. Collectively, our findings revealed a novel molecular mechanism on host protein degradation induced by PRV pUL56. Moreover, we identified BAG3 as a host restricted protein during PRV lytic infection in cells.

8.
Transbound Emerg Dis ; 67(4): 1730-1738, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32037673

RESUMO

Porcine respiratory and reproductive syndrome virus (PRRSV) causes an economically important disease affecting commercial pork production worldwide. NADC34-like PRRSV has had a strong impact on the U.S. and Peruvian pig industries in recent years and also emerged in northeastern China in 2017. However, the endemic status of NADC34-like PRRSV in China is unclear. In this study, we examined 650 tissue samples collected from 16 Provinces in China from 2018 to 2019. Six NADC34-like PRRSV strains were detected in samples from three Provinces, and the complete genomes of four of these strains were sequenced. Phylogenetic analysis showed that these novel PRRSV strains belong to sublineage 1.5 (or NADC34-like PRRSV), forming two groups in China. Sequence alignment suggested that these novel strains share the same 100-aa deletion in the Nsp2 protein that was identified in IA/2014/NADC34 isolated from the United States in 2014. Recombination analysis revealed that five of eight complete genome sequences are derived from recombination between IA/2014/NADC34 and ISU30 or NADC30. The number and distribution of NADC34-like PRRSVs is increasing in China. Importantly, compared with the currently endemic strain NADC30-like PRRSV, NADC34-like PRRSV has the potential to be an endemic strain in China. This study will help us understand the epidemic status of NADC34-like PRRSV in China and provide data for further monitoring this type of PRRSV in China.


Assuntos
Doenças Endêmicas/veterinária , Síndrome Respiratória e Reprodutiva Suína/epidemiologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/isolamento & purificação , Doenças dos Suínos/epidemiologia , Animais , Sequência de Bases , China/epidemiologia , Variação Genética , Genoma Viral/genética , Filogenia , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Recombinação Genética , Alinhamento de Sequência/veterinária , Suínos , Doenças dos Suínos/virologia , Sequenciamento Completo do Genoma/veterinária
9.
Viruses ; 12(1)2020 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-31906441

RESUMO

The transcription factor NF-κB plays a critical role in diverse biological processes. The NF-κB pathway can be activated by incoming pathogens and then stimulates both innate and adaptive immunity. However, many viruses have evolved corresponding strategies to balance NF-κB activation to benefit their replication. Pseudorabies virus (PRV) is an economically important pathogen that belongs to the alphaherpesvirus group. There is little information about PRV infection and NF-κB regulation. This study demonstrates for the first time that the UL24 protein could abrogate tumor necrosis factor alpha (TNF-α)-mediated NF-κB activation. An overexpression assay indicated that UL24 inhibits this pathway at or downstream of P65. Furthermore, co-immunoprecipitation analysis demonstrated that UL24 selectively interacts with P65. We demonstrated that UL24 could significantly degrade P65 by the proteasome pathway. For the first time, PRV UL24 was shown to play an important role in NF-κB evasion during PRV infection. This study expands our understanding that PRV can utilize its encoded protein UL24 to evade NF-κB signaling.

10.
Nano Lett ; 20(2): 1417-1427, 2020 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-31930919

RESUMO

Labeling viruses with high-photoluminescence quantum dots (QDs) for single virus tracking provides a visual tool to aid our understanding of viral infection mechanisms. However, efficiently labeling internal viral components without modifying the viral envelope and capsid remains a challenge, and existing strategies are not applicable to most viruses. Here, we have devised a strategy using the clustered regularly interspaced short palindromic repeats (CRISPR) imaging system to label the nucleic acids of Pseudorabies virus (PRV) with QDs. In this strategy, QDs were conjugated to viral nucleic acids with the help of nuclease-deactivated Cas9/gRNA complexes in the nuclei of living cells and then packaged into PRV during virion assembly. The processes of PRV-QD adsorption, cytoplasmic transport along microtubules, and nuclear entry were monitored in real time in both Vero and HeLa cells, demonstrating the utility and efficiency of the strategy in the study of viral infection.

11.
J Virol ; 94(6)2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-31896589

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV), an important pathogen that affects the pig industry, is a highly genetically diverse RNA virus. However, the phylogenetic and genomic recombination properties of this virus have not been completely elucidated. In this study, comparative analyses of all available genomic sequences of North American (NA)-type PRRSVs (n = 355, including 138 PRRSV genomes sequenced in this study) in China and the United States during 2014-2018 revealed a high frequency of interlineage recombination hot spots in nonstructural protein 9 (NSP9) and the GP2 to GP3 regions. Lineage 1 (L1) PRRSV was found to be susceptible to recombination among PRRSVs both in China and the United States. The recombinant major parent between the 1991-2013 data and the 2014-2018 data showed a trend from complex to simple. The major recombination pattern changed from an L8 to L1 backbone during 2014-2018 for Chinese PRRSVs, whereas L1 was always the major backbone for US PRRSVs. Intralineage recombination hot spots were not as concentrated as interlineage recombination hot spots. In the two main clades with differential diversity in L1, NADC30-like PRRSVs are undergoing a decrease in population genetic diversity, NADC34-like PRRSVs have been relatively stable in population genetic diversity for years. Systematic analyses of insertion and deletion (indel) polymorphisms of NSP2 divided PRRSVs into 25 patterns, which could generate novel references for the classification of PRRSVs. The results of this study contribute to a deeper understanding of the recombination of PRRSVs and indicate the need for coordinated epidemiological investigations among countries.IMPORTANCE Porcine reproductive and respiratory syndrome (PRRS) is one of the most significant swine diseases. However, the phylogenetic and genomic recombination properties of the PRRS virus (PRRSV) have not been completely elucidated. In this study, we systematically compared differences in the lineage distribution, recombination, NSP2 polymorphisms, and evolutionary dynamics between North American (NA)-type PRRSVs in China and in the United States. Strikingly, we found high frequency of interlineage recombination hot spots in nonstructural protein 9 (NSP9) and in the GP2 to GP3 region. Also, intralineage recombination hot spots were scattered across the genome between Chinese and US strains. Furthermore, we proposed novel methods based on NSP2 indel patterns for the classification of PRRSVs. Evolutionary dynamics analysis revealed that NADC30-like PRRSVs are undergoing a decrease in population genetic diversity, suggesting that a dominant population may occur and cause an outbreak. Our findings offer important insights into the recombination of PRRSVs and suggest the need for coordinated international epidemiological investigations.


Assuntos
Polimorfismo Genético , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Recombinação Genética , Proteínas Virais/genética , Animais , China/epidemiologia , Filogeografia , Síndrome Respiratória e Reprodutiva Suína/epidemiologia , Síndrome Respiratória e Reprodutiva Suína/genética , Suínos , Estados Unidos/epidemiologia
12.
J Hazard Mater ; 383: 121136, 2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-31525690

RESUMO

The migration of metals (e.g., Fe, Cd, Co, Cr, Cu, Mn, Ni, and Zn) in both of iron tailings under different pH leachates was studied by laboratory static leaching experiments. The results indicated that Fe showed the highest leaching concentration at an initial pH of 2, reaching 16.19 and 51.72 mg L-1 in the Qian'anling (Q0) and Majuanzi (M0) iron tailings, respectively. Metal ions manifested a strong pH dependence. In addition, the leaching behavior of Cd, Cr, Fe, and Cu for the two tailings was also evaluated under leaching by three low-molecular-weight organic acids (LMWOAs). The results indicated the leaching of Cd and Fe followed the order of citric acid > malic acid > oxalic acid and that the leaching order for Cr and Cu was citric acid > oxalic acid > malic acid. The concentration of Fe was low in 5 mM oxalic acid leaching for 20 days because of the hydrolysis precipitation of iron ions and the complexation with organic ligand. The crystal lattice on the tailings was significantly damaged after leaching. The CO32- peak appeared in M0 with different treatments, and the proportion of COO- fitting peak areas increased markedly after leaching with LMWOAs.

13.
Sci Total Environ ; 707: 136116, 2020 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-31874394

RESUMO

Some metallic tailings from closed mines were scattered in upstream of the Miyun Reservoir, Beijing, threatening the ecological environment of rivers due to trace metals. The Liuli River, one of the main rivers affected, was investigated as a typical model in this work. In this study, we selected eight sites to assess interactions among the various geochemical factors especially between trace metals and sediment microbiota. Random forest predicted that low concentrations of Cu, Cd, Cr and Ni (lower than 61.8 mg/kg, 3.2 mg/kg, 173.2 mg/kg and 34.1 mg/kg, respectively) were able to enhance community diversity but generally, trace metals contamination impaired microbial diversity. Environmental factor correlation analysis showed that As, pH and available P were the major factors that shifted the distribution of the microbial communities. Metagenome sequencing revealed that Proteobacteria harbored the vast majority of heavy metal resistance genes followed by Actinobacteria and Bacteroidetes. Metal tolerance of Proteobacteria were achieved by exportation of metals by the corresponding transporters, by pumps and ion channels, or by their reduction via redox reactions. In addition, Proteobacteria harbored a greater ability to repair DNA damage via DNA recombination.


Assuntos
Microbiota , Pequim , Monitoramento Ambiental , Sedimentos Geológicos , Metagenoma , Metais Pesados , Rios , Poluentes Químicos da Água
14.
Emerg Microbes Infect ; 8(1): 1501-1510, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31631782

RESUMO

As one of many nonstructural proteins of porcine reproductive and respiratory syndrome virus (PRRSV), nonstructural protein 12 (Nsp12) has received relatively little attention, and its role in virus replication, if any, is essentially unknown. By the application of reverse genetic manipulation of an infectious PRRSV clone, the current study is the first to demonstrate that Nsp12 is a key component of PRRSV replication. In addition, the biochemical properties of Nsp12 were evaluated, revealing that Nsp12 forms dimers when exposed to oxidative conditions. Furthermore, we systemically analyzed the function of Nsp12 in PRRSV RNA synthesis using a strand-specific PCR method. To our surprise, Nsp12 was not found to be involved in minus-strand genomic RNA (-gRNA) synthesis; importantly, our results indicate that Nsp12 is involved in the synthesis of both plus- and minus-strand subgenomic mRNAs (+sgmRNA and -sgmRNA). Finally, we found that the combination of cysteine 35 and cysteine 79 in Nsp12 is required for sgmRNA synthesis. To our knowledge, we are the first to report the biological role of Nsp12 in the PRRSV lifecycle, and we conclude that Nsp12 is involved in the synthesis of both + sgRNA and -sgRNA.


Assuntos
Regulação Viral da Expressão Gênica , Vírus da Síndrome Respiratória e Reprodutiva Suína/metabolismo , RNA Mensageiro/genética , RNA Viral/genética , Proteínas não Estruturais Virais/metabolismo , Animais , Fases de Leitura Aberta , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , RNA Mensageiro/metabolismo , RNA Viral/metabolismo , Suínos , Transcrição Genética , Proteínas não Estruturais Virais/genética , Replicação Viral
15.
Viruses ; 11(10)2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31618847

RESUMO

Protein phosphatase 2A (PP2A), a major serine/threonine phosphatase in mammalian cells, is known to regulate the kinase-driven intracellular signaling pathways. Emerging evidences have shown that the PP2A phosphatase functions as a bona-fide therapeutic target for anticancer therapy, but it is unclear whether PP2A affects a porcine reproductive and respiratory syndrome virus infection. In the present study, we demonstrated for the first time that inhibition of PP2A activity by either inhibitor or small interfering RNA duplexes in target cells significantly reduced their susceptibility to porcine reproductive and respiratory syndrome virus (PRRSV) infection. Further analysis revealed that inhibition of PP2A function resulted in augmented production of type I interferon (IFN). The mechanism is that inhibition of PP2A activity enhances the levels of phosphorylated interferon regulatory factor 3, which activates the transcription of IFN-stimulated genes. Moreover, inhibition of PP2A activity mainly blocked PRRSV replication in the early stage of viral life cycle, after virus entry but before virus release. Using type I IFN receptor 2 specific siRNA in combination with PP2A inhibitor, we confirmed that the effect of PP2A on viral replication within target cells was an interferon-dependent manner. Taken together, these findings demonstrate that PP2A serves as a negative regulator of host cells antiviral responses and provides a novel therapeutic target for virus infection.


Assuntos
Interações entre Hospedeiro e Microrganismos , Fator Regulador 3 de Interferon/genética , Interferon Tipo I/imunologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Proteína Fosfatase 2/genética , Replicação Viral , Animais , Células Cultivadas , Fator Regulador 3 de Interferon/imunologia , Macrófagos Alveolares/virologia , Ácido Okadáico/farmacologia , Fosforilação , Proteína Fosfatase 2/antagonistas & inibidores , RNA Interferente Pequeno , Transdução de Sinais , Suínos
16.
Transbound Emerg Dis ; 66(6): 2592-2600, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31379138

RESUMO

Porcine reproductive and respiratory syndrome virus (PRRSV) is an agent of porcine reproductive and respiratory syndrome (PRRS), which causes substantial economic losses to the swine industry. PRRSV displays rapid variation, and five lineages coexist in mainland China. Lineage 3 PRRSVs emerged in mainland China in 2005 and prevailed in southern China after 2010. In the present study, two lineage 3 PRRSV strains, which are named SD110-1608 and SDWH27-1710, were isolated from northern China in 2017. To explore the characteristics and origins of the two strains, we divided lineage 3 into five sublineages (3.1-3.5) based on 146 open reading frame (ORF) 5 sequences. Both strains and the strains isolated from mainland China were classified into sublineage 3.5. Lineage 3 PRRSVs isolated from Taiwan and Hong Kong were classified into sublineages 3.1-3.3 and sublineage 3.4, respectively. Recombination analysis revealed that SD110-1608 and SDWH27-1710 were derived from recombination of QYYZ (major parent strain) and JXA1 (minor parent strain). Sequence alignment showed that SD110-1608 and SDWH27-1710 shared a 36-aa insertion in Nsp2 with QYYZ isolated from Guangdong Province in 2010. Based on the evolutionary relationship among GP2a, GP3, GP4, GP5 and N proteins between sublineages 3.2 (FJ-1) and 3.5 (FJFS), we speculated that sublineage 3.5 (mainland China) originated from sublineage 3.2 (Taiwan, China). This study provides important information regarding the classification and transmission of lineage 3 PRRSVs.


Assuntos
Variação Genética , Genoma Viral , Vírus da Síndrome Respiratória e Reprodutiva Suína/classificação , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Recombinação Genética , Animais , China , Filogenia , Síndrome Respiratória e Reprodutiva Suína/virologia , Alinhamento de Sequência , Suínos
17.
J Mol Microbiol Biotechnol ; 29(1-6): 74-82, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32289779

RESUMO

Porcine reproductive and respiratory syndrome (PRRS), a serious disease of swine caused by the PRRS virus (PRRSV), had a severe economic impact worldwide. As commonly used PRRS vaccines, the attenuated or inactivated vaccines, provide unsatisfactory immune protection, a new PRRS vaccine is urgently needed. In this study, a part of the PRRSV ORF6 gene (from 253 to 519 bp) encoding the hydrophilic domain of PRRSV M protein was integrated into two Listeria strains via homologous recombination to generate two PRRS vaccine candidates, namely LI-M' and LM-ΔactAplcB-M'. Both candidate vaccines showed similar growth rate as their parent strains in culture media, but presented different bacterial loads in target organs. As the integrated heterogenous gene was not expressed, LM-ΔactAplcB-M' was excluded from the immunological test. In a mouse model, LI-M' provoked both CD4+ and CD8+ T cell-mediated immunity. In addition, LI-M' boosting dramatically enhanced CD8+ T cell-mediated immunity without affecting the response intensity of CD4+ T cell-mediated immunity. All of these data suggest that LI-M' is a promising PRRS vaccine candidate.

18.
Arch Virol ; 164(2): 401-411, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30353281

RESUMO

Different strains of porcine reproductive and respiratory syndrome virus (PRRSV) have emerged and circulated in different regions of mainland China since 1996, particularly after 2006. In 2012, NADC30-like PRRSV was first isolated in Henan Province. By 2016, it had spread to most provinces in China. In the present study, the whole genomes (excluding the poly(A) tails) of 13 newly emerged NADC30-like PRRSV strains were sequenced and analyzed. Furthermore, the pathogenicity of SD53-1603, one of the 13 PRRSV strains, was assessed. Phylogenetic analysis showed that these 13 newly emerged NADC30-like PRRSV strains, together with some reference strains, formed a new subgroup (subgroup 5), characterized by a predicted 131-amino-acid deletion in the nonstructural protein (NSP) 2. However, low levels of whole-genome similarity and a wide variety of recombination patterns complicated the classification of the NADC30-like PRRSV isolates. Interestingly, almost all of the recombination breakpoints found in these 13 PRRSV isolates and other NADC30-like PRRSV isolates occurred in genes encoding NSPs and/or minor structural proteins. In addition, piglets infected with the newly emerged NADC30-like strain SD53-1603 displayed clear clinical respiratory symptoms and underwent typical pathological changes. The findings may be useful for elucidating the characteristics and epidemic status of NADC30-like PRRSV in China.


Assuntos
Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/isolamento & purificação , Animais , China/epidemiologia , Genoma Viral , Filogenia , Síndrome Respiratória e Reprodutiva Suína/epidemiologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/classificação , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Recombinação Genética , Deleção de Sequência , Suínos , Proteínas não Estruturais Virais/genética
19.
Vet Res ; 49(1): 103, 2018 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-30290850

RESUMO

In the original publication of this article [1], the author found the brand of vimentin antibody was wrong in Fig. 3. The legend of Fig. 3, 'mouse anti-vimentin mAb (Cell Signaling Technology) at 4 °C overnight' should be 'mouse anti-vimentin mAb (Sigma-Aldrich) at 4 °C overnight'.

20.
Vet Microbiol ; 222: 105-108, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30080663

RESUMO

Porcine reproductive and respiratory syndrome viruses (PRRSVs) pose a serious threat to the porcine industry of China, and the importation of novel strain(s) makes it challenging to control these viruses. Several NADC30-like PRRSV outbreaks have occurred in mainland China since 2013. In the current study, we report two novel PRRSVs, designated LNWK96 and LNWK130, which belong to lineage 1 and are closely related to US strains with ORF5 restriction fragment length polymorphism (RFLP) 1-7-4. The two viruses had a 100-aa deletion in the nsp2 gene corresponding to positions 328-427 in the VR-2332 strain, which was consistent with most of the ORF5 RFLP 1-7-4 viruses. Recombination analyses indicated that both viruses derived from the recombination of 1-7-4 isolates and ISU30 or NADC30, which were isolated in the United States. Taken together, these results demonstrate the emergence of ORF5 RFLP 1-7-4-like (NADC34-like) PRRSVs in China for the first time.


Assuntos
Doenças Transmissíveis Importadas/veterinária , Surtos de Doenças/veterinária , Síndrome Respiratória e Reprodutiva Suína/epidemiologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Vírus da Síndrome Respiratória e Reprodutiva Suína/isolamento & purificação , Proteínas do Envelope Viral , Animais , China/epidemiologia , Mapeamento Cromossômico , Doenças Transmissíveis Importadas/epidemiologia , Doenças Transmissíveis Importadas/transmissão , Doenças Transmissíveis Importadas/virologia , Fazendas , Variação Genética , Genoma Viral , Filogenia , Polimorfismo de Fragmento de Restrição/genética , Síndrome Respiratória e Reprodutiva Suína/virologia , Análise de Sequência de DNA , Deleção de Sequência , Suínos/virologia , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/transmissão , Doenças dos Suínos/virologia , Estados Unidos/epidemiologia , Proteínas do Envelope Viral/genética
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