Meclizine Inhibits Pseudorabies Virus Replication by Interfering With Virus Entry and Release

Pseudorabies virus (PRV) is a pathogen that causes substantial economic losses to the swine industry. With the emergence and widespread of PRV variants since 2011 in China, current commercial vaccines cannot provide complete protection against PRV infection. Therefore, antiviral drugs may work as an alternative way to control and prevent PRV. In this study, the inhibitory effects and underlying molecular mechanisms of meclizine against PRV were studied. Meclizine displayed a significant inhibitory effect against PRV when it was added before, simultaneously with, or after virus infection. The inhibitory effect of meclizine occurred during viral entry and cell-to-cell spreading but not at viral attachment into PK-15 cells. Meclizine also inhibited viral particle release at the late stage of infection. The antiviral effect of meclizine was tested in mice, and the results showed that meclizine reduced the severity of clinical symptoms and the viral loads in tissues, and delayed the death, after PRV challenge. The above results indicated that meclizine had an inhibitory effect on PRV. Our findings will contribute to the development of potential therapeutic drugs against PRV infection.

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Antiviral Effect of Resveratrol in Piglets Infected with Virulent Pseudorabies Virus

Viruses ◽

10.3390/v10090457 ◽

2018 ◽

Vol 10 (9) ◽

pp. 457 ◽

Cited By ~ 5

Author(s):

Xinghong Zhao ◽

Wenzhi Tong ◽

Xu Song ◽

Renyong Jia ◽

Lixia Li ◽

...

Keyword(s):

Pseudorabies Virus ◽

Control Measure ◽

Antiviral Effect ◽

Economic Losses ◽

Interleukin 12 ◽

Necrosis Factor Alpha ◽

Viral Loads ◽

Factor Alpha ◽

Potent Inhibitory Activity

Pseudorabies virus (PRV) is one of the most important pathogens of swine, resulting in devastating disease and economic losses worldwide. Nevertheless, there are currently no antiviral drugs available for PRV infection. Resveratrol (Res) was identified to exert its antiviral activity by inhibiting the PRV replication in preliminary investigations. In our previous study, we found that Res has anti-PRV activity in vitro. Here, we show that Res can effectively reduce the mortality and increase the growth performance of PRV-infected piglets. After Res treatment, the viral loads significantly (p < 0.001) decreased. Pathological symptoms, particularly inflammation in the brain caused by PRV infection, were significantly (p < 0.001) relieved by the effects of Res. In Res-treated groups, higher levels of cytokines in serum, including interferon gama, interleukin 12, tumor necrosis factor-alpha and interferon alpha were observed at 7 days post infection. These results indicated that Res possesses potent inhibitory activity against PRV-infection through inhibiting viral reproduction, alleviating PRV-induced inflammation and enhancing animal immunity, suggesting that Res is expected to be a new alternative control measure for PRV infection.

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Isatis root polysaccharide promotes maturation and secretory function of monocyte-derived dendritic cells

BMC Complementary Medicine and Therapies ◽

10.1186/s12906-020-03103-2 ◽

2020 ◽

Vol 20 (1) ◽

Author(s):

Xuebing Wang ◽

Zewen Chen ◽

Tong Chen ◽

Xiao Li ◽

Shucheng Huang ◽

...

Keyword(s):

Dendritic Cells ◽

Pseudorabies Virus ◽

Molecular Mechanisms ◽

Peripheral Blood Monocyte ◽

Economic Losses ◽

Enzyme Linked Immunosorbent Assay ◽

Swine Industry ◽

Chinese Medicinal Herb ◽

Animal Virus ◽

Immature Dendritic Cells

Abstract Background Pseudorabies virus (PRV) is an animal virus that is globally responsible for the high economic losses in the swine industry. Isatis root is a traditional Chinese medicinal herb that possesses immune-enhancing and antiviral properties. However, the molecular mechanisms underlying the effects of the active component of the isatis root polysaccharide (IRPS) extract on immature dendritic cells remain elusive. Methods In this study, we investigated the molecular changes in primary porcine peripheral blood monocyte-derived dendritic cells (MoDCs) during PRV infection, using enzyme-linked immunosorbent assay (ELISA) and quantitative reverse transcription-polymerase chain reaction. Additionally, we studied the effect of IRPS on PRV-infected DCs. Results The results showed that IRPS stimulated the maturation of MoDCs, induced IL-12 secretion, and downregulated IL-6 expression. Conclusions Collectively, these results suggest that IRPS is a promising candidate for promoting maturation of DCs and enhancing their secretory potential after PRV infection.

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Recombinant pseudorabies virus with gI/gE deletion generated by overlapping polymerase chain reaction and homologous recombination technology induces protection against the PRV variant PRV-GD2013

BMC Veterinary Research ◽

10.1186/s12917-021-02861-6 ◽

2021 ◽

Vol 17 (1) ◽

Author(s):

Wenhui Li ◽

Dijing Zhuang ◽

Hong Li ◽

Mengpo Zhao ◽

Erpeng Zhu ◽

...

Keyword(s):

Homologous Recombination ◽

Vaccine Strain ◽

Recombinant Virus ◽

Pseudorabies Virus ◽

Clinical Symptoms ◽

Growth Curves ◽

Economic Losses ◽

Plaque Morphology ◽

Swine Industry ◽

Antigenic Variant

Abstract Background Since 2011, numerous highly virulent and antigenic variant viral strains have been reported in pigs that were vaccinated against the swine pseudorabies virus. These infections have led to substantial economic losses in the Chinese swine industry. Results This study, constructed a novel recombinant vaccine strain with gI/gE deletion (PRV-GD2013-ΔgI/gE) by overlapping PCR and homologous recombination technology. The growth curves and plaque morphology of the recombinant virus were similar to those of the parental strain. However, PRV-GD2013-ΔgI/gE infection was significantly attenuated in mice compared with that of PRV-GD2013. Two-week-old piglets had normal rectal temperatures and displayed no clinical symptoms after being inoculated with 105 TCID50 PRV-GD2013-ΔgI/gE, indicating that the recombinant virus was avirulent in piglets. Piglets were immunized with different doses of PRV-GD2013-ΔgI/gE, or a single dose of Bartha-K61 or DMEM, and infected with PRV-GD2013 at 14 days post-vaccination. Piglets given high doses of PRV-GD2013-ΔgI/gE showed no obvious clinical symptoms, and their antibody levels were higher than those of other groups, indicating that the piglets were completely protected from PRV-GD2013. Conclusions The PRV-GD2013-ΔgI/gE vaccine strain could be effective for immunizing Chinese swine herds against the pseudorabies virus (PRV) strain.

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PRV UL13 inhibits cGAS–STING-mediated IFN-β production by phosphorylating IRF3

Veterinary Research ◽

10.1186/s13567-020-00843-4 ◽

2020 ◽

Vol 51 (1) ◽

Author(s):

Zongyi Bo ◽

Yurun Miao ◽

Rui Xi ◽

Qiuping Zhong ◽

Chenyi Bao ◽

...

Keyword(s):

Transcriptional Activation ◽

Pseudorabies Virus ◽

Nuclear Translocation ◽

Economic Loss ◽

Inhibitory Effect ◽

Poly I:C ◽

Interferon Response ◽

Type I ◽

Creb Binding Protein ◽

Swine Industry

Abstract Cyclic GMP-AMP (cGAMP) synthase (cGAS) is an intracellular sensor of cytoplasmic viral DNA created during virus infection, which subsequently activates the stimulator of interferon gene (STING)-dependent type I interferon response to eliminate pathogens. In contrast, viruses have developed different strategies to modulate this signalling pathway. Pseudorabies virus (PRV), an alphaherpesvirus, is the causative agent of Aujeszky’s disease (AD), a notable disease that causes substantial economic loss to the swine industry globally. Previous reports have shown that PRV infection induces cGAS-dependent IFN-β production, conversely hydrolysing cGAMP, a second messenger synthesized by cGAS, and attenuates PRV-induced IRF3 activation and IFN-β secretion. However, it is not clear whether PRV open reading frames (ORFs) modulate the cGAS–STING-IRF3 pathway. Here, 50 PRV ORFs were screened, showing that PRV UL13 serine/threonine kinase blocks the cGAS–STING-IRF3-, poly(I:C)- or VSV-mediated transcriptional activation of the IFN-β gene. Importantly, it was discovered that UL13 phosphorylates IRF3, and its kinase activity is indispensable for such an inhibitory effect. Moreover, UL13 does not affect IRF3 dimerization, nuclear translocation or association with CREB-binding protein (CBP) but attenuates the binding of IRF3 to the IRF3-responsive promoter. Consistent with this, it was discovered that UL13 inhibits the expression of multiple interferon-stimulated genes (ISGs) induced by cGAS–STING or poly(I:C). Finally, it was determined that PRV infection can activate IRF3 by recruiting it to the nucleus, and PRVΔUL13 mutants enhance the transactivation level of the IFN-β gene. Taken together, the data from the present study demonstrated that PRV UL13 inhibits cGAS–STING-mediated IFN-β production by phosphorylating IRF3.

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CRISPR/Cas9-based generation of a recombinant double-reporter pseudorabies virus and its characterization in vitro and in vivo

Veterinary Research ◽

10.1186/s13567-021-00964-4 ◽

2021 ◽

Vol 52 (1) ◽

Author(s):

Peng-Fei Fu ◽

Xuan Cheng ◽

Bing-Qian Su ◽

Li-Fang Duan ◽

Cong-Rong Wang ◽

...

Keyword(s):

Pseudorabies Virus ◽

Fluorescent Protein ◽

Antiviral Agents ◽

Firefly Luciferase ◽

Inhibitory Effect ◽

Economic Losses ◽

Green Fluorescent ◽

Swine Herds

AbstractPseudorabies, caused by pseudorabies virus (PRV) variants, has broken out among commercial PRV vaccine-immunized swine herds and resulted in major economic losses to the pig industry in China since late 2011. However, the mechanism of virulence enhancement of variant PRV is currently unclear. Here, a recombinant PRV (rPRV HN1201-EGFP-Luc) with stable expression of enhanced green fluorescent protein (EGFP) and firefly luciferase as a double reporter virus was constructed on the basis of the PRV variant HN1201 through CRISPR/Cas9 gene-editing technology coupled with two sgRNAs. The biological characteristics of the recombinant virus and its lethality to mice were similar to those of the parental strain and displayed a stable viral titre and luciferase activity through 20 passages. Moreover, bioluminescence signals were detected in mice at 12 h after rPRV HN1201-EGFP-Luc infection. Using the double reporter PRV, we also found that 25-hydroxycholesterol had a significant inhibitory effect on PRV both in vivo and in vitro. These results suggested that the double reporter PRV based on PRV variant HN1201 should be an excellent tool for basic virology studies and evaluating antiviral agents.

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The Function of the PRRSV–Host Interactions and Their Effects on Viral Replication and Propagation in Antiviral Strategies

Vaccines ◽

10.3390/vaccines9040364 ◽

2021 ◽

Vol 9 (4) ◽

pp. 364

Author(s):

Jun Ma ◽

Lulu Ma ◽

Meiting Yang ◽

Wei Wu ◽

Wenhai Feng ◽

...

Keyword(s):

Immune Response ◽

Molecular Mechanisms ◽

Immune Escape ◽

Rna Virus ◽

Economic Losses ◽

Respiratory Syndrome Virus ◽

Swine Industry ◽

Live Virus ◽

Virus Challenge ◽

Host Interactions

Porcine reproductive and respiratory syndrome virus (PRRSV) affects the global swine industry and causes disastrous economic losses each year. The genome of PRRSV is an enveloped single-stranded positive-sense RNA of approximately 15 kb. The PRRSV replicates primarily in alveolar macrophages of pig lungs and lymphatic organs and causes reproductive problems in sows and respiratory symptoms in piglets. To date, studies on how PRRSV survives in the host, the host immune response against viral infections, and pathogenesis, have been reported. PRRSV vaccines have been developed, including inactive virus, modified live virus, attenuated live vaccine, DNA vaccine, and immune adjuvant vaccines. However, there are certain problems with the durability and effectiveness of the licensed vaccines. Moreover, the high variability and fast-evolving populations of this RNA virus challenge the design of PRRSV vaccines, and thus effective vaccines against PRRSV have not been developed successfully. As is well known, viruses interact with the host to escape the host’s immune response and then replicate and propagate in the host, which is the key to virus survival. Here, we review the complex network and the mechanism of PRRSV–host interactions in the processes of virus infection. It is critical to develop novel antiviral strategies against PRRSV by studying these host–virus interactions and structures to better understand the molecular mechanisms of PRRSV immune escape.

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MicroRNA-376b-3p Promotes Porcine Reproductive and Respiratory Syndrome Virus Replication by Targeting Viral Restriction Factor TRIM22

Journal of Virology ◽

10.1128/jvi.01597-21 ◽

2021 ◽

Author(s):

Jing Chen ◽

Shijie Zhao ◽

Zhiying Cui ◽

Wen Li ◽

Pengli Xu ◽

...

Keyword(s):

Viral Infections ◽

Antiviral Effect ◽

Economic Losses ◽

Respiratory Syndrome Virus ◽

Restriction Factor ◽

Transcriptional Level ◽

Swine Industry ◽

Human Virus ◽

N Protein ◽

Novel Strategy

Porcine reproductive and respiratory syndrome virus is a major economically significant pathogen and has evolved several strategies to evade host's antiviral response and provide favorable conditions for survival. In the present study, we demonstrated that a host microRNA, miR-376b-3p, was upregulated by PRRSV infection through the viral components, nsp4 and nsp11, and miR-376b-3p can directly target tripartite motif-containing 22 (TRIM22) to impair its anti-PRRSV activity, thus facilitating the replication of PRRSV. Meanwhile, we found that TRIM22 induced degradation of the nucleocapsid protein (N) of PRRSV by interacting with N protein to inhibit PRRSV replication, and further study indicated that TRIM22 could enhance the activation of lysosomal pathway by interacting with LC3 to induce lysosomal degradation of N protein. In conclusion, PRRSV increased miR-376b-3p expression and hijacked the host miR-376b-3p to promote PRRSV replication by impairing the antiviral effect of TRIM22. Therefore, our finding outlines a novel strategy of immune evasion exerted by PRRSV, which is helpful for better understanding the pathogenesis of PRRSV. IMPORTANCE Porcine reproductive and respiratory syndrome virus (PRRSV) causes enormous economic losses each year in the swine industry worldwide. MicroRNAs (miRNAs) play important roles during viral infections via modulating the expression of viral or host genes at post-transcriptional level. TRIM22 has recently been identified as a key restriction factor that inhibited the replication of a number of human virus such as HIV, ECMV, HCV, HBV, IAV, and RSV. Here we showed that host miR-376b-3p could be up-regulated by PRRSV and functioned to impair the anti-PRRSV role of TRIM22 to facilitate PRRSV replication. Meanwhile, we found that TRIM22 inhibited the replication of PRRSV by interacting with viral N protein and accelerating its degradation through the lysosomal pathway. Collectively, the paper described a novel mechanism that PRRSV exploited the host miR-376b-3p to evade antiviral responses and provided a new insight into the study of virus-host interactions.

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Development of Dual Fluorescent Microsphere Immunological Assay for Detection of Pseudorabies Virus gE and gB IgG Antibodies

10.21203/rs.3.rs-24925/v1 ◽

2020 ◽

Author(s):

chihai ji ◽

Jingyu Wang ◽

Yuchen Zeng ◽

Haoming Pan ◽

Yingfang Wei ◽

...

Keyword(s):

Pseudorabies Virus ◽

High Specificity ◽

Antibody Detection ◽

Economic Losses ◽

Igg Antibodies ◽

Wild Type ◽

Swine Industry ◽

Igg Antibody ◽

Fluorescent Microsphere ◽

Specificity And Sensitivity

Abstract Background Pseudorabies, also known as Aujezsky’s disease, is an acute viral infection caused by pseudorabies virus (PRV). Swine are one of the natural hosts of pseudorabies, therefore, the disease brings huge economic losses to the swine industry. Establishment of a differential diagnosis technique that can distinguish between wild-type infected and vaccinated pigs, and monitor vaccine-induced IgG is crucial for eventual eradication of pseudorabies.Results The aim of this study was to develop a rapid dual detection method for PRV gE and gB protein IgG antibodies with high specificity and sensitivity. PRV gE codons at amino acid residues (aa) 52–238 and gB codons at aa 539–741 were expressed to obtain recombinant PRV gE and gB proteins by pMAL-c5x vector. After purification with Qiagen Ni–NTA agarose affinity, the two proteins were analyzed by SDS-PAGE and immunoblotting assay. Two single fluorescent-microsphere immunoassays (FMIA) were established by coupling two recombinant proteins (gE and gB) with two magnetic microbeads and an effective dual FMIA was developed by integrating the two single assays. Optimal serum dilution for each assay, correlation with other common swine virus-positive sera and comparison with ELISA for two PRV antigens were tested for validation. Compared with ELISA, the specificity and sensitivity were 99.26% and 92.3% for gE IgG antibody detection and 95.74% and 96.3% for gB IgG antibody detection by dual-FMIA.Conclusion We provide a new method for monitoring PRV protective antibody in vaccinated pigs and differentiating wild-type-PRV-infected from vaccinated pigs

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Molecular Serotyping and Resistance of Clinical Strains of Haemophilus (Glaesserella) Parasuis in Chinese Pig Farms From 2016 to 2018.

10.21203/rs.3.rs-149652/v1 ◽

2021 ◽

Author(s):

Jinjin Liu ◽

Long Guo ◽

Yi Yuan ◽

Wenbo Song ◽

Qianqian Li ◽

...

Keyword(s):

Large Scale ◽

Clinical Symptoms ◽

Inhibitory Effect ◽

Diffusion Method ◽

Economic Losses ◽

Clinical Samples ◽

Peptide Antibiotics ◽

Disk Diffusion Method ◽

Positive Role ◽

Pig Farms

Abstract Haemophilus parasuis (H. parasuis) is the etiological agent of Glässer's disease and brings great economic losses to the pig industry. The goal of our research is to reveal the serotypes of H. parasuis isolated from large-scale pig farms in China from 2016 to 2018. From 2016 to 2018, 8153 H. parasuis field strains were isolated from 14610 clinical samples of sick pigs with clinical symptoms from 26 provinces and cities of China. Among them, 1386 strains were identified as H. parasuis by PCR, and the isolation rate was 9.49%. Through multiplex PCR, we showed that type 5/12 and type 4 strains had the highest separation rate, followed by type 13 and type 14 strains. Using disk diffusion method, we found cephalosporin antibiotics and peptide antibiotics all had good inhibitory effect on H. parasuis. Our conclusion may play a positive role in the prevention and treatment of H. parasuis.

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Development of a droplet digital PCR for detection and quantification of porcine epidemic diarrhea virus

Journal of Veterinary Diagnostic Investigation ◽

10.1177/1040638720924753 ◽

2020 ◽

Vol 32 (4) ◽

pp. 572-576 ◽

Cited By ~ 1

Author(s):

Wei W. Cao ◽

Dong S. He ◽

Zhen J. Chen ◽

Yu Z. Zuo ◽

Xun Chen ◽

...

Keyword(s):

Porcine Epidemic Diarrhea Virus ◽

Fold Increase ◽

Digital Pcr ◽

Droplet Digital Pcr ◽

Economic Losses ◽

Swine Industry ◽

Diarrhea Virus ◽

Viral Loads ◽

Promising Tool ◽

Porcine Epidemic Diarrhea

Porcine epidemic diarrhea, a disease caused by porcine epidemic diarrhea virus (PEDV), results in large economic losses to the global swine industry. To manage this disease effectively, it is essential to detect PEDV early and accurately. We developed a sensitive and accurate droplet digital PCR (ddPCR) assay to detect PEDV. The optimal primer-to-probe concentration and melting temperature were identified as 300:200 nM and 59.2°C, respectively. The specificity of the ddPCR assay was confirmed by negative test results for common swine pathogens. The detection limit for the ddPCR was 0.26 copies/μL, which is a 5.7-fold increase in sensitivity compared to that of real-time PCR (rtPCR). Both ddPCR and rtPCR assays exhibited good linearity, although ddPCR provided higher sensitivity for clinical detection compared to that of rtPCR. Our ddPCR methodology provides a promising tool for evaluating the PEDV viral load when used for clinical testing, particularly for detecting samples with low-copy viral loads.

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