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IMPORTANCE: Rotavirus (RV) is an important zoonosis virus, which can cause severe diarrhea and extra-intestinal infection. To date, some proteins or carbohydrates have been shown to participate in the attachment or internalization of RV, including HGBAs, Hsc70, and integrins. This study attempted to indicate whether there were other proteins that would participate in the entry of RV; thus, the RV VP4-interacting proteins were identified by proximity labeling. After analysis and verification, it was found that VIM and ACTR2 could significantly promote the proliferation of RV in intestinal cells. Through further viral binding assays after knockdown, antibody blocking, and recombinant protein overexpression, it was revealed that both VIM and ACTR2 could promote RV replication.
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Proteína 2 Relacionada con la Actina , Proteínas de la Cápside , Mapas de Interacción de Proteínas , Rotavirus , Vimentina , Animales , Humanos , Proteína 2 Relacionada con la Actina/genética , Proteína 2 Relacionada con la Actina/metabolismo , Proteínas de la Cápside/metabolismo , Intestinos/citología , Rotavirus/química , Rotavirus/metabolismo , Vimentina/genética , Vimentina/metabolismo , Internalización del Virus , Replicación Viral , Unión ProteicaRESUMEN
Vaccination has proven effective against SARS-CoV-2 infection but vaccines were originally based on the wild type and emerging variants have led to a decrease in protective efficacy. There is an urgent need for broad-spectrum vaccine protection against emerging variants. A vaccine based on the Delta strain spike protein was created by optimization of vector, codon, and protein structure to produce a subunit immunogen (Delta-6P-S) containing six proline mutations, stable pre-fusion conformation, and with high expression in CHO-S cells. Immunogenicity and protective efficacy were evaluated in mice and golden hamsters using alum adjuvant. The Delta-6P-S recombinant protein induced strong immune responses in C57BL/6J mice and golden hamsters and sera had cross-neutralization activity and neutralized wild type and Beta, Delta, Omicron BA.1, BA.2, and BA.5 variant strains. Golden hamsters were immunized against Delta, Omicron BA.1, and BA.2 variants. Viral RNA detected from throat swabs, lungs and tracheas decreased significantly in vaccine-inoculated animals relative to alum-treated controls and no infectious viruses were detected in lungs and tracheas. Almost no pathological damage to lung tissue was found in vaccinated animals by contrast with those treated only with alum. The Delta-6P-S recombinant protein rapidly eliminated replicating virus in the upper and lower airways of golden hamsters and merits further investigation as a candidate anti-SARS-CoV-2 vaccine.
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COVID-19 , SARS-CoV-2 , Cricetinae , Animales , Ratones , Ratones Endogámicos C57BL , SARS-CoV-2/genética , COVID-19/prevención & control , Mesocricetus , Vacunas de Subunidad/genética , Proteínas Recombinantes/genética , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Glicoproteína de la Espiga del Coronavirus/genéticaRESUMEN
Breakthrough infections by SARS-CoV-2 variants pose a global challenge to COVID-19 pandemic control, and the development of more effective vaccines of broad-spectrum protection is needed. In this study, we constructed pVAX1-based plasmids encoding receptor-binding domain (RBD) chimera of SARS-CoV-1 and SARS-CoV-2 variants, including pAD1002 (encoding RBDSARS/BA1), pAD1003 (encoding RBDSARS/Beta) and pAD131 (encoding RBDBA1/Beta). Plasmids pAD1002 and pAD131 were far more immunogenic than pAD1003 in terms of eliciting RBD-specific IgG when intramuscularly administered without electroporation. Furthermore, dissolvable microneedle array patches (MAP) greatly enhanced the immunogenicity of these DNA constructs in mice and rabbits. MAP laden with pAD1002 (MAP-1002) significantly outperformed inactivated SARS-CoV-2 virus vaccine in inducing RBD-specific IFN-γ+ effector and memory T cells, and generated T lymphocytes of different homing patterns compared to that induced by electroporated DNA in mice. In consistence with the high titer neutralization results of MAP-1002 antisera against SARS-CoV-2 pseudoviruses, MAP-1002 protected human ACE2-transgenic mice from Omicron BA.1 challenge. Collectively, MAP-based DNA constructs encoding chimeric RBDs of SARS-CoV-1 and SARS-CoV-2 variants, as represented by MAP-1002, are potential COVID-19 vaccine candidates worthy further translational study.
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COVID-19 , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo , Vacunas de ADN , Animales , Humanos , Ratones , Conejos , Vacunas contra la COVID-19 , SARS-CoV-2 , Pandemias , ADN , Ratones Transgénicos , Anticuerpos Antivirales , Anticuerpos Neutralizantes , Glicoproteína de la Espiga del CoronavirusRESUMEN
Japanese encephalitis virus (JEV), which uses a mosquito primary vector and swine as a reservoir host, poses a significant risk to human and animal health. JEV can be detected in cattle, goats and dogs. A molecular epidemiological survey of JEV was conducted in 3105 mammals from five species, swine, fox, racoon dog, yak and goat, and 17,300 mosquitoes from 11 Chinese provinces. JEV was detected in pigs from Heilongjiang (12/328, 3.66%), Jilin (17/642, 2.65%), Shandong (14/832, 1.68%), Guangxi (8/278, 2.88%) and Inner Mongolia (9/952, 0.94%); in goats (1/51, 1.96%) from Tibet; and mosquitoes (6/131, 4.58%) from Yunnan. A total of 13 JEV envelope (E) gene sequences were amplified in pigs from Heilongjiang (5/13), Jilin (2/13) and Guangxi (6/13). Swine had the highest JEV infection rate of any animal species, and the highest infection rates were found in Heilongjiang. Phylogenetic analysis indicated that the predominant strain in Northern China was genotype I. Mutations were found at residues 76, 95, 123, 138, 244, 474 and 475 of E protein but all sequences had predicted glycosylation sites at 'N154. Three strains lacked the threonine 76 phosphorylation site from non-specific (unsp) and protein kinase G (PKG) site predictions; one lacked the threonine 186 phosphorylation site from protein kinase II (CKII) prediction; and one lacked the tyrosine 90 phosphorylation site from epidermal growth factor receptor (EGFR) prediction. The aim of the current study was to contribute to JEV prevention and control through the characterization of its molecular epidemiology and prediction of functional changes due to E-protein mutations.
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Culicidae , Virus de la Encefalitis Japonesa (Especie) , Virus de la Encefalitis Japonesa (Subgrupo) , Encefalitis Japonesa , Bovinos , Animales , Humanos , Porcinos , Perros , Virus de la Encefalitis Japonesa (Especie)/genética , Filogenia , China/epidemiología , Genotipo , Encefalitis Japonesa/epidemiología , Encefalitis Japonesa/veterinaria , Treonina/genética , MamíferosRESUMEN
The porcine reproductive and respiratory syndrome virus (PRRSV) is a threat to the health of pigs worldwide, but commercially available vaccines offer limited protection against PRRSV infection. It is necessary to develop a more effective DNA vaccine. The immunological effects of DNA vaccines with three adjuvants were examined in pigs (Susscrofa domestica) challenged with PRRSV. These DNA vaccines, which encoded PRRSV GP3 and GP5, were formulated with A1, A2, and A3. Serum specific and neutralizing antibodies, IL-4, IFN-γ, IL-2, IL-10, CD4+ and CD8+T-lymphocytes, health status, histopathology, and viral loads were determined. The results showed that the use of adjuvant A3 led to higher levels of neutralizing antibodies and a lower viral load in pigs compared to the other adjuvants. The neutralizing antibody titers of the pVAX-GP35+A1 and pVAX-GP35+A3 groups reached a peak of 1:19 at 35 dpi. The maximum concentration of IL-4 was 136.77 pg/mL in the pVAX-GP35+A3 group. At 35 dpi, the IFN-γ concentration in the pVAX-GP35+A1 group was 227.4 pg/mL. pVAX-GP35+A3 group shows the highest IL-2 and IL-10 expression to the peak of 597.6 pg/mL and 189.1 pg/mL, respectively. We found a formulation demonstrated beneficial immune outcomes. This study provides an alternative vaccine to protect pigs from PRRSV.
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Síndrome Respiratorio y de la Reproducción Porcina , Virus del Síndrome Respiratorio y Reproductivo Porcino , Vacunas de ADN , Vacunas Virales , Porcinos , Animales , Virus del Síndrome Respiratorio y Reproductivo Porcino/genética , Síndrome Respiratorio y de la Reproducción Porcina/prevención & control , Interleucina-10/genética , Interleucina-4 , Interleucina-2/genética , Anticuerpos Antivirales , Anticuerpos Neutralizantes , Adyuvantes Inmunológicos/farmacología , Recombinación Genética , Vacunas Virales/genéticaRESUMEN
Getah virus (GETV) is a mosquito-borne, single-stranded, positive-sense RNA virus belonging to the genus Alphavirus of the family Togaviridae. Natural infections of GETV have been identified in a variety of vertebrate species, with pathogenicity mainly in swine, horses, bovines, and foxes. The increasing spectrum of infection and the characteristic causing abortions in pregnant animals pose a serious threat to public health and the livestock economy. Therefore, there is an urgent need to establish a method that can be used for epidemiological investigation in multiple animals. In this study, a real-time reverse transcription fluorescent quantitative PCR (RT-qPCR) method combined with plaque assay was established for GETV with specific primers designed for the highly conserved region of GETV Nsp1 gene. The results showed that after optimizing the condition of RT-qPCR reaction, the minimum detection limit of the assay established in this study was 7.73 PFU/mL, and there was a good linear relationship between viral load and Cq value with a correlation coefficient (R 2) of 0.998. Moreover, the method has good specificity, sensitivity, and repeatability. The established RT-qPCR is 100-fold more sensitive than the conventional RT-PCR. The best cutoff value for the method was determined to be 37.59 by receiver operating characteristic (ROC) curve analysis. The area under the curve (AUC) was 0.956. Meanwhile, we collected 2,847 serum specimens from swine, horses, bovines, sheep, and 17,080 mosquito specimens in Shandong Province in 2022. The positive detection rates by RT-qPCR were 1%, 1%, 0.2%, 0%, and 3%, respectively. In conclusion, the method was used for epidemiological investigation, which has extensive application prospects.
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Porcine reproductive and respiratory syndrome virus (PRRSV) and Porcine circovirus (PCV) are two important pathogens, which caused respiratory disease in pigs. PRRSV and PCV2 had caused great economic losses to the pig industry. Pigs coinfection with PCV2 and PRRSV were common in the clinic, PCV2 antibodies can be detected in most of the pigs. PCV2d and HP-PRRSV(JXA1-like) were two major viruses circulating in the pigs in China. In this study, HP-PRRSV (JXA1-like) and PCV2d were used to coinfect and (or) sequential infect 5-week-old weaned PCV2-antibody positive pigs and the clinical indications, pathological, virus load, and specific antibodies of the challenged post-weaned piglets were evaluated. Thirty 5-week-old post-weaned pigs were divided into six groups infected with PBS, PCV2, PRRSV, PCV2-PRRSV, PRRSV-PCV2, and Co-PRRSV-PCV2 according to the PCV2 specific antibodies. Pigs infected with PRRSV can experience diarrhea, increased body temperature, weight loss, and even death. The pigs in the PRRSV infected group and PRRSV-PCV2 infected group showed severe clinical symptoms, high mortality, and low average daily gain. The main pathological changes were widening of the lung interstitium, lung adhesion, and so on. The PRRSV-PCV2 infected group showed high levels of TNF-α and IL-2. In conclusion, PRRSV and PRRSV-PCV2 sequential infected pigs showed most pathogenic signs, and PCV2-PRRSV sequential infected pigs showed less pathogenicity than pigs of PCV2 and PRRSV coinfection and PRRSV monoinfection from day 10-14, partially suppressing the cytokine storm produced by PRRSV.
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Infecciones por Circoviridae , Coinfección , Síndrome Respiratorio y de la Reproducción Porcina , Virus del Síndrome Respiratorio y Reproductivo Porcino , Enfermedades de los Porcinos , Porcinos , Animales , Coinfección/veterinaria , Virulencia , Anticuerpos AntiviralesRESUMEN
Thousands of people die each year from Japanese encephalitis (JE) caused by the Japanese encephalitis virus (JEV), probably due to exacerbation of the inflammatory response that impairs the course of the disease. Microglia are mononuclear phagocytic cells located within the parenchyma of the central nervous system; these play a key role in the innate immune response against JEV infections. However, the involvement of toll-like receptor 2 (TLR2) in the inflammatory response during the early stages of JEV infection in BV2 cells remains. Here, we evaluated protein profiles and determined the role of TLR2 in the inflammatory response of JEV-infected BV2 cells. High-depth tandem mass tags labeling for quantitative proteomics was used to assess JEV infected-BV2 cells and compare immune response profiles at 6, 12, and 24 h post-infection (hpi). In total, 212 upregulated proteins were detected at 6 hpi, 754 at 12 h, and 191 at 24 h. According to GO and KEGG enrichment analysis, the upregulated proteins showed enrichment for proteins related to the immune response. Parallel reaction monitoring tests, western blotting, and qPCR results showed that the adaptor protein MyD88 was not activated. The expression levels of key proteins downstream of MyD88, such as IRAK1, IRAK4, and TRAF6 did not increase; however, the expression levels of PI3K-AKT did increase. By inhibiting key proteins (TLR2, PI3K, and AKT) we confirmed that JEV activated TLR2, thus resulting in a robust inflammatory response. Consequently, the TLR2-PI3K-AKT signaling axis was proven to play a critical in the early stages of the JEV infection-induced inflammatory response in microglia.
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The wide spread of coronavirus disease 2019 (COVID-19) has significantly threatened public health. Human herd immunity induced by vaccination is essential to fight the epidemic. Therefore, highly immunogenic and safe vaccines are necessary to control SARS-CoV-2, whose S protein is the antigenic determinant responsible for eliciting antibodies that prevent viral entry and fusion. In this study, we developed a SARS-CoV-2 DNA vaccine expressing the S protein, named pVAX-S-OP, which was optimized according to the human-origin codon preference and using polyinosinic-polycytidylic acid as an adjuvant. pVAX-S-OP induced specific antibodies and neutralizing antibodies in BALB/c and hACE2 transgenic mice. Furthermore, we observed 1.43-fold higher antibody titers in mice receiving pVAX-S-OP plus adjuvant than in those receiving pVAX-S-OP alone. Interferon gamma production in the pVAX-S-OP-immunized group was 1.58 times (CD3+CD4+IFN-gamma+) and 2.29 times (CD3+CD8+IFN-gamma+) lower than that in the pVAX-S-OP plus adjuvant group but higher than that in the control group. The pVAX-S-OP vaccine was also observed to stimulate a Th1-type immune response. When, hACE2 transgenic mice were challenged with SARS-CoV-2, qPCR detection of N and E genes showed that the viral RNA loads in pVAX-S-OP-immunized mice lung tissues were 104 times and 106 times lower than those of the PBS control group, which shows that the vaccine could reduce the amount of live virus in the lungs of hACE2 mice. In addition, pathological sections showed less lung damage in the pVAX-S-OP-immunized group. Taken together, our results demonstrated that pVAX-S-OP has significant immunogenicity, which provides support for developing SARS-CoV-2 DNA candidate vaccines.
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COVID-19 , Vacunas de ADN , Animales , Humanos , Ratones , Adyuvantes Inmunológicos , Anticuerpos Neutralizantes , Anticuerpos Antivirales , COVID-19/prevención & control , Inmunidad Celular , Ratones Transgénicos , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/genética , Vacunas de ADN/genéticaRESUMEN
Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) is the causative agent of Porcine Reproductive and Respiratory Syndrome (PRRS), which has caused huge economic losses to the pig industry worldwide. PRRSV NADC34-Like PRRSV 2020-Acheng-1 strain, which caused high morbidity and high mortality were isolated from dead piglets (high-throughput sequencing to show that only PRRSV and TGEV) on a farm in northeastern China. The full-length genome sequence of 2020-Acheng-1 shares 95.6% nucleotide homology with NADC34 PRRSV without any gene insertion, but has a unique 17 amino acid (469aa to 486aa) deletion in Nsp2 compared with all NADC34-Like strains in NCBI and there are unique 100 amino acid deletions. In addition, difference degree of changes in signal peptide, trans-membrane region (TM), main neutralizing epitope (PNE), non-neutralizing epitope and N-glycosylation site were observed in GP5 of 2020-Acheng-1 and other PRRSV-2 strains, we only found a change in the fifteenth amino acid of signal peptide of in GP5 of 2020-Acheng-1 with NADC34 strains. Recombination analysis showed that 2020-Acheng-1 strain did not have any recombination events with representative PRRSV-2 strains in China. This study provided valuable evidence for understanding the role of NADC34-Like strain that impact on pathogenicity.
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Síndrome Respiratorio y de la Reproducción Porcina , Virus del Síndrome Respiratorio y Reproductivo Porcino , Enfermedades de los Porcinos , Animales , Porcinos , Virus del Síndrome Respiratorio y Reproductivo Porcino/genética , Filogenia , Aminoácidos , Señales de Clasificación de Proteína/genética , Epítopos , China/epidemiología , Variación Genética , Genoma Viral/genéticaRESUMEN
Chikungunya virus (CHIKV) is a mosquito-borne virus. The emergence of CHIKV infection has raised global concern, and there is a growing need to develop safe and effective vaccines. Here, adenovirus 5 was used as the vaccine vector to construct recombinant adenoviruses expressing CHIKV E2, E1, and E2-6K-E1, respectively. And then the immunogenicity and protective efficiency against CHIKV were evaluated in BALB/c mice. Compared to the ad-wt control group, all three vaccines elicited significant humoral and cellar immune responses. The levels of neutralizing antibodies in the rAd-CHIKV-E2-6K-E1 and rAd-CHIKV-E2 groups both reached 1:256, which were 3.2 times higher than those in the rAd-CHIKV-E1 group. Furthermore, the levels of lymphocyte proliferation in rAd-CHIKV-E2-6K-E1 group were the highest. Besides, the concentrations of IFN-γ and IL-4 in mice immunized with rAd-CHIKV-E2-6K-E1 were 1.37 and 1.20 times higher than those in ad-wt immunized mice, respectively. After the challenge, mice in the rAd-CHIKV-E2-6K-E1 and rAd-CHIKV-E2 groups lost 2% of their body weight compared with 5% in the ad-wt control group. And low viral loads were detected in the heart, kidney, and blood of mice immunized with rAd-CHIKV-E2-6K-E1 and rAd-CHIKV-E2 at 3-5 dpc, which decreased by 0.4-0.7 orders of magnitude compared with the ad-wt control. Overall, these data suggest that the recombinant adenovirus is a potential candidate vaccine against CHIKV.
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Infecciones por Adenoviridae , Vacunas contra el Adenovirus , Fiebre Chikungunya , Virus Chikungunya , Vacunas Virales , Adenoviridae/genética , Animales , Anticuerpos Antivirales , Fiebre Chikungunya/prevención & control , Virus Chikungunya/genética , Ratones , Mosquitos Vectores , Vacunas Sintéticas/genética , Proteínas del Envoltorio Viral , Vacunas Virales/genéticaRESUMEN
Porcine parvovirus (PPV) is the main pathogen of reproductive disorders. In recent years, a new type of porcine parvovirus has been discovered and named porcine parvovirus 2 to 7 (PPV2-PPV7), and it is associated with porcine circovirus type 2 in pigs. Codon usage patterns and their effects on the evolution and host adaptation of different PPV sub-types are still largely unknown. Here, we define six main sub-types based on the Bayesian method of structural proteins of each sub-type of PPV, including PPV2, PPV3, PPV4, PPV5, PPV6, and PPV7, which show different degrees of codon usage preferences. The effective number of codons (ENC) indicates that all PPV sub-types have low codon bias. According to the codon adaptation index (CAI), PPV3 and PPV7 have the highest similarity with the host, which is related to the main popular tendency of the host in the field; according to the frequency of optimal codons (FOP), PPV7 has the highest frequency of optimal codons, indicating the most frequently used codons in its genes; and according to the relative codon deoptimization index (RCDI), PPV3 has a higher degree. Therefore, it is determined that mutational stress has a certain impact on the codon usage preference of PPV genes, and natural selection plays a very decisive and dominant role in the codon usage pattern. Our research provides a new perspective on the evolution of porcine parvovirus (PPV) and may help provide a new method for future research on the origin, evolutionary model, and host adaptation of PPV.
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Uso de Codones , Variación Genética , Adaptación al Huésped , Infecciones por Parvoviridae/virología , Parvovirus Porcino/genética , Enfermedades de los Porcinos/virología , Animales , Teorema de Bayes , Evolución Molecular , Genotipo , Mutación , Filogenia , Selección Genética , PorcinosRESUMEN
Porcine reproductive and respiratory syndrome virus (PRRSV) and porcine circovirus (PCVs) are two major viruses that affect pigs. Coinfections between PRRSV and PCV2 are frequently reported in most outbreaks, with clinical presentations involving dyspnea, fever, reduced feed intake, weight loss, and death in fattening pigs. The NADC30-like PRRSV and PCV2d are the main circulating virus strains found in China. This study determines the impact of NADC30-like PRRSV and PCV2d mono-infection and coinfection on the immune system, organ pathology, and viral shedding in five-week-old post-weaned pigs. Pigs were randomly divided into six groups: PBS, PRRSV, PCV2, PRRSV-PCV2 coinfection (co), and PRRSV-PCV2 or PCV2-PRRSV sequential infections. Fever, dyspnea, decreased feed intake, weight loss, and pig deaths occurred in groups infected with PRRSV, Co-PRRSV-PCV2, and PRRSV-PCV2. The viral load was higher in Co-PRRSV-PCV2, PRRSV-PCV2, and PCV2-PRRSV than those mono-infected with PRRSV or PCV2. Additionally, cytokines (IFN-γ, TNF-α, IL-4, and IL-10) produced by pigs under Co-PRRSV-PCV2 and PRRSV-PCV2 groups were more intense than the other groups. Necropsy findings showed hemorrhage, emphysema, and pulmonary adhesions in the lungs of pigs infected with PRRSV. Smaller alveoli and widened lung interstitium were found in the Co-PRRSV-PCV2 and PRRSV-PCV2 groups. In conclusion, PRRSV and PCV2 coinfection and sequential infection significantly increased viral pathogenicity and cytokine responses, resulting in severe clinical signs, lung pathology, and death.
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Infecciones por Circoviridae/veterinaria , Circovirus/fisiología , Circovirus/patogenicidad , Coinfección/virología , Síndrome Respiratorio y de la Reproducción Porcina/virología , Virus del Síndrome Respiratorio y Reproductivo Porcino/fisiología , Virus del Síndrome Respiratorio y Reproductivo Porcino/patogenicidad , Animales , China , Infecciones por Circoviridae/genética , Infecciones por Circoviridae/inmunología , Infecciones por Circoviridae/virología , Circovirus/genética , Coinfección/genética , Coinfección/inmunología , Coinfección/mortalidad , Femenino , Interleucina-10/genética , Interleucina-10/inmunología , Interleucina-4/genética , Interleucina-4/inmunología , Pulmón/inmunología , Pulmón/virología , Masculino , Síndrome Respiratorio y de la Reproducción Porcina/genética , Síndrome Respiratorio y de la Reproducción Porcina/inmunología , Síndrome Respiratorio y de la Reproducción Porcina/mortalidad , Virus del Síndrome Respiratorio y Reproductivo Porcino/genética , Porcinos , VirulenciaRESUMEN
BACKGROUND: Porcine vesicular disease is caused by the Seneca Valley virus (SVV), it is a novel Picornaviridae, which is prevalent in several countries. However, the pathogenicity of SVV on 5-6 week old pigs and the transmission routes of SVV remain unknown. METHODS: This research mainly focuses on the pathogenicity of the CH-GX-01-2019 strain and the possible vector of SVV. In this study, 5-6 week old pigs infected with SVV (CH-GX-01-2019) and its clinical symptoms (including rectal temperatures and other clinical symptoms) were monitored, qRT-PCR were used to detect the viremia and virus distribution. Neutralization antibody assay was set up during this research. Mosquitoes and Culicoides were collected from pigsties after pigs challenge with SVV, and SVV detection within mosquitoes and Culicoides was done via RT-PCR. RESULTS: The challenged pigs presented with low fevers and mild lethargy on 5-8 days post infection. The viremia lasted more than 14 days. SVV was detected in almost all tissues on the 14th day following the challenge, and it was significantly higher in the hoofs (vesicles) and lymph nodes in comparison with other tissues. Neutralizing antibodies were also detected and could persist for more than 28 days, in addition neutralizing antibody titers ranged from 1:128 to 1:512. Mosquitoes and Culicoides were collected from the pigsty environments following SVV infection. Although SVV was not detected in the mosquitoes, it was present in the Culicoides, however SVV could not be isolated from the positive Culicoides. CONCLUSIONS: Our work has enriched the knowledge relating to SVV pathogenicity and possible transmission routes, which may lay the foundation for further research into the prevention and control of this virus.
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Ceratopogonidae , Infecciones por Picornaviridae , Picornaviridae , Enfermedades de los Porcinos , Animales , Granjas , Mosquitos Vectores , Infecciones por Picornaviridae/veterinaria , Porcinos , VirulenciaRESUMEN
The V protein of Newcastle disease virus (NDV) has been shown to inhibit the secretion of interferon (IFN) during infection, which is responsible for the promotion of NDV pathogenicity. However, the ability of the V protein to suppress host innate immunity is not well understood. In this study, we explored the function of V protein and its relationship with virulence by generating V protein-inserted recombinant (r) NDVs. Using rNDVs as a model, we examined the efficiency of infection, IFN responses, and apoptosis of host cells during infection. We found that viral propagation occurred smoothly when V protein from lentogenic NDV is inserted instead of the V protein from the velogenic strain. The infection of lentogenic V protein-inserted rNDV induced less expression of IFNs and downstream antiviral proteins via efficient degradation of p-STAT1 and MDA5. Moreover, velogenic V protein triggered a higher apoptosis rate during infection thereby restricting the replication of NDV. Conversely, lentogenic V protein inhibits IFN responses efficiently and induces less apoptosis compared to the velogenic strain. Our findings provide a novel understanding of the role of V protein in NDV pathogenicity.
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Enfermedad de Newcastle/inmunología , Enfermedad de Newcastle/virología , Virus de la Enfermedad de Newcastle/genética , Virus de la Enfermedad de Newcastle/patogenicidad , Enfermedades de las Aves de Corral/inmunología , Enfermedades de las Aves de Corral/virología , Proteínas Virales , Animales , Apoptosis , Regulación de la Expresión Génica/inmunología , Interacciones Microbiota-Huesped/inmunología , Interferones/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Virales/genética , Proteínas Virales/metabolismoRESUMEN
A novel circovirus designated "porcine circovirus type 4" (PCV4) was recently reported in pigs with severe clinical disease in Hunan Province, China. Relatively little is known about the molecular epidemiology of this recently discovered virus. In order to assess the prevalence of PCV4 infection in pigs and to analyze its genomic characteristics, 1683 clinical samples were collected in Inner Mongolia, China, from 2016 to 2018. The overall infection rate of PCV4 was 1.6% (27/1683) at the sample level and 21.6% (11/51) at the farm level, with rates ranging from 3.2% (1/31) to 20.0% (6/30) on different PCV4-positive pig farms. In addition, the PCV4 infection rates at both the sample and farm level increased from 2016 to 2018. This also showed that PCV4 was present in pigs in 2016 in China and therefore did not arrive later than this date. Additionally, our findings showed that PCV4 infections had no association with PCV2 or PCV3 infections. We sequenced the complete genomes of three PCV4 strains and found that the PCV4 strains had a high degree of genetic stability but shared less than 80% sequence identity with other circoviruses. We identified six amino acid mutations in the Rep protein and seven in the Cap protein. Phylogenetic analysis based on Cap and Rep sequences confirmed that the PCV4 strains grouped in an independent branch. Our findings provide important information about the prevalence and genetic characteristics of PCV4 strains.
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Infecciones por Circoviridae/epidemiología , Circovirus/genética , Enfermedades de los Porcinos/epidemiología , Animales , China/epidemiología , Infecciones por Circoviridae/virología , Granjas , Genoma Viral/genética , Genómica/métodos , Epidemiología Molecular/métodos , Filogenia , Prevalencia , Estudios Retrospectivos , Porcinos , Enfermedades de los Porcinos/virologíaRESUMEN
The Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) cause a huge economic loss around the pig industry worldwide; the NADC30-like PRRSV have attracted much attention outbreaks in China in recent years. Recombination between PRRSV subtypes, point mutations, insertions and deletions that contribute to the emergence of new variants in the genome. In this study, the PRRSV-HB-16-China-2019 strain's full-length genomic sequence shares 93.0% nucleotide similarity to NADC30 PRRSV without any gene insertion. Compared with VR-2332, it has an NSP2 coding region that is different from NADC30, which has a discontinuous 206-aa (111-aa from position 323 to 433 and 95-aa from position 476 to 570) deletion. Compared with other NADC30-Like strains, it has a discontinuous 75-amino acid (75-aa from position 476 to 552) deletion, which was first reported. Notably, the strain, PRRSV-HB-16-China-2019, contained an addition a 1-aa deletion in ORF5 and a unique 3-nt deletion in 3'-UTR similar to NADC30, the strain is recombined between a NADC30-like strain and a vaccine strain named RespPRRS MLV(parental strain VR-2332). Our findings indicate that PRRSV-HB-16-China-2019 is a new NSP2-deletion NADC30-like strain with certain deletions and mutations. Our results show that the emergence of the new NADC30-like strain has increased the difficulty of PRRSV prevention in China.
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Síndrome Respiratorio y de la Reproducción Porcina , Virus del Síndrome Respiratorio y Reproductivo Porcino , Animales , China , Variación Genética , Genoma Viral , Filogenia , Virus del Síndrome Respiratorio y Reproductivo Porcino/genética , Recombinación Genética , PorcinosRESUMEN
Seneca Valley virus (SVV) is a novel Picornaviridae that is closely associated with porcine idiopathic vesicular disease (PIVD). Here, a novel SVV strain (CH-GX-01-2019) was detected and isolated from swine in Guangxi Province, China. The complete genomic sequence of CH-GX-01-2019 exhibited 93.3-98.9 % identify with other SVV isolates at the nucleotide level. CH-GX-01-2019 showed the highest level of similarity (98.9 %) with Vietnamese strains. And CH-GX-01-2019 exhibited two consecutive amino acid mutations in VP1 gene. Phylogenetic analysis based on the complete genome and the VP1 gene showed that Chinese SVV isolates can be divided into three clusters. We analyzed the geographical distributions of SVV strains in China and found that the epidemiology of SVV in China is complicated; most strains are distributed predominantly in south and central China. Between 2015 and 2019, the dominant epidemic SVV isolates in China have changed from clusters 1 and 3 to cluster 2. CH-GX-01-2019 (cluster 3) is a recombinant strain from Colombia-2016 (cluster 2) and HB-CH-2016 (cluster 1). Our findings will enhance our understanding of the prevalence and genetic variation of SVV in the swine herds of China and provide important insights into the molecular epidemiology of SVV.
Asunto(s)
Evolución Molecular , Filogenia , Infecciones por Picornaviridae/epidemiología , Infecciones por Picornaviridae/veterinaria , Picornaviridae/genética , Enfermedades de los Porcinos/epidemiología , Animales , Línea Celular , China/epidemiología , Cricetinae , Granjas , Genoma Viral , Ganado/virología , Picornaviridae/clasificación , Picornaviridae/aislamiento & purificación , Infecciones por Picornaviridae/virología , Prevalencia , Recombinación Genética , Porcinos , Enfermedades de los Porcinos/virología , Secuenciación Completa del GenomaRESUMEN
Porcine circovirus type 3 (PCV3) infection causes substantial economic losses in pig populations since its discovery in 2016. However, PCV3 molecular epidemiology remains need further study. In order to assess the prevalence of PCV3 infection in China, 4094 clinical samples from 271 pig farms in 10 provinces of China were evaluated by PCR. It was shown that the overall prevalence of PCV3 infection was 29.3 % (1200/4094) and 74.2 % (201/271) at sample and farm levels respectively, suggesting that PCV3 infection is prevalent in China. Furthermore, a statistical analysis showed PCV3 might exacerbate PCV2 and PRRSV infection rate and have a potential association with pig clinical disease. In addition, we sequenced the entire genome of 57 PCV3 strains; homology analysis showed that PCV3 strains have more than 96 % similarities at the nucleotide level, and PCV3 shares less than 60 % similarities with other circoviruses. By comparing the total 673 PCV3 strains from the NCBI GenBank, we found the major of amino acid mutations are located in predicted epitope regions and the mutations ratio changed during PCV3 evolution. Phylogenetic analysis revealed that all isolates belonged to PCV3a and PCV3b, and increasing PCV3a and decreasing PCV3b trends were observed during PCV3 evolution. Overall, this study provides important insights for understanding PCV3 prevalence, pathogenesis, and evolution and will guide future efforts to develop effective preventive and control measures.
Asunto(s)
Infecciones por Circoviridae/epidemiología , Infecciones por Circoviridae/veterinaria , Circovirus/genética , Circovirus/patogenicidad , Evolución Molecular , Enfermedades de los Porcinos/epidemiología , Animales , China/epidemiología , Circovirus/clasificación , Granjas , Genoma Viral , Ganado/virología , Mutación , Filogenia , Prevalencia , Porcinos , Enfermedades de los Porcinos/virología , Proteínas Virales/genética , Secuenciación Completa del GenomaRESUMEN
Porcine reproductive and respiratory syndrome virus (PRRSV) is an RNA virus that causes reproductive failure in sows and respiratory problems in piglets. PRRSV infection leads to substantial pig mortality and causing huge economic losses so that disease outbreaks caused by the new PRRSV strain from other regions have caused great concern in China. In this study, we analysed the pathogenicity of the novel ORF5 RFLP 1-7-4-like PRRSV strain, named PRRSV-ZDXYL-China-2018-1 in pigs. The viral challenge test showed that PRRSV-ZDXYL-China-2018-1 infection can cause persistent fever, moderate dyspnoea, serum viraemia and interstitial pneumonia in piglets. The levels of viral loads in serum and PRRSV-specific antigen were also detected in lung tissues were used one-step Taq-Man RT-qPCR and Immunohistochemistry, respectively. At 28dpi, the level of specific antibodies was increased among infected piglets. Importantly, the new virus appeared be a moderately virulent isolate with pathogenicity compared to HP-PRRSV strain LQ (JXA1-like strain). Histological examination revealed severe monocyte haemorrhage and interstitial pneumonia associated with monocyte infiltration in the lung tissue of pigs infected with PRRSV-ZDXYL-China-2018-1 and LQ-JXA1 strains. Immunohistochemistry (IHC) results showed positive brown-red epithelial cells and macrophages in pig lungs. Therefore, it is critical to establish an effective strategy to control the spread of PRRSV in China.