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1.
BMC Vet Res ; 15(1): 342, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31619295

RESUMO

BACKGROUND: The objective of this study was to assess the efficacy of a trivalent vaccine mixture and compare it to the respective monovalent vaccines against Mycoplasma hyopneumoniae, porcine circovirus type 2 (PCV2), and porcine reproductive and respiratory syndrome virus (PRRSV). RESULTS: Pigs that were triple challenged with M. hyopneumoniae, PCV2, and PRRSV following vaccination with the trivalent vaccine mixture exhibited a significantly better growth performance when compared to unvaccinated and challenged pigs. A statistical difference was not found when comparing pig populations which were vaccinated with the trivalent vaccine followed by a triple challenge and pigs vaccinated with monovalent M hyopneumoniae vaccine followed by mycoplasmal single challenge in the following areas: M. hyopneumoniae nasal shedding, the number of M. hyopneumoniae-specific interferon-γ secreting cells (IFN-γ-SC), and mycoplasmal lung lesion scores. Pigs vaccinated with the trivalent vaccine mixture followed by a triple challenge resulted in a similar reduction of PCV2 viremia, an increase in the number of PCV2-specific IFN-γ-SC and reduction in interstitial lung lesion scores when compared to pigs vaccinated with a PCV-2 vaccine and challenged with PCV2 only. Lastly, there was a significant difference in the reduction of PRRSV viremia, an increase in PRRSV-specific IFN-γ-SC and a reduction of interstitial lung lesion scores between pigs vaccinated with the trivalent vaccine mixture followed by a triple challenge and pigs vaccinated with a monovalent PRRSV vaccine followed by PRRSV challenge only. CONCLUSION: The trivalent vaccine mixture was efficacious against a triple challenge of M. hyopneumoniae, PCV2, and PRRSV. The trivalent vaccine mixture, however, did not result in equal protection when compared against each respective monovalent vaccine, with the largest vaccine occurring within PRRSV.


Assuntos
Circovirus/imunologia , Mycoplasma hyopneumoniae/imunologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , Doenças dos Suínos/prevenção & controle , Vacinação/veterinária , Animais , Vacinas Bacterianas/imunologia , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/prevenção & controle , Feminino , Masculino , Pneumonia Suína Micoplasmática/imunologia , Pneumonia Suína Micoplasmática/prevenção & controle , Síndrome Respiratória e Reprodutiva Suína/imunologia , Síndrome Respiratória e Reprodutiva Suína/prevenção & controle , Sus scrofa , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/microbiologia , Doenças dos Suínos/virologia , Vacinas Combinadas/administração & dosagem , Vacinas Combinadas/imunologia , Vacinas Virais/imunologia
2.
Vet Microbiol ; 235: 86-92, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31282383

RESUMO

Although PCV2 infections generally cause mild disease in pigs, concurrent co-infections with other pathogens can damage the immune system and cause more severe diseases, collectively termed porcine circovirus associated diseases (PCVAD). Involvement of porcine parvovirus (PPV, a common cause of reproductive failure in naïve dams) in PCVAD caused by PCV2, has been reported. As this co-infection can be difficult to eliminate, there is a critical need to develop an effective vaccine to protect against PPV or synergistic effects of PCV2 and PPV under field conditions. In this study, we designed chimeric PCV2 virus-like particles (cVLPs) displaying a B-cell epitope derived from PPV1 structural protein around the surface of the 2-fold axes of PCV2 VLPs, based on 3D-structure analysis of the PCV2 capsid. The cVLPs were successfully prepared, verified by transmission electron microscopy and chromatography, with robust antibody titers against PCV2 and PPV1 produced in mice and guinea pigs. In addition, in guinea pigs challenged with 106 TCID50 PCV2, cVLPs conferred more effective immune protection (based on viral load) than a commercial PCV2 vaccine. Finally, antibody responses and immune protection against PPV were also evaluated. In guinea pigs vaccinated with cVLPs, although PPV antibodies detected by a hemagglutination inhibition (HI) assay appeared later after vaccination in the PCV2 cVLPs group than in the commercial PPV vaccine group, there were fewer PPV genomic DNA copies in the PCV2 cVLPs group than in a PBS group. In conclusion, guinea pigs vaccinated with cVLPs developed effective protective immunity against PCV2 challenge, with some protective immunity against PPV. This study provided valuable research data to pursue molecular design of chimeric epitopes PCV2 VLPs.


Assuntos
Infecções por Circoviridae/veterinária , Coinfecção/veterinária , Epitopos de Linfócito B/imunologia , Imunidade Humoral , Infecções por Parvoviridae/veterinária , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Linfócitos B/imunologia , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/prevenção & controle , Circovirus/imunologia , Coinfecção/virologia , Feminino , Cobaias , Camundongos , Infecções por Parvoviridae/imunologia , Infecções por Parvoviridae/prevenção & controle , Parvovirus Suíno/imunologia , Suínos , Doenças dos Suínos/prevenção & controle , Doenças dos Suínos/virologia , Vacinas Atenuadas/imunologia , Vacinas de Partículas Semelhantes a Vírus/imunologia
3.
Vet Microbiol ; 233: 93-101, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31176418

RESUMO

Actinobacillus pleuropneumoniae (APP) and porcine circovirus type 2 (PCV2) are both important pathogens of the porcine respiratory disease complex (PRDC), which results in significant worldwide economic losses. Recently, PCV2 and APP coinfection has been described in the worldwide pork industry, and represents an extremely complex situation in veterinary medicine. However, the mechanism of their coinfection has not been investigated. In this study, we found that PCV2 promoted APP adhesion to and invasion of porcine alveolar macrophages (PAMs) during coinfection. Additionally, PCV2 suppressed reactive oxygen species (ROS) production by inhibiting cytomembrane NADPH oxidase activity, which was beneficial for APP survival in PAMs in vitro. During coinfection, PCV2 weakened the inflammatory response and macrophage antigen presentation by decreasing TNF-α, IFN-γ and IL-4 expression, and reduced clearance of the invading bacteria. The host-cell experimental results were verified in a mouse model. The findings provide a deeper and novel understanding of porcine coinfection, and will be extremely helpful for the design of strategies for PRDC control.


Assuntos
Actinobacillus pleuropneumoniae/fisiologia , Circovirus/fisiologia , Coinfecção/veterinária , Macrófagos Alveolares/microbiologia , Macrófagos Alveolares/virologia , Espécies Reativas de Oxigênio/metabolismo , Infecções por Actinobacillus/imunologia , Infecções por Actinobacillus/veterinária , Animais , Anticorpos Antivirais/imunologia , Apresentação do Antígeno , Aderência Bacteriana , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/veterinária , Citocinas/genética , Citocinas/imunologia , Feminino , Inflamação , Masculino , Camundongos , Camundongos Endogâmicos ICR , Viabilidade Microbiana , NADPH Oxidases/metabolismo , Suínos
4.
PLoS One ; 14(6): e0219175, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31251772

RESUMO

Infections with immunosuppressive pigeon circovirus (PiCV) pose the most severe health problem to the global pigeon breeding. The vaccination with immunogenic PiCV recombinant capsid protein (PiCV rCP) is a potential tool for disease control. Because of the high prevalence of PiCV asymptomatic infections, the subclinically infected pigeons will be vaccinated in practice. The aim of this study was to answer a question if vaccination of asymptomatic, infected with PiCV pigeons induces a similar immune response to PiCV rCP as in uninfected birds. One hundred and twenty 6-week-old carrier pigeons were divided into 4 groups (2 groups of naturally infected and uninfected with PiCV individuals). Birds from groups V and V1 were vaccinated twice with PiCV rCP mixed with an adjuvant, whereas pigeons from groups C and C1 were immunized with an adjuvant only. The expression of genes encoding IFN-γ, CD4, and CD8 T lymphocyte receptors; the number of anti-PiCV rCP IgY-secreting B cells (SBC) and anti-PiCV rCP IgY were evaluated 2, 21, 39 and 46 days post vaccination (dpv). Study results showed that the expression of CD8 and IFN-γ genes was higher in both groups of infected pigeons than in the uninfected birds, irrespective of vaccination. In the uninfected birds, the expression of these genes was insignificantly higher in the vaccinated pigeons. The anti-PiCV rCP IgY-SBC were detected on 2 and 23 dpv and seroconversion was noted on 23 and 39 dpv in V and V1 groups, respectively. In the light of the results obtained, it could be concluded that pigeon circovirus recombinant capsid protein elicits the immune response in both naturally infected and uninfected pigeons, but its rate varies depending on PiCV infectious status. The infection with PiCV masks the potential cellular immune response to the vaccination with PiCV rCP and leads to the suppression of humoral immunity.


Assuntos
Doenças das Aves/tratamento farmacológico , Proteínas do Capsídeo/administração & dosagem , Infecções por Circoviridae/veterinária , Circovirus/metabolismo , Vacinas Virais/administração & dosagem , Animais , Anticorpos Antivirais/metabolismo , Doenças das Aves/imunologia , Antígenos CD8/genética , Proteínas do Capsídeo/imunologia , Infecções por Circoviridae/tratamento farmacológico , Infecções por Circoviridae/imunologia , Circovirus/imunologia , Columbidae , Interferon gama/genética , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/imunologia , Resultado do Tratamento , Regulação para Cima , Vacinação/veterinária , Vacinas Virais/imunologia
5.
Biomed Pharmacother ; 112: 108741, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30970528

RESUMO

Seaweeds are excellent source of bioactive compounds and seaweed-derived polysaccharides have demonstrated an array of biological effects. Here, we investigated the effect of polysaccharide of Sargassum weizhouense (PSW) on the inflammatory response in porcine circovirus type 2 (PCV2) infected mice and the underlying mechanism was studied according to the histone acetylation. After PCV2 infection, the levels of TNF-α, IL-1ß, IL-6, IL-8, IL-10, MCP-1, COX-1, COX-2 and HAT in both serum and spleen were significantly increased (P <0.05). The mRNA expression of TNF-α, IL-6, IL-10 and NF-κB p65 were elevated in PCV2 infected mice (P <0.05). The HDAC content in both serum and spleen as well the mRNA expression of HDAC1 were greatly decreased (P <0.05). PSW treatment dramatically inhibited the secretions of inflammatory cytokines and HATs, reduced mRNA expression of TNF-α, IL-6, IL-10 and NF-κB p65, but promoted HDAC secretion and mRNA expression of HDAC1 in PCV2-infected mice. The acetylation of both H3 and H4 was significantly up-regulated in PCV2-infected mice, and strongly inhibited by PSW treatment (P <0.01). These results suggested that PCV2 mediate the equilibrium between HATs and HDACs, alternate the histone acetylation and thus DNA packaging, and then activate the transcription of inflammatory cytokines. PSW could inhibit the histone acetylation and the production of inflammatory cytokines, showing excellent potentials in improving the resistance of host against PCV2 infection.


Assuntos
Antivirais/uso terapêutico , Infecções por Circoviridae/tratamento farmacológico , Histonas/metabolismo , Polissacarídeos/uso terapêutico , Sargassum/química , Acetilação , Animais , Antivirais/isolamento & purificação , Infecções por Circoviridae/imunologia , Citocinas/sangue , Feminino , Histona Acetiltransferases/metabolismo , Histona Desacetilases/metabolismo , Inflamação , Masculino , Camundongos Endogâmicos , Polissacarídeos/isolamento & purificação , Baço/imunologia
6.
Vet Microbiol ; 231: 87-92, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30955830

RESUMO

The objective of this study was to compare the efficacy of a commercial porcine circovirus type 2a (PCV2a) subunit vaccine against experimental PCV2a, PCV2b, and PCV2d challenge. A total of 105 pigs were randomly divided into 7 groups (15 pigs per group). At 21 days old the pigs were intramuscularly administered the PCV2a vaccine as a 1.0 mL dose. Four weeks following vaccination, pigs were challenged with either Korean PCV2a, PCV2b, or PCV2d. All vaccinated pigs showed a significant (P < 0.05) reduction of clinical signs, PCV2 viremia, lymphoid lesions, and lymphoid PCV2 antigen levels compared to unvaccinated control pigs. Vaccination resulted also in significantly higher (P < 0.05) titers of neutralizing antibody against PCV2, and an increase in the frequency of PCV2-specific interferon-γ secreting cells (IFN-γ-SC). The vaccine showed similar protection among the vaccinated groups regardless of the genotype of the challenge. Interestingly, vaccinated pigs had higher levels of neutralizing antibody titers against PCV2a compared to PCV2b or PCV2d while the number of PCV2a-, PCV2b-, and PCV2d-specific IFN-γ-SC were similar. Taken together, the results presented here demonstrate that a PCV2a vaccine can be effective against experimental PCV2a, PCV2b, and PCV2d challenge.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Circoviridae/veterinária , Doenças dos Suínos/prevenção & controle , Vacinas Virais/uso terapêutico , Animais , Anticorpos Neutralizantes/sangue , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/prevenção & controle , Circovirus/genética , Circovirus/imunologia , DNA Viral/sangue , Fazendas , Genótipo , Injeções Intramusculares , Interferon gama/imunologia , Gado , Distribuição Aleatória , Suínos , Doenças dos Suínos/imunologia , Vacinação , Vacinas de Subunidades/imunologia , Vacinas de Subunidades/uso terapêutico , Vacinas Virais/imunologia
7.
Vet Res ; 50(1): 19, 2019 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-30836990

RESUMO

Porcine circovirus type 2 (PCV2) is an economically important swine pathogen but some extra trigger factors are required for the development of PCV2-associated diseases. By evaluating cap protein expression, viral DNA copies and the number of infected cells, the present study further confirmed that oxidative stress can promote PCV2 replication. The results showed that oxidative stress induced autophagy in PCV2-infected PK15 cells. Blocking autophagy with inhibitor 3-methyladenine or ATG5-specific siRNA significantly inhibited oxidative stress-promoted PCV2 replication. Importantly, autophagy inhibition significantly increased apoptosis in oxidative stress-treated PK15 cells. Suppression of apoptosis by benzyloxycarbonyl-Val-Ala-Asp fluoromethylketone in conditions of autophagy inhibition restored PCV2 replication. Taken together, autophagy protected host cells against potential apoptosis and then contributed to PCV2 replication promotion caused by oxidative stress. Our findings can partly explain the pathogenic mechanism of PCV2 related to the oxidative stress-induced autophagy.


Assuntos
Apoptose , Autofagia , Infecções por Circoviridae/veterinária , Circovirus/fisiologia , Estresse Oxidativo , Doenças dos Suínos/virologia , Replicação Viral , Animais , Western Blotting/veterinária , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/metabolismo , Infecções por Circoviridae/virologia , Citocinas/metabolismo , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Glutationa/metabolismo , Peróxido de Hidrogênio/metabolismo , RNA Interferente Pequeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/metabolismo , Transfecção
8.
Acta Virol ; 63(1): 19-25, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30879309

RESUMO

Chicken infectious anemia (CIA) is an immunosuppressive disease that causes great economic loss in poultry industry globally. This disease is caused by chicken anemia virus (CAV), an icosahedral and single-stranded DNA virus that is transmitted both vertically and horizontally. CAV, which belongs to the genus Gyrovirus has been reported in human, mouse and dog feces. Rapid identification of different strains of gyrovirus with high similarity to CAV has heightened public concern on this virus. Clinical symptoms of this disease such as intramuscular hemorrhage, weight loss, anemia and bone marrow aplasia are prominent in young chickens, while adult chickens experience subclinical symptoms. Biosecurity measures such as good management practice and vaccination have been the most reliable control strategy against this virus. Therefore, this study reviews the current state of CAV under the following subheadings (i) Chicken anemia virus (ii) Pathogenesis of CAV (iii) Serological evaluation of host antibodies to CAV (iv) Association of Marek's disease and infectious bursa disease with CAV infection (v) Genetic diversity and phylogenetics of CAV strains (vi) Current and future vaccine strategy in the control of CAV. In conclusion, improvement on DNA and recombinant vaccines strategy could curtail the economic impact of CAV on poultry birds. Keywords: adjuvant; CAV; chicken; disease.


Assuntos
Vírus da Anemia da Galinha , Infecções por Circoviridae , Doenças das Aves Domésticas , Animais , Anticorpos Antivirais/sangue , Vírus da Anemia da Galinha/classificação , Vírus da Anemia da Galinha/imunologia , Galinhas , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/veterinária , Infecções por Circoviridae/virologia , Aves Domésticas , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/virologia , Vacinação/tendências , Vacinação/veterinária , Vacinas Virais/normas
9.
Vet Microbiol ; 230: 123-129, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30827377

RESUMO

Immunosuppressive viral diseases have a great economic importance in the poultry industry due to the increased susceptibility to secondary infections. Chicken anaemia virus (CAV) is one of the major immunosuppressive diseases in chickens. In addition, low pathogenic avian influenza (LPAI) of subtype H9N2 and infectious bronchitis (IB) viruses are among the most frequently reported respiratory viral diseases in poultry worldwide. In the present study, specific pathogen free chickens were used to understand the impact of CAV on secondary infection with LPAI-H9N2 or IB viruses. Clinical outcomes, viral shedding dynamics, and cytokine levels wereassessed. The results exhibit that chickens previously infected with CAV produceconsiderablyhigher titresof LPAI-H9N2 or IB viruses in the oropharyngeal swabs (P < 0.05), tracheas and kidneys. In addition, the immunologic effect of CAV provokedthe development of clinical signs of LPAI-H9N2 and IB virus infections. Moreover, results suggested that pre-infection with CAV directly correlated with elevated levels of IL-6 and IFNγ. These findings underline the importance of CAV pre-infection on LPAI-H9N2 or IB infection in chickens, and indicate that co-circulation of CAV can contribute to the spread and evolution of LPAI H9N2 and IB viruses.


Assuntos
Infecções por Circoviridae/veterinária , Coinfecção/veterinária , Infecções por Coronavirus/veterinária , Influenza Aviária/imunologia , Doenças das Aves Domésticas/virologia , Animais , Vírus da Anemia da Galinha/imunologia , Galinhas/virologia , Infecções por Circoviridae/imunologia , Coinfecção/imunologia , Coinfecção/virologia , Infecções por Coronavirus/imunologia , Citocinas/sangue , Vírus da Bronquite Infecciosa/imunologia , Vírus da Influenza A Subtipo H9N2 , Doenças das Aves Domésticas/imunologia , Organismos Livres de Patógenos Específicos , Eliminação de Partículas Virais
10.
Vet Res ; 50(1): 17, 2019 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-30819249

RESUMO

Porcine circovirus-associated disease (PCVAD) is one of the most serious infectious diseases in pigs worldwide. The primary causative agent of PCVAD is porcine circovirus type 2 (PCV2), which can cause lymphoid depletion and immunosuppression in pigs. Our previous study demonstrated that Laiwu (LW) pigs, a Chinese indigenous pig breed, have stronger resistance to PCV2 infection than Yorkshire × Landrace (YL) pigs. In this study, we found that the YL pigs showed more severe lymphocyte apoptosis and higher viral load in the spleen tissue than LW pigs. To illustrate the differential gene expression between healthy and infected spleens, transcriptome profiling of spleen tissues from PCV2-infected and control YL pigs was compared by RNA sequencing. A total of 90 differentially expressed genes (DEGs) was identified, including CD207, RSAD2, OAS1, OAS2, MX2, ADRB3, CXCL13, CCR1, and ADRA2C, which were significantly enriched in gene ontology (GO) terms related to the defense response to virus and cell-cell signaling, and another nine DEGs, KLF11, HGF, PTGES3, MAP3K11, XDH, CYCS, ACTC1, HSPH1, and RYR2, which were enriched in GO terms related to regulation of cell proliferation or apoptosis. Among these DEGs, the CXCL13 gene, which can suppress lymphocyte apoptosis during PCV2 infection, was significantly down-regulated in response to PCV2 infection in YL but not in LW pigs. By analysis of the regulatory elements in the promoter and 3'-untranslated region (3'-UTR) of porcine CXCL13, we found that the single nucleotide polymorphism (SNP) -1014 G (LW) > A (YL) and the Sus scrofa microRNA-296-5p (ssc-miR-296-5p) participated in regulating CXCL13 expression during the response to PCV2 infection.


Assuntos
Apoptose , Quimiocina CXCL13/metabolismo , Infecções por Circoviridae/veterinária , Circovirus , Linfócitos/virologia , Baço/virologia , Doenças dos Suínos/virologia , Animais , Western Blotting/veterinária , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/metabolismo , Infecções por Circoviridae/virologia , Circovirus/metabolismo , DNA Viral/genética , Citometria de Fluxo/veterinária , Perfilação da Expressão Gênica/veterinária , Regulação Viral da Expressão Gênica , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Análise de Sequência de RNA/veterinária , Baço/metabolismo , Baço/patologia , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/metabolismo , Carga Viral/veterinária
11.
J Microbiol Biotechnol ; 29(3): 482-488, 2019 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-30609882

RESUMO

Porcine circovirus type 2 (PCV2) is the causative agent of postweaning multisystemic wasting syndrome (PMWS) in pigs. Replicase (Rep) proteins are considered essential for viral replication. Capsid (Cap) protein is the primary immunogenic protein that induces protective immunity. Little is known about comparison on the immunogenicity of PCV2 Rep and Cap fusion protein and Cap protein. In the present study, recombinant baculoviruses expressing the Rep-Cap fusion protein (Bac-Rep-Cap) and the Cap protein (Bac-Cap) of PCV2 were constructed and confirmed with western blot and indirect fluorescence assay. Immunogenicities of the two recombinant proteins were tested in mice. The titers of antibodies were determined with a PCV2-specific enzyme-linked immunosorbent assay (ELISA) and a serum neutralization assay. The IFN-γ response of immunized mice was measured by ELISA. The mice immunized with the Bac-Rep-Cap and Bac-Cap successfully produced Cap-specific immunoreaction. The mice immunized with the Bac-Cap developed higher PCV2-specific neutralizing antibody titers than mice injected with the Bac-Rep-Cap. IFN-γ in the Bac-Rep-Cap group was increased compared to those in the Bac-Cap group. Vaccination of mice with the Bac-Rep-Cap showed significantly decreased protective efficacy compared to the Bac-Cap. Our findings will indubitably not only lead to a better understanding of the immunogenicity of PCV2, but also improved vaccines.


Assuntos
Proteínas do Capsídeo/imunologia , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/prevenção & controle , Imunogenicidade da Vacina/imunologia , Proteínas Recombinantes de Fusão/imunologia , Vacinas de Partículas Semelhantes a Vírus/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais/sangue , Formação de Anticorpos , Baculoviridae/genética , Western Blotting , Proteínas do Capsídeo/biossíntese , Proteínas do Capsídeo/genética , Circovirus/patogenicidade , Citocinas/sangue , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Vetores Genéticos , Injeções Intramusculares , Interferon gama/sangue , Camundongos , Camundongos Endogâmicos BALB C , Testes de Neutralização , Proteínas Recombinantes de Fusão/genética , Vacinação , Vacinas de Partículas Semelhantes a Vírus/biossíntese , Vacinas de Partículas Semelhantes a Vírus/genética , Vacinas Virais/genética , Vacinas Virais/farmacologia
12.
Poult Sci ; 98(2): 621-628, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30358862

RESUMO

Inclusion body hepatitis-hydropericardium syndrome (IBH-HPS) caused by fowl adenovirus type 4 (FAdV-4) has caused huge economic losses for China in the past five years. At present, this disease is controlled in many flocks with the inactivated FAdV vaccine, but the offspring chicks of a layer breeding flock that were vaccinated with this vaccine still became infected and developed IBH-HPS with a 20% mortality rate. Analysis revealed that the NDV-attenuated vaccine in use from the above-mentioned poultry farm was simultaneously contaminated with FAdV-4 and chicken infectious anemia virus (CIAV). The FAdV and CIAV isolated from the vaccine were purified for the artificial preparation of an NDV-attenuated vaccine singly contaminated with FAdV or CIAV, or simultaneously contaminated with both of them. Seven-day-old layers with maternal FAdV antibody were inoculated with the artificially prepared, contaminated vaccines and assessed for corresponding indices. The experiments showed that no obvious symptoms occurred after using the NDV-attenuated vaccine singly contaminated with FAdV or CIAV; however, common IBH and occasional HPS-related death was found in birds after administering the NDV-attenuated vaccine co-contaminated with FAdV and CIAV. In conclusion, this study illustrated that CIAV could assist FAdV in breaking maternal FAdV antibody protection, which then caused the IBH-HPS after vaccination with the co-contaminated NDV vaccine.


Assuntos
Infecções por Adenoviridae/veterinária , Galinhas , Infecções por Circoviridae/veterinária , Hepatite Animal/imunologia , Doenças das Aves Domésticas/imunologia , Infecções por Adenoviridae/imunologia , Infecções por Adenoviridae/virologia , Animais , Aviadenovirus/imunologia , Vírus da Anemia da Galinha/imunologia , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/virologia , Feminino , Hepatite Animal/virologia , Corpos de Inclusão Viral/fisiologia , Vírus da Doença de Newcastle/imunologia , Doenças das Aves Domésticas/virologia , Distribuição Aleatória , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/imunologia
13.
Vet Microbiol ; 225: 40-47, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30322531

RESUMO

Duck circovirus (DuCV) is an immunosuppressive pathogen that causes a huge economic loss in the avian industry. Efficient vaccination has become a necessary strategy for preventing DuCV infection in the breeding industry. Three DNA vaccines encoding the Capsid (Cap) protein of DuCV were developed in this study, which were based on the eukaryotic vector pcDNA3.1 containing (i) the full length of Cap gene, pcDNA3.1-Cap, (ii) the Cap gene with a deletion of its nuclear localization signal (NLS) peptide encoding sequence, pcDNA3.1-CapΔNLS, and (iii) the Cap gene without NLS but harboring a fragment encoding the secretory signal peptide of tissue plasminogen activator (tPA), pcDNA3.1-tPA-CapΔNLS. Production of Cap protein-derived antigens from these three DNA vaccines was confirmed in vitro. The deletion of the NLS coding sequence of the Cap gene changed the subcellular location of the Capsid protein from the nucleus to the cytoplasm. Secretion of the Cap protein was observed in pcDNA3.1-tPA-CapΔNLS-transfected cells. The immunogenicity of these three DNA vaccines was assessed in vivo by measuring Cap-specific antibody and related cytokine levels. The results demonstrated that all these vaccines could induce a significant, specific immune response to protect ducks from DuCV challenge. Notably, higher titers of Cap-specific antibody were produced in ducks vaccinated with pcDNA3.1-tPA-CapΔNLS, which provided the highest protective efficacy at a rate of 90% in the challenge experiment. Taken together, DNA vaccines expressing the DuCV Cap protein show promising immunogenicity, which can be enhanced by replacing the NLS of the Cap protein with a secretory signal peptide of tPA.


Assuntos
Proteínas do Capsídeo/imunologia , Infecções por Circoviridae/veterinária , Circovirus/genética , Patos/imunologia , Doenças das Aves Domésticas/prevenção & controle , Vacinas de DNA/imunologia , Animais , Proteínas do Capsídeo/administração & dosagem , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/prevenção & controle , Infecções por Circoviridae/virologia , Circovirus/química , Ensaio de Imunoadsorção Enzimática , Vetores Genéticos/administração & dosagem , Vetores Genéticos/imunologia , Imunogenicidade da Vacina , Sinais de Localização Nuclear/deficiência , Sinais de Localização Nuclear/genética , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/virologia , Ativador de Plasminogênio Tecidual/genética , Ativador de Plasminogênio Tecidual/imunologia , Vacinas de DNA/administração & dosagem
14.
Viruses ; 10(10)2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30326643

RESUMO

Porcine circovirus type 2 (PCV2) is associated with various diseases which are designated as PCV2-associated diseases (PCVADs). Their severity varies among breeds. In the diseased pigs, virus is present in monocytes, without replication or full degradation. PCV2 entry and viral outcome in primary porcine monocytes and the role of monocytes in PCV2 genetic susceptibility have not been studied. Here, virus uptake and trafficking were analyzed and compared among purebreds Piétrain, Landrace and Large White and hybrid Piétrain × Topigs20. Viral capsids were rapidly internalized into monocytes, followed by a slow disintegration to a residual level. PCV2 uptake was decreased by chlorpromazine, cytochalasin D and dynasore. The internalized capsids followed the endosomal trafficking pathway, ending up in lysosomes. PCV2 genome was nicked by lysosomal DNase II in vitro, but persisted in monocytes in vivo. Monocytes from purebred Piétrain and the hybrid showed a higher level of PCV2 uptake and disintegration, compared to those from Landrace and Large White. In conclusion, PCV2 entry occurs via clathrin-mediated endocytosis. After entry, viral capsids are partially disintegrated, while viral genomes largely escape from the pathway to avoid degradation. The degree of PCV2 uptake and disintegration differ among pig breeds.


Assuntos
Infecções por Circoviridae/veterinária , Circovirus/fisiologia , Monócitos/virologia , Doenças dos Suínos/virologia , Animais , Cruzamento , Infecções por Circoviridae/genética , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/virologia , Circovirus/genética , Circovirus/isolamento & purificação , Genoma Viral , Monócitos/imunologia , Suínos , Doenças dos Suínos/genética , Doenças dos Suínos/imunologia , Internalização do Vírus
15.
Avian Dis ; 62(3): 272-285, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30339511

RESUMO

A healthy immune system is a cornerstone for poultry production. Any factor diminishing the immune responses will affect production parameters and increase cost. There are numerous factors, infectious and noninfectious, causing immunosuppression (IS) in chickens. This paper reviews the three viral diseases that most commonly induce IS or subclinical IS in chickens: Marek's disease virus (MDV), chicken infectious anemia virus (CIAV), and infectious bursal disease virus (IBDV), as well as the interactions among them. MDV-induced IS (MDV-IS) affects both humoral and cellular immune responses. It is very complex, poorly understood, and in many cases underdiagnosed. Vaccination protects against some but not all aspects of MDV-IS. CIAV induces apoptosis of the hemocytoblasts resulting in anemia, hemorrhages, and increased susceptibility to bacterial infections. It also causes apoptosis of thymocytes and dividing T lymphocytes, affecting T helper functions, which are essential for antibody production and cytotoxic T lymphocyte (CTL) functions. Control of CIAV is based on vaccination of breeders and maternal antibodies (MAbs). However, subclinical IS can occur after MAbs wane. IBDV infection affects the innate immune responses during virus replication and humoral immune responses as a consequence of the destruction of B-cell populations. Vaccines with various levels of attenuation are used to control IBDV. Interactions with MAbs and residual virulence of the vaccines need to be considered when designing vaccination plans. The interaction between IBDV, CIAV, and MDV is critical although underestimated in many cases. A proper control of IBDV is a must to have proper humoral immune responses needed to control CIAV. Equally, long-term control of MDV is not possible if chickens are coinfected with CIAV, as CIAV jeopardizes CTL functions critical for MDV control.


Assuntos
Vírus da Anemia da Galinha/imunologia , Galinhas , Herpesvirus Galináceo 2/imunologia , Imunossupressão/veterinária , Vírus da Doença Infecciosa da Bursa/imunologia , Doenças das Aves Domésticas/imunologia , Vacinas Virais/imunologia , Animais , Infecções por Birnaviridae/imunologia , Infecções por Birnaviridae/veterinária , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/veterinária , Imunidade Celular , Imunidade Humoral , Doença de Marek/imunologia , Vacinação/veterinária
16.
Benef Microbes ; 9(6): 951-961, 2018 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-30232907

RESUMO

In our previous study we confirmed an antiviral activity of probiotic Lactobacillus reuteri L26 which was mediated by stimulation of local intestinal immunity. The aim of this paper was to evaluate the influence of L. reuteri L26 on the systemic immune response in gnotobiotic mice infected with porcine circovirus type 2 (PCV2). A total of 30 germ-free mice were divided into 3 groups and animals in noninfected and infected control groups (NC and IC; n=10) received sterile de Man-Rogosa-Sharpe broth for 7 days and animals in experimental group L+PCV (n=10) were inoculated with L. reuteri L26. Subsequently, mice in L+PCV and IC groups were infected with PCV2; however, mice in the control group received virus cultivation medium (mock). The results showed an increase of percentage of cytotoxic cells (CD8+ and CD49b+CD8-) and oxidative burst of phagocytes, up-regulation of the gene expression of RANTES, granulocyte-macrophage colony-stimulating factor, interferon-γ and immunoglobulin A in blood above all in the later phase of infection (14 dpi) in L+PCV group accompanied by higher load of PCV2 in the serum. These findings indicate that L. reuteri L26 has a potential to induce systemic immune reaction, but in gnotobiotic mice immune stimulation can increase virus replication.


Assuntos
Infecções por Circoviridae/prevenção & controle , Circovirus/imunologia , Fatores Imunológicos/administração & dosagem , Lactobacillus reuteri/imunologia , Probióticos/administração & dosagem , Animais , Infecções por Circoviridae/imunologia , Citocinas/análise , Vida Livre de Germes , Imunoglobulina A/sangue , Lactobacillus reuteri/crescimento & desenvolvimento , Camundongos , Fagócitos/imunologia , Linfócitos T Citotóxicos/imunologia
17.
Vet Res ; 49(1): 80, 2018 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-30081944

RESUMO

Newcastle disease virus (NDV)-attenuated vaccine has been widely used since the 1950s and made great progress in preventing and controlling Newcastle disease. However, many reports mention exogenous virus contamination in attenuated vaccines, while co-contamination with fowl adenovirus (FAdV) and chicken infectious anaemia virus (CIAV) in the NDV-attenuated vaccine also emerged in China recently, which proved to be an important reason for the outbreaks of inclusion body hepatitis-hydropericardium syndrome in some flocks. It is amazing that exogenous virus contamination at extremely low doses still infected chickens and induced severe disease; thus, we speculated that there must be some interaction between the NDV-attenuated vaccine and the contaminated exogenous viruses within. Accordingly, simulation experiments were launched using FAdV and CIAV isolated from the abovementioned vaccine. The results showed that the pathogenicity of FAdV and CIAV co-infection through the contaminated vaccine was significantly higher than that of direct oral infection, while the synergistic reaction of these viruses and LaSota prompted their multiplication in vivo and disturbed the production of antibodies against each other. This study showed the interactions of FAdV, CIAV and LaSota after using contaminated NDV-attenuated vaccine, helping us to understand how the contaminated exogenous viruses cause infection and induce severe disease at a relatively low dose through the oral route.


Assuntos
Infecções por Adenoviridae/veterinária , Infecções por Circoviridae/veterinária , Doença de Newcastle/prevenção & controle , Vírus da Doença de Newcastle/imunologia , Doenças das Aves Domésticas/imunologia , Vacinas Virais/imunologia , Infecções por Adenoviridae/imunologia , Infecções por Adenoviridae/prevenção & controle , Animais , Aviadenovirus/imunologia , Aviadenovirus/patogenicidade , Vírus da Anemia da Galinha/imunologia , Vírus da Anemia da Galinha/patogenicidade , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/prevenção & controle , Doença de Newcastle/imunologia , Vírus da Doença de Newcastle/patogenicidade , Doenças das Aves Domésticas/prevenção & controle , Distribuição Aleatória , Organismos Livres de Patógenos Específicos , Vacinas Virais/administração & dosagem , Virulência
18.
Immunobiology ; 223(11): 663-670, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30005969

RESUMO

Porcine circovirus type 2 (PCV2)-associated diseases have led to great economic losses to the pig industry. Our lab previously found that conjugation of chitosan oligosaccharides (COS) or via a carrier protein enhanced the immunogenicity of PCV2 vaccine against infectious pathogens. However, precise mechanisms and signal transduction pathways underlying the efficacy of COS conjugation remains poorly defined. In this study, to better understand the effects and mechanism of COS conjugates maintain the adjuvant potential in vivo, we investigated its augmentation of macrophage function, including cell activation, NO production, cytokine production and phagocytosis. Additionally, the role of Toll-like receptors (TLR) proteins in this process was also assessed. The results indicate that, as compared to the PCV and PCV/COS, conjugation of COS effectively enhanced the NO production, cytokines generation and phagocytosis activity of macrophages. Noticeably, the generation of NO and proinflammatory cytokines was closely related to the TLR2/4 signaling pathways, strongly suggesting that conjugation of COS regulates innate and adaptive immunity by activation of macrophages, resulting in immune enhancement. In summary, the present study provides a potential mechanism of COS conjugation as a novel adjuvant to improve immune responses against various diseases.


Assuntos
Quitosana/imunologia , Infecções por Circoviridae/imunologia , Circovirus/fisiologia , Macrófagos/imunologia , Vacinas Virais/imunologia , Adjuvantes Imunológicos , Animais , Anticorpos Antivirais/sangue , Quitosana/química , Ativação de Macrófagos , Óxido Nítrico/metabolismo , Fagocitose , Transdução de Sinais , Suínos , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo
19.
Acta Trop ; 187: 214-221, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29949731

RESUMO

BACKGROUND: The productivity of pigs in smallholder systems is affected by high disease burden, most of which might not be obvious, with their epidemiology and impact being poorly understood. This study estimated the seroprevalence and identified the risk factors of a range of bacterial and viral pathogens of potential economic and public health importance in domestic pigs in Uganda. A total of 522 clinically healthy pigs were randomly selected from 276 pig farms in Masaka (142) and Lira (134) districts of Uganda in 2015. RESULTS: Overall the highest animal prevalence was found for Streptococcus suis 73.0% (CI95: 67.0-78.3) in Lira and 68.2% (CI95: 62.7-73.4) in Masaka; followed by Porcine circovirus type 2 with 50.8% (CI95: 44.5-57.2) in Lira and 40.7% (CI95: 35.2-46.5) in Masaka and Actinobacillus pleuro-pneumoniae, 25.6% (CI95: 20.4-31.6) in Lira and 20.5% (CI95: 16.2-25.6) in Masaka. Mycoplasma hyopneumonia prevalence was 20.9% (CI95: 16.2-26.6) in Lira and 10.1% (CI95: 7.1-14.1) in Masaka, while Porcine parvovirus was 6.2% (CI95: 4.0-9.7) in Masaka and 3.4% (CI95: 1.7-6.6) in Lira. Less common pathogens were Influenza A, 8.5% (CI95: 5.6-12.8) in Lira and 2.0% (CI95: 0.9-4.5) in Masaka and Porcine Reproductive and Respiratory Syndrome Virus, 1.7% (CI95: 0.7-4.3) in Lira and 1.3% (CI95: 0.5-3.5) in Masaka. Even less common was Rotavirus A with 0.8% (CI95: 0.2-3.0) in Lira and 0.7% (CI95: 0.2-2.5) in Masaka; the same was for Aujeszky virus with 0.4% (CI95: 0.7-2.4) in Lira and 0.0% (CI95: 0.0-0.1) in Masaka. Co-infection with two pathogens was common and there was a significant association of M. hyo and PCV2 co-occurrence (p = 0.016). Multivariate analysis showed that for S. suis the use of disinfectant reduced odds of sero-positivitey (OR = 0.15; p = 0.017) and pigs less than 6 months were more likely to be infected than older pigs (OR = 3.35; p = 0.047). For M. hyo, crossbred pigs had higher odd of infection compared to local breeds (OR = 1.59; p < 0.001). CONCLUSIONS: The studied pathogens have high prevalences in smallholder pig production systems and might be silent killers, thus affecting productivity and there is a possibility that some pathogens could spread to humans. Given the limited knowledge of veterinary workers and the poor diagnostic capacities and capabilities in these systems, the diseases are potentially usually under-diagnosed. These findings constitute baseline data to measure the impact of future interventions aiming to reduce disease burden in the pig production systems in Uganda.


Assuntos
Infecções por Circoviridae/veterinária , Fazendas , Infecções por Orthomyxoviridae/veterinária , Pneumonia Suína Micoplasmática/epidemiologia , Síndrome Respiratória e Reprodutiva Suína/epidemiologia , Infecções Estreptocócicas/veterinária , Sus scrofa , Doenças dos Suínos/epidemiologia , Animais , Animais Domésticos/microbiologia , Infecções por Circoviridae/epidemiologia , Infecções por Circoviridae/imunologia , Circovirus , Desinfetantes , Vírus da Influenza A , Análise Multivariada , Mycoplasma hyopneumoniae , Razão de Chances , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/imunologia , Pneumonia Suína Micoplasmática/imunologia , Síndrome Respiratória e Reprodutiva Suína/imunologia , Vírus da Síndrome Respiratória e Reprodutiva Suína , Prevalência , Fatores de Risco , Estudos Soroepidemiológicos , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/imunologia , Streptococcus suis , Suínos , Doenças dos Suínos/imunologia , Uganda/epidemiologia
20.
J Immunol ; 201(2): 533-547, 2018 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-29858268

RESUMO

Porcine circovirus (PCV) type 2 (PCV2), an immunosuppression pathogen, is often found to increase the risk of other pathogenic infections. Yet the relative immune mechanisms determining the susceptibility of PCV2-infected animals remain unclear. In this study, we confirmed that PCV2 infection suppressed IL-12p40 expression and host Th1 immune response, leading to a weakened pathogenic clearance upon porcine reproductive respiratory syndrome virus (PRRSV) or Haemophilus parasuis infection. PCV2 infection suppressed pathogens, LPS/IFN-γ, or LPS/R848-induced IL-12p40 expression in porcine alveolar macrophages. PCV2 capsid (Cap) was the major component to suppress IL-12p40 induction by LPS/IFN-γ, LPS/R848, PRRSV, or H. parasuis Either wild-type PCV2 or mutants PCV2-replicase 1 and PCV type 1-Cap2, which contained PCV2 Cap, significantly decreased IL-12p40 levels and increased the replication of PRRSV and H. parasuis in the lung tissues relative to mock or PCV type 1 infection. gC1qR, a Cap binding protein, was not involved in IL-12p40 induction but mediated the inhibitory effect of PCV2 Cap on IL-12p40 induction. PCV2 also activated PI3K/Akt1 and p38 MAPK signalings to inhibit IL-12p40 expression via inhibition of NF-κB p65 binding to il12B promoter and upregulation of miR-23a and miR-29b. Knockdown of Akt1 and p38 MAPK downregulated miR-23a and miR-29b and increased IL-12p40 expression. Inhibition of miR-23a and miR-29b attenuated the inhibitory effect of PCV2 on IL-12p40 induction, resulting in an increased IL-12p40 expression and Th1 cell population and reduced susceptibility to PRRSV or H. parasuis Taken together, these results demonstrate that PCV2 infection suppresses IL-12p40 expression to lower host Th1 immunity to increase the risk of other pathogenic infection via gC1qR-mediated PI3K/Akt1 and p38 MAPK signaling activation.


Assuntos
Infecções por Circoviridae/imunologia , Circovirus/fisiologia , Infecções por Haemophilus/imunologia , Haemophilus parasuis/imunologia , Macrófagos Alveolares/imunologia , MicroRNAs/genética , Síndrome Respiratória e Reprodutiva Suína/imunologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , Suínos/imunologia , Células Th1/imunologia , Animais , Proteínas do Capsídeo/genética , Proteínas do Capsídeo/metabolismo , Células Cultivadas , Imunossupressão , Subunidade p40 da Interleucina-12/genética , Subunidade p40 da Interleucina-12/metabolismo , Macrófagos Alveolares/virologia , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Mutação/genética , Fosfatidilinositol 3-Quinases/metabolismo , Receptores de Complemento/genética , Receptores de Complemento/metabolismo , Transdução de Sinais , Carga Viral , Replicação Viral
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