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1.
J Vet Diagn Invest ; 21(1): 88-96, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19139506

RESUMO

The IDEXX Swine influenza virus H1N1 and H3N2 enzyme-linked immunosorbent assays (ELISAs) are used worldwide, but their capacity to detect antibodies to European Swine influenza viruses (SIVs) has not been documented. A total of 313 well-defined sera from SIV seronegative pigs and pigs experimentally infected with European SIVs were used to compare the performance of both ELISAs and the hemagglutination inhibition (HI) test. The ELISAs largely failed to detect pigs that had been infected with H1N1 (0/42 positive in H1N1 ELISA) or H3N2 only (9/18 positive in H3N2 ELISA; group 1). Higher ELISA detection rates were found after consecutive infection of pigs with either H1N1 or H3N2 and 1 other subtype (7/40 and 11/22 positive in H1N1 and H3N2 ELISA, respectively; group 2). Of 39 pigs that had been vaccinated twice with 1 of 4 commercial SIV vaccines (group 3), 25 tested positive in the H1N1 and 4 in the H3N2 ELISA. Pigs that had received a single vaccination after a prior infection with H1N1 and/or H3N2 (group 4) were more frequently positive than group 1 or 3 pigs (23/24 and 15/24 positive in H1N1 and H3N2 ELISA, respectively). Both the H1N1 and H3N2 ELISA showed a low sensitivity (39% and 35%, respectively) relative to the HI test. Because pigs in the field are frequently infected and/or vaccinated with multiple SIV subtypes and variants, they are more likely to test positive in the ELISAs. However, the interpretation of ELISA results will be difficult, and HI remains the method of choice.


Assuntos
Anticorpos Antivirais/sangue , Ensaio de Imunoadsorção Enzimática/veterinária , Vírus da Influenza A Subtipo H1N1/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Infecções por Orthomyxoviridae/veterinária , Doenças dos Suínos/virologia , Animais , Ensaio de Imunoadsorção Enzimática/métodos , Europa (Continente) , Testes de Inibição da Hemaglutinação/veterinária , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/imunologia
2.
Microbes Infect ; 8(6): 1492-501, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16697680

RESUMO

Porcine respiratory coronavirus (PRCV) potentiates respiratory disease and proinflammatory cytokine production in the lungs upon intratracheal inoculation with lipopolysaccharide (LPS) at 1 day of infection. This study aimed to quantify LPS-binding protein (LBP), CD14 and haptoglobin in the lungs throughout a PRCV infection. LBP and CD14 recognize LPS and enhance its endotoxic activity, whereas haptoglobin dampens it. Gnotobiotic pigs were inoculated intratracheally with PRCV (n = 34) or saline (n = 5) and euthanized 1-15days post inoculation (DPI). Virus was detected in the lungs from 1 to 9DPI. Cell-associated CD14 in lung tissue increased up to 15 times throughout the infection, due to an increase in highly CD14+ monocyte-macrophages from 1 to 12DPI and CD14+ type 2 pneumocytes from 7 to 9DPI. LBP and soluble CD14 levels in bronchoalveolar lavage fluids were elevated from 1-12DPI, with up to 35- and 4-fold increases, respectively. Haptoglobin levels increased significantly (x4.5) at 7DPI. In addition, we found that PRCV could sensitize the lungs to LPS throughout the infection, but the response to LPS appeared less enhanced at the end of infection (7DPI). The marked increases in LBP, CD14 and haptoglobin were not correlated with the extent of the LPS response.


Assuntos
Infecções por Coronavirus/veterinária , Haptoglobinas/metabolismo , Lipopolissacarídeos/imunologia , Pneumopatias/veterinária , Coronavirus Respiratório Porcino/imunologia , Doenças dos Suínos/imunologia , Doenças dos Suínos/virologia , Proteínas de Fase Aguda/imunologia , Proteínas de Fase Aguda/metabolismo , Animais , Anticorpos Antivirais/sangue , Líquido da Lavagem Broncoalveolar/química , Líquido da Lavagem Broncoalveolar/citologia , Líquido da Lavagem Broncoalveolar/imunologia , Proteínas de Transporte/imunologia , Proteínas de Transporte/metabolismo , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/metabolismo , Infecções por Coronavirus/virologia , Citometria de Fluxo/veterinária , Vida Livre de Germes , Haptoglobinas/imunologia , Receptores de Lipopolissacarídeos/imunologia , Receptores de Lipopolissacarídeos/metabolismo , Lipopolissacarídeos/farmacologia , Pulmão/imunologia , Pulmão/virologia , Pneumopatias/imunologia , Pneumopatias/metabolismo , Pneumopatias/virologia , Glicoproteínas de Membrana/imunologia , Glicoproteínas de Membrana/metabolismo , Microscopia de Fluorescência/veterinária , Testes de Neutralização/veterinária , Suínos , Doenças dos Suínos/metabolismo
3.
Vet J ; 187(1): 48-53, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20097110

RESUMO

This study set out to investigate the cytokines and acute phase proteins (APPs) associated with the acute stages of experimentally-induced swine influenza virus (SIV) infection in 3-week-old, colostrum-deprived, caesarean-derived piglets. The piglets were inoculated intratracheally with 10(7.5) 50% egg infective dose [EID(50)] Swine/Belgium/1/98 (H1N1) SIV and were euthanased at time-points between 0 and 120h post-inoculation (PI). Broncho-alveolar lavage fluid (BALF), lung homogenates and sera were examined for inflammatory mediators by bioassay or ELISA. Interferon (IFN)-α, interleukin (IL)-6, IL-1 and tumour necrosis factor (TNF)-α peaked in BALF 24-30h PI, when virus titres and the severity of clinical signs were maximal. Whereas IFN-γ and IL-12, but not IL-18, increased in tandem in BALF, serum cytokine concentrations were either undetectable or were up to 100-fold lower. The APP C-reactive protein (CRP) and haptoglobin peaked 24h later than the cytokines and reached higher levels in serum than in BALF. In contrast, lipopolysaccharide (LPS)-binding protein (LBP) only increased in BALF. Lung virus titres tightly correlated with BALF IFN-α, IL-6, IL-1, TNF-α, IFN-γ and IL-12, as well as with serum IL-6, IFN-α and IFN-γ. Signs of disease correlated with the same cytokines in BALF and serum, as well as with BALF LBP and serum CRP. The findings suggest that IFN-γ and IL-12 play a role in the pathogenesis of SIV and that APPs are induced by cytokines. This influenza infection model may have value in assessing the therapeutic potential of cytokine antagonists.


Assuntos
Proteínas de Fase Aguda/biossíntese , Citocinas/biossíntese , Vírus da Influenza A Subtipo H1N1 , Infecções por Orthomyxoviridae/veterinária , Doenças dos Suínos/imunologia , Proteínas de Fase Aguda/imunologia , Animais , Líquido da Lavagem Broncoalveolar/imunologia , Líquido da Lavagem Broncoalveolar/virologia , Citocinas/imunologia , Vacinas contra Influenza/imunologia , Infecções por Orthomyxoviridae/imunologia , Suínos
4.
Vet J ; 188(2): 210-5, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-20409735

RESUMO

The objective of this study was to assess if lipoteichoic acid (LTA), produced by Staphylococcus aureus, exacerbates respiratory disease in porcine respiratory coronavirus (PRCV)-infected pigs, as has previously been shown with lipopolysaccharide. Piglets were inoculated with PRCV and 24h later with S. aureus LTA. Clinical signs, lung virus titres, inflammatory cells and cytokines in bronchoalveolar lavage fluid (BALF) were compared with those of animals in PRCV- and LTA-inoculated control groups. All PRCV-LTA-inoculated pigs except one developed severe respiratory disease, whereas clinical signs in the control groups were minimal or absent. Virus titres and grossly visible pulmonary lesions were similar in the PRCV-LTA- and PRCV-inoculated groups and were not detected in the LTA group. Neutrophil percentages in BALF were higher in the PRCV-LTA than in the PRCV group. There was no significant difference in interferon (IFN)-γ, interleukin (IL)-1, IL-6, IL-12/IL-23 and tumour necrosis factor (TNF)-α concentrations in BALF between the PRCV-LTA and PRCV groups, but levels of IL-6, IL-12/IL-23 and IFN-γ were higher in the PRCV-LTA-inoculated than in the LTA-inoculated controls. The findings suggest that the experimentally-induced respiratory disease was not mediated by cytokine over-production, but rather reflected the concerted action of particular cytokine interactions and/or as yet unidentified mediators. This is the first in vivo study to report the synergistic interaction between a virus and LTA in enhancing the severity of respiratory disease in the pig. Given that Gram-positive bacteria, capable of producing LTA, are commonly found in pig accommodation, the role of this compound in the development of the porcine respiratory disease complex requires further investigation.


Assuntos
Infecções por Coronavirus/veterinária , Lipopolissacarídeos/farmacologia , Coronavirus Respiratório Porcino/efeitos dos fármacos , Doenças Respiratórias/veterinária , Staphylococcus aureus/metabolismo , Doenças dos Suínos/patologia , Ácidos Teicoicos/farmacologia , Animais , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Citocinas/biossíntese , Feminino , Lipopolissacarídeos/biossíntese , Lipopolissacarídeos/imunologia , Masculino , Distribuição Aleatória , Doenças Respiratórias/patologia , Doenças Respiratórias/virologia , Índice de Gravidade de Doença , Suínos , Doenças dos Suínos/virologia , Ácidos Teicoicos/biossíntese , Ácidos Teicoicos/imunologia
5.
Res Vet Sci ; 88(1): 172-8, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19647281

RESUMO

Cytokines, especially interferon-alpha (IFN-alpha) are important in controlling influenza virus infections. To investigate the role of IFN-alpha in influenza, the swine IFN-alpha neutralizing monoclonal antibody (Ab) K9 was applied in a swine model of influenza A virus infection. First, the optimal dose and route for administration of the IFN-alpha neutralizing Abs was determined. Based on those results, the effect of the Abs on a swine influenza virus infection was investigated. Pigs were inoculated intratracheally with 10(6.0) mean egg infectious dose (EID(50)) A/Swine/Belgium/1/98 (H1N1) virus. At the time of challenge and 18 h later, they were injected intratracheally and intraperitoneally with a high dose of IFN-alpha neutralizing Abs or control Abs. The animals were euthanized at 0, 24, 30, 48 and 72 h after inoculation. At 24 and 30 h, IFN-alpha levels in broncho-alveolar lavage fluid of K9 recipient animals were strongly suppressed, and this coincided with reduced IL-6 and IL-12 levels. TNF-alpha and IL-1 levels were unaffected compared to those in the control Ab treated group. Importantly, the onset and peak of clinical symptoms in IFN-alpha neutralizing Abs treated animals were delayed by 24h, simultaneously with the suppression of IFN-alpha, but there was no obvious effect on virus replication and lung pathology. These results suggest an important role for IFN-alpha in IL-6 and IL-12 induction and a role of all three cytokines in the symptoms of swine influenza.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Interferon-alfa/fisiologia , Infecções por Orthomyxoviridae/veterinária , Doenças dos Suínos/virologia , Doença Aguda , Animais , Anticorpos Monoclonais/imunologia , Interleucina-12/fisiologia , Interleucina-6/fisiologia , Pulmão/imunologia , Pulmão/virologia , Infecções por Orthomyxoviridae/imunologia , Suínos/virologia , Doenças dos Suínos/imunologia , Fator de Necrose Tumoral alfa/fisiologia , Carga Viral/veterinária
6.
Vaccine ; 27(16): 2258-64, 2009 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-19428840

RESUMO

This study investigates the safety, immunogenicity and efficacy of different pox-vector vaccines expressing the haemagglutinin of a highly pathogenic (HP) H5N1 avian influenza virus (AIV) (A/chicken/Indonesia/7/03) in pigs. Pigs were vaccinated twice, with a 4-week interval, with a fowlpox (TROVAC), a canarypox (ALVAC), or a vaccinia (NYVAC) vector vaccine combined with an oil-in-water adjuvant, with the unadjuvanted NYVAC, or left unvaccinated. Six weeks after the second vaccination, all pigs were challenged intra-tracheally with low pathogenic (LP) H5N2 AIV A/chicken/Belgium/150/99. Sera were examined in haemagglutination inhibition (HI) tests against the H5N1 AIV from which the vaccine haemagglutinin derived, the challenge virus and the human A/Vietnam/1194/04 HPAIV. After challenge pigs were compared for H5N2 virus replication in the trachea and 4 lung lobes at 24 or 72h post-challenge. Vaccination was well tolerated by all animals. Antibody titres peaked 2 weeks after the second vaccination and were 2- to 4-fold higher against the vaccine virus than heterologous H5 viruses. The NYVAC and ALVAC adjuvanted vaccines consistently induced higher antibody titres than TROVAC or NYVAC without adjuvant. Following challenge, the H5N2 challenge virus was isolated from all unvaccinated pigs, while 19 out of 21 vaccinates showed complete virological protection. Pox-vector vaccines were safe, immunogenic and efficacious against challenge with a heterologous H5 AIV, offering an alternative to classical inactivated vaccines. It remains to be seen whether they would protect against a swine-adapted H5 virus, which may replicate 100-1000 times better than our challenge virus.


Assuntos
Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Virus da Influenza A Subtipo H5N1/imunologia , Vacinas contra Influenza/imunologia , Poxviridae/genética , Vacinas Sintéticas/imunologia , Animais , Anticorpos Antivirais/sangue , Vetores Genéticos , Testes de Inibição da Hemaglutinação , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Vírus da Influenza A Subtipo H5N2/imunologia , Vacinas contra Influenza/efeitos adversos , Suínos , Vacinação , Vacinas Sintéticas/efeitos adversos
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