RESUMO
In salmon farming, viruses are responsible for outbreaks that produce significant economic losses for which there is a lack of control tools other than vaccines. Type I interferon has been successfully used for treating some chronic viral infections in humans. However, its application in salmonids depends on the proper design of a vehicle that allows its massive administration, ideally orally. In mammals, administration of recombinant probiotics capable of expressing cytokines has shown local and systemic therapeutic effects. In this work, we evaluate the use of Lactococcus lactis as a type I Interferon expression system in Atlantic salmon, and we analyze its ability to stimulate the antiviral immune response against IPNV, in vivo and in vitro. The interferon expressed in L. lactis, even though it was located mainly in the bacterial cytoplasm, was functional, stimulating Mx and PKR expression in CHSE-214 cells, and reducing the IPNV viral load in SHK-1 cells. In vivo, the oral administration of this L. lactis producer of Interferon I increases Mx and PKR expression, mainly in the spleen, and to a lesser extent, in the head kidney. The oral administration of this strain also reduces the IPNV viral load in Atlantic salmon specimens challenged with this pathogen. Our results show that oral administration of L. lactis producing Interferon I induces systemic effects in Atlantic salmon, allowing to stimulate the antiviral immune response. This probiotic could have effects against a wide variety of viruses that infect Atlantic salmon and also be effective in other salmonids due to the high identity among their type I interferons.
Assuntos
Infecções por Birnaviridae/prevenção & controle , Proteínas de Peixes/metabolismo , Imunidade Inata , Vírus da Necrose Pancreática Infecciosa/patogenicidade , Interferon Tipo I/metabolismo , Lactococcus lactis/metabolismo , Probióticos , Salmo salar/microbiologia , Animais , Infecções por Birnaviridae/imunologia , Infecções por Birnaviridae/microbiologia , Infecções por Birnaviridae/virologia , Linhagem Celular , Proteínas de Peixes/genética , Pesqueiros , Interações Hospedeiro-Patógeno , Vírus da Necrose Pancreática Infecciosa/crescimento & desenvolvimento , Vírus da Necrose Pancreática Infecciosa/imunologia , Interferon Tipo I/genética , Lactococcus lactis/genética , Lactococcus lactis/imunologia , Proteínas de Resistência a Myxovirus/metabolismo , Salmo salar/genética , Salmo salar/imunologia , Salmo salar/virologia , Carga Viral , eIF-2 Quinase/metabolismoRESUMO
It has been demonstrated that vitamin D (Vit D) included in diets offers a beneficial effect by improving innate immune responses in chickens. However, its mechanisms of action and the effect on immunosuppressive pathogens, such as infectious bursal disease virus, are not yet known. In the present study, we have studied the immunomodulatory effect of Vit D on the innate immune response in 3 cell lines: fibroblast cells (DF-1), macrophages (HD11), and B cells (DT-40) infected with IBDV (intermediate vaccine) at 2 multiplicity of infections (MOI) (1 and 0.1). Genes associated with innate immune responses (TLR-3, TLR-21, MDA-5, MyD88, TRIF, IRF-7, INF-α, INF-ß, PKR, OAS, viperin, IL-1ß, IL-6, and IL-12) were evaluated at different time points (3, 6, 12, 24, and 36 h after infection, h.p.i). Virus production reached a maximum at 24 h.p.i., which was significantly (P < 0.05) higher in DF-1 cells, followed by HD-11 and DT-40 cells. Mainly in HD-11 cells, there was a significant (P < 0.05) effect of Vit D supplementation on receptors TLR-3, TLR-21, and MDA-5 after 12 h.p.i, independent of MOI. DT-40 cells showed the highest antiviral activity, with a significant (P < 0.05) effect on IRF-7, IFN-ß, OAS, and PKR gene expression, where expression of IRF-7 and IFN-ß correlated positively with Vit D supplementation, while OAS and PKR were independent of Vit D. Proinflammatory cytokines were significantly (P < 0.05) upregulated and found to be Vit D and MOI dependent. In conclusion, this study demonstrated the capacity of IBDV to trigger a strong innate immune response in chicken cells and contributes to the understanding of the activation pathways of innate immunity induced by IBDV and further shows the benefitial effect of Vit D supplementation as an immunomodulator.
Assuntos
Infecções por Birnaviridae , Imunidade Inata , Vírus da Doença Infecciosa da Bursa , Doenças das Aves Domésticas , Vitamina D , Animais , Infecções por Birnaviridae/imunologia , Infecções por Birnaviridae/veterinária , Linhagem Celular , Galinhas , Imunidade Inata/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Técnicas In Vitro , Vitamina D/farmacologiaRESUMO
Infectious bursal disease (IBD) is an acute, highly contagious immunosuppressive disease that affects young birds causing important economic losses in the poultry industry worldwide. Strict hygiene management together with effective vaccination programs are the most important strategies to prevent Infectious bursal disease virus entry in poultry production facilities. Hyperimmunisation of dams with inactivated vaccines just before the laying period provides passive immunity to the progeny that protects them during the critical first few weeks after hatching before vaccination with live attenuated virus takes place. In the present study, a safe and economic plant-based vaccine candidate against IBD intended for breeder hens was evaluated. We demonstrated that the recombinant immunogen is effective as booster for previously primed hens since it increases specific antibodies against VP2 that are transmitted to the offspring with titres and decay rate similar to those achieved by inactivated vaccine. Moreover, these maternally derived antibodies have virus neutralising activity and are able to confer protection against challenge in progeny, as evidenced by absence of bursal damage and low viral titres in this organ. Taking into account the disadvantages of inactivated vaccines as well as the benefits of plants as expression systems, such as time and cost efficiency, lower risk of contamination from animal pathogens and nearly unlimited scalability, a plant-based subunit IBD vaccine represents a viable alternative in the veterinary field.
Assuntos
Infecções por Birnaviridae/prevenção & controle , Plantas/metabolismo , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/prevenção & controle , Vacinas Atenuadas/uso terapêutico , Vacinas de Produtos Inativados/uso terapêutico , Vacinas Virais/uso terapêutico , Animais , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/metabolismo , Infecções por Birnaviridae/imunologia , Galinhas , Vírus da Doença Infecciosa da Bursa/imunologia , Vírus da Doença Infecciosa da Bursa/patogenicidade , Vacinas de Produtos Inativados/imunologiaRESUMO
Infectious pancreatic necrosis (IPN) is a viral disease with considerable negative impact on the rainbow trout (Oncorhynchus mykiss) aquaculture industry. The aim of the present work was to detect genomic regions that explain resistance to infectious pancreatic necrosis virus (IPNV) in rainbow trout. A total of 2,278 fish from 58 full-sib families were challenged with IPNV and 768 individuals were genotyped (488 resistant and 280 susceptible), using a 57K SNP panel Axiom, Affymetrix. A genome-wide association study (GWAS) was performed using the phenotypes time to death (TD) and binary survival (BS), along with the genotypes of the challenged fish using a Bayesian model (Bayes C). Heritabilities for resistance to IPNV estimated using genomic information, were 0.53 and 0.82 for TD and BS, respectively. The Bayesian GWAS detected a SNP located on chromosome 5 explaining 19% of the genetic variance for TD. The proximity of Sentrin-specific protease 5 (SENP5) to this SNP makes it a candidate gene for resistance against IPNV. In case of BS, a SNP located on chromosome 23 was detected explaining 9% of the genetic variance. However, the moderate-low proportion of variance explained by the detected marker leads to the conclusion that the incorporation of all genomic information, through genomic selection, would be the most appropriate approach to accelerate genetic progress for the improvement of resistance against IPNV in rainbow trout.
Assuntos
Resistência à Doença/genética , Doenças dos Peixes/virologia , Proteínas de Peixes/genética , Vírus da Necrose Pancreática Infecciosa/fisiologia , Oncorhynchus mykiss/genética , Animais , Teorema de Bayes , Infecções por Birnaviridae/genética , Infecções por Birnaviridae/imunologia , Infecções por Birnaviridae/mortalidade , Infecções por Birnaviridae/veterinária , Doenças dos Peixes/imunologia , Doenças dos Peixes/mortalidade , Proteínas de Peixes/imunologia , Estudo de Associação Genômica Ampla , Interações Hospedeiro-Patógeno/genética , Vírus da Necrose Pancreática Infecciosa/patogenicidade , Oncorhynchus mykiss/imunologia , Oncorhynchus mykiss/virologia , Polimorfismo de Nucleotídeo Único , Replicação Viral/fisiologiaRESUMO
Infectious bursal disease virus (IBDV) is the causative agent of a highly contagious immunosuppressive disease affecting young chickens. The recently described "distinct IBDV" (dIBDV) genetic lineage encompasses a group of worldwide distributed strains that share conserved genetic characteristics in both genome segments making them unique within IBDV strains. Phenotypic characterization of these strains is scarce and limited to Asiatic and European strains collected more than 15 years ago. The present study aimed to assess the complete and comprehensive phenotypic characterization of a recently collected South American dIBDV strain (1/chicken/URY/1302/16). Genetic analyses of both partial genome segments confirmed that this strain belongs to the dIBDV genetic lineage and that it is not a reassortant. Antigenic analysis with monoclonal antibodies indicated that this strain has a particular antigenic profile, similar to that obtained in a dIBDV strain from Europe (80/GA), which differs from those previously found in the traditional classic, variant and very virulent strains. Chickens infected with the South American dIBDV strain showed subclinical infections but had a marked bursal atrophy. Further analysis using Newcastle disease virus-immunized chickens, previously infected with the South American and European dIBDV strains, demonstrated their severe immunosuppressive effect. These results indicate that dIBDV strains currently circulating in South America can severely impair the immune system of chickens, consequently affecting the local poultry industry. Our study provides new insights into the characteristics and variability of this global genetic lineage and is valuable to determine whether specific control measures are required for the dIBDV lineage. Research Highlights A South American strain of the dIBDV lineage was phenotypically characterized. The strain produced subclinical infections with a marked bursal atrophy. Infected chickens were severely immunosuppressed. The dIBDV strains are antigenically divergent from other IBDV lineages.
Assuntos
Infecções por Birnaviridae/veterinária , Galinhas/virologia , Vírus da Doença Infecciosa da Bursa/genética , Vírus da Doença Infecciosa da Bursa/imunologia , Doenças das Aves Domésticas/virologia , Animais , Infecções por Birnaviridae/imunologia , Infecções por Birnaviridae/virologia , Galinhas/imunologia , Genótipo , Imunogenicidade da Vacina , Terapia de Imunossupressão/veterinária , Vírus da Doença Infecciosa da Bursa/isolamento & purificação , Vírus da Doença Infecciosa da Bursa/patogenicidade , Fenótipo , Doenças das Aves Domésticas/imunologia , VirulênciaRESUMO
In this study, the immune response induced by a mixture of polysaccharide and nucleic acid extracted from Bacillus Calmette-Guerin (BCG) was evaluated in chickens inoculated with infectious bursal disease virus (IBDV) vaccine. After the mixture was injected intramuscularly at a dose of 0.075, 0.15 or 0.3 mg·kg(-1)·day(-1) for 3 days, the 14-day-old chickens were inoculated with the attenuated IBDV vaccine via intranasal and ocular routes. The relative weight of bursa of Fabricius (BF) and thymus, the serum IBD antibody titer, the CD4+/CD8+ ratio, and the concentrations of IFN-γ, IL-2 and IL-6 in peripheral blood were investigated on days 5, 15 and 25. The IBD antibody titer in BCG-treated groups was higher than in the negative control and only IBD-vaccinated chickens, indicating that the mixture of BCG can significantly enhance chicken humoral response. CD4+/CD8+ and the secretions of IFN-γ, IL-2 and IL-6 were also clearly increased compared with that in the negative control and IBD-vaccinated chickens, indicating that the mixture can also enhance the cell-mediated immune response. The results also showed that the relative weights of BF and thymus increased after chickens were inoculated with BCG, indicating that the BCG mixture can clearly enhance the immunity of IBD-vaccine and can be expected to be viewed as a candidate for a new type of immune adjuvant.
Assuntos
Vacina BCG/imunologia , Infecções por Birnaviridae/veterinária , Vírus da Doença Infecciosa da Bursa/imunologia , Ácidos Nucleicos/imunologia , Polissacarídeos/imunologia , Doenças das Aves Domésticas/imunologia , Adjuvantes Imunológicos/farmacologia , Animais , Anticorpos Antivirais/sangue , Vacina BCG/química , Vacina BCG/farmacologia , Infecções por Birnaviridae/imunologia , Galinhas/imunologia , Vírus da Doença Infecciosa da Bursa/metabolismo , Masculino , Ácidos Nucleicos/isolamento & purificação , Ácidos Nucleicos/farmacologia , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Doenças das Aves Domésticas/terapia , Distribuição Aleatória , Vacinas Atenuadas/imunologia , Vacinas Atenuadas/farmacologia , Vacinas de DNA/administração & dosagem , Vacinas de DNA/farmacologia , Vacinas Virais/imunologia , Vacinas Virais/farmacologiaAssuntos
Infecções por Birnaviridae/veterinária , Vírus da Varíola dos Canários/imunologia , Vírus da Doença Infecciosa da Bursa/genética , Doenças das Aves Domésticas/imunologia , Proteínas Estruturais Virais/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Antígenos Virais/genética , Antígenos Virais/imunologia , Infecções por Birnaviridae/imunologia , Infecções por Birnaviridae/prevenção & controle , Bolsa de Fabricius/diagnóstico por imagem , Bolsa de Fabricius/patologia , Vírus da Varíola dos Canários/genética , Vírus da Varíola dos Canários/metabolismo , Galinhas , Vetores Genéticos , Doenças das Aves Domésticas/prevenção & controle , Doenças das Aves Domésticas/virologia , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Proteínas Estruturais Virais/biossíntese , Proteínas Estruturais Virais/genética , Vacinas Virais/administração & dosagem , Vacinas Virais/genéticaRESUMO
The immune response elicited by the oral inoculation of an intermediate strain of infectious bursal disease virus was studied in chickens. A strong over expression of IL-6, IL-8, IFNα and IFNγ was observed in bursa at 3 days post inoculation together with an increase in splenic NO2 release. An influx of T-lymphocytes was also detected.
Assuntos
Animais , Infecções por Birnaviridae/veterinária , Galinhas , Vírus da Doença Infecciosa da Bursa/imunologia , Doenças das Aves Domésticas/imunologia , Administração Oral , Infecções por Birnaviridae/imunologia , Bolsa de Fabricius/patologia , Citocinas/análise , Citocinas/genética , Perfilação da Expressão Gênica , Óxido Nítrico/análise , Baço/patologia , Linfócitos T/imunologiaRESUMO
The immune response elicited by the oral inoculation of an intermediate strain of infectious bursal disease virus was studied in chickens. A strong over expression of IL-6, IL-8, IFNα and IFNγ was observed in bursa at 3 days post inoculation together with an increase in splenic NO2 release. An influx of T-lymphocytes was also detected.
Assuntos
Animais , Infecções por Birnaviridae/veterinária , Galinhas , Vírus da Doença Infecciosa da Bursa/imunologia , Doenças das Aves Domésticas/imunologia , Administração Oral , Infecções por Birnaviridae/imunologia , Bolsa de Fabricius/patologia , Citocinas/análise , Citocinas/genética , Perfilação da Expressão Gênica , Óxido Nítrico/análise , Baço/patologia , Linfócitos T/imunologiaRESUMO
Canarypox viruses (CNPV) carrying the coding sequence of VP2 protein from infectious bursal disease virus (IBDV) were obtained. These viruses were able to express VP2 protein in vitro and to induce IBDV-neutralizing antibodies when inoculated in specific pathogen-free chickens demonstrating that CNPV platform is usefulness to develop immunogens for chickens.