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1.
Arch Virol ; 164(12): 3007-3017, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31598846

RESUMO

Classical swine fever (CSF) is an important viral disease of domestic pigs and wild boar. The structural proteins E2 and Erns of classical swine fever virus (CSFV), which participate in the attachment of the virion to the host cell surface and its subsequent entry, are immunogenic. The E2 and Erns proteins are used for diagnosis and the development of vaccines against CSFV infection in swine. Newcastle disease virus (NDV) has been successfully used as a viral vector to express heterologous proteins. In the present study, the E2 and Erns proteins of CSFV were expressed in cell culture as well as embryonated chicken eggs, using recombinant NDV (rNDV). Rescued rNDV expressing the E2 and Erns proteins induced the production of CSFV-neutralizing antibodies upon intranasal vaccination of pigs. Serum samples from vaccinated animals were found to neutralize both homologous and heterologous CSFV strains. Furthermore, rNDV expressing the E2 and Erns proteins of CSFV was used to develop an indirect ELISA, which was used to measure the the antibody titers of randomly collected serum samples. The results suggested that the ELISA based on rNDV-expressed E2 and Erns proteins could be used to screen for CSFV infections. This study shows that rNDV-based expression of CSFV antigens is potentially applicable for development of vaccines and diagnostic tests for CSFV infection. This approach could be an economically favorable alternative to the existing vaccine and diagnostics for CSFV in pigs.


Assuntos
Vírus da Febre Suína Clássica/imunologia , Peste Suína Clássica/diagnóstico , Testes Diagnósticos de Rotina/métodos , Ensaio de Imunoadsorção Enzimática/métodos , Glicoproteínas de Membrana/sangue , Vírus da Doença de Newcastle/genética , Animais , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Peste Suína Clássica/sangue , Peste Suína Clássica/imunologia , Peste Suína Clássica/virologia , Vírus da Febre Suína Clássica/genética , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/imunologia , Vírus da Doença de Newcastle/imunologia , Recombinação Genética , Suínos
2.
Acta Vet Scand ; 61(1): 41, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31455410

RESUMO

BACKGROUND: Villegas-Glisson/University of Georgia (VG/GA) strain of Newcastle disease virus (NDV) is recommended for the initial vaccination of commercially reared turkey poults. However, the vaccine-induced antibody responses have not been studied in this species. The level of systemic humoral immune responses against the NDV was investigated in commercial turkey poults vaccinated with the VG/GA vaccine. One hundred eighty-two hybrid strain of turkey poults (Meleagris gallopavo) were divided randomly into vaccinated and unvaccinated groups. The vaccinated group was given the VG/GA vaccine at 10 and 20 days of age. To investigate the vaccine immunity, the level of specific IgY and IgA in serum samples were determined using ELISA and haemagglutination inhibition assays (HI). The biological half-life of maternal antibodies was also determined before the immunization. RESULTS: VG/GA-specific antibodies were detected in the vaccinated turkey poults and were significantly higher in the vaccinated group compared to the unvaccinated group. IgY and IgA antibodies showed a significant increase in titers 14 days after the second vaccination and reached a peak on day 35 of age. The correlation coefficient and intra-rater reliability showed a significant correlation between the HI titers and IgY/IgA ELISA values. Maternal IgY and IgA levels were found to decline in the serum with half-lifes of 7.68 ± 2.35 and 2.18 ± 0.82 days, respectively. CONCLUSIONS: Enterotropic lentogenic VG/GA vaccine induced a marked humoral immune response against the NDV in turkey poults. The positive correlation between IgY and IgA highlights the role of these two antibody classes in controlling the Newcastle disease in turkey poults.


Assuntos
Imunidade Humoral/imunologia , Doença de Newcastle/imunologia , Vírus da Doença de Newcastle/imunologia , Doenças das Aves Domésticas/imunologia , Perus , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/sangue , Doença de Newcastle/prevenção & controle , Doenças das Aves Domésticas/prevenção & controle
3.
Vet Res Commun ; 43(4): 225-230, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31446518

RESUMO

Toll-like receptors (TLRs) are pattern recognition receptors (PRRs) that mediate first line of host defence to pathogens. TLR agonists are potent immunostimulatory agents that help to prime a robust adaptive immune response. In the present study, adjuvant potential of Poly I:C and lipopolysaccharide (LPS) were evaluated with live Newcastle disease virus (NDV) vaccine. Cornish chickens were immunized with live Newcastle disease virus (NDV) vaccine (R2B-mesogenic strain) adjuvanted either with Poly I:C (TLR3 agonist) or LPS-TLR4 agonist and both. Humoral Immune response to ND vaccine was evaluated through haemagglutination inhibition (HI) test and ELISA, while the cellular immune response (CMI) was quantified by lymphocyte transformation test (LTT). IL-1ß cytokine mRNA levels in spleen tissue were also quantified by real time PCR. The results suggest that TLR3 and TLR4 agonists are an efficient immune-stimulators separately, as LPS co-administered group has shown significantly higher serum titre on second week post-immunization and Poly I:C group on third week post-immunization both by HI and ELISA (P < 0.01), however, the combined administration of both LPS and Poly I:C did not give any complementary effect on serum titre. There were no significant differences in stimulation indices (SI) and IL-1ß cytokine levels between groups at different intervals post-immunization. Hence, TLR agonists LPS followed by Poly I:C could be used as adjuvant to enhance the immune response to NDV vaccine in chicken.


Assuntos
Imunidade Humoral/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Doença de Newcastle/imunologia , Poli I-C/farmacologia , Receptor 3 Toll-Like/agonistas , Receptor 4 Toll-Like/agonistas , Vacinas Virais/imunologia , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/farmacologia , Animais , Galinhas , Ensaio de Imunoadsorção Enzimática , Imunidade Celular/efeitos dos fármacos , Lipopolissacarídeos/administração & dosagem , Vírus da Doença de Newcastle/imunologia , Poli I-C/administração & dosagem
4.
Genes (Basel) ; 10(7)2019 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-31319636

RESUMO

Newcastle Disease (ND) is a continuing global threat to domestic poultry, especially in developing countries, where severe outbreaks of velogenic ND virus (NDV) often cause major economic losses to households. Local chickens are of great importance to rural family livelihoods through provision of high-quality protein. To investigate the genetic basis of host response to NDV, three popular Tanzanian chicken ecotypes (regional populations) were challenged with a lentogenic (vaccine) strain of NDV at 28 days of age. Various host response phenotypes, including anti-NDV antibody levels (pre-infection and 10 days post-infection, dpi), and viral load (2 and 6 dpi) were measured, in addition to growth rate. We estimated genetic parameters and conducted genome-wide association study analyses by genotyping 1399 chickens using the Affymetrix 600K chicken SNP chip. Estimates of heritability of the evaluated traits were moderate (0.18-0.35). Five quantitative trait loci (QTL) associated with growth and/or response to NDV were identified by single-SNP analyses, with some regions explaining ≥1% of genetic variance based on the Bayes-B method. Immune related genes, such as ETS1, TIRAP, and KIRREL3, were located in regions associated with viral load at 6 dpi. The moderate estimates of heritability and identified QTL indicate that NDV response traits may be improved through selective breeding of chickens to enhance increased NDV resistance and vaccine efficacy in Tanzanian local ecotypes.


Assuntos
Galinhas/genética , Galinhas/virologia , Ecótipo , Interações Hospedeiro-Patógeno/genética , Doença de Newcastle/virologia , Vírus da Doença de Newcastle , Doenças das Aves Domésticas/virologia , Animais , Galinhas/imunologia , Biologia Computacional/métodos , Genoma , Estudo de Associação Genômica Ampla , Genômica/métodos , Genótipo , Interações Hospedeiro-Patógeno/imunologia , Doença de Newcastle/imunologia , Vírus da Doença de Newcastle/imunologia , Fenótipo , Polimorfismo de Nucleotídeo Único , Doenças das Aves Domésticas/imunologia , Locos de Características Quantitativas
5.
Microb Pathog ; 135: 103621, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31310831

RESUMO

Astragalus polysaccharides (APS) are a traditional Chinese medicine with a therapeutic effect by enhancing immune function; however, the underlying functional mechanism is still unclear. The aim of the present study was to determine the effect of oral administration of APS on jejunum mucosal immunity in chickens vaccinated against Newcastle disease (ND). One-day-old Hy-Line male chickens were divided into five groups of 20 chicks each: three APS groups, one vaccinated control (VC) group and one non-vaccinated negative control (NC) group. On d 10, the APS groups were orally administered 0.5 mL of APS at doses of 1 mg/mL (APSL), 2 mg/mL (APSM) and 4 mg/mL (APSH) daily for 4 consecutive days. The chicks in the control groups were administered 0.5 mL saline for those 4 days. All groups except NC were administered a ND virus (NDV) vaccine on day 14. The jejunum was removed from 4 randomly selected chickens of each group at 1, 7, 14 and 28 days after vaccination. The jejunal villus height (VH) and crypt depth (CD) were measured and the VH:CD ratio calculated. Immunohistochemistry was used to analyze the differences of IgA+ cells in the jejunum. NDV specific secretory IgA (sIgA) levels in jejunal contents were detected using an indirect ELISA. At most time points, VH:CD ratios, number of IgA+ cells, and sIgA levels were significantly higher in the APS groups than those in VC and NC groups, but there were little differences among the three doses of APS groups. These results indicate that oral administration of APS could enhance the intestinal mucosal immune function of chickens, and APS could be used as a vaccine enhancer.


Assuntos
Astrágalo (Planta)/química , Galinhas/imunologia , Imunidade nas Mucosas/efeitos dos fármacos , Jejuno/efeitos dos fármacos , Doença de Newcastle/imunologia , Polissacarídeos/administração & dosagem , Vacinação/veterinária , Administração Oral , Animais , Modelos Animais de Doenças , Imunoglobulina A Secretora , Jejuno/patologia , Masculino , Medicina Tradicional Chinesa , Vírus da Doença de Newcastle/imunologia , Extratos Vegetais/administração & dosagem
6.
Poult Sci ; 98(9): 3548-3556, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31220864

RESUMO

Vaccination with a live bivalent vaccine of Newcastle disease virus (NDV) and infectious bronchitis virus (IBV) is a routine practice in poultry industry in China. This study was designed to evaluate ginseng stem-leaf saponins (GSLS) in combination with selenium (Se) for their adjuvant effect on the immune response to vaccination against NDV and IBV in chickens. A live bivalent vaccine of NDV and IBV was diluted in saline solution containing GSLS or Se or both and used to immunize chickens via a intraocular-and-intranasal route. Results showed that GSLS promoted significantly higher NDV- and IBV-specific antibody responses with the highest antibody response detected in GSLS-Se group. The increased antibody was capable of neutralizing NDV and IBV. In addition, GSLS-Se enhanced lymphocyte proliferation and production of IFN-γ and IL-4. More importantly GSLS-Se was found to promote early production and prolong the duration of the antibody responses. In order to improve the efficacy of vaccination in chicken flocks, the diluent containing GSLS-Se deserves further studies to evaluate its effect on other chicken vaccines.


Assuntos
Galinhas , Panax/química , Doenças das Aves Domésticas/imunologia , Saponinas/farmacologia , Selênio/farmacologia , Vacinas Virais/imunologia , Adjuvantes Imunológicos/farmacologia , Animais , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/veterinária , Imunidade , Vírus da Bronquite Infecciosa/imunologia , Doença de Newcastle/imunologia , Vírus da Doença de Newcastle/imunologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Saponinas/química , Vacinas Atenuadas/imunologia
7.
Poult Sci ; 98(10): 4416-4425, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31065721

RESUMO

In commercial layer poultry farming, molt induction is an important tool used by egg producers to prolong the production cycle of laying hens. Conventional molt induction programs involve total feed withdrawal, which raises questions about animal welfare and increased infection susceptibility. The high incidence of paratyphoid salmonellosis infections in commercial poultry farming is still an important health challenge because in addition to affecting the birds, such infections also cause public health problems. In this context, experiments were performed with laying hens at 79 wk of age to compare the conventional forced molting method (fasting) with an alternative method (free wheat bran supply) and determine their effect on the persistence of vaccine antibodies against Newcastle disease, the control and reduction of experimentally inoculated Salmonella Enteritidis, and the performance and egg quality of hens. A reduction (P < 0.05) of Salmonella Enteritidis in the crop and lower production of corticosterone were observed in the birds that received wheat bran compared with those subjected to total fasting. Moreover, a better performance (P < 0.05) with regard to egg production, egg mass, and feed conversion/kg and dozen eggs was observed in the hens that received the alternative treatment compared to the conventional forced molting method. Thus, the use of wheat bran for forced molting was found to be feasible and met the welfare needs of the hens.


Assuntos
Criação de Animais Domésticos/métodos , Galinhas , Corticosterona/sangue , Muda , Doenças das Aves Domésticas/prevenção & controle , Reprodução/efeitos dos fármacos , Salmonelose Animal/prevenção & controle , Ração Animal/análise , Animais , Anticorpos Antivirais/sangue , Dieta/veterinária , Fibras na Dieta/administração & dosagem , Feminino , Privação de Alimentos/fisiologia , Vírus da Doença de Newcastle/imunologia , Óvulo/efeitos dos fármacos , Óvulo/fisiologia , Doenças das Aves Domésticas/microbiologia , Distribuição Aleatória , Salmonelose Animal/microbiologia , Salmonella enteritidis/fisiologia
9.
J Appl Microbiol ; 127(2): 396-405, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31075179

RESUMO

AIMS: This study was designed to investigate, in an in vivo setting, the effects of single and combined infections with either Mycoplasma gallisepticum (MG) and/or Escherichia coli on the chicken immune response induced by Newcastle disease virus (NDV) vaccine. METHODS AND RESULTS: Humoral immunity was measured through detection of NDV antibody and anti-NDV IgG titres using haemagglutination-inhibition test and enzyme-linked immunosorbent assay, respectively. In addition, the expression levels of pro-inflammatory cytokines' genes (interleukin (IL) 6, IL4 and interferon (IFN) γ) were analysed using quantitative reverse transcription PCR. Significant (P < 0·05) results in all immunological parameters were detected in the vaccinated noninfected chicken group in comparison with those in groups exposed to bacterial infections. Bacterial infection along with vaccination hampered the NDV antibodies production and reduced the vaccine upregulated cytokine genes. The vaccinated mixed infection group reported lower antibody titres and cytokines expression levels compared to those in the single infection groups. All the previously enhanced immunological parameters reflected the maximum protection post challenge with velogenic viscerotropic NDV in the vaccinated noninfected chicken group. CONCLUSIONS: These findings provide novel insights into the immunosuppression activities of MG and E. coli infection in chickens vaccinated against NDV. SIGNIFICANCE AND IMPACT OF THE STUDY: This study hopes to provide a better insight to the immunosuppressive action of bacterial pathogens in chickens. This will help to improve biosecurity strategies during NDV vaccination in the future.


Assuntos
Galinhas/imunologia , Infecções por Escherichia coli/veterinária , Infecções por Mycoplasma/veterinária , Mycoplasma gallisepticum , Vírus da Doença de Newcastle/imunologia , Doenças das Aves Domésticas/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/biossíntese , Coinfecção/veterinária , Citocinas/genética , Citocinas/metabolismo , Infecções por Escherichia coli/imunologia , Imunidade Humoral , Infecções por Mycoplasma/imunologia , Doenças das Aves Domésticas/microbiologia
10.
Poult Sci ; 98(10): 4426-4432, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31111922

RESUMO

Currently, both goose astrovirus (GoAstV) and goose-origin Newcastle disease virus (NDV) are widely infectious agents for goslings. There is no vaccine for GoAstV. Capsid protein can elicit a neutralizing antibody in human astroviruses (HAstV). Molecular analysis of the genomic region encoding the capsid protein(ORF2) of goose astrovirus has revealed that it contains neutralizing epitopes. Goose-origin NDV is also an infectious agent. A wide range of NDV strains exist that can be commonly used as vaccine vectors. In the present study, the fusion protein cleavage site RRQKR↓F in a backbone of the virulent goose-origin NDV SH-12 was changed into an avirulent motif GRQGR↓L. The modified goose-origin NDV recombinant vaccine virus expressing the Capsid protein (Cap) of GoAstV was generated as a bivalent vaccine using a reverse-genetics approach. The recombinant virus, rNDV/GoAstV-Cap, was attenuated and similar growth dynamics, cytopathic effects, and virus titers in vitro were maintained when compared to the LaSota strain. Expression of the GoAstV-Cap protein in rNDV/GoAstV-Cap infected cells was detected by an immunofluorescence assay and Western blotting. Goslings inoculated with rNDV/GoAstV-Cap showed no apparent signs of disease and induced GoAstV-Cap-specific immune responses and NDV-specific serum antibody responses to a LaSota vaccination control. Complete protection against a pathogenic GoAstV challenge and avelogenic NDV challenge was conferred. The results of the study suggested that rNDV/GoAstV-Cap viruses have the potential to be the safe, stable, and effective bivalent vaccines.


Assuntos
Avastrovirus/imunologia , Gansos , Doença de Newcastle/terapia , Vírus da Doença de Newcastle/imunologia , Doenças das Aves Domésticas/terapia , Vacinas Virais/imunologia , Animais , Proteínas do Capsídeo/imunologia , Doença de Newcastle/virologia , Doenças das Aves Domésticas/virologia
11.
Poult Sci ; 98(10): 4441-4448, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31111928

RESUMO

This work was designed to study the dynamics of transmission of Newcastle disease virus (NDV), genotype VIId, from Muscovy ducks (Cariana moscata) infected either by intramuscular (IM) or intranasal (IN) inoculation, to in-contact broiler chickens (Gallus gallus). IM-infected Muscovy ducks (G1d) exhibited only 5% mortality, and the concentration of virus shed from the cloaca was greater and for longer period than virus shed from the trachea. In contrast, IN-infected ducks (G2d) exhibited no mortality, and virus shedding from the trachea was higher than that from the cloaca starting from 4 days post infection (dpi) and continued up to 16 dpi, while in IM-infected ducks (G1d), tracheal shedding stopped at 11 dpi. Chickens in contact with IM-infected and IN-infected ducks, G1c and G2c, respectively, not only developed severe clinical symptoms and death (80% and 20% mortality, respectively), but also shed the virus at higher concentrations than infected ducks. G1c chickens had higher viral shedding titers in both the trachea and cloaca than G2c chickens until 11 dpi. All broiler chickens infected by IM route (G3c) died, while the IN route of infection resulted in lower mortality (70%) in G4c. Generally, all IM-infected birds produced an earlier and higher level of NDV hemagglutination inhibition (HI) antibody titer, along with higher rates and shorter periods of viral shedding than those infected by the intranasal route. Our conclusion is that Muscovy ducks are efficient carriers of NDV-genotype VIId and transmit the virus to contact chickens.


Assuntos
Galinhas , Patos , Doença de Newcastle/transmissão , Vírus da Doença de Newcastle/imunologia , Doenças das Aves Domésticas/transmissão , Animais , Genótipo , Doença de Newcastle/virologia , Vírus da Doença de Newcastle/genética , Doenças das Aves Domésticas/virologia
12.
Microb Pathog ; 133: 103556, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31128172

RESUMO

To investigate cytokine expression in chicken embryo fibroblast (CEF) cells, a virulent avian avulavirus 1 (AAvV-1) strain called SG10 that rapidly causes 100% mortality in its host, and a vaccine strain (La Sota) were characterized. Real-time quantitative PCR was performed on RNA samples from CEF cells, which were collected at 0, 24, 48 and 72 h post-infection. The dynamic expression patterns of ten cytokines (TNF-α, IFN-α, IFN-ß, IL-1ß, IL-2, IL-6, IL-10, IL-13, IL-15 and IL-18) were investigated. The results showed that infection with lentogenic La Sota induced significantly higher levels of the antiviral cytokines IFN-α and IFN-ß, proinflammatory cytokines IL-2, IL-15 and IL-18, and the anti-inflammatory cytokine IL-10, than did infection with virulent SG10. Furthermore, the SG10 strain induced dramatically higher levels of the inflammatory cytokine IL-6 than those observed in cells infected with La Sota. However, the expression patterns of the other cytokines that were tested did not show any obvious trends or statistically significant differences between cells infected with the virulent and avirulent strains. These data show that infection with lentogenic La Sota induced more effective immune responses and anti-viral effects than did infection with virulent SG10 in CEFs. Our data provide distinct expression patterns of IFNs and proinflammatory and anti-inflammatory cytokines to AAvV-1 by virulence in CEF cells.


Assuntos
Embrião de Galinha/imunologia , Citocinas/metabolismo , Fibroblastos/imunologia , Doença de Newcastle/imunologia , Vírus da Doença de Newcastle/imunologia , Animais , Galinhas/imunologia , Galinhas/metabolismo , Citocinas/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/imunologia , Doença de Newcastle/virologia , Vacinas Virais/imunologia
13.
Vet Microbiol ; 232: 146-150, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31030839

RESUMO

Newcastle disease virus (NDV) is a major threat to poultry worldwide. Virulent Newcastle disease virus infection can cause 100% morbidity and mortality in chickens. Vaccination is the most effective way to prevent and control NDV outbreaks in poultry. Previously, we demonstrated that a duck enteritis virus (DEV) vaccine strain is a promising vector to generate recombinant vaccines in chickens. Here, we constructed two recombinant DEVs expressing the F protein (rDEV-F) or HN protein (rDEV-HN) of NDV. We then evaluated the protective efficacy of these recombinant DEVs in specific-pathogen-free chickens. rDEV-F induced 100% protection of chickens from lethal NDV challenge after a single dose of 104 TCID50, whereas rDEV-HN did not induce effective protection. rDEV-F may therefore serve as a promising vaccine candidate for chickens. This is the first report of a DEV-vectored vaccine providing robust protection against lethal NDV infection in chickens.


Assuntos
Mardivirus/genética , Doença de Newcastle/prevenção & controle , Doenças das Aves Domésticas/prevenção & controle , Proteínas Virais de Fusão/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais , Galinhas/imunologia , Galinhas/virologia , Patos/virologia , Proteína HN/genética , Proteína HN/imunologia , Doença de Newcastle/imunologia , Vírus da Doença de Newcastle/genética , Vírus da Doença de Newcastle/imunologia , Doenças das Aves Domésticas/virologia , Organismos Livres de Patógenos Específicos , Vacinação , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia , Proteínas Virais de Fusão/genética , Vacinas Virais/administração & dosagem
14.
Poult Sci ; 98(8): 3150-3157, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30919905

RESUMO

Immunoglobulins, which are passed vertically from hens to their progeny, are first present in the eggs but with time also in the developing embryos and eventually in the serum of hatching chicks, and have protective function during embryogenesis and in the first few weeks of birds' life, before the immune system becomes fully efficient. Considering the above fact, the aim of this study was to determine total levels of IgM and IgY as well as specific IgY antibody titers against selected pathogens in the serum of breeder turkeys and their progeny, as well as in egg yolks and egg whites. Study results demonstrated that the level of IgY antibodies in the serum of turkey breeder hens reached 22.04 mg/mL on average in the whole egg laying cycle. In addition, the mean transfer percentage of IgY antibodies from turkey layers to their progeny reached approximately 31.4%, but the level of this transfer differed depending on pathogen character and accounted for 33.2%, 51.9%, 45.1%, and 44.3% in the case of antibodies against avian metapneumoviruses, Newcastle disease virus, Ornithobacterium rhinortacheale, and Pasteurella multocida, respectively. Antibody percentage transfer differed also as affected by the stage of the egg production cycle. Study results confirmed the earlier observed dependency concerning the class of antibodies transferred to eggs from laying hens, and while the IgY were mainly detected in the egg yolk extracts, the IgM were found only in egg white extracts; in comparison to IgY, the IgM antibodies were not transferred to the serum of turkey poults. To our best knowledge, this is the first study that describes in detail the phenomenon of maternal antibody transfer in turkeys.


Assuntos
Anticorpos/análise , Imunidade Materno-Adquirida , Óvulo/imunologia , Doenças das Aves Domésticas/imunologia , Animais , Feminino , Imunoglobulina G/sangue , Imunoglobulinas/sangue , Metapneumovirus/imunologia , Vírus da Doença de Newcastle/imunologia , Ornithobacterium/imunologia , Pasteurella multocida/imunologia , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/virologia , Perus/imunologia
15.
Trop Anim Health Prod ; 51(5): 1033-1048, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30877525

RESUMO

Newcastle disease (ND) infects wild birds and poultry species worldwide, severely impacting the economics of the poultry industry. ND is especially problematic in Latin America (Mexico, Colombia, Venezuela, and Peru) where it is either endemic or re-emerging. The disease is caused by infections with one of the different strains of virulent avian Newcastle disease virus (NDV), recently renamed Avian avulavirus 1. Here, we describe the molecular epidemiology of Latin American NDVs, current control and prevention methods, including vaccines and vaccination protocols, as well as future strategies for control of ND. Because the productive, cultural, economic, social, and ecological conditions that facilitate poultry endemicity in South America are similar to those in the developing world, most of the problems and control strategies described here are applicable to other continents.


Assuntos
Galinhas , Doença de Newcastle , Vírus da Doença de Newcastle/imunologia , Doenças das Aves Domésticas , Vacinação/veterinária , Vacinas Virais/administração & dosagem , Animais , América Latina/epidemiologia , Doença de Newcastle/epidemiologia , Doença de Newcastle/prevenção & controle , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/prevenção & controle
16.
J Nanobiotechnology ; 17(1): 35, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30823927

RESUMO

BACKGROUND: Sensitive and specific antibodies can be used as essential probes to develop competitive enzyme-linked immunosorbent assay (cELISA). However, traditional antibodies are difficult to produce, only available in limited quantities, and ineffective as enzymatic labels. Nanobodies, which are single-domain antibodies (sdAbs), offer an alternative, more promising tool to circumvent these limitations. In the present work, a cELISA using nanobody-horseradish peroxidase (HRP) fusion protein firstly designed as a probe was developed for detecting anti-Newcastle disease virus (NDV) antibodies in chicken sera. RESULTS: In the study, a platform for the rapid and simple production of nanobody-HRP fusion protein was constructed. First, a total of 9 anti-NDV-NP protein nanobodies were screened from a immunised Bactrian camel. Then, the Nb5-HRP fusions were produced with the platform and used for the first time as sensitive reagents for developing cELISA to detect anti-NDV antibodies. The cut-off value of the cELISA was 18%, and the sensitivity and specificity were respectively 100% and 98.6%. The HI test and commercial ELISA kit (IDEXX) separately agreed 97.83% and 98.1% with cELISA when testing clinical chicken sera and both agreed 100% when testing egg yolks. However, for detecting anti-NDV antibodies in the sequential sera from the challenged chickens, cELISA demonstrated to be more sensitive than the HI test and commercial ELISA kit. Moreover, a close correlation (R2 = 0.914) was found between the percent competitive inhibition values of cELISA and HI titers. CONCLUSIONS: A platform was successfully designed to easily and rapidly produce the nanobody-HRP fusion protein, which was the first time to be used as reagents for establishing cELISA. Results suggest that the platform supports the development of a cELISA with high sensitivity, simplicity, and rapid detection of anti-NDV antibodies. Overall, we believe that the platform based on nanobody-HRP fusions can be widely used for future investigations and treatment other diseases and viruses.


Assuntos
Anticorpos Antivirais/sangue , Ensaio de Imunoadsorção Enzimática , Vírus da Doença de Newcastle/imunologia , Anticorpos de Domínio Único/imunologia , Animais , Anticorpos Antivirais/isolamento & purificação , Camelus , Galinhas , Escherichia coli , Biblioteca Gênica , Células HEK293 , Peroxidase do Rábano Silvestre/química , Humanos , Proteínas Recombinantes/química , Sensibilidade e Especificidade
17.
Viruses ; 11(3)2019 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-30871190

RESUMO

Infectious bronchitis virus (IBV) and Newcastle disease virus (NDV) are two poultry pathogens seriously affecting the poultry industry. Here, IBV S1 and the ectodomain of NDV F proteins were separately linked with the trans-membrane and carboxy-terminal domain of IBV S protein (STMCT), composing rS and rF; thus, a novel chimeric infectious bronchitis-Newcastle disease (IB-ND) virus-like particles (VLPs) vaccine containing the rS, rF, and IBV M protein was constructed. Under the transmission electron microscope (TEM), VLPs possessing similar morphology to natural IBV were observed. To evaluate the immunogenicity of chimeric IB-ND VLPs, specific pathogen-free (SPF) chickens were immunized with three increasing doses (50, 75, and 100 µg protein of VLPs). Results of ELISAs detecting IBV and NDV specific antibodies and IL-4 and IFN-γ T cell cytokines indicated that vaccination with chimeric IB-ND VLPs could efficiently induce humoral and cellular immune responses. In the challenge study, chimeric IB-ND VLPs (100 µg protein) provided 100% protection against IBV or NDV virulent challenge from death, and viral RNA levels in tissues and swabs were greatly reduced. Collectively, chimeric IB-ND VLPs are highly immunogenic and could provide complete protection from an IBV or NDV virulent challenge. Chimeric IB-ND VLPs are an appealing vaccine candidate and a promising vaccine platform bearing multivalent antigens.


Assuntos
Antígenos Virais/imunologia , Imunogenicidade da Vacina , Vírus da Bronquite Infecciosa/imunologia , Vírus da Doença de Newcastle/imunologia , Doenças das Aves Domésticas/prevenção & controle , Vacinas de Partículas Semelhantes a Vírus/imunologia , Animais , Anticorpos Antivirais/sangue , Antígenos Virais/genética , Vírus da Bronquite Infecciosa/genética , Vírus da Doença de Newcastle/genética , Organismos Livres de Patógenos Específicos , Vacinação , Proteínas Virais de Fusão/genética , Proteínas Virais de Fusão/imunologia , Vacinas Virais/genética , Vacinas Virais/imunologia
18.
Poult Sci ; 98(7): 2772-2780, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30768138

RESUMO

Avian leukosis virus subgroup J has been found to infect many types of chickens with various genetic backgrounds. The ALV-J strain NX0101, which was isolated from broiler breeders in 2001, mainly induces the formation of myeloid cell tumors. However, strain HN10PY01, which was recently isolated from laying hens, mainly induces the formation of myeloid cell tumors and hemangioma. In order to determine the difference in pathogenicity of the 2 strains in broiler chickens, 2 groups of chicken embryos were infected with NA0101 and HN10PY01 separately. A comparison was made of the mortality, oncogenicity, body weights, indexes for immune organs, levels of ALV group-specific antigen p27, and mRNA expression levels of the tumor-related gene, p53, in ALV-J-infected birds and immune organs of theses chickens in response to Newcastle Disease Virus (NDV) and avian influenza virus subtype H9 (AIV-H9) vaccination. The results indicated that strain NX0101 was highly pathogenic in broiler chickens and led to a 30% mortality rate and 45% oncogenicity, compared with the HN10PY01-infected birds. Weight of chickens was also significantly lower after 15 wk (P < 0.05). In addition, the mRNA expression levels of tumor-related p53 in medulla, liver, and lung in broilers infected with strain NX0101 were significantly higher than those infected with strain HN10PY01 (P < 0.05). These results indicated that strain NX0101 had a higher replication ability in broiler chickens. The findings of this study will contribute to further elucidating the mechanisms underlying host susceptibility and tumor classification in ALV-J-infected chickens.


Assuntos
Vírus da Leucose Aviária/patogenicidade , Neoplasias/virologia , Doenças das Aves Domésticas/virologia , Virulência , Animais , Leucose Aviária/mortalidade , Leucose Aviária/patologia , Peso Corporal , Embrião de Galinha , Galinhas , Vírus da Influenza A/imunologia , Vírus da Doença de Newcastle/imunologia , Vacinas/administração & dosagem
19.
Vet Res ; 50(1): 12, 2019 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-30744668

RESUMO

Infectious bronchitis virus (IBV) causes a major disease problem for the poultry industry worldwide. The currently used live-attenuated vaccines have the tendency to mutate and/or recombine with circulating field strains resulting in the emergence of vaccine-derived variant viruses. In order to circumvent these issues, and to develop a vaccine that is more relevant to Egypt and its neighboring countries, a recombinant avirulent Newcastle disease virus (rNDV) strain LaSota was constructed to express the codon-optimized S glycoprotein of the Egyptian IBV variant strain IBV/Ck/EG/CU/4/2014 belonging to GI-23 lineage, that is prevalent in Egypt and in the Middle East. A wild type and two modified versions of the IBV S protein were expressed individually by rNDV. A high level of S protein expression was detected in vitro by Western blot and immunofluorescence analyses. All rNDV-vectored IBV vaccine candidates were genetically stable, slightly attenuated and showed growth patterns comparable to that of parental rLaSota virus. Single-dose vaccination of 1-day-old SPF White Leghorn chicks with the rNDVs expressing IBV S protein provided significant protection against clinical disease after IBV challenge but did not show reduction in tracheal viral shedding. Single-dose vaccination also provided complete protection against virulent NDV challenge. However, prime-boost vaccination using rNDV expressing the wild type IBV S protein provided better protection, after IBV challenge, against clinical signs and significantly reduced tracheal viral shedding. These results indicate that the NDV-vectored IBV vaccines are promising bivalent vaccine candidates to control both infectious bronchitis and Newcastle disease in Egypt.


Assuntos
Galinhas , Infecções por Coronavirus/veterinária , Vírus da Bronquite Infecciosa/imunologia , Vírus da Doença de Newcastle/imunologia , Doenças das Aves Domésticas/prevenção & controle , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Virais/imunologia , Animais , Linhagem Celular , Infecções por Coronavirus/prevenção & controle , Egito , Vetores Genéticos/imunologia , Vírus da Bronquite Infecciosa/genética , Vírus da Doença de Newcastle/genética , Glicoproteína da Espícula de Coronavírus/genética , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Vacinas Sintéticas/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/genética
20.
Trop Anim Health Prod ; 51(6): 1357-1365, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30706330

RESUMO

The first objective of the present study was to evaluate if the antibodies induced by the live LaSota and killed Newcastle disease (sub-genotype VIIi) vaccines protect the chickens against exposure with pathogenic avian avulavirus-1 (AAvV-1) of chicken and/or pigeon origins. The second objective was to study the effect of vaccines on stressed birds (dexamethasone, aflatoxin, and heat stressed) with respect to antibody production and protection against pathogenic AAvV-1 challenge. Sixty-one-day-old Hubbard chickens were divided into six groups (gA-gF) with ten animals each. All the groups received LaSota (105 EID50, 0.1 ml per chick) on days 7 and 27 via eye drop and one intramuscular injection of a killed vaccine (sub-genotype VIIi) (107.5 EID50, 1 ml) on day 18, except the control birds received the PBS only. Moreover, group gC-DEX received dexamethasone intramuscularly at a dose rate of 1-mg/kg body weight daily; gD-AFLA had received aflatoxin as oral gavage at a dose rate of 30 ppb daily, and gE-HEAT was kept under heat stressed (38 °C) till challenged. All the groups were challenged with AAvV-1 strain of chicken origin of sub-genotype VIIi, except the group gA-pigeon was challenged with pigeon-origin strain (sub-genotype VIm). The result showed that the gA-pigeon and gB-chicken vaccinate showed 100% and 80% protection. The immunosuppressive birds produced low pre-challenge HI titer, and protection was observed at 40%, 50%, and 70% in gC-DEX, gD-AFLA, and gE-HEAT, respectively. Our findings suggest the stress factors such as aflatoxin in the feed and dexamethasone are immunosuppressive in nature and suppress the immune response and its associated protective role during infection.


Assuntos
Doença de Newcastle/prevenção & controle , Vírus da Doença de Newcastle/imunologia , Animais , Anticorpos Antivirais/genética , Galinhas/imunologia , Genótipo , Vacinas de Produtos Inativados , Vacinas Virais/imunologia
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