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1.
Sci China Life Sci ; 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33655434

RESUMO

African swine fever virus (ASFV) has been circulating in China for more than two years, and it is not clear whether the biological properties of the virus have changed. Here, we report on our surveillance of ASFVs in seven provinces of China, from June to December, 2020. A total of 22 viruses were isolated and characterized as genotype II ASFVs, with mutations, deletions, insertions, or short-fragment replacement occurring in all isolates compared with Pig/HLJ/2018 (HLJ/18), the earliest isolate in China. Eleven isolates had four different types of natural mutations or deletion in the EP402R gene and displayed a non-hemadsorbing (non-HAD) phenotype. Four isolates were tested for virulence in pigs; two were found to be as highly lethal as HLJ/18. However, two non-HAD isolates showed lower virulence but were highly transmissible; infection with 106 TCID50 dose was partially lethal and caused acute or sub-acute disease, whereas 103 TCID50 dose caused non-lethal, sub-acute or chronic disease, and persistent infection. The emergence of lower virulent natural mutants brings greater difficulty to the early diagnosis of ASF and creates new challenges for ASFV control.

3.
Nat Commun ; 11(1): 4081, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32796842

RESUMO

The unprecedented coronavirus disease 2019 (COVID-19) epidemic has created a worldwide public health emergency, and there is an urgent need to develop an effective vaccine to control this severe infectious disease. Here, we find that a single vaccination with a replication-defective human type 5 adenovirus encoding the SARS-CoV-2 spike protein (Ad5-nCoV) protect mice completely against mouse-adapted SARS-CoV-2 infection in the upper and lower respiratory tracts. Additionally, a single vaccination with Ad5-nCoV protects ferrets from wild-type SARS-CoV-2 infection in the upper respiratory tract. This study suggests that the mucosal vaccination may provide a desirable protective efficacy and this delivery mode is worth further investigation in human clinical trials.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/imunologia , Infecções por Coronavirus/imunologia , Modelos Animais de Doenças , Desenho de Fármacos , Feminino , Vetores Genéticos , Células HEK293 , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/genética
5.
Sensors (Basel) ; 20(8)2020 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-32340181

RESUMO

The best water vapor information layer (BWIL), based on Himawari-8 water vapor bands over a typical region of East Asia, is investigated with the U.S. standard atmospheric profile and European Centre for Medium-Range Weather Forecasts Re-Analysis-interim (ERA-interim) dataset. The sensitivity tests reveal that the height of the BWIL is connected heavily to the amount of water vapor in the atmosphere, and to the satellite zenith angle. According to the temporal and spatial distribution analysis of BWIL, there are two basic features of BWIL. First, it lifts from January to July gradually and descends from July to October in the whole region. Second, it is higher over sea than land. These characteristics may stem from the transport of water vapor by monsoon and the concentration of water vapor in different areas. With multiple water vapor absorption IR bands, Himawari-8 can present water vapor information at multiple pressure layers. The water vapor content of ERA-interim in July 2016 is assessed as an example. By comparing the brightness temperatures from satellite observation and simulation under clear sky conditions, the ERA-interim reanalysis dataset may underestimate the amount of water vapor at pressure layers higher than 280 hPa and overestimate the water vapor quantity at pressure layers from 394 to 328 hPa, yet perform well at 320~260 hPa during this month.

6.
Science ; 368(6494): 1016-1020, 2020 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-32269068

RESUMO

Severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) causes the infectious disease COVID-19 (coronavirus disease 2019), which was first reported in Wuhan, China, in December 2019. Despite extensive efforts to control the disease, COVID-19 has now spread to more than 100 countries and caused a global pandemic. SARS-CoV-2 is thought to have originated in bats; however, the intermediate animal sources of the virus are unknown. In this study, we investigated the susceptibility of ferrets and animals in close contact with humans to SARS-CoV-2. We found that SARS-CoV-2 replicates poorly in dogs, pigs, chickens, and ducks, but ferrets and cats are permissive to infection. Additionally, cats are susceptible to airborne transmission. Our study provides insights into the animal models for SARS-CoV-2 and animal management for COVID-19 control.


Assuntos
Animais Domésticos , Betacoronavirus/fisiologia , Infecções por Coronavirus , Modelos Animais de Doenças , Suscetibilidade a Doenças , Furões , Pandemias , Pneumonia Viral , Animais , Anticorpos Antivirais/sangue , Betacoronavirus/imunologia , Betacoronavirus/isolamento & purificação , Gatos , Galinhas , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Cães , Patos , Fezes/virologia , Feminino , Masculino , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , RNA Viral/isolamento & purificação , Sistema Respiratório/virologia , Especificidade da Espécie , Sus scrofa , Ligação Viral , Replicação Viral
7.
Sci China Life Sci ; 63(5): 623-634, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32124180

RESUMO

African swine fever (ASF) is a devastating infectious disease in swine that is severely threatening the global pig industry. An efficacious vaccine is urgently required. Here, we used the Chinese ASFV HLJ/18 as a backbone and generated a series of gene-deleted viruses. The virulence, immunogenicity, safety, and protective efficacy evaluation in specific-pathogen-free pigs, commercial pigs, and pregnant sows indicated that one virus, namely HLJ/18-7GD, which has seven genes deleted, is fully attenuated in pigs, cannot convert to the virulent strain, and provides complete protection of pigs against lethal ASFV challenge. Our study shows that HLJ/-18-7GD is a safe and effective vaccine against ASFV, and as such is expected to play an important role in controlling the spread of ASFV.


Assuntos
Vírus da Febre Suína Africana/genética , Febre Suína Africana/prevenção & controle , Vacinas Atenuadas/genética , Vacinas Virais/genética , Febre Suína Africana/virologia , Vírus da Febre Suína Africana/metabolismo , Animais , Deleção de Genes , Genoma Viral , Humanos , Proteínas Recombinantes/genética , Análise de Sequência de DNA , Suínos , Vacinas Atenuadas/efeitos adversos , Vacinas Atenuadas/imunologia , Proteínas Virais/metabolismo , Vacinas Virais/imunologia , Virulência
8.
Emerg Microbes Infect ; 8(1): 438-447, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30898043

RESUMO

African swine fever (ASF) entered China in August 2018 and rapidly spread across the entire country, severely threatening the Chinese domestic pig population, which accounts for more than 50% of the pig population worldwide. In this study, an ASFV isolate, Pig/Heilongjiang/2018 (Pig/HLJ/18), was isolated in primary porcine alveolar macrophages (PAMs) from a pig sample from an ASF outbreak farm. The isolate was characterized by using the haemadsorption (HAD) test, Western blotting and immunofluorescence, and electronic microscopy. Phylogenetic analysis of the viral p72 gene revealed that Pig/HLJ/18 belongs to Genotype II. Infectious titres of virus propagated in primary PAMs and pig marrow macrophages were as high as 107.2 HAD50/ml. Specific-pathogen-free pigs intramuscularly inoculated with different virus dosages at 103.5-106.5 HAD50 showed acute disease with fever and haemorrhagic signs. The incubation periods were 3-5 days for virus-inoculated pigs and 9 days for contact pigs. All virus-inoculated pigs died between 6-9 days post-inoculation (p.i.), and the contact pigs died between 13-14 days post-contact (p.c.). Viremia started on day 2 p.i. in inoculated pigs and on day 9 p.c. in contact pigs. Viral genomic DNA started to be detected from oral and rectal swab samples on 2-5 days p.i. in virus-inoculated pigs, and 6-10 days p.c. in contact pigs. These results indicate that Pig/HLJ/18 is highly virulent and transmissible in domestic pigs. Our study demonstrates the threat of ASFV and emphasizes the need to control and eradicate ASF in China.


Assuntos
Vírus da Febre Suína Africana/crescimento & desenvolvimento , Vírus da Febre Suína Africana/isolamento & purificação , Febre Suína Africana/patologia , Febre Suína Africana/virologia , Replicação Viral , Vírus da Febre Suína Africana/classificação , Vírus da Febre Suína Africana/genética , Animais , Sangue/virologia , China , Genótipo , Macrófagos Alveolares/virologia , Boca/virologia , Filogenia , Reto/virologia , Análise de Sobrevida , Sus scrofa , Suínos , Fatores de Tempo
9.
Viruses ; 12(1)2019 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-31905947

RESUMO

Rabies virus (RABV) invades the central nervous system and nearly always causes fatal disease in humans. RABV enters cells via clathrin-mediated endocytosis upon receptor binding. The detailed mechanism of this process and how it is regulated are not fully understood. Here, we carried out a high-through-put RNAi analysis and identified AP2-associated kinase 1 (AAK1), a serine/threonine kinase, as an important cellular component in regulating the entry of RABV. AAK1 knock-down greatly inhibits RABV infection of cells, and AAK1-induced phosphorylation of threonine 156 of the µ subunit of adaptor protein 2 (AP2M1) is found to be required for RABV entry. Inhibition of AAK1 kinase activity by sunitinib blocked AP2M1 phosphorylation, significantly inhibiting RABV infection and preventing RABV from entering early endosomes. In vivo studies revealed that sunitinib prolongs the survival of mice challenged with RABV street virus. Our findings indicate that AAK1 is a potential drug target for postexposure prophylaxis against rabies.


Assuntos
Proteínas Serina-Treonina Quinases/genética , Vírus da Raiva/fisiologia , Internalização do Vírus , Animais , Clatrina , Feminino , Células HEK293 , Humanos , Camundongos Endogâmicos C57BL , Fosforilação , Ligação Proteica , Interferência de RNA , Raiva/virologia
10.
PLoS Pathog ; 14(7): e1007189, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-30028877

RESUMO

Rabies virus (RABV) invades the central nervous system and nearly always causes fatal disease in humans. How RABV interacts with host neuron membrane receptors to become internalized and cause rabid symptoms is not yet fully understood. Here, we identified a novel receptor of RABV, which RABV uses to infect neurons. We found that metabotropic glutamate receptor subtype 2 (mGluR2), a member of the G protein-coupled receptor family that is abundant in the central nervous system, directly interacts with RABV glycoprotein to mediate virus entry. RABV infection was drastically decreased after mGluR2 siRNA knock-down in cells. Antibodies to mGluR2 blocked RABV infection in cells in vitro. Moreover, mGluR2 ectodomain soluble protein neutralized the infectivity of RABV cell-adapted strains and a street strain in cells (in vitro) and in mice (in vivo). We further found that RABV and mGluR2 are internalized into cells and transported to early and late endosomes together. These results suggest that mGluR2 is a functional cellular entry receptor for RABV. Our findings may open a door to explore and understand the neuropathogenesis of rabies.


Assuntos
Vírus da Raiva/patogenicidade , Raiva/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Internalização do Vírus , Animais , Linhagem Celular , Humanos , Camundongos , Raiva/fisiopatologia
11.
Antiviral Res ; 150: 30-38, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29246504

RESUMO

Middle East respiratory syndrome coronavirus (MERS-CoV) has been a highly threatening zoonotic pathogen since its outbreak in 2012. Similar to SARS-CoV, MERS-CoV belongs to the coronavirus family and can induce severe respiratory symptoms in humans, with an average case fatality rate of 35% according to the World Health Organization. Spike (S) protein of MERS-CoV is immunogenic and can induce neutralizing antibodies, thus is a potential major target for vaccine development. Here we constructed a chimeric virus based on the vesicular stomatitis virus (VSV) in which the G gene was replaced by MERS-CoV S gene (VSVΔG-MERS). The S protein efficiently incorporated into the viral envelope and mediated cell entry through binding its receptor, human DPP4. Knockdown of clathrin expression by siRNA drastically abrogated the infection of VSVΔG-MERS in Vero cells. Furthermore, in animal studies, the recombinant virus induced neutralizing antibodies and T cell responses in rhesus monkeys after a single intramuscular or intranasal immunization dose. Our findings indicate the potential of the chimeric VSVΔG-MERS as a rapid response vaccine candidate against emerging MERS-CoV disease.


Assuntos
Anticorpos Antivirais/imunologia , Infecções por Coronavirus/prevenção & controle , Coronavírus da Síndrome Respiratória do Oriente Médio/imunologia , Linfócitos T/imunologia , Vacinas Sintéticas/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Chlorocebus aethiops , Dipeptidil Peptidase 4/metabolismo , Modelos Animais de Doenças , Expressão Gênica , Genes Reporter , Vetores Genéticos/genética , Vetores Genéticos/imunologia , Humanos , Imunoglobulina G/imunologia , Macaca mulatta , Masculino , Linfócitos T/metabolismo , Vacinas Sintéticas/genética , Células Vero , Vacinas Virais/genética , Internalização do Vírus
12.
Arch Virol ; 162(2): 359-367, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27757685

RESUMO

Bovine ephemeral fever (BEF) is caused by the arthropod-borne bovine ephemeral fever virus (BEFV), which is a member of the family Rhabdoviridae and the genus Ephemerovirus. BEFV causes an acute febrile infection in cattle and water buffalo. In this study, a recombinant Newcastle disease virus (NDV) expressing the glycoprotein (G) of BEFV (rL-BEFV-G) was constructed, and its biological characteristics in vitro and in vivo, pathogenicity, and immune response in mice and cattle were evaluated. BEFV G enabled NDV to spread from cell to cell. rL-BEFV-G remained nonvirulent in poultry and mice compared with vector LaSota virus. rL-BEFV-G triggered a high titer of neutralizing antibodies against BEFV in mice and cattle. These results suggest that rL-BEFV-G might be a suitable candidate vaccine against BEF.


Assuntos
Anticorpos Neutralizantes/biossíntese , Anticorpos Antivirais/biossíntese , Vírus da Febre Efêmera Bovina/genética , Febre Efêmera/prevenção & controle , Vírus da Doença de Newcastle/genética , Vacinas Virais/genética , Animais , Bovinos , Embrião de Galinha , Cricetinae , Cães , Febre Efêmera/imunologia , Febre Efêmera/virologia , Vírus da Febre Efêmera Bovina/efeitos dos fármacos , Vírus da Febre Efêmera Bovina/imunologia , Células Epiteliais/virologia , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/imunologia , Glicoproteínas/administração & dosagem , Glicoproteínas/genética , Glicoproteínas/imunologia , Imunização , Células Madin Darby de Rim Canino , Camundongos , Camundongos Endogâmicos BALB C , Vírus da Doença de Newcastle/imunologia , Vírus Reordenados/genética , Vírus Reordenados/imunologia , Vacinas Sintéticas , Proteínas Virais/administração & dosagem , Proteínas Virais/genética , Proteínas Virais/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/imunologia
13.
J Integr Agric ; 16(10): 2264-2273, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32288953

RESUMO

Middle East respiratory syndrome coronavirus (MERS-CoV), a member of the Coronaviridae family, is the causative pathogen for MERS that is characterized by high fever, pneumonia, acute respiratory distress syndrome (ARDS), as well as extrapulmonary manifestations. Currently, there are no approved treatment regimens or vaccines for MERS. Here, we generated recombinant nonvirulent Newcastle disease virus (NDV) LaSota strain expressing MERS-CoV S protein (designated as rLa-MERS-S), and evaluated its immunogenicity in mice and Bactrian camels. The results revealed that rLa-MERS-S showed similar growth properties to those of LaSota in embryonated chicken eggs, while animal immunization studies showed that rLa-MERS-S induced MERS-CoV neutralizing antibodies in mice and camels. Our findings suggest that recombinant rLa-MERS-S may be a potential MERS-CoV veterinary vaccine candidate for camels and other animals affected by MERS.

14.
Virol J ; 13: 109, 2016 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-27342050

RESUMO

BACKGROUND: West Nile virus (WNV) is an emerging zoonotic pathogen which is harmful to human and animal health. Effective vaccination in susceptible hosts should protect against WNV infection and significantly reduce viral transmission between animals and from animals to humans. A versatile vaccine suitable for different species that can be delivered via flexible routes remains an essential unmet medical need. In this study, we developed a recombinant avirulent Newcastle disease virus (NDV) LaSota strain expressing WNV premembrane/envelope (PrM/E) proteins (designated rLa-WNV-PrM/E) and evaluated its immunogenicity in mice, horses, chickens, ducks and geese. RESULTS: Mouse immunization experiments disclosed that rLa-WNV-PrM/E induces significant levels of WNV-neutralizing antibodies and E protein-specific CD4+ and CD8+ T-cell responses. Moreover, recombinant rLa-WNV-PrM/E elicited significant levels of WNV-specific IgG in horses upon delivery via intramuscular immunization, and in chickens, ducks and geese via intramuscular, oral or intranasal immunization. CONCLUSIONS: Our results collectively support the utility of rLa-WNV-PrM/E as a promising WNV veterinary vaccine candidate for mammals and poultry.


Assuntos
Mamíferos/imunologia , Vírus da Doença de Newcastle/genética , Doenças das Aves Domésticas/imunologia , Vacinas Virais/imunologia , Febre do Nilo Ocidental/prevenção & controle , Vírus do Nilo Ocidental/imunologia , Animais , Anticorpos Antivirais/imunologia , Galinhas , Feminino , Vetores Genéticos/genética , Vetores Genéticos/imunologia , Humanos , Mamíferos/virologia , Camundongos , Vírus da Doença de Newcastle/metabolismo , Doenças das Aves Domésticas/prevenção & controle , Doenças das Aves Domésticas/virologia , Vacinação , Proteínas do Envelope Viral/administração & dosagem , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/genética , Febre do Nilo Ocidental/imunologia , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/genética
16.
Exp Parasitol ; 153: 39-44, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25746893

RESUMO

For the first time, we show here that perforin-like (TgPLP1) is expressed in bradyzoites of Toxoplasma gondii. An immunofluorescence assay (IFA) and immunohistochemistry (IHC) revealed that TgPLP1 is expressed in T. gondii-encysted and in vitro-induced bradyzoites, TgPLP1 is distributed in micronemes in a manner similar to its distribution in tachyzoites. To shed light on the function of TgPLP1 in bradyzoites, quantitative PCR revealed that the expression level of TgPLP1 gene decreased over time during differentiation into bradyzoites in vitro. This finding suggests that TgPLP1 may play a role in the rupture of tissue cysts or the maintenance of cyst structure, although the exact function of this gene in the bradyzoites is still unknown.


Assuntos
Perforina/metabolismo , Proteínas de Protozoários/metabolismo , Toxoplasma/metabolismo , Toxoplasmose/parasitologia , Animais , Linhagem Celular , Feminino , Humanos , Estágios do Ciclo de Vida , Camundongos Endogâmicos BALB C , Microssomos/parasitologia , Perforina/genética , Transporte Proteico , Proteínas de Protozoários/genética , Coelhos , Toxoplasma/genética , Toxoplasma/crescimento & desenvolvimento
17.
Parasitol Res ; 113(12): 4335-48, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25248513

RESUMO

Avian coccidiosis, caused by Eimeria spp., is one of the major parasitic diseases in birds. Cysteine protease is a major virulence factor in parasitic protozoa, and it may be a suitable chemotherapeutic target and vaccine candidate molecule. A 100 amino acid (aa.) partial sequence of cathepsin L, which is a cysteine protease, was reported by Katrib et al. (Ac. No. CDJ41293) (2012). A 219 aa. sequence was reported by Reid et al. (Ac. No. AFV92863) (2013). However, the open reading frame (ORF) was not reported. In this study, a full sequence of a cathepsin-L-like peptidase in Eimeria tenella (EtcatL) was obtained and its biochemical characterizations and expression profiles were analyzed across different stages of the parasite's life cycle. Results showed that the EtcatL gene encodes a protein 470 aa. in length, with 47 and 49% identity to Toxoplasma gondii and Eimeria acervulina. Considering the close phylogenetic relationship, TgcatL (PDB. ID 3F75) was selected for use as a template for homology modeling with quality factors of 90.9. Gelatin SDS-PAGE showed it to exert protease activity at ≈38 and ≈26 kDa. Further analysis showed the kinetic parameters of the recombinant peptidase to be K m = 8.9 µM and V max = 5.7 RFU/s µM at pH 5.5 containing 10 mM dithiothreitol (DTT) in the reaction matrix, and the IC50 value of E64 was 65.32 ± 3.02 nM. The recombinant protein was active from 25 to 50 °C, with optimal activity at 42 °C. The RT-PCR and Western blot results showed it to be expressed mainly at the endogenous stages and the initial phase of the sporulation. The protective experiment showed that chickens immunized with 100 and 200 µg rEtcatL had reduction of weight loss values 48.7 and 57.9% those of infected controls, respectively. Their reduction of lesion scores (RLS) were 25.0 and 47.2% that of control chickens, and relative oocyst production (ROP) was 39.6 and 15.5% that of control chickens. These results indicate that the EtcatL can be used as an effective immunogen, and further studies are needed to enhance its potential as a vaccine candidate molecule.


Assuntos
Anticorpos Antiprotozoários/imunologia , Catepsina L/genética , Galinhas/imunologia , Coccidiose/veterinária , Eimeria tenella/enzimologia , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Sequência de Bases , Catepsina L/imunologia , Catepsina L/metabolismo , Galinhas/parasitologia , Coccidiose/imunologia , Coccidiose/parasitologia , Coccidiose/prevenção & controle , Eimeria tenella/genética , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Dados de Sequência Molecular , Oocistos , Filogenia , Proteínas Recombinantes
18.
Exp Parasitol ; 133(2): 121-30, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23201216

RESUMO

Although IL-17 is a key factor in Th17 lineage host responses and plays critical roles in immunological control of a variety of infectious diseases, the contribution of IL-17 to immune function during Eimeria tenella infection is unknown. In the present study, we used an experimental E. tenella infection model to clarify the role of Th17-associated response in the resulting immune response by quantitative real-time PCR assays. We observed robust production of STAT-3 (the transcription factors), IL-1ß, IL-6 and IL-17 in cecal intraepithelial lymphocytes during the early infection, peaking at 6h p.i. and declining thereafter. The expression of TGF-ß was moderately upregulated and had 2 peaks at 6 and 72h p.i. during the early infection. To further investigate the role of chIL-17 during the infection, we treated the infected chickens with IL-17 and its neutralized antibody. As a result, the reduced fecal oocyst shedding and cecal lesion scores, but enhanced body weight gains were observed in IL-17 neutralized chickens. The results of histopathology showed that the neutrophils recruitment diminished and the parasite burden in IL-17 neutralized chickens decreased. These results may be due to the significant decrease in the production of IL-17, IL-6 and TGF-ß, but enhanced IL-12 and IFN-γ expression in IL-17 neutralized chickens. The converse results were shown in IL-17 treated infected-chickens in which chickens showed increased fecal oocyst shedding, exacerbated lesion scores, and reduced body weight gains. These results suggested that chicken IL-17 might mediate E. tenella - induced immunopathology during the infection.


Assuntos
Galinhas/parasitologia , Coccidiose/veterinária , Eimeria tenella/imunologia , Interleucina-17/imunologia , Doenças das Aves Domésticas/imunologia , Células Th17/imunologia , Animais , Anticorpos Antiprotozoários/imunologia , Ceco/patologia , Clonagem Molecular , Coccidiose/imunologia , Coccidiose/patologia , Eimeria tenella/patogenicidade , Fezes/parasitologia , Regulação da Expressão Gênica , Interferon gama/metabolismo , Interleucina-12/metabolismo , Interleucina-17/genética , Interleucina-17/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Neutrófilos/imunologia , Reação em Cadeia da Polimerase/veterinária , Doenças das Aves Domésticas/parasitologia , Doenças das Aves Domésticas/patologia , Coelhos , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Organismos Livres de Patógenos Específicos , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/metabolismo , Ganho de Peso
19.
Vet Parasitol ; 188(3-4): 239-46, 2012 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-22494937

RESUMO

Heat shock proteins have been reported to stimulate the immune system via innate receptors. Our study found that the novel immunopotentiator, Eimeria tenella (E. tenella) heat shock protein 70 (HSP70), enhanced protective immunity elicited by E. tenella antigen microneme protein 2 (EtMIC2) against avian coccidiosis. It demonstrated that the expression of TLR2 and TLR4 were strongly upregulated in EtHSP70 and EtMIC2 plus EtHSP70 stimulated chicken embryo fibroblasts (CEF) compared with untreated controls and EtMIC2 alone. In addition, the same treatment induced high levels of interleukin (IL)-12 and interferon (IFN)-γ that are critical cytokines of innate immunity. In vivo experiments involved using broiler chickens subcutaneously immunized with EtMIC2 alone or EtMIC2 plus EtHSP70 at 7 and 14 days post-hatch, which were then orally challenged with live E. tenella at 7 days following secondary immunization. Body weight gains, cecal lesion scores, fecal oocyst shedding, serum antibody responses against MIC2, and intestinal cytokine transcript levels were assessed as measures of protective immunity. Chickens immunized with EtMIC2 plus EtHSP70 showed increased body weight gains, decreased oocyst shedding, increased serum antibody responses, and high levels of IL-12, IFN-γ, and IL-17 compared with the EtMIC2 only or control groups. Moreover, chickens immunized with EtHSP70 alone showed significantly protective effect against E. tenella infection. In summary, this study provides the first evidence of the immunoenhancing activities of EtHSP70 in poultry.


Assuntos
Galinhas/parasitologia , Coccidiose/veterinária , Eimeria tenella/imunologia , Proteínas de Choque Térmico HSP70/imunologia , Doenças das Aves Domésticas/prevenção & controle , Animais , Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/imunologia , Embrião de Galinha , Coccidiose/imunologia , Coccidiose/parasitologia , Coccidiose/prevenção & controle , Citocinas/genética , Fezes/parasitologia , Imunidade Inata , Oocistos , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/parasitologia , Proteínas de Protozoários/imunologia , Vacinas Protozoárias/imunologia , Distribuição Aleatória , Proteínas Recombinantes/imunologia , Transdução de Sinais/genética , Vacinação/veterinária , Ganho de Peso
20.
Exp Parasitol ; 130(4): 442-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22326592

RESUMO

Coccidiosis is an economically important protozoan disease worldwide caused by Eimeria parasites. Toll-like receptors (TLRs), a family of highly conserved proteins, are involved in pathogen detection by initiating host responses, and play important roles in the reduction and clearance of pathogens. Little is known about the roles of chicken TLRs during Eimeria tenella infection. We detected the dynamic changes in the expression of TLRs and associated cytokines in the cecum of E. tenella-infected chickens during the early stage of infection. Day-old (Experiment 1) and three-week-old (Experiment 2) chickens were orally gavaged with 10,000 oocysts (30 chickens each experiment), and their cecum intraepithelial lymphocytes were collected at 3, 6, 12, 24, 48, and 72h post-infection (hpi). Expression profiling of TLR1LA, TLR4, TLR5, TLR7, TLR21, and IFN-α, IFN-ß, IFN-γ, IL-1ß, IL-12 genes were analyzed using quantitative real-time polymerase chain reaction. Almost all TLR transcripts were transiently increased at 3hpi in Experiment 1. In three-week-old chickens, TLR1LA, TLR4, TLR5, TLR7, and TLR21 expression was upregulated at 12hpi, and TLR1LA, TLR5, and TLR21 were highly expressed at 72hpi. In day-old chickens, IFN-α, IFN-ß, IFN-γ, IL-1ß, and IL-12 expression was significantly upregulated at 3hpi (156.1-1117.1-fold change), in comparison to the different peak level times and relatively small changes for these cytokines in the three-week-old chickens. Our results provide a valuable overview for the expression pattern of TLRs and associated cytokines during the early stage of E. tenella infection in chickens.


Assuntos
Galinhas/parasitologia , Coccidiose/veterinária , Citocinas/metabolismo , Eimeria tenella/metabolismo , Doenças das Aves Domésticas/imunologia , Receptores Toll-Like/metabolismo , Animais , Ceco/imunologia , Ceco/parasitologia , Coccidiose/imunologia , Coccidiose/parasitologia , Citocinas/genética , Citocinas/imunologia , DNA Complementar/metabolismo , Eimeria tenella/genética , Eimeria tenella/imunologia , Perfilação da Expressão Gênica , Imunidade Inata , Linfócitos/imunologia , Doenças das Aves Domésticas/parasitologia , RNA de Protozoário/análise , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Organismos Livres de Patógenos Específicos , Receptores Toll-Like/genética , Receptores Toll-Like/imunologia
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