Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 117
Filtrar
1.
Nat Rev Immunol ; 20(11): 709-713, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33024281

RESUMO

Immunity is a multifaceted phenomenon. For T cell-mediated memory responses to SARS-CoV-2, it is relevant to consider their impact both on COVID-19 disease severity and on viral spread in a population. Here, we reflect on the immunological and epidemiological aspects and implications of pre-existing cross-reactive immune memory to SARS-CoV-2, which largely originates from previous exposure to circulating common cold coronaviruses. We propose four immunological scenarios for the impact of cross-reactive CD4+ memory T cells on COVID-19 severity and viral transmission. For each scenario, we discuss its implications for the dynamics of herd immunity and on projections of the global impact of SARS-CoV-2 on the human population, and assess its plausibility. In sum, we argue that key potential impacts of cross-reactive T cell memory are already incorporated into epidemiological models based on data of transmission dynamics, particularly with regard to their implications for herd immunity. The implications of immunological processes on other aspects of SARS-CoV-2 epidemiology are worthy of future study.


Assuntos
Anticorpos Antivirais/biossíntese , Betacoronavirus/imunologia , Infecções por Coronaviridae/prevenção & controle , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Vacinas Virais/imunologia , Imunidade Adaptativa/efeitos dos fármacos , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/patogenicidade , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/virologia , Coronaviridae/efeitos dos fármacos , Coronaviridae/imunologia , Infecções por Coronaviridae/epidemiologia , Infecções por Coronaviridae/imunologia , Infecções por Coronaviridae/virologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Reações Cruzadas , Humanos , Imunidade Coletiva/efeitos dos fármacos , Memória Imunológica , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Rhinovirus/efeitos dos fármacos , Rhinovirus/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/biossíntese
2.
Clin Immunol ; 220: 108588, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32905851

RESUMO

Though recent reports link SARS-CoV-2 infections with hyper-inflammatory states in children, most children experience no/mild symptoms, and hospitalization and mortality rates are low in the age group. As symptoms are usually mild and seroconversion occurs at low frequencies, it remains unclear whether children significantly contribute to community transmission. Several hypotheses try to explain age-related differences in disease presentation and severity. Possible reasons for milder presentations in children as compared to adults include frequent contact to seasonal coronaviruses, presence of cross-reactive antibodies, and/or co-clearance with other viruses. Increased expression of ACE2 in young people may facilitate virus infection, while limiting inflammation and reducing the risk of severe disease. Further potential factors include recent vaccinations and a more diverse memory T cell repertoire. This manuscript reviews age-related host factors that may protect children from COVID-19 and complications associated, and addresses the confusion around seropositivity and immunity.


Assuntos
Anticorpos Antivirais/sangue , Betacoronavirus/patogenicidade , Infecções por Coronaviridae/prevenção & controle , Coronaviridae/patogenicidade , Infecções por Coronavirus/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Imunidade Adaptativa/efeitos dos fármacos , Adolescente , Doenças Assintomáticas , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/imunologia , Criança , Coronaviridae/efeitos dos fármacos , Coronaviridae/imunologia , Infecções por Coronaviridae/epidemiologia , Infecções por Coronaviridae/imunologia , Infecções por Coronaviridae/virologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Proteção Cruzada , Feminino , Humanos , Evasão da Resposta Imune/genética , Evasão da Resposta Imune/imunologia , Imunidade Inata/efeitos dos fármacos , Masculino , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Pneumonia Viral/virologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/virologia , Reino Unido/epidemiologia , Vacinação , Adulto Jovem
3.
Emerg Microbes Infect ; 9(1): 949-961, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32378471

RESUMO

The emergences of coronaviruses have caused a serious global public health problem because their infection in humans caused the severe acute respiratory disease and deaths. The outbreaks of lethal coronaviruses have taken place for three times within recent two decades (SARS-CoV in 2002, MERS-CoV in 2012 and SARS-CoV-2 in 2019). Much more serious than SARS-CoV in 2002, the current SARS-CoV-2 infection has been spreading to more than 213 countries, areas or territories and causing more than two million cases up to date (17 April 2020). Unfortunately, no vaccine and specific anti-coronavirus drugs are available at present time. Current clinical treatment at hand is inadequate to suppress viral replication and inflammation, and reverse organ failure. Intensive research efforts have focused on increasing our understanding of viral biology of SARS-CoV-2, improving antiviral therapy and vaccination strategies. The animal models are important for both the fundamental research and drug discovery of coronavirus. This review aims to summarize the animal models currently available for SARS-CoV and MERS-CoV, and their potential use for the study of SARS-CoV-2. We will discuss the benefits and caveats of these animal models and present critical findings that might guide the fundamental studies and urgent treatment of SARS-CoV-2-caused diseases.


Assuntos
Betacoronavirus/fisiologia , Infecções por Coronaviridae/patologia , Infecções por Coronaviridae/prevenção & controle , Infecções por Coronavirus/patologia , Infecções por Coronavirus/prevenção & controle , Modelos Animais de Doenças , Pandemias/prevenção & controle , Pneumonia Viral/patologia , Pneumonia Viral/prevenção & controle , Pesquisa/tendências , Animais , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/fisiologia , Vírus da SARS/fisiologia
4.
São Paulo; AMHB;APH; mar. 2020. 62 p.
Monografia em Português | LILACS, HomeoIndex - Homeopatia, MOSAICO - Saúde integrativa | ID: biblio-1087238

RESUMO

Além da reconhecida aplicação nas doenças crônicas, a homeopatia individualizada também pode atuar de forma resolutiva ou complementar nos casos agudos, incluindo as doenças epidêmicas. No entanto, para atingir esse intento, apresenta uma metodologia semiológica e terapêutica específica que deve ser seguida e respeitada, com o risco de não apresentar a eficácia e a segurança desejada. No caso das doenças epidêmicas, que pela virulência dos seus agentes provoca um quadro sintomatológico comum na maioria dos indivíduos suscetíveis, o medicamento homeopático individualizado (medicamento homeopático do gênio epidêmico) deve apresentar semelhança com o conjunto de sinais e sintomas característicos dos pacientes acometidos nos diferentes estágios de cada surto epidêmico. Estudos evidenciam a eficácia e a segurança desta prática profilática e/ou terapêutica em diversas epidemias do passado. Assim sendo, após o levantamento dos possíveis medicamentos homeopáticos individualizados do gênio epidêmico de cada epidemia, sua aplicação profilática e/ou terapêutica em larga escala deve ser sustentada por ensaios clínicos prévios que demonstrem sua eficácia e segurança, em consonância com os aspectos éticos e bioéticos da pesquisa envolvendo seres humanos. Cumprindo essas premissas da boa prática clínica, elaboramos o atual protocolo com o objetivo de investigar, em ensaio clínico randomizado, duplo-cego e placebo-controlado, a eficácia e a segurança de possíveis medicamentos homeopáticos individualizados do gênio epidêmico da COVID-19, em tratamento adjuvante e complementar de pacientes acometidos pela doença. Caso a a eficácia e a segurança se confirme, e tão somente, o(s) medicamento(s) poderão ser utilizado de forma generalizada e coletiva no tratamento e na prevenção da atual epidemia. (AU)


In addition to the recognized application in chronic diseases, individualized homeopathy can also act in a resolutive or complementary way in acute cases, including epidemic diseases. However, to achieve this intent, it presents a specific semiological and therapeutic methodology that must be followed and respected, with the risk of not presenting the desired efficacy and safety. In the case of epidemic diseases, which due to the virulence of their agents causes a common symptomatological picture in most susceptible individuals, the individualized homeopathic medicine (homeopathic medicine of the epidemic genius) should present similarity with the set of characteristic symptoms and signs of the patients affected in the different stages of each epidemic outbreak. Studies show the efficacy and safety of this prophylactic and/or therapeutic practice in several epidemics of the past. Therefore, after the survey of possible homeopathic drugs individualized from the epidemic genius of each epidemic, its prophylactic and/or large-scale therapeutic application should be supported by previous clinical trials that demonstrate its efficacy and safety, in line with the ethical and bioethical aspects of research involving human beings. Fulfilling these premises of good clinical practice, we developed the current protocol with the objective of investigating, in a randomized, double-blind and placebo-controlled clinical trial, the efficacy and safety of possible individualized homeopathic drugs of epidemic genius of COVID-19, in adjuvant and complementary treatment of patients affected by the disease. If efficacy and safety are confirmed, and only in this condition, the medicine may be used in a generalized and collective manner in the treatment and prevention of the current epidemic. (AU)


Assuntos
Humanos , Gênio Epidêmico , Protocolos Clínicos , Coronavirus , Infecções por Coronaviridae/prevenção & controle , Infecções por Coronaviridae/terapia , Ética em Pesquisa , Vírus da SARS , Epidemias , Homeopatia , Brasil/epidemiologia
5.
Proc Natl Acad Sci U S A ; 113(11): 3048-53, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26976607

RESUMO

Outbreaks from zoonotic sources represent a threat to both human disease as well as the global economy. Despite a wealth of metagenomics studies, methods to leverage these datasets to identify future threats are underdeveloped. In this study, we describe an approach that combines existing metagenomics data with reverse genetics to engineer reagents to evaluate emergence and pathogenic potential of circulating zoonotic viruses. Focusing on the severe acute respiratory syndrome (SARS)-like viruses, the results indicate that the WIV1-coronavirus (CoV) cluster has the ability to directly infect and may undergo limited transmission in human populations. However, in vivo attenuation suggests additional adaptation is required for epidemic disease. Importantly, available SARS monoclonal antibodies offered success in limiting viral infection absent from available vaccine approaches. Together, the data highlight the utility of a platform to identify and prioritize prepandemic strains harbored in animal reservoirs and document the threat posed by WIV1-CoV for emergence in human populations.


Assuntos
Quirópteros/virologia , Doenças Transmissíveis Emergentes/virologia , Infecções por Coronaviridae/virologia , Coronaviridae/patogenicidade , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Células Cultivadas , Chlorocebus aethiops , Coronaviridae/genética , Coronaviridae/imunologia , Coronaviridae/isolamento & purificação , Coronaviridae/fisiologia , Infecções por Coronaviridae/prevenção & controle , Infecções por Coronaviridae/transmissão , Infecções por Coronaviridae/veterinária , Reações Cruzadas , Encefalite Viral/virologia , Células Epiteliais/virologia , Especificidade de Hospedeiro , Humanos , Pulmão/citologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Modelos Moleculares , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/fisiologia , Mutação Puntual , Conformação Proteica , Receptores Virais/genética , Receptores Virais/fisiologia , Proteínas Recombinantes de Fusão/metabolismo , Vírus da SARS/imunologia , Especificidade da Espécie , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/fisiologia , Células Vero , Replicação Viral , Zoonoses
6.
Genet Mol Res ; 14(2): 6340-9, 2015 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-26125838

RESUMO

Infectious bronchitis virus (IBV) can multiply effectively in chick embryo kidney (CEK) cells after adapting to the chick embryo. To investigate the dynamic changes in IBV load in the supernatant of primary CEK cells, we developed an SYBR Green I-based real-time polymerase chain reaction assay to quantify nucleic copy numbers of the IBV-Sczy3 strain. The 20, 54, and 87th generations of CEK-adapted IBV-Sczy3 strains were used to infect CEK cells, and then nucleic copy numbers in the samples of supernatant collected at 12, 24, 36, 48, 60, and 72 h were detected. The results showed that the rapid growth period of the virus load of all the 3 generations was approximately 12-36 h post-infection; the peak of the virus load appeared at 36 h post-infection and then decreased gradually in the order of 20th > 54th > 87th for the 3 generations of CEK-adapted strains; the dynamic change curve of the IBV load in the supernatant of primary CEK cells showed a single peak. The results of this study provide a useful reference for CEK-adapted IBV field strains and the production of CEK-attenuated IBV vaccine.


Assuntos
Infecções por Coronaviridae/imunologia , Vírus da Bronquite Infecciosa/imunologia , Doenças das Aves Domésticas/imunologia , Vacinas Atenuadas/imunologia , Vacinas Virais/imunologia , Animais , Embrião de Galinha/imunologia , Embrião de Galinha/virologia , Infecções por Coronaviridae/prevenção & controle , Infecções por Coronaviridae/virologia , Vírus da Bronquite Infecciosa/patogenicidade , Rim/imunologia , Rim/virologia , Doenças das Aves Domésticas/prevenção & controle , Doenças das Aves Domésticas/virologia , Cultura Primária de Células , Vacinas Atenuadas/uso terapêutico , Carga Viral/imunologia , Vacinas Virais/uso terapêutico
9.
EMBO J ; 32(23): 3055-65, 2013 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-24169568

RESUMO

The IFNL4 gene is a recently discovered type III interferon, which in a significant fraction of the human population harbours a frameshift mutation abolishing the IFNλ4 ORF. The expression of IFNλ4 is correlated with both poor spontaneous clearance of hepatitis C virus (HCV) and poor response to treatment with type I interferon. Here, we show that the IFNL4 gene encodes an active type III interferon, named IFNλ4, which signals through the IFNλR1 and IL-10R2 receptor chains. Recombinant IFNλ4 is antiviral against both HCV and coronaviruses at levels comparable to IFNλ3. However, the secretion of IFNλ4 is impaired compared to that of IFNλ3, and this impairment is not due to a weak signal peptide, which was previously believed. We found that IFNλ4 gets N-linked glycosylated and that this glycosylation is required for secretion. Nevertheless, this glycosylation is not required for activity. Together, these findings result in the paradox that IFNλ4 is strongly antiviral but a disadvantage during HCV infection.


Assuntos
Antivirais/farmacologia , Infecções por Coronaviridae/prevenção & controle , Hepatite C/prevenção & controle , Interleucinas/metabolismo , Receptores de Interferon/metabolismo , Receptores de Interleucina/metabolismo , Sequência de Aminoácidos , Western Blotting , Proliferação de Células , Células Cultivadas , Coronaviridae/patogenicidade , Infecções por Coronaviridae/metabolismo , Infecções por Coronaviridae/virologia , Glicosilação , Hepacivirus/patogenicidade , Hepatite C/metabolismo , Hepatite C/virologia , Humanos , Técnicas Imunoenzimáticas , Interferon gama/metabolismo , Interleucinas/química , Interleucinas/genética , Dados de Sequência Molecular , Conformação Proteica , Sinais Direcionadores de Proteínas/fisiologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Interferon/genética , Receptores de Interleucina/genética , Sistema Respiratório/citologia , Sistema Respiratório/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Homologia de Sequência de Aminoácidos , Replicação Viral
10.
East Mediterr Health J ; 19 Suppl 1: S61-7, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23888797

RESUMO

ABSTRACT There have been many laboratory-based investigations since the emergence of the novel coronaviruses in the autumn of 2012, but most of the parameters required for establishing scientifically the control measures that will protect against them have yet to be determined. Equally, the global distribution of the viruses in their animal reservoir has yet to be established. The experience of investigating and controlling another novel coronavirus, SARS, in 2003 shows how national and local investigations can come together as an international coalition and successfully avert epidemics. A menu of studies that need to be undertaken, especially in the countries experiencing transmission, is presented here.


Assuntos
Infecções por Coronaviridae/prevenção & controle , Surtos de Doenças/prevenção & controle , Controle de Infecções/métodos , Saúde Pública/métodos , Síndrome Respiratória Aguda Grave/prevenção & controle , Animais , Coronavirus , Humanos , Internacionalidade , Oriente Médio
11.
MMWR Morb Mortal Wkly Rep ; 62(23): 480-3, 2013 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-23760190

RESUMO

CDC continues to work in consultation with the World Health Organization (WHO) and other partners to better understand the public health risk posed by the Middle East Respiratory Syndrome Coronavirus (MERS-CoV), formerly known as novel coronavirus, which was first reported to cause human infection in September 2012. The continued reporting of new cases indicates that there is an ongoing risk for transmission to humans in the area of the Arabian Peninsula. New reports of cases outside the region raise concerns about importation to other geographic areas. Nosocomial outbreaks with transmission to health-care personnel highlight the importance of infection control procedures. Recent data suggest that mild respiratory illness might be part of the clinical spectrum of MERS-CoV infection, and presentations might not initially include respiratory symptoms. In addition, patients with comorbidities or immunosuppression might be at increased risk for infection, severe disease, or both. Importantly, the incubation period might be longer than previously estimated. Finally, lower respiratory tract specimens (e.g., sputum, bronchoalveolar lavage, bronchial wash, or tracheal aspirate) should be collected in addition to nasopharyngeal sampling for evaluation of patients under investigation. An Emergency Use Authorization (EUA) was recently issued by the Food and Drug Administration (FDA) to allow for expanded availability of diagnostic testing in the United States.


Assuntos
Infecções por Coronaviridae/epidemiologia , Saúde Global , Síndrome Respiratória Aguda Grave/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Centers for Disease Control and Prevention, U.S. , Criança , Pré-Escolar , Coinfecção , Infecções por Coronaviridae/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Arábia Saudita/epidemiologia , Síndrome Respiratória Aguda Grave/prevenção & controle , Viagem , Estados Unidos , Adulto Jovem
12.
J Immunol ; 186(6): 3642-52, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21317392

RESUMO

Acute viral encephalitis requires rapid pathogen elimination without significant bystander tissue damage. In this article, we show that IL-10, a potent anti-inflammatory cytokine, is produced transiently at the peak of infection by CD8 T cells in the brains of coronavirus-infected mice. IL-10(+)CD8 and IL-10(-)CD8 T cells interconvert during acute disease, possibly based on recent Ag exposure. Strikingly, IL-10(+)CD8 T cells were more highly activated and cytolytic than IL-10(-)CD8 T cells, expressing greater levels of proinflammatory cytokines and chemokines, as well as cytotoxic proteins. Even though these cells are highly proinflammatory, IL-10 expressed by these cells was functional. Furthermore, IL-10 produced by CD8 T cells diminished disease severity in mice with coronavirus-induced acute encephalitis, suggesting a self-regulatory mechanism that minimizes immunopathological changes.


Assuntos
Citotoxicidade Imunológica , Encefalomielite Aguda Disseminada/imunologia , Interleucina-10/biossíntese , Ativação Linfocitária/imunologia , Linfócitos T Citotóxicos/imunologia , Linfócitos T Citotóxicos/metabolismo , Transferência Adotiva , Animais , Linhagem Celular Tumoral , Células Cultivadas , Infecções por Coronaviridae/imunologia , Infecções por Coronaviridae/metabolismo , Infecções por Coronaviridae/prevenção & controle , Encefalomielite Aguda Disseminada/patologia , Encefalomielite Aguda Disseminada/prevenção & controle , Mediadores da Inflamação/metabolismo , Interleucina-10/deficiência , Interleucina-10/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Vírus da Hepatite Murina/imunologia , Linfócitos T Citotóxicos/transplante
13.
J Virol ; 84(5): 2511-21, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20032190

RESUMO

Viruses of the family Coronaviridae have recently emerged through zoonotic transmission to become serious human pathogens. The pathogenic agent responsible for severe acute respiratory syndrome (SARS), the SARS coronavirus (SARS-CoV), is a member of this large family of positive-strand RNA viruses that cause a spectrum of disease in humans, other mammals, and birds. Since the publicized outbreaks of SARS in China and Canada in 2002-2003, significant efforts successfully identified the causative agent, host cell receptor(s), and many of the pathogenic mechanisms underlying SARS. With this greater understanding of SARS-CoV biology, many researchers have sought to identify agents for the treatment of SARS. Here we report the utility of the potent antiviral protein griffithsin (GRFT) in the prevention of SARS-CoV infection both in vitro and in vivo. We also show that GRFT specifically binds to the SARS-CoV spike glycoprotein and inhibits viral entry. In addition, we report the activity of GRFT against a variety of additional coronaviruses that infect humans, other mammals, and birds. Finally, we show that GRFT treatment has a positive effect on morbidity and mortality in a lethal infection model using a mouse-adapted SARS-CoV and also specifically inhibits deleterious aspects of the host immunological response to SARS infection in mammals.


Assuntos
Proteínas de Algas , Antivirais , Infecções por Coronaviridae/tratamento farmacológico , Coronaviridae/efeitos dos fármacos , Lectinas , Proteínas de Algas/farmacologia , Proteínas de Algas/uso terapêutico , Sequência de Aminoácidos , Animais , Antivirais/farmacologia , Antivirais/uso terapêutico , Calorimetria , Linhagem Celular , Coronaviridae/genética , Coronaviridae/imunologia , Coronaviridae/patogenicidade , Infecções por Coronaviridae/imunologia , Infecções por Coronaviridae/mortalidade , Infecções por Coronaviridae/prevenção & controle , Citocinas/imunologia , Feminino , Humanos , Lectinas/farmacologia , Lectinas/uso terapêutico , Pulmão/patologia , Pulmão/virologia , Glicoproteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Modelos Moleculares , Dados de Sequência Molecular , Lectinas de Plantas , Ligação Proteica , Conformação Proteica , Vírus da SARS/efeitos dos fármacos , Vírus da SARS/metabolismo , Glicoproteína da Espícula de Coronavírus , Proteínas do Envelope Viral/metabolismo , Zoonoses
14.
Vaccine ; 23(17-18): 2294-7, 2005 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-15755614

RESUMO

Porcine epidemic diarrhea virus (PEDV) causes acute diarrhea and dehydration in pigs, leading to death with a high mortality. In this study, the synthetic neutralizing epitope gene of PEDV, which was optimized based on the coding sequence of tobacco plant genes being modified, was expressed in the no-nicotine tobacco plants. The synthetic gene was cloned into the plant expression vector under the control of CaMV 35S promoter and transformed by an Agrobacterium-mediated transformation. The amount of synthetic epitope protein of PEDV detected in the transgenic tobacco plants was approximately 2.1% of the total soluble plant protein, which was approximately five-fold higher than that expressed with the native gene.


Assuntos
Coronaviridae/genética , Coronaviridae/imunologia , Tabaco/genética , Vacinas Virais/genética , Vacinas Virais/isolamento & purificação , Agrobacterium tumefaciens/genética , Animais , Antígenos Virais/genética , Infecções por Coronaviridae/prevenção & controle , Infecções por Coronaviridae/veterinária , Epitopos/genética , Expressão Gênica , Genes Virais , Testes de Neutralização , Nicotina/farmacologia , Reguladores de Crescimento de Planta/farmacologia , Plantas Geneticamente Modificadas , RNA Mensageiro/genética , RNA Viral/genética , Sus scrofa , Doenças dos Suínos/prevenção & controle , Tabaco/efeitos dos fármacos , Tabaco/crescimento & desenvolvimento , Vacinas de Plantas Comestíveis/genética , Vacinas de Plantas Comestíveis/isolamento & purificação
15.
Avian Pathol ; 33(6): 605-9, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15763730

RESUMO

Infectious bronchitis is a respiratory disease of chickens that is caused by the coronavirus infectious bronchitis virus (IBV). Virtually all broiler and layer breeder flocks are routinely vaccinated against IBV. Two hatches of 1-day-old chicks from four lines were mistakenly vaccinated for infectious bronchitis using a moderately attenuated vaccine designed for chicks of an older age. The vaccination resulted in high mortality, and chicks from three of four lines died with signs typical of infectious bronchitis. The mortality that occurred using this less-attenuated vaccine was significantly influenced by the genetic line, and the MHC (B) haplotype in chickens of three B congenic lines. B congenic chickens possessing the B*15 haplotype were resistant in contrast to chickens possessing the B*13 or B*21 haplotypes. Chicks from two further hatches of the four lines were vaccinated appropriately with a more attenuated IBV vaccine, and only limited chick mortality was seen. These retrospective data from two repeated hatches confirm earlier data indicating chicken genes influence resistance to IBV, and indicate for the first time that genes tightly linked to the B haplotype are relevant in resistance to IBV. Due to extenuating circumstances it was not possible to verify results with chicks from F2 matings. Factors that may enhance definition of the role of the B haplotype in immune response to IBV, and the desirability for further analysis of a B haplotype-linked influence on immunity to IBV are discussed.


Assuntos
Galinhas/genética , Infecções por Coronaviridae/veterinária , Complexo Principal de Histocompatibilidade/genética , Doenças das Aves Domésticas/genética , Vacinas Atenuadas/efeitos adversos , Vacinas Virais/efeitos adversos , Animais , Infecções por Coronaviridae/mortalidade , Infecções por Coronaviridae/patologia , Infecções por Coronaviridae/prevenção & controle , Predisposição Genética para Doença , Vírus da Bronquite Infecciosa/imunologia , Doenças das Aves Domésticas/mortalidade , Estudos Retrospectivos , Traqueia/patologia
16.
Acta pediatr. esp ; 61(11): 624-628, dic. 2003.
Artigo em Es | IBECS | ID: ibc-28579

RESUMO

El síndrome respiratorio agudo grave (SRAG) es una enfermedad de reciente aparición, que ha causado una gran conmoción en el mundo médico y en la sociedad en general. El agente causal es un nuevo Coronavirus, que ha demostrado cumplir los postulados de Koch. Desde nuestro punto de vista, existe una cuestión sin resolver aún en la patogenia del SRAG: ¿cuál es el responsable final del sufrimiento respiratorio: una lesión viral citopática directa en los neumocitos, una lesión mediada por el sistema inmune en respuesta contra este virus, o ambos componentes? Los datos previos procedentes de estudios en autopsias, sueros y sangre de pacientes adultos sugieren un importante componente inmunoinflamatorio. Lo corrobora también el hecho de que en niños pequeños se trata de una enfermedad con un curso mucho más leve que en adultos. Hasta la fecha, no se han registrado muertes en la población pediátrica. Este dato por sí mismo descarta que exista un efecto viral citopático directo importante: los niños serían los pacientes más afectados debido a la inmadurez de su sistema inmune; además, la gravedad es mayor en los pacientes con un sistema inmune adulto capaz de presentar una respuesta inmunoinflamatoria completa. Adicionalmente, esta observación tiene su repercusión en el desarrollo de vacunas para esta enfermedad. Se deberían evitar utilizar antígenos vacunales virales que pudieran llevar a una respuesta inmunoinflamatoria, como la que tendría lugar en el curso de la enfermedad natural. Por último, hay que estar alerta ante niños paucisintomáticos que transmitan la enfermedad a sus contactos adultos, en los cuales la enfermedad es más grave. En conclusión, los niños demuestran de nuevo que no son una reproducción a escala de un adulto, y que presentan peculiaridades que, sin embargo, pueden ayudar a comprender lo que ocurre en las enfermedades de los adultos (AU)


Assuntos
Criança , Humanos , Infecções por Coronaviridae/prevenção & controle , Infecções Respiratórias/prevenção & controle , Vacinas Virais/farmacologia , Infecções por Coronaviridae/transmissão , Infecções Respiratórias/transmissão , Controle de Infecções , Recém-Nascido Prematuro , Coronavirus/imunologia
18.
New Microbiol ; 25(3): 285-90, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12173769

RESUMO

A strain of porcine epidemic diarrhea virus (PEDV), P-5V, utilized as a live virus vaccine in Japan was infected to a swine cell lines, KSEK6 and IB-RS-2 cells. Clear CPE, characterized by cellular destruction, started to appear in the infected cells on 2-3 days post infection (DPI) and affected cells was completely degenerated on 4 DPI. The virus was serially passaged in the cells even without addition of trypsin. Small but clear plaques were formed under an agar overlay medium on the cells. The infective titer in the order of 10(7.00-7.50) TCID50 per ml was obtained at usual incubation temperature.


Assuntos
Infecções por Coronaviridae/veterinária , Coronaviridae/crescimento & desenvolvimento , Doenças dos Suínos/virologia , Animais , Células Cultivadas , Coronaviridae/imunologia , Infecções por Coronaviridae/imunologia , Infecções por Coronaviridae/prevenção & controle , Infecções por Coronaviridae/virologia , Efeito Citopatogênico Viral/imunologia , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/prevenção & controle , Ensaio de Placa Viral/veterinária , Vacinas Virais/imunologia
19.
Avian Dis ; 45(3): 612-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11569734

RESUMO

In this study, a follow-up was made between 1993 and 1997 from broiler breeders at birth down to offspring broilers at processing, through vertically integrated registration of infectious bronchitis virus (IBV) antibody titers and performance data. All measurements were used two by two in a simple correlation study to calculate the degree to which they were linearly correlated. The antibody patterns in the broiler breeders indicated frequent field infections breaking through vaccinal immunity. Significant correlations measured between antibody titers and production parameters within and between the generations strongly suggested negative effects of IBV infections on laying percentage in the breeders and on mortality and daily weight gain in the broilers. Economic losses associated with IBV infections in the broilers occurred predominantly in flocks hatched with low and erratic maternal antibody titers. We concluded that IBV vaccination strategies should aim at high and uniform antibody titers in the broiler breeders.


Assuntos
Anticorpos Antivirais/sangue , Galinhas , Infecções por Coronaviridae/veterinária , Vírus da Bronquite Infecciosa/imunologia , Doenças das Aves Domésticas/prevenção & controle , Vacinas Virais/imunologia , Fatores Etários , Animais , Infecções por Coronaviridae/epidemiologia , Infecções por Coronaviridae/imunologia , Infecções por Coronaviridae/prevenção & controle , Seguimentos , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/imunologia , Estudos Soroepidemiológicos , Vacinação/veterinária
20.
Avian Dis ; 45(2): 340-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11417813

RESUMO

A stable recombinant fowl poxvirus (rFPV) expressing the C-terminal region (119 amino acids) of the nucleocapsid (N) protein of an infectious bronchitis virus (IBV) strain Ch3 was constructed by inserting the coding sequence within the thymidine kinase gene of fowl poxvirus (FPV) by homologous recombination. The N protein was expressed under control of the vaccinia virus promoter P7.5 in chicken embryo fibroblast cell cultures as seen in immunofluorescence assay and in rFPV-inoculated specific-pathogen-free (SPF) chickens by detecting antibodies with enzyme-linked immunosorbent assay (ELISA). A homologous IBV strain (Ch3) and two heterologous IBV strains (Ch5 and H4) were used to inoculate SPF chickens in a challenge to examine the protective efficacy of the rFPV. When the chickens were challenged with IBV Ch3 or Ch5, the control birds had respiratory signs of infections bronchitis, whereas all the vaccinated birds were clinically normal although low levels of the IBV infection were detected by a differential ELISA. In contrast, in the chickens challenged with IBV H4, all control birds and vaccinated birds suffered from the highly lethal IBV H4 infection. Our results suggest that the C-terminal 119 amino acid of the nucleocapsid expressed by FPV is a host-protective antigen and may induce cross-protective immunity against illness among some IBV strains.


Assuntos
Infecções por Coronaviridae/veterinária , Vírus da Bronquite Infecciosa/imunologia , Proteínas do Nucleocapsídeo/genética , Doenças das Aves Domésticas/prevenção & controle , Infecções por Poxviridae/veterinária , Poxviridae/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Antivirais/biossíntese , Células Cultivadas , Embrião de Galinha , Infecções por Coronaviridae/imunologia , Infecções por Coronaviridae/prevenção & controle , Ensaio de Imunoadsorção Enzimática/veterinária , Fibroblastos , Técnica Indireta de Fluorescência para Anticorpo , Vírus da Bronquite Infecciosa/genética , Proteínas do Nucleocapsídeo/biossíntese , Proteínas do Nucleocapsídeo/química , Doenças das Aves Domésticas/imunologia , Poxviridae/genética , Infecções por Poxviridae/imunologia , Infecções por Poxviridae/prevenção & controle , Organismos Livres de Patógenos Específicos , Vacinas Sintéticas/imunologia , Vacinas Virais/imunologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...