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1.
Emerg Microbes Infect ; 9(1): 949-961, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32378471

ABSTRACT

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.


Subject(s)
Betacoronavirus/physiology , Coronaviridae Infections/pathology , Coronaviridae Infections/prevention & control , Coronavirus Infections/pathology , Coronavirus Infections/prevention & control , Disease Models, Animal , Pandemics/prevention & control , Pneumonia, Viral/pathology , Pneumonia, Viral/prevention & control , Research/trends , Animals , Humans , Middle East Respiratory Syndrome Coronavirus/physiology , SARS Virus/physiology
2.
São Paulo; AMHB;APH; mar. 2020. 62 p.
Monography in Portuguese | LILACS, HomeoIndex Homeopathy, MOSAICO - Integrative health | ID: biblio-1087238

ABSTRACT

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)


Subject(s)
Humans , Epidemic Genius , Clinical Protocols , Coronavirus , Coronaviridae Infections/prevention & control , Coronaviridae Infections/therapy , Ethics, Research , SARS Virus , Epidemics , Homeopathy , Brazil/epidemiology
3.
Proc Natl Acad Sci U S A ; 113(11): 3048-53, 2016 Mar 15.
Article in English | MEDLINE | ID: mdl-26976607

ABSTRACT

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.


Subject(s)
Chiroptera/virology , Communicable Diseases, Emerging/virology , Coronaviridae Infections/virology , Coronaviridae/pathogenicity , Animals , Antibodies, Monoclonal/immunology , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Cells, Cultured , Chlorocebus aethiops , Coronaviridae/genetics , Coronaviridae/immunology , Coronaviridae/isolation & purification , Coronaviridae/physiology , Coronaviridae Infections/prevention & control , Coronaviridae Infections/transmission , Coronaviridae Infections/veterinary , Cross Reactions , Encephalitis, Viral/virology , Epithelial Cells/virology , Host Specificity , Humans , Lung/cytology , Mice , Mice, Inbred BALB C , Mice, Transgenic , Models, Molecular , Peptidyl-Dipeptidase A/genetics , Peptidyl-Dipeptidase A/physiology , Point Mutation , Protein Conformation , Receptors, Virus/genetics , Receptors, Virus/physiology , Recombinant Fusion Proteins/metabolism , SARS Virus/immunology , Species Specificity , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/physiology , Vero Cells , Virus Replication , Zoonoses
4.
Genet Mol Res ; 14(2): 6340-9, 2015 Jun 11.
Article in English | MEDLINE | ID: mdl-26125838

ABSTRACT

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.


Subject(s)
Coronaviridae Infections/immunology , Infectious bronchitis virus/immunology , Poultry Diseases/immunology , Vaccines, Attenuated/immunology , Viral Vaccines/immunology , Animals , Chick Embryo/immunology , Chick Embryo/virology , Coronaviridae Infections/prevention & control , Coronaviridae Infections/virology , Infectious bronchitis virus/pathogenicity , Kidney/immunology , Kidney/virology , Poultry Diseases/prevention & control , Poultry Diseases/virology , Primary Cell Culture , Vaccines, Attenuated/therapeutic use , Viral Load/immunology , Viral Vaccines/therapeutic use
7.
EMBO J ; 32(23): 3055-65, 2013 Nov 27.
Article in English | MEDLINE | ID: mdl-24169568

ABSTRACT

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.


Subject(s)
Antiviral Agents/pharmacology , Coronaviridae Infections/prevention & control , Hepatitis C/prevention & control , Interleukins/metabolism , Receptors, Interferon/metabolism , Receptors, Interleukin/metabolism , Amino Acid Sequence , Blotting, Western , Cell Proliferation , Cells, Cultured , Coronaviridae/pathogenicity , Coronaviridae Infections/metabolism , Coronaviridae Infections/virology , Glycosylation , Hepacivirus/pathogenicity , Hepatitis C/metabolism , Hepatitis C/virology , Humans , Immunoenzyme Techniques , Interferon-gamma/metabolism , Interleukins/chemistry , Interleukins/genetics , Molecular Sequence Data , Protein Conformation , Protein Sorting Signals/physiology , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Receptors, Interferon/genetics , Receptors, Interleukin/genetics , Respiratory System/cytology , Respiratory System/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Sequence Homology, Amino Acid , Virus Replication
8.
East Mediterr Health J ; 19 Suppl 1: S61-7, 2013.
Article in English | MEDLINE | ID: mdl-23888797

ABSTRACT

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.


Subject(s)
Coronaviridae Infections/prevention & control , Disease Outbreaks/prevention & control , Infection Control/methods , Public Health/methods , Severe Acute Respiratory Syndrome/prevention & control , Animals , Coronavirus , Humans , Internationality , Middle East
9.
MMWR Morb Mortal Wkly Rep ; 62(23): 480-3, 2013 Jun 14.
Article in English | MEDLINE | ID: mdl-23760190

ABSTRACT

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.


Subject(s)
Coronaviridae Infections/epidemiology , Global Health , Severe Acute Respiratory Syndrome/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Centers for Disease Control and Prevention, U.S. , Child , Child, Preschool , Coinfection , Coronaviridae Infections/prevention & control , Female , Humans , Male , Middle Aged , Practice Guidelines as Topic , Saudi Arabia/epidemiology , Severe Acute Respiratory Syndrome/prevention & control , Travel , United States , Young Adult
10.
J Immunol ; 186(6): 3642-52, 2011 Mar 15.
Article in English | MEDLINE | ID: mdl-21317392

ABSTRACT

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.


Subject(s)
Cytotoxicity, Immunologic , Encephalomyelitis, Acute Disseminated/immunology , Interleukin-10/biosynthesis , Lymphocyte Activation/immunology , T-Lymphocytes, Cytotoxic/immunology , T-Lymphocytes, Cytotoxic/metabolism , Adoptive Transfer , Animals , Cell Line, Tumor , Cells, Cultured , Coronaviridae Infections/immunology , Coronaviridae Infections/metabolism , Coronaviridae Infections/prevention & control , Encephalomyelitis, Acute Disseminated/pathology , Encephalomyelitis, Acute Disseminated/prevention & control , Inflammation Mediators/metabolism , Interleukin-10/deficiency , Interleukin-10/physiology , Mice , Mice, Inbred C57BL , Mice, Knockout , Mice, Transgenic , Murine hepatitis virus/immunology , T-Lymphocytes, Cytotoxic/transplantation
11.
J Virol ; 84(5): 2511-21, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20032190

ABSTRACT

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.


Subject(s)
Algal Proteins , Antiviral Agents , Coronaviridae Infections/drug therapy , Coronaviridae/drug effects , Lectins , Algal Proteins/pharmacology , Algal Proteins/therapeutic use , Amino Acid Sequence , Animals , Antiviral Agents/pharmacology , Antiviral Agents/therapeutic use , Calorimetry , Cell Line , Coronaviridae/genetics , Coronaviridae/immunology , Coronaviridae/pathogenicity , Coronaviridae Infections/immunology , Coronaviridae Infections/mortality , Coronaviridae Infections/prevention & control , Cytokines/immunology , Female , Humans , Lectins/pharmacology , Lectins/therapeutic use , Lung/pathology , Lung/virology , Membrane Glycoproteins/metabolism , Mice , Mice, Inbred BALB C , Models, Molecular , Molecular Sequence Data , Plant Lectins , Protein Binding , Protein Conformation , SARS Virus/drug effects , SARS Virus/metabolism , Spike Glycoprotein, Coronavirus , Viral Envelope Proteins/metabolism , Zoonoses
12.
Vaccine ; 23(17-18): 2294-7, 2005 Mar 18.
Article in English | MEDLINE | ID: mdl-15755614

ABSTRACT

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.


Subject(s)
Coronaviridae/genetics , Coronaviridae/immunology , Tobacco/genetics , Viral Vaccines/genetics , Viral Vaccines/isolation & purification , Agrobacterium tumefaciens/genetics , Animals , Antigens, Viral/genetics , Coronaviridae Infections/prevention & control , Coronaviridae Infections/veterinary , Epitopes/genetics , Gene Expression , Genes, Viral , Neutralization Tests , Nicotine/pharmacology , Plant Growth Regulators/pharmacology , Plants, Genetically Modified , RNA, Messenger/genetics , RNA, Viral/genetics , Sus scrofa , Swine Diseases/prevention & control , Tobacco/drug effects , Tobacco/growth & development , Vaccines, Edible/genetics , Vaccines, Edible/isolation & purification
13.
Avian Pathol ; 33(6): 605-9, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15763730

ABSTRACT

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.


Subject(s)
Chickens/genetics , Coronaviridae Infections/veterinary , Major Histocompatibility Complex/genetics , Poultry Diseases/genetics , Vaccines, Attenuated/adverse effects , Viral Vaccines/adverse effects , Animals , Coronaviridae Infections/mortality , Coronaviridae Infections/pathology , Coronaviridae Infections/prevention & control , Genetic Predisposition to Disease , Infectious bronchitis virus/immunology , Poultry Diseases/mortality , Retrospective Studies , Trachea/pathology
14.
Acta pediatr. esp ; 61(11): 624-628, dic. 2003.
Article in Spanish | IBECS | ID: ibc-28579

ABSTRACT

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)


Subject(s)
Child , Humans , Coronaviridae Infections/prevention & control , Respiratory Tract Infections/prevention & control , Viral Vaccines/pharmacology , Coronaviridae Infections/transmission , Respiratory Tract Infections/transmission , Infection Control , Infant, Premature , Coronavirus/immunology
16.
New Microbiol ; 25(3): 285-90, 2002 Jul.
Article in English | MEDLINE | ID: mdl-12173769

ABSTRACT

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.


Subject(s)
Coronaviridae Infections/veterinary , Coronaviridae/growth & development , Swine Diseases/virology , Animals , Cells, Cultured , Coronaviridae/immunology , Coronaviridae Infections/immunology , Coronaviridae Infections/prevention & control , Coronaviridae Infections/virology , Cytopathogenic Effect, Viral/immunology , Swine , Swine Diseases/immunology , Swine Diseases/prevention & control , Viral Plaque Assay/veterinary , Viral Vaccines/immunology
17.
Avian Dis ; 45(3): 612-9, 2001.
Article in English | MEDLINE | ID: mdl-11569734

ABSTRACT

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.


Subject(s)
Antibodies, Viral/blood , Chickens , Coronaviridae Infections/veterinary , Infectious bronchitis virus/immunology , Poultry Diseases/prevention & control , Viral Vaccines/immunology , Age Factors , Animals , Coronaviridae Infections/epidemiology , Coronaviridae Infections/immunology , Coronaviridae Infections/prevention & control , Follow-Up Studies , Poultry Diseases/epidemiology , Poultry Diseases/immunology , Seroepidemiologic Studies , Vaccination/veterinary
18.
Avian Dis ; 45(2): 340-8, 2001.
Article in English | MEDLINE | ID: mdl-11417813

ABSTRACT

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.


Subject(s)
Coronaviridae Infections/veterinary , Infectious bronchitis virus/immunology , Nucleocapsid Proteins/genetics , Poultry Diseases/prevention & control , Poxviridae Infections/veterinary , Poxviridae/immunology , Amino Acid Sequence , Animals , Antibodies, Viral/biosynthesis , Cells, Cultured , Chick Embryo , Coronaviridae Infections/immunology , Coronaviridae Infections/prevention & control , Enzyme-Linked Immunosorbent Assay/veterinary , Fibroblasts , Fluorescent Antibody Technique, Indirect , Infectious bronchitis virus/genetics , Nucleocapsid Proteins/biosynthesis , Nucleocapsid Proteins/chemistry , Poultry Diseases/immunology , Poxviridae/genetics , Poxviridae Infections/immunology , Poxviridae Infections/prevention & control , Specific Pathogen-Free Organisms , Vaccines, Synthetic/immunology , Viral Vaccines/immunology
19.
J Gen Virol ; 74 ( Pt 7): 1287-94, 1993 Jul.
Article in English | MEDLINE | ID: mdl-8393072

ABSTRACT

The murine coronavirus neurotropic strain JHM (MHV-JHM) nucleocapsid (N) protein induces a strong T-helper cell response in Lewis rats. It has been shown previously that N-specific CD4+ T cells can confer protection against acute disease upon transfer to otherwise lethally infected rats. To define the major antigenic regions that elicit this T cell response, truncated fragments of N protein were expressed from a bacterial expression vector and employed as T cell antigens. Lymphocytes from either MHV-JHM-infected or immunized rats were stimulated in culture with virus antigen, grown and tested for their specificity to the N protein fragments. The carboxy-terminally located C4-N fragment (95 amino acids) induced the most pronounced proliferative response irrespective of whether the lymphocyte culture was derived from immunized or MHV-JHM-infected rats. We established T cell lines specific for the truncated N protein fragments and tested their potential to mediate protection by transfer experiments. Only the T cell line C4-N and the T cell line specific for the full-length N protein were protective. By contrast, all truncated N protein fragments elicited a humoral immune response and contained antigenic sites recognized by antibodies from diseased rats.


Subject(s)
Antigens, Viral/immunology , CD4 Antigens/metabolism , Capsid/immunology , Coronaviridae Infections/immunology , Coronaviridae/immunology , Encephalomyelitis/immunology , T-Lymphocytes/physiology , Vaccines, Synthetic/immunology , Viral Core Proteins/immunology , Animals , Animals, Suckling , Antibodies, Viral/blood , Antibody Formation , Blotting, Western , Coronaviridae/pathogenicity , Coronaviridae Infections/prevention & control , Encephalomyelitis/prevention & control , Enzyme-Linked Immunosorbent Assay , Rats , Rats, Inbred Lew , T-Lymphocytes, Helper-Inducer/physiology , Viral Vaccines/immunology
20.
Vet Rec ; 131(18): 408-11, 1992 Oct 31.
Article in English | MEDLINE | ID: mdl-1334296

ABSTRACT

Four apparently serologically closely related isolates of infectious bronchitis virus were obtained from two flocks of vaccinated broiler breeders, one mile apart, which were experiencing increased mortality and decreases in egg production. The isolates were serologically distinct from isolates previously described and capable of causing characteristic infectious bronchitis-like respiratory infection in young chicks. In one experiment, the H120 vaccine strain of the virus did not protect the trachea against challenge with the new isolates 21 days later.


Subject(s)
Chickens/microbiology , Coronaviridae Infections/veterinary , Infectious bronchitis virus/isolation & purification , Poultry Diseases/microbiology , Animals , Coronaviridae Infections/epidemiology , Coronaviridae Infections/microbiology , Coronaviridae Infections/prevention & control , Disease Outbreaks/veterinary , Female , Infectious bronchitis virus/classification , Poultry Diseases/epidemiology , Poultry Diseases/prevention & control , Vaccination/veterinary , Virulence
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