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1.
Biologicals ; 61: 68-75, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31358411

RESUMO

Severe fever with thrombocytopenia syndrome (SFTS) is an acute infectious disease caused by severe fever with thrombocytopenia syndrome virus (SFTSV). SFTS is mainly characterized by severe fever with thrombocytopenia and has a high mortality rate. The virus has been found in China, South Korea, and Japan. Effective antiviral drugs or vaccines still have been unavailable. Now, two vaccine manufacturers in China are actively engaged in the development of the vaccine. To promote the development of SFTS vaccines and ensure their effective quality control, we developed national antigen and antibody references. We collaborative calibrated the standards; evaluated the homogeneity and stability of the national SFTS standards. The national SFTS vaccine antigen and antibody references met the Chinese national standards and can be used to standardize quality control for the manufacture of SFTS vaccines. And also can be used into the study the dose-response relationship of SFTS vaccines, determine clinical doses, and evaluate vaccine immunogenicity.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Infecções por Bunyaviridae/imunologia , Phlebovirus/imunologia , Vacinas Virais , Animais , Infecções por Bunyaviridae/prevenção & controle , China , Humanos , Padrões de Referência , Células Vero , Vacinas Virais/imunologia , Vacinas Virais/normas
2.
Comp Immunol Microbiol Infect Dis ; 65: 128-131, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31300101

RESUMO

Sheep pox is a disease of veterinary concern to small ruminant producers and veterinary diagnosticians, because of the associated tangible economic losses. The epidemiological analysis of sheep pox, among vaccinated sheep flock in Algeria from 2007 to 2016, showed that the disease outbreaks occurred every year and across all Algeria region with an average of 44.9 outbreaks per year, these outbreaks correlate with the region climate, the flocks' density and the transhumance practices. The one-year post vaccination antibody kinetics evaluation study of the commercially used vaccine in Algeria demonstrated a mild humoral response, the neutralization index range between 0.73 and 1.22. Therefore, the present study recommends a challenge study, using a virulent local strain, to evaluate the vaccine efficacy. Furthermore, quality control approach for the vaccine production processes is required.


Assuntos
Anticorpos Antivirais/sangue , Surtos de Doenças , Infecções por Poxviridae/veterinária , Doenças dos Ovinos/epidemiologia , Potência de Vacina , Vacinas Virais/imunologia , Argélia/epidemiologia , Animais , Cinética , Testes de Neutralização , Infecções por Poxviridae/epidemiologia , Estudos Retrospectivos , Ovinos , Doenças dos Ovinos/virologia , Vacinação , Vacinas Atenuadas/imunologia , Vacinas Virais/normas
3.
Hum Vaccin Immunother ; 15(10): 2249-2257, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31215838

RESUMO

Infection caused by the severe fever and thrombocytopenia syndrome virus (SFTSV) causes a hemorrhagic illness with a mortality between 20% and 40%. Initially recognized in 2009 in China, cases have additionally been documented in Japan and Korea although retrospective studies have documented seroprevalence since 1996. Although case rates have increased due to increased awareness and more widely available diagnostics, SFTSV infection remains rare with the highest rates documented in Korea for Jeju Province (3.5 cases per 100,000 population) and the Inje-gun region (66.2 cases per 100,000). Because of the very low incidence of infection, a placebo-controlled study with 1:1 randomization to evaluate an SFTSV vaccine would require a sample size that is 25% greater than the region of study. We discuss alternatives to licensure. Vaccine effectiveness may be assessed through a registry, comparing rates of infection over time between vaccine recipients versus regional populations. Modeled data can be updated based on actual case rates and population changes over the years of follow-up. Using one model, statistically significant differences are seen after 10 years in Inje-gun and 15 years of follow-up in Jeju. This approach may be applicable to other uncommon infectious diseases for which a standard study design is difficult.


Assuntos
Infecções por Bunyaviridae/epidemiologia , Febres Hemorrágicas Virais/epidemiologia , Doenças Raras/virologia , Vacinas Virais/uso terapêutico , Animais , Bunyaviridae/patogenicidade , Infecções por Bunyaviridae/prevenção & controle , Ensaios Clínicos como Assunto , Modelos Animais de Doenças , Febres Hemorrágicas Virais/prevenção & controle , Humanos , Doenças Raras/prevenção & controle , República da Coreia/epidemiologia , Estudos Retrospectivos , Estudos Soroepidemiológicos , Trombocitopenia/prevenção & controle , Trombocitopenia/virologia , Vacinas Virais/normas
4.
Avian Pathol ; 48(4): 343-351, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30958706

RESUMO

The recombinant Muscovy duck parvovirus (rMDPV) has been recently characterized and identified in China. However, whether other additional rMDPV field isolates exist, and whether these strains possess common molecular characteristics, remain to be explored. In this retrospective study, two new rMDPV isolates, namely, JH06 and JH10, were identified through genome sequencing and recombination analysis. JH06, JH10, and four previously characterized rMDPV strains (SAAS-SHNH, ZW, FJM3, and PT97) underwent the same recombination events in a 1.1-kb region in their VP3 genes and displayed highly consistent beginning and ending breakpoints. JH06, JH10, SAAS-SHNH, ZW, and FJM3, but not PT97, underwent recombination in their P9 promoter regions. In both recombination events, the classical MDPV strain YY acted as the major parent, whereas the virulent strain DY16 and the vaccine strain SYG61v of goose parvovirus (GPV) served as the minor parents. The sequence alignments of inverted terminal repeats (ITRs) revealed that rMDPV strains shared higher identities (96.0%-97.2%) with classical MDPV strains than with GPV and contained typical one-nucleotide-pair deletions in the palindromic stems of their ITRs. This work elucidated the common molecular characteristics and differences of six rMDPV strains. The results of this work will facilitate the preparation of an efficacious vaccine for the protection of Muscovy ducks against rMDPV infection.


Assuntos
Dependovirus/genética , Patos , Infecções por Parvoviridae/veterinária , Doenças das Aves Domésticas/virologia , Sequência de Aminoácidos , Animais , Sequência de Bases , China/epidemiologia , Dependovirus/isolamento & purificação , Dependovirus/patogenicidade , Dados de Sequência Molecular , Infecções por Parvoviridae/epidemiologia , Infecções por Parvoviridae/virologia , Parvovirus/genética , Parvovirus/isolamento & purificação , Parvovirus/patogenicidade , Filogenia , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/prevenção & controle , Distribuição Aleatória , Recombinação Genética , Estudos Retrospectivos , Alinhamento de Sequência/veterinária , Vacinas Virais/normas
5.
Acta Virol ; 63(1): 19-25, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30879309

RESUMO

Chicken infectious anemia (CIA) is an immunosuppressive disease that causes great economic loss in poultry industry globally. This disease is caused by chicken anemia virus (CAV), an icosahedral and single-stranded DNA virus that is transmitted both vertically and horizontally. CAV, which belongs to the genus Gyrovirus has been reported in human, mouse and dog feces. Rapid identification of different strains of gyrovirus with high similarity to CAV has heightened public concern on this virus. Clinical symptoms of this disease such as intramuscular hemorrhage, weight loss, anemia and bone marrow aplasia are prominent in young chickens, while adult chickens experience subclinical symptoms. Biosecurity measures such as good management practice and vaccination have been the most reliable control strategy against this virus. Therefore, this study reviews the current state of CAV under the following subheadings (i) Chicken anemia virus (ii) Pathogenesis of CAV (iii) Serological evaluation of host antibodies to CAV (iv) Association of Marek's disease and infectious bursa disease with CAV infection (v) Genetic diversity and phylogenetics of CAV strains (vi) Current and future vaccine strategy in the control of CAV. In conclusion, improvement on DNA and recombinant vaccines strategy could curtail the economic impact of CAV on poultry birds. Keywords: adjuvant; CAV; chicken; disease.


Assuntos
Vírus da Anemia da Galinha , Infecções por Circoviridae , Doenças das Aves Domésticas , Animais , Anticorpos Antivirais/sangue , Vírus da Anemia da Galinha/classificação , Vírus da Anemia da Galinha/imunologia , Galinhas , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/veterinária , Infecções por Circoviridae/virologia , Aves Domésticas , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/virologia , Vacinação/tendências , Vacinação/veterinária , Vacinas Virais/normas
7.
BMC Vet Res ; 14(1): 371, 2018 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-30486820

RESUMO

BACKGROUND: Foot-and-mouth disease (FMD) can be controlled by either stamping out or vaccination, a choice which depends on both the economic importance of the livestock sector as well as the disease status. In FMD-free countries with vaccination, such as Korea, vaccination programs should guarantee prevention against transmission of FMD. Monitoring of vaccination programs is also essential for ensuring sufficient coverage that will limit the transmission of FMDV. There are several methods to screen FMD virus (FMDV) structural protein (SP) antibodies including SPCE (Solid-phase competitive ELISA), LPBE (Liquid-phase blocking ELISA), and VNT (Virus neutralization test). Among these, SPCE is widely used for serological monitoring since VNT-the gold standard method-has certain practical limitations, such as high costs in terms of time and labor. However, whether SPCE can ensure the vaccination status of individual animals and whole farms is unclear. In this study, SPCE, LPBE and VNT were compared with respect to correlation with each other and sensitivity at commercial pig farms. RESULTS: The positive results obtained by PrioCHECK SPCE differed from those obtained by LPBE and VNT. The sensitivity of SPCE relative to those of the other tests was fairly low. The raw data of SPCE were most highly correlated with those of VNT with XJ strain, while their positivity and negativity were most highly correlated with LPBE. The results of ROC analysis proposed new cut-off for PrioCHECK SPCE higher than the previous 50% inhibition. CONCLUSIONS: The high false positive rate of PrioCHECK SPCE suggested that high seropositivity by SPCE may not guarantee a true vaccination coverage. Adjusting the cut-off percentage (%) inhibition value for SPCE is needed to address this problem, and it is highly recommended that routine FMDV serological monitoring programs using PrioCHECK SPCE should be combined with alternative methods such as LPBE or VNT.


Assuntos
Anticorpos Antivirais/sangue , Febre Aftosa/prevenção & controle , Monitorização Imunológica/métodos , Testes Sorológicos/veterinária , Vacinação/veterinária , Animais , Ensaio de Imunoadsorção Enzimática/veterinária , Febre Aftosa/sangue , Vírus da Febre Aftosa/imunologia , Testes de Neutralização/veterinária , República da Coreia , Proteínas Estruturais Virais/imunologia , Vacinas Virais/normas
8.
J Virol Methods ; 260: 82-87, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30009851

RESUMO

Yellow Fever (YF) is an acute viral hemorrhagic disease prevalent mainly in Africa and Americas, with 20-60% fatality rate in severe forms. Currently, antiviral drugs for the infection are not available, reinforcing the importance of vaccination in resident populations and travelers. Manufactured in 7 different countries, the YF vaccine was first created in 1937 and two substrains are used for production, 17DD and 17D-204. The vaccine produced in Bio-Manguinhos/Brazil uses 17DD substrain and more than 160 million doses have been exported to over 74 countries. The World Health Organization (WHO) recommends that new seed- and working-lots should have the viral genome sequenced in order to check vaccine genetic stability. The aim of this study was to develop and standardize a Sanger-based sequencing protocol for the genetic monitoring of the Brazilian 17DD vaccine. We designed 54 oligos to access the complete YF vaccine genome by RT-PCR and sequencing approach. After protocol standardization, we tested 45 vaccine lots and the corresponding secondary and working seed lots. All 45 lots presented 100% nucleotide identity to each other and to the seed lots. We also detected 2 heterogeneous positions at nucleotides 4523 (C/T) and 6673 (C/T) that may indicate a quasispecies diversity of YF 17DD strain. When compared to the Brazilian GenBank sequence YFU17066, the Brazilian 17DD vaccine presented 6 silent mutations. By applying the sequencing methodology to two YF 17D-204 strains, we showed that our method can also be used to sequence different YF vaccine virus. In summary, we have developed a robust method for the genetic monitoring of YF vaccines, which has been successfully applied in Bio-Manguinhos since 2009 and could also be used by other manufacturers for YF17D-based vaccines. There were no genetic variation in the Brazilian tested lots, highlighting the safety, production consistency and, more importantly, the genetic stability of Bio-Manguinhos' YF vaccine in the last 3 decades.


Assuntos
Controle de Qualidade , Vacinas Virais/normas , Sequenciamento Completo do Genoma , Vacina contra Febre Amarela/normas , Febre Amarela/prevenção & controle , Vírus da Febre Amarela/genética , Brasil , Bases de Dados de Ácidos Nucleicos , Genoma Viral , Humanos , Mutação , Vacinas Virais/genética , Organização Mundial da Saúde , Febre Amarela/imunologia , Vacina contra Febre Amarela/genética , Vírus da Febre Amarela/imunologia
9.
J Pediatric Infect Dis Soc ; 7(2): 93-99, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29741721

RESUMO

The Advisory Committee on Immunization Practices (ACIP), a group of medical and public health experts, meets 3 times per year to develop recommendations for vaccine use in the United States. The group has 15 voting members, each of whom is appointed to a 4-year term. ACIP members and Centers for Disease Control and Prevention (CDC) staff discuss the epidemiology of vaccine-preventable diseases and vaccine research, effectiveness, safety data, and clinical trial results. The ACIP met on October 25 and 26, 2017, to discuss herpes zoster vaccine, the child/adolescent and adult vaccination schedules, Japanese encephalitis (JE) epidemiology and vaccines, pneumococcal vaccines, anthrax vaccines and disaster preparedness, hepatitis A outbreaks, influenza surveillance and vaccination coverage, vaccine safety, and considerations for a potential third dose of measles-mumps-rubella (MMR) vaccine to combat ongoing mumps outbreaks. Representatives from the American Academy of Pediatrics (AAP) (Y. A. M. and D. W. K.) and the Pediatric Infectious Diseases Society (S. T. O.) were present as liaisons from their respective organizations to the ACIP.


Assuntos
Vacinação/normas , Vacinas Virais/normas , Adolescente , Adulto , Comitês Consultivos , Criança , Medicina Baseada em Evidências , Humanos , Esquemas de Imunização , Guias de Prática Clínica como Assunto , Estados Unidos , Vacinação/efeitos adversos , Vacinas Virais/efeitos adversos , Vacinas Virais/uso terapêutico
10.
PLoS One ; 13(4): e0195897, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29652929

RESUMO

BACKGROUND: Modified Vaccinia Ankara (MVA) is a live, viral vaccine under advanced development as a non-replicating smallpox vaccine. A randomised, double-blind, placebo-controlled phase III clinical trial was conducted to demonstrate the humoral immunogenic equivalence of three consecutively manufactured MVA production lots, and to confirm the safety and tolerability of MVA focusing on cardiac readouts. METHODS: The trial was conducted at 34 sites in the US. Vaccinia-naïve adults aged 18-40 years were randomly allocated to one of four groups using a 1:1:1:1 randomization scheme. Subjects received either two MVA injections from three consecutive lots (Groups 1-3), or two placebo injections (Group 4), four weeks apart. Everyone except personnel involved in vaccine handling and administration was blinded to treatment. Safety assessment focused on cardiac monitoring throughout the trial. Vaccinia-specific antibody titers were measured using a Plaque Reduction Neutralization Test (PRNT) and an Enzyme-Linked Immunosorbent Assay (ELISA). The primary immunogenicity endpoint was Geometric Mean Titers (GMTs) after two MVA vaccinations measured by PRNT at trial visit 4. This trial is registered with ClinicalTrials.gov, number NCT01144637. RESULTS: Between March 2013 and May 2014, 4005 subjects were enrolled and received at least one injection of MVA (n = 3003) or placebo (n = 1002). The three MVA lots induced equivalent antibody titers two weeks after the second vaccination, with seroconversion rates of 99·8% (PRNT) and 99·7% (ELISA). Overall, 180 (6·0%) subjects receiving MVA and 29 (2·9%) subjects in the placebo group reported at least one unsolicited Adverse Event (AE) that was considered trial-related. Vaccination was well tolerated without significant safety concerns, particularly regarding cardiac assessment. CONCLUSIONS: The neutralizing and total antibody titers induced by each of the three lots were equivalent. No significant safety concerns emerged in this healthy trial population, especially regarding cardiac safety, thus confirming the excellent safety and tolerability profile of MVA. TRIAL REGISTRATION: ClinicalTrials.gov NCT01144637.


Assuntos
Imunogenicidade da Vacina , Vacina Antivariólica/efeitos adversos , Vacina Antivariólica/imunologia , Vacinas Virais/efeitos adversos , Vacinas Virais/imunologia , Adulto , Anticorpos Antivirais/imunologia , Ensaio de Imunoadsorção Enzimática , Feminino , Voluntários Saudáveis , Humanos , Imunização Secundária , Masculino , Soroconversão , Vacina Antivariólica/normas , Estados Unidos , Vacinação , Vacinas Virais/normas , Adulto Jovem
11.
Curr Pharm Biotechnol ; 18(8): 638-647, 2017 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-28914197

RESUMO

BACKGROUND: Vaccine formulations may contain visible and/or subvisible particles, which can vary in both size and morphology. Extrinsic particles, which are particles not part of the product such as foreign contaminants, are generally considered undesirable and should be eliminated or controlled in injectable products. However, biological products, in particular vaccines, may also contain particles that are inherent to the product. Here we focus on the characterization of visible and subvisible particles in a live, replication-deficient viral vaccine candidate against HSV genital herpes in an early developmental stage. METHOD: HSV-2 viral vaccine was characterized using a panel of analytical methods, including Fourier transform infrared spectroscopy (FTIR), sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), Western blot, liquid chromatography-mass spectrometry (LC-MS), light microscopy, transmission electron microscopy (TEM), micro-flow imaging (MFI), dynamic light scattering (DLS), right angle light scattering (RALS), and intrinsic fluorescence. RESULTS: Particles in HSV-2 vaccine typically ranged from hundreds of nanometers to hundreds of micrometers in size and were determined to be inherent to the product. The infectious titer did not correlate with any trend in subvisible particle concentration and size distribution as shown by DLS, MFI, and TEM under stressed conditions. This suggested that particle changes in the submicron range were related to HSV-2 virion structure and had direct impact on biological activity. It was also observed that subvisible and visible particles could induce aggregation in the viral product. The temperature induced aggregation was observed by RALS, intrinsic fluorescence, and DLS. The increase of subvisible particle size with temperature could be fitted to a two-step thermokinetic model. CONCLUSION: Visible and subvisible particles were found to be inherent to the HSV-2 viral vaccine product. The mechanism of protein aggregation was discussed and a two-step thermokinetic aggregation profile was proposed. The approaches reported in this study may be applied to a variety of vaccines and other biological products, as a way to assess the consistency of the manufacturing process and identify key product quality attributes.


Assuntos
Composição de Medicamentos/métodos , Herpesvirus Humano 2/imunologia , Vacinas Virais/análise , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Eletroforese em Gel de Poliacrilamida , Congelamento , Herpesvirus Humano 2/química , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Agregados Proteicos , Estabilidade Proteica , Espectroscopia de Infravermelho com Transformada de Fourier , Vacinas Virais/normas , Vírion/ultraestrutura
13.
Vet Microbiol ; 209: 75-89, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28341332

RESUMO

Porcine reproductive and respiratory syndrome (PRRS) remains one of the most economically significant diseases in the swine industry worldwide. The current vaccines are less satisfactory to confer protections from heterologous infections and long-term persistence, and the need for better vaccines are urgent. The immunological hallmarks in PRRSV-infected pigs include the unusually poor production of type I interferons (IFNs-α/ß) and the aberrant and delayed adaptive immune responses, indicating that PRRSV has the ability to suppress both innate and adaptive immune responses in the host. Type I IFNs are the potent antiviral cytokines and recent studies reveal their pleiotropic functions in the priming of expansion and maturation of adaptive immunity. Thus, IFN antagonism-negative PRRSV is hypothesized to be attenuated and to build effective and broad- spectrum innate and adaptive immune responses in pigs. Such vaccines are promising alternatives to traditional vaccines for PRRSV.


Assuntos
Interações Hospedeiro-Patógeno/imunologia , Imunidade Inata/imunologia , Interferon Tipo I/imunologia , Síndrome Respiratória e Reprodutiva Suína/imunologia , Vacinas Virais/imunologia , Animais , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , Suínos , Vacinas Virais/normas
14.
Biologicals ; 46: 92-98, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28173977

RESUMO

Severe fever with thrombocytopenia syndrome (SFTS) is caused by a phlebovirus of the Bunyaviridae family, which is designated as SFTS virus (SFTSV). To our knowledge, no efficient SFTSV vaccine exists. Here, we report the identification of a standard virus strain for the eight major SFTSV strains circulating in China for use in evaluating the SFTSV vaccine. Rabbits were immunized with the SFTSV strains and the cross-neutralization capacities of SFTSV anti-sera were determined in microculture cytopathic effect (CPE)-inhibition assays. The mean cross-neutralization capacity of the eight SFTSV anti-sera ranged from 62.4 to 142.6%, compared to autologous strains. The HB29 strain demonstrated strong cross-reactivity with heterologous antibodies, and 33 serum samples from SFTS patients efficiently neutralized HB29, suggesting its broad cross-reactivity. In addition, HB29 demonstrated good replication in Vero and MRC-5 cells (8.0 and 6.0 lg 50% cell culture-infectious dose/mL, respectively) and significant CPE, which satisfied the requirements for a standard virus strain. The HB29 isolate was proven identical to the reported HB29 strain by DNA sequencing, and showed high homology in the S segments with other SFTSV strains (94.8-99.7%). Our results suggest that HB29 may be the best candidate standard strain for use in SFTS vaccine development in China.


Assuntos
Infecções por Bunyaviridae/imunologia , Testes de Neutralização/métodos , Phlebovirus/imunologia , Vacinas Virais/imunologia , Sequência de Aminoácidos , Animais , Grupo com Ancestrais do Continente Asiático , Infecções por Bunyaviridae/etnologia , Infecções por Bunyaviridae/virologia , Linhagem Celular , China , Reações Cruzadas/imunologia , Interações Hospedeiro-Patógeno/imunologia , Humanos , Phlebovirus/genética , Phlebovirus/fisiologia , Filogenia , Controle de Qualidade , Coelhos , Padrões de Referência , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos , Células Vero , Proteínas do Envelope Viral/classificação , Proteínas do Envelope Viral/genética , Vacinas Virais/normas
15.
Vet Microbiol ; 209: 66-74, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28228336

RESUMO

PRRS control is hampered by the inadequacies of existing vaccines to combat the extreme diversity of circulating viruses. Since immune clearance of PRRSV infection may not be dependent on the development of neutralising antibodies and the identification of broadly-neutralising antibody epitopes have proven elusive, we hypothesised that conserved T cell antigens represent potential candidates for development of a novel PRRS vaccine. Previously we had identified the M and NSP5 proteins as well-conserved targets of polyfunctional CD8 and CD4 T cells. To assess their vaccine potential, peptides representing M and NSP5 were encapsulated in hydrophobically-modified chitosan particles adjuvanted by incorporation of a synthetic multi-TLR2/TLR7 agonist and coated with a model B cell PRRSV antigen. For comparison, empty particles and adjuvanted particles encapsulating inactivated PRRSV-1 were prepared. Vaccination with the particulate formulations induced antigen-specific antibody responses, which were most pronounced following booster immunisation. M and NSP5-specific CD4, but not CD8, T cell IFN-γ reactivity was measurable following the booster immunisation in a proportion of animals vaccinated with peptide-loaded particles. Upon challenge, CD4 and CD8 T cell reactivity was detected in all groups, with the greatest responses being detected in the peptide vaccinated group but with limited evidence of an enhanced control of viraemia. Analysis of the lungs during the resolution of infection showed significant M/NSP5 specific IFN-γ responses from CD8 rather than CD4 T cells. Vaccine primed CD8 T cell responses may therefore be required for protection and future work should focus on enhancing the cross-presentation of M/NSP5 to CD8 T cells.


Assuntos
Antígenos Virais/imunologia , Síndrome Respiratória e Reprodutiva Suína/imunologia , Linfócitos T/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/sangue , Formação de Anticorpos/imunologia , Quitosana/química , Peptídeos/administração & dosagem , Peptídeos/imunologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , Suínos , Vacinas Virais/química , Vacinas Virais/normas
16.
Vet Microbiol ; 199: 47-53, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28110784

RESUMO

Originally isolated from swine, the proposed influenza D virus has since been shown to be common in cattle. Inoculation of IDV to naïve calves resulted in mild respiratory disease histologically characterized by tracheitis. As several studies have associated the presence of IDV with acute bovine respiratory disease (BRD), we sought to investigate the efficacy of an inactivated IDV vaccine. Vaccinated calves seroconverted with hemagglutination inhibition titers 137-169 following two doses. Non-vaccinated calves challenged with a homologous virus exhibited signs of mild respiratory disease from days four to ten post challenge which was significantly different than negative controls at days five and nine post challenge. Peak viral shedding of approximately 5 TCID50/mL was measured in nasal and tracheal swabs and bronchoalveolar lavage fluids four to six days post challenge. Viral titers were significantly (P<0.05) decreased 1.4 TCID50/mL, 3.6 TCID50/mL and 5.0 TCID50/mL, respectively, in the aforementioned samples collected from vaccinated animals compared to non-vaccinated controls at peak shedding. Viral antigen was detected in the respiratory epithelium of the nasal turbinates and trachea by immunohistochemistry from all unvaccinated calves but in significantly fewer vaccinates. Inflammation characterized by neutrophils was observed in the nasal turbinate and trachea but not appreciably in lungs. Together these results support an etiologic role for IDV in BRD and demonstrate that partial protection is afforded by an inactivated vaccine.


Assuntos
Complexo Respiratório Bovino/imunologia , Doenças dos Bovinos/imunologia , Doenças dos Bovinos/virologia , Infecções por Orthomyxoviridae/veterinária , Thogotovirus/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/sangue , Antígenos Virais/isolamento & purificação , Complexo Respiratório Bovino/patologia , Complexo Respiratório Bovino/prevenção & controle , Complexo Respiratório Bovino/virologia , Bovinos , Doenças dos Bovinos/prevenção & controle , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia , Vacinação , Vacinas de Produtos Inativados/imunologia , Vacinas de Produtos Inativados/normas , Carga Viral , Vacinas Virais/normas , Eliminação de Partículas Virais
17.
Acta Vet Scand ; 59(1): 4, 2017 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-28057035

RESUMO

BACKGROUND: Porcine reproductive and respiratory syndrome virus (PRRSV) causes significant animal and economic losses worldwide. The infection is difficult to control and PRRSV elimination at local level requires coordinated intervention among multiple farms. This case study describes a successful elimination of PRRSV from all 12 herds on the Horne Peninsula, Denmark, using a combination of load, close, homogenise (LCH) using PRRSV type 2 modified-live vaccine, optimised pig flow, and'10 Golden Rules' (10GR) for biosecurity management. To the authors' knowledge, this is the first successful European PRRSV area elimination project documented in detail. The PRRSV type 2 modified-live vaccine was used as part of the LCH method in breeding herds. Complete or partial depopulation was performed in some infected herds. A simplified biosecurity protocol (10GR) based on the McREBEL™ system of pig flow management, was employed in all herds and at all times throughout the study. RESULTS: At study commencement, all herds were infected with PRRSV, and most were actively shedding virus. In just over 18 months, all 12 herds on the Horne Peninsula were confirmed to be PRRSV negative by polymerase chain reaction testing and negative for antibodies against PRRSV by enzyme-linked immunosorbent assay testing. All herds were subsequently obtained 'Specific Pathogen Free' status for PRRSV. CONCLUSIONS: This study provides compelling evidence suggesting that an area elimination plan combining LCH with PRRSV type 2 vaccination, optimised pig flow, and 10GR for biosecurity management can effectively eliminate PRRSV from a geographic area. Additionally this study confirms the value of a previously unpublished, simplified alternative to the McREBEL system for controlling PRRSV.


Assuntos
Erradicação de Doenças/métodos , Síndrome Respiratória e Reprodutiva Suína/prevenção & controle , Vacinas Virais/normas , Animais , Anticorpos Antivirais/sangue , Dinamarca , Ensaio de Imunoadsorção Enzimática , Modelos Teóricos , Reação em Cadeia da Polimerase , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , Organismos Livres de Patógenos Específicos , Suínos , Vacinas Virais/genética , Vacinas Virais/imunologia
18.
BMC Vet Res ; 12(1): 277, 2016 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-27923365

RESUMO

BACKGROUND: Since the end of 2011 an outbreak of pseudorabies affected Chinese pig herds that had been vaccinated with the commercial vaccine made of Bartha K61 strain. It is now clear that the outbreak was caused by an emergent PRV variant. Even though vaccines made of PRV Bartha K61 strain can confer certain cross protection against PRV variants based on experimental data, less than optimal clinical protection and virus shedding reduction were observed, making the control or eradication of this disease difficult. RESULTS: An infectious clone of PRV AH02LA strain was constructed to generate a gE deletion mutant PRV(LA-AB) strain. PRV(LA-AB) strain can reach a titer of 108.43 TCID50 /mL (50% tissue culture infectious dose) on BHK-21 cells. To evaluate the efficiency of the inactivated vaccine made of PRV(LA-AB) strain, thirty 3-week-old PRV-negative piglets were divided randomly into six groups for vaccination and challenge test. All five piglets in the challenge control showed typical clinical symptoms of pseudorabies post challenge. Sneezing and nasal discharge were observed in four and three piglets in groups C(vaccinated with inactivated PRV Bartha K61 strain vaccine) and D(vaccinated with live PRV Bartha K61 strain vaccine) respectively. In contrast, piglets in both groups A(vaccinated with inactivated PRV LA-AB strain vaccine) and B(vaccinated with inactivated PRV LA-AB strain vaccine with adjuvant) presented mild or no clinical symptoms. Moreover, viral titers detected via nasal swabs were approximately 100 times lower in group B than in the challenge control, and the duration of virus shedding (3-4 days) was shorter than in either the challenge control (5-10 days) or groups C and D (5-6 days). CONCLUSIONS: The infectious clone constructed in this study harbors the whole genome of the PRV variant AH02LA strain. The gE deletion mutant PRV(LA-AB)strain generated from PRV AH02LA strain can reach a high titer on BHK-21 cells. An inactivated vaccine of PRV LA-AB provides clinical protection and significantly reduces virus shedding post challenge, especially if accompanied by the adjuvant CVC1302. While Inactivated or live vaccines made of PRV Barth K61 strain can provide only partial protection in this test.


Assuntos
Vacinas contra Pseudorraiva/normas , Pseudorraiva/prevenção & controle , Doenças dos Suínos/prevenção & controle , Vacinas Virais/normas , Eliminação de Partículas Virais/imunologia , Animais , China , Deleção de Genes , Herpesviridae/genética , Herpesviridae/imunologia , Nariz/virologia , Pseudorraiva/patologia , Pseudorraiva/virologia , Vacinas contra Pseudorraiva/imunologia , Distribuição Aleatória , Suínos , Doenças dos Suínos/patologia , Doenças dos Suínos/virologia , Vacinas de Produtos Inativados/imunologia , Vacinas de Produtos Inativados/normas , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/imunologia , Vacinas Virais/imunologia
19.
J Infect Dis ; 214(suppl 5): S488-S496, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27920179

RESUMO

Chikungunya fever, an acute and often chronic arthralgic disease caused by the mosquito-borne chikungunya virus (CHIKV), has reemerged since 2004 to cause millions of cases. Because CHIKV exhibits limited antigenic diversity and is not known to be capable of reinfection, a vaccine could serve to both prevent disease and diminish human amplification during epidemic circulation. Here, we review the many promising vaccine platforms and candidates developed for CHIKV since the 1970s, including several in late preclinical or clinical development. We discuss the advantages and limitations of each, as well as the commercial and regulatory challenges to bringing a vaccine to market.


Assuntos
Febre de Chikungunya/imunologia , Febre de Chikungunya/prevenção & controle , Vírus Chikungunya/imunologia , Vacinas Virais , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Artralgia/prevenção & controle , Artralgia/virologia , Febre de Chikungunya/virologia , Ensaios Clínicos como Assunto , Epidemias/prevenção & controle , Humanos , Vacinas Atenuadas/imunologia , Vacinas Atenuadas/normas , Vacinas Virais/imunologia , Vacinas Virais/normas
20.
Vet Microbiol ; 195: 144-153, 2016 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-27771060

RESUMO

Malignant catarrhal fever (MCF) is a fatal disease of cattle that, in East Africa, follows contact with wildebeest excreting alcelaphine herpesvirus 1 (AlHV-1). Recently an attenuated vaccine (atAlHV-1) was tested under experimental challenge on Friesian-Holstein (FH) cattle and gave a vaccine efficacy (VE) of approximately 90%. However testing under field conditions on an East African breed, the shorthorn zebu cross (SZC), gave a VE of 56% suggesting that FH and SZC cattle may respond differently to the vaccine. To investigate, a challenge trial was carried out using SZC. Additionally three adjuvant combinations were tested: (i) Emulsigen®, (ii) bacterial flagellin (FliC) and (iii) Emulsigen®+bacterial flagellin. We report 100% seroconversion in all immunized cattle. The group inoculated with atAlHV-1+Emulsigen® had significantly higher antibody titres than groups inoculated with FliC, the smallest number of animals that became infected and the fewest fatalities, suggesting this was the most effective combination. A larger study is required to more accurately determine the protective effect of this regime in SZC. There was an apparent inhibition of the antibody response in cattle inoculated with atAlHV-1+FliC, suggesting FliC might induce an immune suppressive mechanism. The VE in SZC (50-60%) was less than that in FH (80-90%). We speculate that this might be due to increased risk of disease in vaccinated SZC (suggesting that the vaccine may be less effective at stimulating an appropriate immune response in this breed) and/or increased survival in unvaccinated SZC (suggesting that these cattle may have a degree of prior immunity against infection with AlHV-1).


Assuntos
Flagelina/farmacologia , Herpesviridae/imunologia , Febre Catarral Maligna/prevenção & controle , Vacinas Virais , Adjuvantes Imunológicos , Animais , Bovinos , DNA Viral/sangue , Feminino , Células HEK293 , Herpesviridae/classificação , Humanos , Esquemas de Imunização , Masculino , Febre Catarral Maligna/virologia , Soroconversão , Receptor 5 Toll-Like , Vacinas Atenuadas , Vacinas Virais/normas
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