RESUMO
Worldwide spreading of H5 and H7 highly pathogenic influenza viruses of the avian origin, which periodically infect and kill humans without prior adaptation, poses a constant threat of the new pandemic. The effectiveness of the pandemic prevention completely depends on the quality of the existing influenza vaccines. Typical methods of the vaccine production from the antigenically relevant strains are problematic in case of high virulent H5 and H7 viruses. Therefore, new approaches to the construction of the vaccine strains and production technologies are required in order to protect the population.
Assuntos
Vírus da Influenza A/imunologia , Vacinas contra Influenza/uso terapêutico , Influenza Humana/imunologia , Influenza Humana/prevenção & controle , Pandemias/prevenção & controle , Animais , Aves , Humanos , Vacinas contra Influenza/imunologiaRESUMO
Cold-adapted influenza virus A/HK/1/68/162/35(H3N2) was developed as unified donor of attenuation and high reproductive capacity forvaccine strains. The reassortant of this donor with surface antigens of highly pathogenic strain Alchicken/Astana/6/05 (H5N1) was tested in guinea pigs as a live or inactivated preparation. Immunization with both formulations induced equal levels of serum virus specific antibodies, while the level of mucosal antibodies was significantly higher in animals immunized with live virus. The challenge with the homologous virus demonstrated complete virus clearance only in this group, thereby indicating a direct correlation of the protection level with the level of mucosal antibodies.
Assuntos
Anticorpos Antivirais/imunologia , Vírus da Influenza A Subtipo H2N2/imunologia , Virus da Influenza A Subtipo H5N1/imunologia , Vacinas contra Influenza/imunologia , Neuraminidase/imunologia , Infecções por Orthomyxoviridae/prevenção & controle , Vírus Reordenados/imunologia , Adaptação Biológica , Animais , Anticorpos Antivirais/sangue , Temperatura Baixa , Cobaias , Imunidade nas Mucosas , Imunização , Vírus da Influenza A Subtipo H2N2/genética , Virus da Influenza A Subtipo H5N1/genética , Vacinas contra Influenza/administração & dosagem , Neuraminidase/genética , Testes de Neutralização , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/virologia , Vírus Reordenados/genética , Mucosa Respiratória/imunologia , Mucosa Respiratória/virologia , Vacinas AtenuadasRESUMO
The paper gives the results of evaluating the efficiency of deINS1 pandemic H5N1 vaccine candidate VN1203delNS1 which was constructed by reverse genetics on the basis of influenza virus strain A/Vietnam/1203/04. The safety, immunogenicity and cross-protection of the vaccine strain against different H5N1 virus clades were demonstrated in mouse and macaque models. The results showed the possibility of designing a new-generation replication-deficient intranasal influenza vaccine, by applying an approach to deleting the NS1 pathogenicity factor, an antagonist of the interferon system.
Assuntos
Virus da Influenza A Subtipo H5N1/genética , Vacinas contra Influenza/uso terapêutico , Influenza Humana/prevenção & controle , Infecções por Orthomyxoviridae/prevenção & controle , Vacinas Atenuadas/uso terapêutico , Proteínas não Estruturais Virais/genética , Administração Intranasal , Animais , Chlorocebus aethiops , Proteção Cruzada/imunologia , Avaliação Pré-Clínica de Medicamentos , Humanos , Virus da Influenza A Subtipo H5N1/imunologia , Vacinas contra Influenza/genética , Vacinas contra Influenza/imunologia , Influenza Humana/genética , Influenza Humana/imunologia , Interferons/metabolismo , Macaca fascicularis , Camundongos , Infecções por Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/imunologia , Genética Reversa/métodos , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia , Células Vero , Proteínas não Estruturais Virais/imunologiaRESUMO
The interference between two influenza A virus strains was investigated in vivo. In mixed infection of chick embryos or mice two results were observed: maximal reproduction of both strains or interference which resulted in a reduction of reproduction activity, antibody production, or virulence of one of the viruses. No interference was observed upon inoculation of two strains apathogenic for the study host combined with an equal concentration of an infectious virus.
Assuntos
Vírus da Influenza A/fisiologia , Interferência Viral , Replicação Viral , Animais , Anticorpos Antivirais/biossíntese , Embrião de Galinha , Vírus da Influenza A/imunologia , Vírus da Influenza A/patogenicidade , Camundongos , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/microbiologia , Recombinação Genética , Virulência , Cultura de VírusRESUMO
The reactogenicity and immunizing activity of vaccine influenza virus A (H1N1) and B strains used as mono- and bi-preparations in children of 3 to 14 years was studied. No increased reactogenicity after the use of bivaccine was observed in the children. Febrile reactions as well as 9 other clinical symptoms which could indicate the reactogenicity of the vaccines were identical for mono- and bivaccine and corresponded to the requirements of the technical documents for the vaccine. The optimal conditions for the evaluation of the immunogenicity of the B component by HI test were developed, and the necessity of using additionally the enzyme immunoassay for this purpose is substantiated. The above method demonstrated that the immunogenicity of the live influenza type A and B vaccine was high in children. No significant inhibition of immunological parameters was observed when the two viruses were combined in the bivaccine.
Assuntos
Vírus da Influenza A/imunologia , Vírus da Influenza B/imunologia , Vacinas contra Influenza/imunologia , Adolescente , Anticorpos Antivirais/sangue , Criança , Pré-Escolar , Cuba , Humanos , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/efeitos adversos , Influenza Humana/prevenção & controle , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/efeitos adversos , Vacinas Sintéticas/imunologiaRESUMO
Using mutants of fowl plague virus (FRV) which have single temperature-sensitive (ts) mutations in some genes, an analysis was carried out on reisolates from children of 3-6 years, vaccinated with a monovaccine from recombinant strains of influenza type A virus. The recombinants were obtained by crossing of current epidemic strains of subtypes A (HINI) and a (H3N2) with the cold-adapted (XA) ts-donor of attenuation A/Leningrad/134/47/57 (H2N2) from which they, as a rule, inherited 5 ts-mutations in genes 1 (PB2), 2 (PB1), 5 (NP), 7 (M), and 8 (NS). All the reisolates were shown to retain the ts-phenotype. However, in the recombination test some reisolates (most frequently those isolated at late periods of vaccination infection) no ts-mutations could be found in 1-3 genes coding for proteins of the polymerase complex, less frequently for NP and NS proteins but not for M proteins.
