摘要:
Chimeric human-bovine respiratory syncytial virus (RSV) are infectious and attenuated in humans and other mammals and useful in vaccine formulations for eliciting an anti-RSV immune response. Also provided are isolated polynucleotide molecules and vectors incorporating a chimeric RSV genome or antigenome which includes a partial or complete human or bovine RSV “background” genome or antigenome combined or integrated with one or more heterologous gene(s) or genome segment(s) of a different RSV strain. Chimeric human-bovine RSV of the invention include a partial or complete “background” RSV genome or antigenome derived from or patterned after a human or bovine RSV strain or subgroup virus combined with one or more heterologous gene(s) or genome segment(s) of a different RSV strain or subgroup virus to form the human-bovine chimeric RSV genome or antigenome.
摘要:
Recombinant respiratory syncytial virus (RSV) are provided in which expression of the second translational open reading frame encoded by the M2 gene (M2ORF2) is reduced or ablated to yield novel RSV vaccine candidates. Expression of M2 ORF2 is reduced or ablated by modifying a recombinant RSV genome or antigenome to incorporate a frame shift mutation, or one or more stop codons in M2 ORF2. Alternatively, M2 ORF2 is deleted in whole or in part to render the M2-2 protein partially or entirely non-functional or to disrupt its expression altogether. M2 ORF2 deletion and knock out mutants possess highly desirable phenotypic characteristics for vaccine development. These changes specify one or more desired phenotypic changes in the resulting virus or subviral particle. Vaccine candidates are generated that show a change in mRNA transcription, genomic or antigenomic RNA replication, viral growth characteristics, viral antigen expression, viral plaque size, and/or a change in cytopathogenicity. In addition, M2-2 knock out or deletion virus exhibits increased levels of synthesis of viral proteins in cell culture, providing an enriched source of viral antigen or protein for purification and use as a noninfectious subunit vaccine.
摘要:
Chimeric respiratory syncytial virus (RSV) and vaccine compositions thereof are produced by introducing one or more heterologous gene(s) or gene segment(s) from one RSV subgroup or strain into a recipient RSV backround of a different subgroup or strain. The resulting chimeric RSV virus or subviral particle is infectious and attenuated, preferably by introduction of selected mutations specifying attenuated phenotypes into a chimeric genome or antigenome to yield, for example, temperature sensitive (ts) and/or cold adapted (ca) vaccine strains. Alternatively, chimeric RSV and vaccine compositions thereof incorporate other mutations specifying desired structural and/or phenotypic characteristics in an infectious chimeric RSV. Such chimeric RSV incorporate desired mutations specified by insertion, deletion, substitution or rearrangement of one or more selected nucleotide sequence(s), gene(s), or gene segment(s) in a chimeric RSV clone. This provides a method for development of novel vaccines against diverse RSV strains by using a common attenuated backbone as a vector to express protective antigens of heterologous strains. The immune system of an individual is stimulated to induce protection against natural RSV infection, preferably in a multivalent manner to achieve protection against multiple RSV strains and/or subgroups.
摘要:
Chimeric human-bovine respiratory syncytial virus (RSV) are infectious and attenuated in humans and other mammals and useful in vaccine formulations for eliciting an anti-RSV immune response. Also provided are isolated polynucleotide molecules and vectors incorporating a chimeric RSV genome or antigenome which includes a partial or complete human or bovine RSV “background” genome or antigenome combined or integrated with one or more heterologous gene(s) or genome segment(s) of a different RSV strain. In preferred aspects of the invention, chimeric RSV incorporate a partial or complete bovine RSV background genome or antigenome combined with one or more heterologous gene(s) or genome segment(s) from a human RSV. A variety of additional mutations and nucleotide modifications are provided within the human-bovine chimeric RSV of the invention to yield desired phenotypic and structural effects.
摘要:
Recombinant respiratory syncytial virus (RSV) having the position of genes shifted within the genome or antigenome of the recombinant virus are infectious and attenuated in humans and other mammals. Gene shifted RSV are constructed by insertion, deletion or rearrangement of genes or genome segments within the recombinant genome or antigenome and are useful in vaccine formulations for eliciting an anti-RSV immune response. Also provided are isolated polynucleotide molecules and vectors incorporating a recombinant RSV genome or antigenome wherein a gene or gene segment is shifted to a more promoter-proximal or promoter-distal position within the genome or antigenome compared to a wild type position of the gene in the RSV gene map. Shifting the position of genes in this manner provides for a selected increase or decrease in expression of the gene, depending on the nature and degree of the positional shift.
摘要:
Recombinant respiratory syncytial virus (RSV) are provided in which expression of the second translational open reading frame encoded by the M2 gene (M2ORF2) is reduced or ablated to yield novel RSV vaccine candidates. Expression of M2 ORF2 is reduced or ablated by modifying a recombinant RSV genome or antigenome to incorporate a frame shift mutation, or one or more stop codons in M2 ORF2. Alternatively, M2 ORF2 is deleted in whole or in part to render the M2-2 protein partially or entirely non-functional or to disrupt its expression altogether. M2 ORF2 deletion and knock out mutants possess highly desirable phenotypic characteristics for vaccine development. These changes specify one or more desired phenotypic changes in the resulting virus or subviral particle. Vaccine candidates are generated that show a change in mRNA transcription, genomic or antigenomic RNA replication, viral growth characteristics, viral antigen expression, viral plaque size, and/or a change in cytopathogenicity. In addition, M2-2 knock out or deletion virus exhibits increased levels of synthesis of viral proteins in cell culture, providing an enriched source of viral antigen or protein for purification and use as a noninfectious subunit vaccine.
摘要:
Recombinant parainfluenza virus (PIV) are provided in which expression of the C, D and/or V translational open reading frame(s) (ORFs) is reduced or ablated to yield novel PIV vaccine candidates. Expression of the C, D and/or V ORF(s) is reduced or ablated by modifying a recombinant PIV genome or antigenome, for example by introduction of a stop codon, by a mutation in an RNA editing site, by a mutation that alters the amino acid specified by an initiation codon, or by a frame shift mutation in the targeted ORF(s). Alternatively, the C, D and/or V ORF(s) is deleted in whole or in part to render the protein(s) encoded thereby partially or entirely non-functional or to disrupt protein expression altogether. C, D and/or V ORF(s) deletion and knock out mutants possess highly desirable phenotypic characteristics for vaccine development. These deletion and knock out mutations changes specify one or more desired phenotypic changes in the resulting virus or subviral particle. Vaccine candidates are generated that show a change in viral growth characteristics, attenuation, plaque size, and/or a change in cytopathogenicity, among other novel phenotypes. A variety of additional mutations and nucleotide modifications are provided within the C, D and/or V ORF(s) deletion or ablation mutant PIV of the invention to yield desired phenotypic and structural effects.
摘要:
Provided herein are novel recombinant respiratory syncytial viruses (RSV) having an attenuated phenotype that contain mutations in the M2-2 open reading frame that interfere with the expression of the M2-2 protein. The M2-2 mutations may be present in combination with mutations at other loci. Using methods described herein, combinations of mutations are provided to achieve desired levels of attenuation. The recombinant RSV strains described here are suitable for use as live-attenuated RSV vaccines. Also provided are polynucleotide sequences of the described viruses, as well as methods for producing and using the viruses.
摘要:
RNA synthesis by the paramyxovirus respiratory syncytial virus (RSV), a ubiquitous human pathogen, was found to be more complex than previously appreciated for the nonsegmented negative-strand RNA viruses. Intracellular RNA replication of a plasmid-encoded “minigenome” analog of viral genomic RNA was directed by coexpression of the nucleocapsid (N) protein, nucleocapsid phosphoprotein (P), and the large polymerase (L) protein. But, under these conditions, it appeared that the greater part of mRNA synthesis terminated prematurely. However, coexpression of the M2 (ORF1) gene resulted in the efficient production of full-length mRNA. Thus, these results demonstrate that expression of the upstream ORF1, which encoded the previously described 22-kDa M2 protein, was associated with transcription elongation. Accordingly, the claimed invention is directed toward infectious recombinant RSV particles which comprise a recombinant genome or antigenome, as well as the RSV proteins N, P, L, and the RNA polymerase elongation factor M2. This system will permit the introduction of defined changes into infectious RSV which will prove useful in a variety of applications, such as the analysis of RSV molecular biology and pathogenesis, the development of attenuated RSV immunogenic compositions for the preparation of RSV-specific immunological reagents, and the expression of foreign antigens.
摘要:
This invention discloses compositions of DNA and proteins that are useful for preparing vaccines against human respiratory syncytial virus �HRSV!. The DNA compositions include structural genes coding for native structural viral proteins and immunogenic fragments of these proteins. Host cells transformed with the above DNA compositions are also disclosed. Vaccines made from the native structural viral proteins or immunogenic fragments are also disclosed as well as methods for protecting humans by inoculation with these vaccines.