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Nature Microbiology Sep 2023Timely detection of outbreaks is needed for poliovirus eradication, but gold standard detection in the Democratic Republic of the Congo takes 30 days (median). Direct...
Timely detection of outbreaks is needed for poliovirus eradication, but gold standard detection in the Democratic Republic of the Congo takes 30 days (median). Direct molecular detection and nanopore sequencing (DDNS) of poliovirus in stool samples is a promising fast method. Here we report prospective testing of stool samples from suspected polio cases, and their contacts, in the Democratic Republic of the Congo between 10 August 2021 and 4 February 2022. DDNS detected polioviruses in 62/2,339 (2.7%) of samples, while gold standard combination of cell culture, quantitative PCR and Sanger sequencing detected polioviruses in 51/2,339 (2.2%) of the same samples. DDNS provided case confirmation in 7 days (median) in routine surveillance conditions. DDNS enabled confirmation of three serotype 2 circulating vaccine-derived poliovirus outbreaks 23 days (mean) earlier (range 6-30 days) than the gold standard method. The mean sequence similarity between sequences obtained by the two methods was 99.98%. Our data confirm the feasibility of implementing DDNS in a national poliovirus laboratory.
Topics: Poliovirus; Nanopore Sequencing; Polymerase Chain Reaction; Dansyl Compounds
PubMed: 37591995
DOI: 10.1038/s41564-023-01453-4 -
Biologicals : Journal of the... Dec 1993The live attenuated Sabin strains of poliovirus have proven their efficacy at inducing a good humoral and secretory antibody response in humans. The extensive... (Review)
Review
The live attenuated Sabin strains of poliovirus have proven their efficacy at inducing a good humoral and secretory antibody response in humans. The extensive characterization of poliovirus neutralization antigenic sites and the atomic resolution of the three-dimensional structure of the viral capsid have enabled the use of the most stably attenuated poliovirus strain (the Sabin type 1 strain) as a vector for the presentation of short foreign antigenic domains in place of one of its own neutralization antigenic sites. The creation of such chimeras has been achieved by manipulating poliovirus infectious cDNA and transfecting the resulting chimeric cDNAs onto susceptible cell cultures. However, this epitope-presentation system has a limitation in terms of the sequence and size of the foreign domain that can be incorporated into the poliovirus capsid without disrupting virus viability. This has led to the construction of poliovirus hybrid genomes bearing insertions of longer heterologous sequences in place of part of the poliovirus structural genes. Upon transfection onto susceptible cells providing the poliovirus structural proteins in trans (e.g. cells previously infected with the Sabin 1 strain), stocks of encapsidated RNA replicons which expressed the foreign protein could be obtained. In addition, viable recombinant viruses bearing insertions of heterologous sequences at various places into the poliovirus genome without deleting poliovirus sequences have been reported. Potential applications of these chimeric and recombinant polioviruses in the engineering of new recombinant vaccines are discussed.
Topics: Animals; Antigens, Viral; Capsid; Central Nervous System; Cloning, Molecular; Defective Viruses; Encephalomyocarditis virus; Genetic Vectors; Genome, Viral; Guinea Pigs; Haplorhini; Immunization; Mice; Organ Specificity; Poliovirus; Rabbits; Recombination, Genetic; Viral Vaccines; Virulence
PubMed: 8024753
DOI: 10.1006/biol.1993.1098 -
Annual Review of Microbiology 2002Structural studies of polio- and closely related viruses have provided a series of snapshots along their cell entry pathways. Based on the structures and related... (Review)
Review
Structural studies of polio- and closely related viruses have provided a series of snapshots along their cell entry pathways. Based on the structures and related kinetic, biochemical, and genetic studies, we have proposed a model for the cell entry pathway for polio- and closely related viruses. In this model a maturation cleavage of a capsid protein precursor locks the virus in a metastable state, and the receptor acts like a transition-state catalyst to overcome an energy barrier and release the mature virion from the metastable state. This initiates a series of conformational changes that allow the virus to attach to membranes, form a pore, and finally release its RNA genome into the cytoplasm. This model has striking parallels with emerging models for the maturation and cell entry of more complex enveloped viruses such as influenza virus and HIV.
Topics: Capsid; Humans; Membrane Proteins; Models, Genetic; Models, Molecular; Poliovirus; Receptors, Virus; Virion; Virus Integration
PubMed: 12142481
DOI: 10.1146/annurev.micro.56.012302.160757 -
Philosophical Transactions of the Royal... Jun 1989We have solved the structure of the Mahoney strain of type 1 and the Sabin (attenuated vaccine) strain of type 3 poliovirus by X-ray crystallographic methods. By... (Review)
Review
We have solved the structure of the Mahoney strain of type 1 and the Sabin (attenuated vaccine) strain of type 3 poliovirus by X-ray crystallographic methods. By providing a three-dimensional framework for the interpretation of a wealth of experimental data, the structures have yielded insight into the architecture and assembly of the virus particle, have provided information regarding the entry of virus into susceptible cells, and defined the sites on the virus particle that are recognized by neutralizing monoclonal antibodies. Thus locating mutations in variants selected for resistance to neutralizing monoclonal antibodies has defined three antigenic sites of the surface of the virion, and provided clues as to the mechanisms by which viruses escape neutralization. Finally, comparison of the structures of the two strains, together with analysis of sequences of many poliovirus strains, have begun to define the structural changes associated with serotypic differences between polioviruses.
Topics: Antigens, Viral; Models, Molecular; Models, Structural; Poliovirus; Protein Conformation; Viral Proteins
PubMed: 2569204
DOI: 10.1098/rstb.1989.0024 -
Biologicals : Journal of the... Dec 1993The three poliovirus serotypes are very stable. Breakthrough of the serotype barrier has never been observed in the natural evolution of poliovirus. This serotype... (Comparative Study)
Comparative Study Review
The three poliovirus serotypes are very stable. Breakthrough of the serotype barrier has never been observed in the natural evolution of poliovirus. This serotype stability contrasts with the high level of genomic and phenotypic variability that occurs within the bounds of serotype. The efficient control of poliomyelitis by immunization is based upon type-specific immunity and serotype stability. The development of attenuated strains by Albert Sabin was possible because of the high variability of poliovirus genomes. The three Sabin strains, one for each serotype, were selected as variants of non-attenuated wild polioviruses, and each represents a unique poliovirus genotype. A consequence of poliovirus variability is the polymorphic character of its genome. This polymorphism makes possible the identification of poliovirus genotypes upon which studies on poliovirus evolution, virologic surveillance, and poliomyelitis diagnostics are based. The antigenic and genomic peculiarities of the Sabin strains are used to distinguish them from wild polioviruses among field isolates. The mechanisms of poliovirus variation and their significance to the evolution of both wild and vaccine poliovirus strains are the subjects of this article. The natural evolution of polioviruses is discussed in the context of the global initiative to eradicate poliomyelitis, which relies on the worldwide use of Sabin's vaccine.
Topics: Animals; Antigens, Viral; Biological Evolution; Capsid; Genetic Variation; Genome, Viral; Humans; Mutation; Poliomyelitis; Poliovirus; Poliovirus Vaccine, Oral; Polymorphism, Genetic; Population Surveillance; RNA, Viral; Virulence
PubMed: 8024754
DOI: 10.1006/biol.1993.1099 -
Structure (London, England : 1993) Jul 1996A combination of structural and genetic studies of poliovirus suggests that the final stages of viral assembly lock the virus in a metastable structure primed to undergo... (Review)
Review
A combination of structural and genetic studies of poliovirus suggests that the final stages of viral assembly lock the virus in a metastable structure primed to undergo the receptor-catalyzed conformational changes required for cell entry. Future studies promise to provide detailed insights into the conformational dynamics of the virion during its life cycle.
Topics: Membrane Proteins; Models, Molecular; Molecular Structure; Poliovirus; RNA, Viral; Receptors, Virus; Structure-Activity Relationship
PubMed: 8805560
DOI: 10.1016/s0969-2126(96)00082-2 -
Structure (London, England : 1993) Jul 1996The cell receptor for poliovirus may be more than a simple "snare' that attaches virus to cells. Recent results indicate that receptor binding may cause conformational... (Review)
Review
The cell receptor for poliovirus may be more than a simple "snare' that attaches virus to cells. Recent results indicate that receptor binding may cause conformational changes in the virus that lead to uncoating of the viral RNA.
Topics: Capsid; Membrane Fusion; Membrane Proteins; Molecular Conformation; Poliovirus; RNA, Viral; Receptors, Virus
PubMed: 8805563
DOI: 10.1016/s0969-2126(96)00083-4 -
Biologicals : Journal of the... Mar 1997A new generation of tests to control live attenuated poliovirus vaccines are under development based on major advances in our understanding of the molecular basis of... (Review)
Review
A new generation of tests to control live attenuated poliovirus vaccines are under development based on major advances in our understanding of the molecular basis of attenuation and reversion to virulence of polioviruses. These include an alternative in vivo neurovirulence test in transgenic mice that express the human poliovirus receptor and a new in vitro test, the MAPREC (mutant analysis by polymerose chain reaction and restriction enzyme cleavage assay, that assesses consistency of production at a molecular level. Excellent progress is being made with both methods but neither is sufficiently developed yet for regulatory use. Critical review of existing control tests shows that the WHO neurovirulence test is well standardized and contributes significantly to the assessment of each batch. On the other hand, the current rct40 test is neither standardized nor particularly informative, though improvements could be made in both areas. The continued relevance of other marker tests such as the d or antigenic marker is doubtful. Potency, identity and thermal stability tests are crucial for control of the final trivalent vaccine.
Topics: Animals; Base Sequence; Genetic Markers; Humans; Mice; Molecular Sequence Data; Nucleic Acid Conformation; Poliovirus; Poliovirus Vaccine, Oral; Polymerase Chain Reaction; Quality Control; Vaccines, Attenuated
PubMed: 9167004
DOI: 10.1006/biol.1997.0055 -
Journal of Virological Methods Jun 2011The Global Polio Laboratory Network routinely uses poliovirus-specific PCR primers and probes to determine the serotype and genotype of poliovirus isolates obtained as...
The Global Polio Laboratory Network routinely uses poliovirus-specific PCR primers and probes to determine the serotype and genotype of poliovirus isolates obtained as part of global poliovirus surveillance. To provide detailed molecular epidemiologic information, poliovirus isolates are further characterized by sequencing the ~900-nucleotide region encoding the major capsid protein, VP1. It is difficult to obtain quality sequence information when clinical or environmental samples contain poliovirus mixtures. As an alternative to conventional methods for resolving poliovirus mixtures, sets of serotype-specific primers were developed for amplifying and sequencing the VP1 regions of individual components of mixed populations of vaccine-vaccine, vaccine-wild, and wild-wild polioviruses.
Topics: Capsid Proteins; DNA Primers; Humans; Poliovirus; Polymerase Chain Reaction; Sensitivity and Specificity; Sequence Analysis, DNA; Virology
PubMed: 21440569
DOI: 10.1016/j.jviromet.2011.03.020 -
Yakugaku Zasshi : Journal of the... Sep 1989Molecular genetic studies of the antigenicity and the attenuation phenotype of type 1 poliovirus were described. Antigenic sites were identified on the genome of type 1... (Review)
Review
Molecular genetic studies of the antigenicity and the attenuation phenotype of type 1 poliovirus were described. Antigenic sites were identified on the genome of type 1 poliovirus by the determination of nucleotide sequence of the genome of variants that were not neutralized by the neutralizing monoclonal antibodies. The solution of the crystal structure of poliovirus revealed that all mutations found as above are located at the surface of the virion and cluster into three distinct sites. These regions probably represent distinct antibody binding sites. To study expression of the attenuation phenotype of type 1 poliovirus, a number of recombinant polioviruses were constructed in vitro by using infectious complementary deoxyribonucleic acid clones of the virulent Mahoney and attenuated Sabin 1 strains of type 1 poliovirus. Biological tests including a monkey neurovirulence test were performed on the recombinants. The results indicated that the 5' noncoding region harbors a relatively strong determinant influencing the attenuation. Further studies revealed that an adenine residue (Mahoney type) at nucleotide position 480 importantly contribute to the expression of the neurovirulence phenotype. However, a guanine residue (Sabin 1 type) at position 480 was not sufficient for full expression of the attenuation phenotype encoded by this genome region. These results suggested that the expression of the attenuation phenotype depends on the highly ordered structure formed in the 5' noncoding sequence and that the formation of such a structure is possibly influenced by the nucleotide position 480. To investigate the structure and function of the 5' noncoding region, many insertion and deletion sequences were introduced into the genome region. Replication processes of the mutants were analysed and second-site mutations in the genome of the variants that partially restored the phenotypes of the parental viruses were identified. The results indicated that interactions between different loci, for example at around positions 200 and 500, are important for maintaining the viral replication efficiency.
Topics: Animals; Cloning, Molecular; DNA, Viral; Epitopes; Genes, Viral; Mutation; Poliovirus; Virus Replication
PubMed: 2481725
DOI: 10.1248/yakushi1947.109.9_622