Multiple amino acids in the glycoprotein of rabies virus are responsible for pathogenicity in adult mice

Takayama-Ito, Mutsuyo; Ito, Naoto; Yamada, Kentaro; Sugiyama, Makoto; Minamoto, Nobuyuki

doi:10.1016/j.virusres.2005.08.004

Cited by 70 publications

(52 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…(ii) The conclusion that pathogenicity inversely correlates with glycoprotein expression level was originally derived by comparing N2c and the closely related B2c variant of the CVS-24 RV strain. (iii) N2c is a highly pathogenic and neurotropic virus and is therefore better suited to analysis of attenuation of pathogenic RV than the already highly attenuated SAD and NC-HL strains, which served as a genetic background in earlier studies of the RV glycoprotein and its role in pathogenicity (21,34,36).…”

Section: Resultsmentioning

confidence: 99%

Rabies Virus (RV) Glycoprotein Expression Levels Are Not Critical for Pathogenicity of RV

Wirblich

Schnell

2011

J Virol

View full text Add to dashboard Cite

Previous comparisons of different rabies virus (RV) strains suggested an inverse relationship between pathogenicity and the amount of glycoprotein produced in infected cells. In order to provide more insight into this relationship, we pursued an experimental approach that allowed us to alter the glycoprotein expression level without altering the glycoprotein sequence, thereby eliminating the contribution of amino acid changes to differences in viral virulence. To this end, we constructed an infectious clone of the highly pathogenic rabies virus strain CVS-N2c and replaced its cognate glycoprotein gene with synthetic versions in which silent mutations were introduced to replace wild-type codons with the most or least frequently used synonymous codons. A recombinant N2c variant containing the fully codon-optimized G gene and three variants carrying a partially codon-deoptimized G gene were recovered on mouse neuroblastoma cells and shown to express 2-to 3-fold more and less glycoprotein, respectively, than wild-type N2c. Pathogenicity studies in mice revealed the WT-N2c virus to be the most pathogenic strain. Variants containing partially codon-deoptimized glycoprotein genes or the codon-optimized gene were less pathogenic than WT-N2c but still caused significant mortality. We conclude that the expression level of the glycoprotein gene does have an impact on pathogenicity but is not a dominant factor that determines pathogenicity. Thus, strategies such as changes in codon usage that aim solely at altering the expression level of the glycoprotein gene do not suffice to render a pathogenic rabies virus apathogenic and are not a viable and safe approach for attenuation of a pathogenic strain.

show abstract

Section: Resultsmentioning

confidence: 99%

Rabies Virus (RV) Glycoprotein Expression Levels Are Not Critical for Pathogenicity of RV

Wirblich

Schnell

2011

J Virol

View full text Add to dashboard Cite

show abstract

“…2). Some amino acids in the G gene of fixed strains affecting viral pathogenicity (i.e., Asp 255 , Ile 268, and Arg 333 ) were conserved; however, Ser 242 was encoded in the BR-DR1 and BR-AL1 isolates, while Ala 242 was encoded in the BR-Pfx1 isolate and PV strain [31,33]. Two potential N-glycosylation sites at positions 37-39 and 319-321 were found in BR-DR1 and BR-AL1.…”

Section: Resultsmentioning

confidence: 99%

Determination and Molecular Analysis of the Complete Genome Sequence of Two Wild-Type Rabies Viruses Isolated from a Haematophagous Bat and a Frugivorous Bat in Brazil

Mochizuki

Kobayashi

Sato

et al. 2011

The Journal of Veterinary Medical Science

View full text Add to dashboard Cite

ABSTRACT. The complete genome sequences of two Brazilian wild-type rabies viruses (RABV), a BR-DR1 isolate from a haematophagous bat (Desmodus rotundus) and a BR-AL1 isolate from a frugivorous bat (Artibeus lituratus), were determined. The genomes of the BR-DR1 and BR-AL1 had 11,923 and 11,922 nt, respectively, and both encoded the five standard genes of rhabdoviruses. The complete nucleotide sequence identity between the BR-DR1 and BR-AL1 isolates was 97%. The BR-DR1 and BR-AL1 isolates had some conserved functional sites revealed by the fixed isolates, whereas both isolates had unique amino acid substitutions in the antigenic region IV of the nucleocapsid gene. Therefore, it is speculated that both isolates were nearly identical in virologic character. According to our phylogenetic analysis based on the complete genomes, both isolates belonged to genotype 1, and to the previously defined "vampire batrelated RABV lineage" which consisted of mainly D. rotundus-and A. lituratus-isolates; however, a branch pattern with high bootstrap values suggested that BR-DR1 was more closely related to the 9001FRA isolate, which was collected from a dog bitten by a bat in French Guiana, than to BR-AL1. This result suggests that the vampire bat-related RABV lineage includes Brazilian vampire bat and Brazilian frugivorous bat RABV and is further divided into Brazilian vampire bat and Brazilian frugivorous bat RABV sub-lineages. The phylogenetic analysis based on the complete genomes was valuable in discriminating among very closely related isolates.KEY WORDS: complete genome, frugivorous bat, genetic analysis, haematophagous bat, wild-type rabies virus.

show abstract

“…WHO recommends genetic characterization of vaccine strain at complete genome level or more particularly for G and N genes [35]. The G protein has role in cell attachment, induction of neutralizing antibodies and cell mediated immune response [31]. Therefore, any difference in this gene between vaccine strain and wild viruses should be critically studied and analysed.…”

Section: Discussionmentioning

confidence: 99%

Molecular and immunogenic characterization of BHK-21 cell line adapted CVS-11 strain of rabies virus and future prospect in vaccination strategy

et al. 2015

View full text Add to dashboard Cite

Development of a cost effective quality vaccine is a key issue in rabies control programme in developing countries. With this perspective, in the present study, challenge virus standard (CVS)-11 strain of rabies virus was adapted to grow in BHK-21 cells, characterized, compared with other viruses including global vaccine strains and field isolates from Indian subcontinent and China at molecular level. This cell adapted virus was evaluated for the production of cost effective veterinary vaccine. The maximum virus titre achieved was 10 7 fluorescent focus unit (FFU)/mL at 10th passage level. There was no nucleotide difference in the nucleoprotein (N) and glycoprotein (G) genes after adaptation in cell line. Phylogenetic analysis showed that adapted virus was grouped with global vaccine strains, closest being with other CVS strains but distinct from the Indian field isolates. Global vaccine strains including cell adapted CVS-11 virus have 83-87 % identity at nucleotide level of G gene with Indian field viruses. Growth kinetics of cell culture adapted virus showed that the optimum virus titer (around 10 7 FFU/mL) could be obtained at around 48 h post infection by cocultivation method using 0.1 multiplicity of infection inoculums at 37°C. These findings can be used for up scaling of vaccine production. The protective efficacy of test vaccine produced using 10 6.95 FFU/mL cell culture harvest showed 1.17 IU/mL relative potency by NIH test. Further, adapted virus was found to be suitable for use in rapid fluorescent focus inhibition test.

show abstract

Multiple amino acids in the glycoprotein of rabies virus are responsible for pathogenicity in adult mice

Cited by 70 publications

References 39 publications

Rabies Virus (RV) Glycoprotein Expression Levels Are Not Critical for Pathogenicity of RV

Rabies Virus (RV) Glycoprotein Expression Levels Are Not Critical for Pathogenicity of RV

Determination and Molecular Analysis of the Complete Genome Sequence of Two Wild-Type Rabies Viruses Isolated from a Haematophagous Bat and a Frugivorous Bat in Brazil

Molecular and immunogenic characterization of BHK-21 cell line adapted CVS-11 strain of rabies virus and future prospect in vaccination strategy

Contact Info

Product

Resources

About