Limits...
The highly attenuated oncolytic recombinant vaccinia virus GLV-1h68: comparative genomic features and the contribution of F14.5L inactivation.

Zhang Q, Liang C, Yu YA, Chen N, Dandekar T, Szalay AA - Mol. Genet. Genomics (2009)

Bottom Line: The reduced pathogenicity of GLV-1h68 is confirmed in male mice bearing C6 rat glioma and in immunocompetent mice bearing B16-F10 murine melanoma.The contribution of foreign gene expression cassettes in the F14.5L, J2R and A56R loci is analyzed, in particular the contribution of F14.5L inactivation to the reduced virulence is demonstrated by comparing the virulence of GLV-1h68 with its F14.5L- and revertant viruses.GLV-1h68 is a promising engineered VACV variant for anticancer therapy with tumor-specific replication, reduced pathogenicity and benign tissue tropism.

View Article: PubMed Central - PubMed

Affiliation: Genelux Corporation, San Diego Science Center, 3030 Bunker Hill St., Ste. 310, San Diego, CA 92109, USA.

ABSTRACT
As a new anticancer treatment option, vaccinia virus (VACV) has shown remarkable antitumor activities (oncolysis) in preclinical studies, but potential infection of other organs remains a safety concern. We present here genome comparisons between the de novo sequence of GLV-1h68, a recombinant VACV, and other VACVs. The identified differences in open reading frames (ORFs) include genes encoding host-range selection, virulence and immune modulation proteins, e.g., ankyrin-like proteins, serine proteinase inhibitor SPI-2/CrmA, tumor necrosis factor (TNF) receptor homolog CrmC, semaphorin-like and interleukin-1 receptor homolog proteins. Phylogenetic analyses indicate that GLV-1h68 is closest to Lister strains but has lost several ORFs present in its parental LIVP strain, including genes encoding CrmE and a viral Golgi anti-apoptotic protein, v-GAAP. The reduced pathogenicity of GLV-1h68 is confirmed in male mice bearing C6 rat glioma and in immunocompetent mice bearing B16-F10 murine melanoma. The contribution of foreign gene expression cassettes in the F14.5L, J2R and A56R loci is analyzed, in particular the contribution of F14.5L inactivation to the reduced virulence is demonstrated by comparing the virulence of GLV-1h68 with its F14.5L- and revertant viruses. GLV-1h68 is a promising engineered VACV variant for anticancer therapy with tumor-specific replication, reduced pathogenicity and benign tissue tropism.

Show MeSH

Related in: MedlinePlus

Replication and pathogenicity of different VACV strains. a Genetic constructs for different VACV strains (reproduced from Zhang et al. 2007). A single base substitution created a premature stop codon; therefore, the TK gene in LIVP wt or GLV-1d27 was naturally inactivated. pSEL, VACV synthetic early late promoter; p7.5 and p11K, VACV 7.5 early/late and 11k promoters; TFR, human transferrin receptor. b The replication of different VACV strains was studied in various cell cultures. c The pathogenicity was evaluated by change in body weight after a single, intravenous injection of each individual virus at 107 pfu per mouse, in nude mice bearing C6 glioma, and C57BL/6 mice bearing B16-F10 melanoma. Change of body weight (%) was calculated as follows: [(b′ − t′) − (b − t)] × 100/(b − t), where b and t are the body weight and tumor weight (estimated by tumor size; 1 cm3 = 1 g) on the day of virus injection, and b′ and t′ are the corresponding weights on the day of monitoring. The average weight change for each group is presented
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2746888&req=5

Fig5: Replication and pathogenicity of different VACV strains. a Genetic constructs for different VACV strains (reproduced from Zhang et al. 2007). A single base substitution created a premature stop codon; therefore, the TK gene in LIVP wt or GLV-1d27 was naturally inactivated. pSEL, VACV synthetic early late promoter; p7.5 and p11K, VACV 7.5 early/late and 11k promoters; TFR, human transferrin receptor. b The replication of different VACV strains was studied in various cell cultures. c The pathogenicity was evaluated by change in body weight after a single, intravenous injection of each individual virus at 107 pfu per mouse, in nude mice bearing C6 glioma, and C57BL/6 mice bearing B16-F10 melanoma. Change of body weight (%) was calculated as follows: [(b′ − t′) − (b − t)] × 100/(b − t), where b and t are the body weight and tumor weight (estimated by tumor size; 1 cm3 = 1 g) on the day of virus injection, and b′ and t′ are the corresponding weights on the day of monitoring. The average weight change for each group is presented

Mentions: In our previous studies (Zhang et al. 2007), GLV-1h68 was evaluated in human breast tumor cell line GI-101A to examine whether insertions in the F14.5L, J2R or A56R locus affected its activity. In this study, complementary to the broad comparison of genomic and pathogenomic features just detailed, infection studies were carried out in further tumor cell lines to compare the infectivity and replication of individual recombinant viruses (Fig. 5b). In CV-1 cells all recombinant viruses replicated very well, and showed comparable yield, similar to wt-WR and wt-LIVP viruses. In C6 glioma cells, however, the recombinant viruses, and particularly GLV-1h68, showed a reduced replication of up to 102-fold, compared to wt-LIVP (Fig. 5b). Cells of mouse origins required a higher MOI for detectable infection, which was true for both primary MEFs and the tumor cell line B16-F10. At an MOI of 0.01, the wt-LIVP replicated fairly well in MEFs, but the three recombinant LIVP viruses did not replicate. In B16-F10 melanoma cells, all viruses showed limited infection and replication (Fig. 5b).Fig. 5


The highly attenuated oncolytic recombinant vaccinia virus GLV-1h68: comparative genomic features and the contribution of F14.5L inactivation.

Zhang Q, Liang C, Yu YA, Chen N, Dandekar T, Szalay AA - Mol. Genet. Genomics (2009)

Replication and pathogenicity of different VACV strains. a Genetic constructs for different VACV strains (reproduced from Zhang et al. 2007). A single base substitution created a premature stop codon; therefore, the TK gene in LIVP wt or GLV-1d27 was naturally inactivated. pSEL, VACV synthetic early late promoter; p7.5 and p11K, VACV 7.5 early/late and 11k promoters; TFR, human transferrin receptor. b The replication of different VACV strains was studied in various cell cultures. c The pathogenicity was evaluated by change in body weight after a single, intravenous injection of each individual virus at 107 pfu per mouse, in nude mice bearing C6 glioma, and C57BL/6 mice bearing B16-F10 melanoma. Change of body weight (%) was calculated as follows: [(b′ − t′) − (b − t)] × 100/(b − t), where b and t are the body weight and tumor weight (estimated by tumor size; 1 cm3 = 1 g) on the day of virus injection, and b′ and t′ are the corresponding weights on the day of monitoring. The average weight change for each group is presented
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2746888&req=5

Fig5: Replication and pathogenicity of different VACV strains. a Genetic constructs for different VACV strains (reproduced from Zhang et al. 2007). A single base substitution created a premature stop codon; therefore, the TK gene in LIVP wt or GLV-1d27 was naturally inactivated. pSEL, VACV synthetic early late promoter; p7.5 and p11K, VACV 7.5 early/late and 11k promoters; TFR, human transferrin receptor. b The replication of different VACV strains was studied in various cell cultures. c The pathogenicity was evaluated by change in body weight after a single, intravenous injection of each individual virus at 107 pfu per mouse, in nude mice bearing C6 glioma, and C57BL/6 mice bearing B16-F10 melanoma. Change of body weight (%) was calculated as follows: [(b′ − t′) − (b − t)] × 100/(b − t), where b and t are the body weight and tumor weight (estimated by tumor size; 1 cm3 = 1 g) on the day of virus injection, and b′ and t′ are the corresponding weights on the day of monitoring. The average weight change for each group is presented
Mentions: In our previous studies (Zhang et al. 2007), GLV-1h68 was evaluated in human breast tumor cell line GI-101A to examine whether insertions in the F14.5L, J2R or A56R locus affected its activity. In this study, complementary to the broad comparison of genomic and pathogenomic features just detailed, infection studies were carried out in further tumor cell lines to compare the infectivity and replication of individual recombinant viruses (Fig. 5b). In CV-1 cells all recombinant viruses replicated very well, and showed comparable yield, similar to wt-WR and wt-LIVP viruses. In C6 glioma cells, however, the recombinant viruses, and particularly GLV-1h68, showed a reduced replication of up to 102-fold, compared to wt-LIVP (Fig. 5b). Cells of mouse origins required a higher MOI for detectable infection, which was true for both primary MEFs and the tumor cell line B16-F10. At an MOI of 0.01, the wt-LIVP replicated fairly well in MEFs, but the three recombinant LIVP viruses did not replicate. In B16-F10 melanoma cells, all viruses showed limited infection and replication (Fig. 5b).Fig. 5

Bottom Line: The reduced pathogenicity of GLV-1h68 is confirmed in male mice bearing C6 rat glioma and in immunocompetent mice bearing B16-F10 murine melanoma.The contribution of foreign gene expression cassettes in the F14.5L, J2R and A56R loci is analyzed, in particular the contribution of F14.5L inactivation to the reduced virulence is demonstrated by comparing the virulence of GLV-1h68 with its F14.5L- and revertant viruses.GLV-1h68 is a promising engineered VACV variant for anticancer therapy with tumor-specific replication, reduced pathogenicity and benign tissue tropism.

View Article: PubMed Central - PubMed

Affiliation: Genelux Corporation, San Diego Science Center, 3030 Bunker Hill St., Ste. 310, San Diego, CA 92109, USA.

ABSTRACT
As a new anticancer treatment option, vaccinia virus (VACV) has shown remarkable antitumor activities (oncolysis) in preclinical studies, but potential infection of other organs remains a safety concern. We present here genome comparisons between the de novo sequence of GLV-1h68, a recombinant VACV, and other VACVs. The identified differences in open reading frames (ORFs) include genes encoding host-range selection, virulence and immune modulation proteins, e.g., ankyrin-like proteins, serine proteinase inhibitor SPI-2/CrmA, tumor necrosis factor (TNF) receptor homolog CrmC, semaphorin-like and interleukin-1 receptor homolog proteins. Phylogenetic analyses indicate that GLV-1h68 is closest to Lister strains but has lost several ORFs present in its parental LIVP strain, including genes encoding CrmE and a viral Golgi anti-apoptotic protein, v-GAAP. The reduced pathogenicity of GLV-1h68 is confirmed in male mice bearing C6 rat glioma and in immunocompetent mice bearing B16-F10 murine melanoma. The contribution of foreign gene expression cassettes in the F14.5L, J2R and A56R loci is analyzed, in particular the contribution of F14.5L inactivation to the reduced virulence is demonstrated by comparing the virulence of GLV-1h68 with its F14.5L- and revertant viruses. GLV-1h68 is a promising engineered VACV variant for anticancer therapy with tumor-specific replication, reduced pathogenicity and benign tissue tropism.

Show MeSH
Related in: MedlinePlus