Multigene expression from a replicating adenovirus using native viral promoters.
We have developed a novel therapeutic gene delivery system for oncolytic adenoviruses that takes advantage of the endogenous gene expression machinery (promoters, splicing, polyadenylation signals) of the E3 transcription unit for gene delivery. In this work, we use two sites in the E3 region (6.7 K/gp19K and ADP sites) to demonstrate that (1) multiple therapeutic genes (MCP-3, TNFalpha) can be expressed from a single replicating Ad, (2) timing of expression of these therapeutic genes mimics that of the E3 region genes they replaced, (3) expression of the remaining genes in the complex E3 transcription unit is maintained, and (4) the multigene-expressing virus retains replication competence and ability to induce classical adenovirus cytopathic effects that parallel those of the parental adenovirus (ONYX-320). This system conserves the DNA packaging capacity of the size-constrained viral genome for therapeutic genes and can potentially be used to link therapeutic transgene expression to tumor-restricted viral replication. Potential clinical implications are discussed.
Bauzon
Maxine
M
Onyx Pharmaceuticals, 3031 Research Drive, Richmond, California 94806, USA.
Castro
Daniel
D
Karr
Michael
M
Hawkins
Lynda K
LK
Hermiston
Terry W
TW
D000256:Adenoviridae / Q000235:genetics* / Q000378:metabolism; D017503:Adenovirus E3 Proteins / Q000235:genetics / Q000378:metabolism; D054410:Chemokine CCL7; D016207:Cytokines; D015967:Gene Expression Regulation, Viral; D005822:Genetic Vectors; D006801:Humans; D018945:Monocyte Chemoattractant Proteins / Q000235:genetics / Q000378:metabolism; D011401:Promoter Regions, Genetic; D019076:Transgenes; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism; D014779:Virus Replication
D017503:Adenovirus E3 Proteins; C515450:CCL7 protein, human; D054410:Chemokine CCL7; D016207:Cytokines; D018945:Monocyte Chemoattractant Proteins; D014409:Tumor Necrosis Factor-alpha