Efficiency of delivery of DNA to cells by bovine papillomavirus type-1 L1/L2 pseudovirions.
To investigate the efficiency of encapsidation of plasmid by papillomavirus virus-like particles (PV VLPs), and the infectivity of the resultant PV pseudovirions, Cos-1 cells were transfected with an 8-kb plasmid incorporating a green fluorescent protein (GFP) reporter gene (pGSV), and infected with bovine PV (BPV-1) L1/L2 recombinant vaccinia virus to produce BPV1 pseudovirions. Approximately 1 in 1.5 x 10(4) of dense (1.35 g/ml) PV pseudovirions and 0.3 in 10(4) of less-dense (1.29 g/ml) pseudovirions packaged an intact pGSV plasmid. The majority (>75%) of packaged plasmids contained deletions, and the deletions affected all tested genes. After exposure of Cos-1 cells to BPV-1 pseudovirions at an MOI of 40,000:1, 6% of cells expressed GFP, giving a calculated efficiency of delivery of the pGSV plasmid, by pseudovirions which had packaged an intact plasmid, of approximately 5%. Plasmid delivery was not effected by purified pGSV plasmid, was blocked by antiserum against BPV-1, and was not blocked by DNase treatment of pseudovirions, confirming that delivery was mediated by DNA within the pseudovirion. We conclude that a major limitation to the use of PV pseudovirions as a gene delivery system is that intact plasmid DNA is not efficiently selected for packaging by VLPs in cell-based pseudovirions production systems.
Liu
Y
Y
Center for Immunology and Cancer Research, University of Queensland, Princess Alexandra Hospital, Woolloongabba, Australia.
Frazer
I H
IH
Liu
W J
WJ
Liu
X S
XS
McMillan
N
N
Zhao
K N
KN
D000818:Animals; D052688:Bovine papillomavirus 1 / Q000502:physiology*; D019556:COS Cells; D002213:Capsid / Q000502:physiology*; D036022:Capsid Proteins; D004247:DNA / Q000378:metabolism*; D014771:Virion / Q000502:physiology*; D019065:Virus Assembly
D036022:Capsid Proteins; C085217:L1 protein, Bovine papillomavirus; C085218:L2 protein, Bovine papillomavirus; D004247:DNA