Development and application of a minimal-adenoviral vector system for gene therapy of hemophilia A.
To achieve efficient delivery and sustained expression of the human factor VIII cDNA in vivo, a minimal-adenoviral (mini-Ad) vector system was developed. The system is composed of a mini-Ad vector with essential cis-elements (less than 1 kb) of the viral genome, an E1-deleted ancillary Ad with packaging attenuation, and an E1-complementing production cell line. Based on this system, MiniAdFVIII was generated to deliver a 27 kb expression cassette consisting of a full-length human factor VIII cDNA flanked by human albumin promoter and genomic sequences. The MiniAdFVIII vector mediated expression of functional human factor VIII in HepG2 and 293 cells. A single-dose intravenous injection of 10(11) viral particles in hemophilic mice of MiniAdFVIII produced a sustained high-level expression of human factor VIII (at 100-800 ng/ml up to 369 days) which corrected the FVIII-deficient phenotype. Safety studies of MiniAdFVIII showed that there were no significant toxic effects in mice and dogs after single intravessel doses of up to 3 x 10(11) and 6 x 10(12) viral particles, respectively. Studies for developing the MiniAdFVIII vector with a site-specific integration mechanism and progress in the development of a human factor VIII-tolerized mouse model for pre-clinical studies of MiniAdFVIII are reported. Further pre-clinical studies and product development of MiniAdFVIII for clinical trials are also discussed.
Zhang
W W
WW
GenStar Therapeutics Corporation, San Diego, CA 92121, USA.
Josephs
S F
SF
Zhou
J
J
Fang
X
X
Alemany
R
R
Balagué
C
C
Dai
Y
Y
Ayares
D
D
Prokopenko
E
E
Lou
Y C
YC
Sethi
E
E
Hubert-Leslie
D
D
Kennedy
M
M
Ruiz
L
L
Rockow-Magnone
S
S
D000256:Adenoviridae / Q000235:genetics*; D000818:Animals; D004195:Disease Models, Animal; D004285:Dogs; D005169:Factor VIII / Q000235:genetics*; D018014:Gene Transfer Techniques; D015316:Genetic Therapy; D005822:Genetic Vectors; D006467:Hemophilia A / Q000628:therapy*; D006801:Humans; D051379:Mice
D005169:Factor VIII