Self-complementary recombinant adeno-associated virus (scAAV) vectors promote efficient transduction independently of DNA synthesis.
Adeno-associated virus (AAV) vectors package single-stranded genomes and require host-cell synthesis of the complementary strand for transduction. However, when the genome is half wild-type size, AAV can package either two copies, or dimeric inverted repeat DNA molecules. Dimeric, or self-complementary molecules (scAAV) should spontaneously reanneal, alleviating the requirement for host-cell DNA synthesis. We generated and characterized scAAV vectors in order to bypass the rate-limiting step of second-strand synthesis. In vitro, scAAV vectors were five- to 140-fold more efficient transducing agents than conventional rAAV, with a 5.9:1 particle to transducing unit ratio. This efficiency is neither greatly increased by co-infection with Ad, nor inhibited by hydroxyurea, demonstrating that transduction is independent of DNA synthesis. In vivo, scAAV expressing erythropoietin resulted in rapid and higher levels of hematocrit than a conventional single-stranded vector. These novel scAAV vectors represent a biochemical intermediate in rAAV transduction and should provide new insights into the biology of vector transduction.
McCarty
D M
DM
UNC Gene Therapy Center, University of North Carolina at Chapel Hill, NC, USA.
Monahan
P E
PE
Samulski
R J
RJ
D000818:Animals; D002460:Cell Line; D018076:DNA, Complementary; D004279:DNA, Viral; D000229:Dependovirus / Q000235:genetics*; D004921:Erythropoietin / Q000235:genetics; D015870:Gene Expression; D005818:Genetic Engineering; D005822:Genetic Vectors / Q000494:pharmacology*; D049452:Green Fluorescent Proteins; D006367:HeLa Cells; D006400:Hematocrit; D006801:Humans; D008099:Liver / Q000378:metabolism; D008164:Luminescent Proteins / Q000235:genetics; D051379:Mice; D008807:Mice, Inbred BALB C; D014161:Transduction, Genetic
D018076:DNA, Complementary; D004279:DNA, Viral; D008164:Luminescent Proteins; D004921:Erythropoietin; D049452:Green Fluorescent Proteins