Characterization of human adenovirus 35 and derivation of complex vectors.
BACKGROUND
Replication-deficient recombinant adenoviral vectors based on human serotype 35 (Ad35) are desirable due to the relatively low prevalence of neutralizing antibodies in the human population. The structure of the viral genome and life cycle of Ad35 differs from the better characterized Ad5 and these differences require differences in the strategies for the generation of vectors for gene delivery.


RESULTS
Sequences essential for E1 and E4 function were identified and removed and the effects of the deletions on viral gene transcription were determined. In addition, the non-essential E3 region was deleted from rAd35 vectors and a sequence was found that did not have an effect on viability but reduced viral fitness. The packaging capacity of rAd35 was dependent on pIX and vectors were generated with stable genome sizes of up to 104% of the wild type genome size. These data were used to make an E1-, E3-, E4-deleted rAd35 vector. This rAd35 vector with multiple gene deletions has the advantages of multiple blocks to viral replication (i.e., E1 and E4 deletions) and a transgene packaging capacity of 7.6 Kb, comparable to rAd5 vectors.


CONCLUSIONS
The results reported here allow the generation of larger capacity rAd35 vectors and will guide the derivation of adenovirus vectors from other serotypes.
Department of Research, GenVec, Inc, Gaithersburg, MD 20874, USA.
Duncan
D
McVey
Mohammed
M
Zuber
Damodar
D
Ettyreddy
Christopher D
CD
Reiter
Douglas E
DE
Brough
Gary J
GJ
Nabel
C Richter
CR
King
Jason G D
JG
Gall
D017498:Adenovirus E1 Proteins / Q000235:genetics / Q000502:physiology; D017503:Adenovirus E3 Proteins / Q000235:genetics / Q000502:physiology; D017504:Adenovirus E4 Proteins / Q000235:genetics / Q000502:physiology; D000260:Adenoviruses, Human / Q000235:genetics / Q000502:physiology*; D017353:Gene Deletion; D015316:Genetic Therapy / Q000379:methods; D005822:Genetic Vectors; D016679:Genome, Viral; D006801:Humans; D050296:Microbial Viability; D014158:Transcription, Genetic; D019065:Virus Assembly; D014779:Virus Replication
D017498:Adenovirus E1 Proteins; D017503:Adenovirus E3 Proteins; D017504:Adenovirus E4 Proteins