Recombination adenovirus vector replication

Lemarchand, P., Jones, M., Yamada, I. and Crystal, R. G. (1993). In vivo gene-transfer and expression in normal, uninjured blood-vessels using replication deficient recombinant adenovirus vectors. Clin. Res. 41(2), A202. 

MuhlhauserJ, Jones M, Yamada I, et al, Safety and efficacy of in vivo gene transfer into the porcine heart with replication-deficient, recombinant adenovirus vectors, Gene Ther 1996 3(2) 145-1 53. 

Wiknott, R.W. and Whitsett, J., A phase 1 study of gene therapy of cystic fibrosis utilizing a replication deficient recombinant adenovirus vector to deliver the human cystic fibrosis trans-membrane conductance regulator cDNA to the airways. Bethesda, MD, Office of Recombinant DNA Activity, NIH. 

The ability of two soluble chitosan formulations (chitosan and glycol chitosan) to improve the immunogenicity of an intranasaUy administered replication-defective human adenovirus type 5 expressing BoHV-1 glycoprotein D-based vaccine was investigated in cattle (Vila et al. 2004). It was reported that soluble formulation of glycol chitosan has promising potential use as an intranasal adjuvant for recombinant viral vector vaccines in cattle. 

Vector Construction. Construction of the recombinant replication incompetent (El/2 deleted) adenovirus serotype 5 (Ad5) expressing the human FGF-4 cDNA required three components the FGF-4 transgene, a plasmid shuttle vector to carry the transgene as well as 5 Ad5 sequences, and a second plasmid carrying the bulk of the Ad5 genome. 

In creating vectors fiom a human adenovirus a number of issues were considered (16). The vector must be isolated as a distinet moleeular entity fiee of contamination fiom adventitious agents and other undesired forms of the virus. Vector creation should be sim)4e and scalable and yields of the resulting veetor should be high. Finally, for gene replacement, it is preferable that the recombinant virus does not replicate or express viral genes. 

The presence of replication- competent virus in the vector preparation is problematic, since it could be associated with increased toxicity and may lacilitate the spread of the recombinant in vivo (18-20). Replication-competent adenovirus occurs by either cross contamination of the initial plaque with replication-competent vims from an adj acent plaque or reversion of the E1 deletion during the propagation of the recombinant by homologous recombination between sequences in the vector flanking the El deletion and the transfected El sequences in 293 cells. 

A major advance in replication-defective adenoviruses is the development of methods for creating recombinant viruses from distinct molecular clones in which the entire genome of the vector has been subcloned into a prokaryotic or invertebrate host. This has now been accomplished in a number of systems including yeast artificial chromosomes (21), cosmids (22), and bacterial plasmids (23-25). The subsequent discussion will focus on methods in which the adenoviral genome is subeloned in its entirety into bacterial plasmids,... 

Juillard V, Villefioy P, Godfiin D, Pavitani A, Venet A, Guillet JG. Long-term humoral and cellular immunity induced by a single immunization with replication-defective adenovirus recombinant vector. EurJ Immunol 1995 25 3467-3473. 

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