title: Trans-complementation of E1-deleted adenovirus: a new vector to reduce the possibility of codissemination of wild-type and recombinant adenoviruses.
abstract: Treatment of cystic fibrosis by gene therapy will require the development of vectors capable of efficient and safe transfer of a functional cystic fibrosis transmembrane conductance regulator (CFTR) cDNA to airway epithelia. To achieve this goal, replication-deficient (E1-) adenoviruses (Ad) are promising vectors. We have previously demonstrated efficient CFTR gene delivery to the airways of cotton rats and rhesus monkeys using a replication-deficient adenovirus, Ad-CFTR. Here, we have investigated an important safety issue, the interaction between the vector and wild-type virus which can provide the missing E1 function in trans. We show that Ad5 can mobilize the defective Ad-CFTR genome in vitro and in cotton rats. However, the extent of the complementation in vivo by wild-type virus is limited because no additional spreading or shedding of Ad-CFTR to trachea, lungs, and stools is elicited. To attenuate Ad-CFTR further, a mutation was introduced in the cis-acting regulatory sequences that control the encapsidation of the viral genome. We demonstrate that when cells are coinfected with wild-type virus and the new attenuated vector, the viral DNA containing the natural encapsidation sequences is preferentially packaged, leading to a rapid dilution of the recombinant virus.
authors.affiliation: Transgène S.A. Strasbourg, France.
authors.forename: J L
authors.initials: JL
authors.lastname: Imler
authors.forename: A
authors.initials: A
authors.lastname: Bout
authors.forename: D
authors.initials: D
authors.lastname: Dreyer
authors.forename: A
authors.initials: A
authors.lastname: Dieterlé
authors.forename: H
authors.initials: H
authors.lastname: Schultz
authors.forename: D
authors.initials: D
authors.lastname: Valerio
authors.forename: M
authors.initials: M
authors.lastname: Mehtali
authors.forename: A
authors.initials: A
authors.lastname: Pavirani
mesh_terms: D000256:Adenoviridae / Q000235:genetics*; D017498:Adenovirus E1 Proteins / Q000235:genetics*; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D003550:Cystic Fibrosis / Q000628:therapy*; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics*; D004279:DNA, Viral / Q000235:genetics; D003673:Defective Viruses / Q000235:genetics; D005260:Female; D005816:Genetic Complementation Test; D015316:Genetic Therapy; D005822:Genetic Vectors; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides; D017384:Sequence Deletion; D016205:Sigmodontinae
chemical_list: D017498:Adenovirus E1 Proteins; C505032:CFTR protein, human; D004279:DNA, Viral; D009838:Oligodeoxyribonucleotides; D019005:Cystic Fibrosis Transmembrane Conductance Regulator