Ability of a chimeric cAMP-responsive promoter to confer pharmacologic control of CFTR cDNA expression and cAMP-mediated Cl- secretion.
Based on the theoretical concern that chronic over-expression of the exogenous CFTR protein could be associated with adverse effects following gene transfer, we have constructed a replication-deficient adenovirus (Ad) vector containing the normal human CFTR cDNA controlled by a chimeric, cAMP-regulatable promoter responsive to agents that elevate intracellular cAMP levels. Studies with the IB3 human CF-derived respiratory epithelial line as a model target for CF gene therapy and forskolin to elevate cAMP levels demonstrated that following infection with the AdCF126(CRE8) CFTR vector, there was a marked increase in CFTR mRNA levels after forskolin addition. There was an associated correction of cAMP-mediated Cl- secretion that could be further increased with additional forskolin. cAMP-mediated Cl- secretion was corrected with vector doses as low as 0.2 MOI, a dose that can be achieved in vivo in humans. These observations suggest the feasibility of using a regulatable promoter for gene therapy for CF, with the promoter and gene product stimulated by the same class of pharmacologic agents.
Suzuki
M
M
Division of Pulmonary and Critical Care Medicine, New York Hospital, Cornell Medical Center, NY 10021, USA.
Singh
R N
RN
Crystal
R G
RG
D000256:Adenoviridae; D000838:Anions; D002460:Cell Line; D002712:Chlorides / Q000378:metabolism; D005576:Colforsin / Q000627:therapeutic use*; D003131:Combined Modality Therapy; D000242:Cyclic AMP / Q000378:metabolism; D003550:Cystic Fibrosis / Q000378:metabolism / Q000503:physiopathology / Q000628:therapy*; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics*; D018076:DNA, Complementary / Q000235:genetics; D005786:Gene Expression Regulation; D018014:Gene Transfer Techniques; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors; D006801:Humans; D011401:Promoter Regions, Genetic
D000838:Anions; C505032:CFTR protein, human; D002712:Chlorides; D018076:DNA, Complementary; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; D005576:Colforsin; D000242:Cyclic AMP