Efficacy of adenovirus vectors containing different cftr
transcriptional cassettes to correct electrolyte and fluid transport
in cultured cf airway epithelial cells.
Jiang, Canwen, Sean P. O'connor, Donna Armentano, Patricia B.
Berthelette, Susan C. Schiavi, Douglas M. Jefferson, Alan E. Smith,
Samuel C. Wadsworth, and Seng H. Cheng.
Genzyme Corporation, One Mountain Road, Framingham, Massachusetts
01701-9322, U.S.A., Tufts University School of Medicine, New England
Medical Center, Boston, Massachusetts 02111, U.S.A.
APStracts 3:0090L, 1996.
Cystic fibrosis (CF) airway epithelial cells exhibit defective cAMP
-mediated chloride (Cl-) secretion, abnormal hyperabsorption of sodium
(Na+), and aberrant fluid transport. Adenovirus-mediated transduction
of cystic fibrosis transmembrane conductance regulator (CFTR)
corrects these ion and fluid transport abnormalities in CF cells.
However, several challenges remain pertaining to the use of
adenovirus vectors for gene delivery, including the efficiency of
gene transfer and the host response to the vector. To improve the
efficacy of adenovirus-mediated gene transfer, we have constructed a
series of recombinant adenoviruses containing different CFTR
transcriptional units and we have evaluated their relative ability to
correct electrolyte and fluid transport in polarized CF airway
epithelial cells. The ability of the vectors to correct the CF Cl-
transport defects was greatest when the human cytomegalovirus (CMV)
promoter was used. The E1a and phosphoglycerate kinase (PGK)
promoters resulted in the greatest persistence of functional CFTR
expression. Efficacy of gene expression by recombinant adenoviruses
improved as the cells were treated with increasing multiplicities of
infection, as the duration of viral contact with the target cells was
lengthened, and when the virus concentration was increased.
Transduction of functional CFTR Cl- channel activity reversed the
abnormal Na+ hyperabsorption observed in CF cells in a dose-dependent
manner, suggesting that Na+ channel activity is down-regulated by
CFTR. Although efficient correction of both cAMP-mediated Cl-
transport and fluid secretion could be achieved readily with these
vectors, normalization of the Na+ absorption required vector
administration at high multiplicities of infection.
Received 18 December 1995; accepted in final form 22 May 1996.
APS Manuscript Number L371-5.
Article publication pending Am. J. Physiol. (Lung Cell. Mol.
Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 17 June 96