Widespread and efficient marker gene expression in the airway epithelia of fetal sheep after minimally invasive tracheal application of recombinant adenovirus in utero.
Cystic fibrosis is a common lethal genetic disease caused by functional absence of the cystic fibrosis transmembrane conductance regulator (CFTR). Although a candidate disease for in utero gene therapy, demonstration of potentially therapeutic levels of transgene expression in the fetal airways after minimally invasive gene delivery is a mandatory prerequisite before application of this approach in humans can be considered. We report here on the delivery of a beta-galactosidase expressing adenovirus directly to the airways of fetal sheep in utero using ultrasound-guided percutaneous injection of the trachea in the fetal chest. Injection of adenoviral particles to the fetal airways was not associated with mortality and resulted in low-level expression in the peripheral airways. However, complexation of the virus with DEAE dextran, which confers a positive charge to the virus, and pretreatment of the airways with Na-caprate, which opens tight junctions, increased transgene expression, and a combination of these two enhancers resulted in widespread and efficient gene transfer of the fetal trachea and bronchial tree. Using a percutaneous ultrasound-guided injection technique, we have clearly demonstrated proof of principle for substantial transgene delivery to the fetal airways providing levels of gene expression that could be relevant for a therapeutic application of CFTR expressing vectors.
Peebles
D
D
Department of Obstetrics and Gynaecology, Royal Free and University College Medical School, London, UK.
Gregory
L G
LG
David
A
A
Themis
M
M
Waddington
S N
SN
Knapton
H J
HJ
Miah
M
M
Cook
T
T
Lawrence
L
L
Nivsarkar
M
M
Rodeck
C
C
Coutelle
C
C
D000256:Adenoviridae / Q000235:genetics*; D000818:Animals; D003550:Cystic Fibrosis / Q000628:therapy; D005260:Female; D005332:Fetoscopy / Q000379:methods*; D015870:Gene Expression; D015316:Genetic Therapy / Q000379:methods*; D005822:Genetic Vectors / Q000008:administration & dosage*; D007271:Injections, Intradermal; D023421:Models, Animal; D012756:Sheep; D014132:Trachea / Q000196:embryology / Q000378:metabolism*; D001616:beta-Galactosidase / Q000235:genetics
D001616:beta-Galactosidase