Enhanced in vivo airway gene transfer via transient modification of host barrier properties with a surface-active agent.

Effective adenoviral gene therapy requires efficient viral vector entry into epithelial cells. Injured airway epithelia display enhanced gene transfer, reflecting in part increased vector access to protected cell populations and/or protected basolateral membranes. We tested whether adenoviral gene transfer is enhanced by modification of the epithelial barrier in mouse nasal airways with a nonionic detergent (polidocanol, PDOC). In C57BL/6 mice, 1.6 x 10(9) PFU of Ad5CMV LacZ (AdLacZ) instilled into the right nostril produced negligible gene transfer to the nasal epithelium 2 days after dosing, but significant, dose-dependent increases in gene transfer were achieved by pretreatment with PDOC. Permeation of the electron-dense tracer lanthanum into the intercellular junctions of PDOC (0.1%)-treated murine nasal epithelium, but not into intercellular junctions of vehicle controls, is consistent with PDOC-mediated increases in tight junctional permeability. In CF(-/-) mice, significant gene expression was not detectable after exposure to Ad5CBCFTR alone (1.4 x 10(9) PFU in 20 microl; AdCFTR), but PDOC pretreatment prior to AdCFTR instillation produced functional expression of CFTR (measured as deltaPD) 5 days after instillation. Because the development and testing of lung gene therapy will principally occur in children and adults with airway disease, AdLacZ gene transfer with and without PDOC pretreatment was examined in infected nasal airways. Gene expression was significantly reduced in infected as compared with uninfected airways. We conclude that the use of adjuvant surface-active and/or membrane-perturbing agents, synthetic or naturally derived, may provide a novel approach to enhancing the efficiency of adenoviral gene transfer.

Intrathoracic silo for fetal diaphragmatic hernia: lung growth and slow reduction of abdominal viscera.

Correction of a left congenital diaphragmatic hernia in a human fetus with a large volume of liver in the chest requires reduction of liver and viscera into the abdomen. This can kink the ductus venosus and cause the death of the fetus. Therefore, we have repaired surgically created diaphragmatic hernias in fetal lambs by leaving viscera in the chest wrapped in a silastic chimney. With fetal growth there is a relative reduction of hernia volume over weeks, potentially avoiding kinking the ductus venosus. In four groups of lambs lung size and static respiratory system compliance at birth were compared. Lambs treated by this new technique (silo, n = 7) were compared with lambs that had undergone immediate complete correction with a flat silastic patch in the diaphragm plus an abdominal patch (patch, n = 8), with lambs with uncorrected hernias (n = 6), and with normals (n = 8). There was no significant difference between total lung weights (131 +/- 6 g v 157 +/- 13 g, mean +/- SEM, silo v patch) and lung displacement volumes (142 +/- 7 mL v 162 +/- 14 mL) in either surgically corrected group. Lungs from those corrected by silo were significantly heavier than those with uncorrected herniae (131 +/- 6 g v 56 +/- 5 g, P < .01), but were not as heavy as normal lungs (131 +/- 6 g v 257 +/- 16 g, P < .01).(ABSTRACT TRUNCATED AT 250 WORDS)