title: Exogenous surfactant enhances the delivery of recombinant adenoviral vectors to the lung.
abstract: Somatic gene therapy for pulmonary diseases must be accomplished in vivo, requiring the spread of a gene transfer vector across a vast expanse of respiratory epithelium. Surfactant, a naturally occurring protein and lipid mixture used to treat the respiratory distress syndrome of prematurity, disperses rapidly and evenly throughout the lung. We employed exogenous bovine surfactant (Survanta beractant) as a carrier vehicle for pulmonary delivery of a recombinant adenovirus expressing beta-galactosidase (beta-Gal). Rats treated with an adenovirus-beractant mixture demonstrated more uniform lobar distribution of transgene expression than rats treated with the same amount of virus in saline. Tissue homogenates were examined for quantitative beta-Gal expression by reaction with o-nitrophenol beta-n-galactopyranoside (ONPG). The degree of beta-Gal activity was affected by both the volume and type of carrier used to deliver the virus. At low volumes (0.5 ml, 1.3 ml/kg), beractant-treated animals demonstrated significantly greater pulmonary beta-Gal activity than saline-treated animals (p < 0.002) and untreated controls. At high volume (1.2 ml, 4 ml/kg), average beta-Gal activity was similar between groups treated with beractant or saline, but was more variable within the saline treated group. Higher volumes of delivery medium were associated with increased levels of beta-Gal expression regardless of the carrier used. Survanta was well tolerated by the animals and did not affect the duration of transgene expression. Exogenous beractant provides a useful medium for delivering recombinant adenoviruses to the lung when diffuse distribution of transgene expression is desired.
authors.affiliation: Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA.
authors.forename: J P
authors.initials: JP
authors.lastname: Katkin
authors.forename: R C
authors.initials: RC
authors.lastname: Husser
authors.forename: C
authors.initials: C
authors.lastname: Langston
authors.forename: S E
authors.initials: SE
authors.lastname: Welty
mesh_terms: D000256:Adenoviridae / Q000235:genetics*; D000818:Animals; D001688:Biological Products; D004305:Dose-Response Relationship, Drug; D004338:Drug Combinations; D005260:Female; D015967:Gene Expression Regulation, Viral; D015316:Genetic Therapy / Q000379:methods; D005822:Genetic Vectors / Q000008:administration & dosage* / Q000235:genetics* / Q000494:pharmacology; D006801:Humans; D008168:Lung / Q000187:drug effects / Q000378:metabolism* / Q000821:virology; D011663:Pulmonary Surfactants / Q000008:administration & dosage / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D019076:Transgenes; D001616:beta-Galactosidase / Q000096:biosynthesis / Q000235:genetics
chemical_list: D001688:Biological Products; D004338:Drug Combinations; D011663:Pulmonary Surfactants; D011994:Recombinant Proteins; D001616:beta-Galactosidase; C072197:beractant