title: Targeting type II and Clara cells for adenovirus-mediated gene transfer using the surfactant protein B promoter.
abstract: We examined the ability of the human surfactant protein B (SP-B) promoter to confer cell specificity of transgene expression in an adenoviral vector. Using similar replication-deficient adenoviruses (rAd), we compared lacZ reporter gene expression driven by the human SP-B promoter (rAd.SPBlacZ) with the ubiquitously expressed Rous sarcoma virus promoter (rAd.RSVlacZ). rAd.SPBlacZ expressed lacZ in H-441 and A549 lung epithelial cell lines and not in HeLa cells whereas rAd.RSVlacZ expressed in all three cell lines. In primary human fetal lung fibroblasts, beta-galactosidase activity from rAd.RSVlacZ transduction increased in a dose-dependent manner whereas activity from rAd.SPBlacZ remained low. In mixed cell cultures prepared from human fetal lung explants that contained fibroblasts and type II cells, X-Gal staining localized rAd.SPBlacZ expression to only type II cells whereas rAd.RSVlacZ expressed in both cell types. In 24-wk gestation human fetal tissue explants infected ex vivo, the RSV promoter directed lacZ expression in lung, trachea, heart, liver, and esophagus, whereas with the SP-B promoter lacZ was expressed only in lung, specifically in air space-lining cells. This specificity was maintained in vivo. lacZ expression was undetectable in lung and other tissues after intravenous administration of rAd.SPBlacZ whereas rAd.RSV-lacZ expressed primarily in liver. After intratracheal instillation of rAd.SPBlacZ into mice, X-Gal staining localized expression to type II and Clara cells. In contrast, rAd.RSVlacZ expressed in all pulmonary epithelial cell types. Our results indicate that the SP-B promoter may be useful in targeting type II and Clara cells for gene therapy of conditions such as inherited deficiency of SP-B.
authors.affiliation: Department of Pediatrics, University of Pennsylvania, and Children's Hospital of Philadelphia, 19104, USA.
authors.forename: M S
authors.initials: MS
authors.lastname: Strayer
authors.forename: S H
authors.initials: SH
authors.lastname: Guttentag
authors.forename: P L
authors.initials: PL
authors.lastname: Ballard
mesh_terms: D000230:Adenocarcinoma; D000256:Adenoviridae / Q000235:genetics*; D000818:Animals; D015152:Blotting, Northern; D015153:Blotting, Western; D005260:Female; D015870:Gene Expression; D018390:Gene Targeting; D018014:Gene Transfer Techniques; D006367:HeLa Cells; D006801:Humans; D007150:Immunohistochemistry; D008168:Lung / Q000166:cytology* / Q000378:metabolism; D008175:Lung Neoplasms; D051379:Mice; D010957:Plasmids / Q000235:genetics; D011401:Promoter Regions, Genetic; D011510:Proteolipids / Q000032:analysis / Q000235:genetics*; D011663:Pulmonary Surfactants / Q000032:analysis / Q000235:genetics*; D011994:Recombinant Proteins; D014407:Tumor Cells, Cultured; D001616:beta-Galactosidase / Q000032:analysis
chemical_list: D011510:Proteolipids; D011663:Pulmonary Surfactants; D011994:Recombinant Proteins; D001616:beta-Galactosidase