The SP-C promoter facilitates alveolar type II epithelial cell-specific plasmid nuclear import and gene expression.
Although nonviral gene therapy has great potential for use in the lung, the relative lack of cell-specific targeting has limited its applications. We have developed a new approach for cell-specific targeting based on selective nuclear import of plasmids in nondividing cells. Using a microinjection and in situ hybridization approach, we tested several potential DNA sequences for the ability to mediate plasmid nuclear import in alveolar type II epithelial (ATII) cells. Of these, only a sequence within the human surfactant protein C (SP-C) promoter was able to mediate nuclear localization of plasmid DNA specifically in ATII cells but not in other cell types. We have mapped the minimal import sequence to the proximal 318 nucleotides of the promoter, and demonstrate that binding sites for nuclear factor I, thyroid transcriptional factor 1, and GATA-binding protein 6 and the proteins themselves are required for import activity. Using intratracheal delivery of DNA followed by electroporation, we demonstrate that the SP-C promoter sequence will enhance gene expression specifically in ATII cells in mouse lung. This represents a new activity for the SP-C promoter, and thus ATII cell-specific nuclear import of DNA may prove to be a safe and effective method for targeted and enhanced gene expression in ATII cells.
Degiulio
J V
JV
Division of Pulmonary and Critical Care Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
Kaufman
C D
CD
Dean
D A
DA
D021581:Active Transport, Cell Nucleus / Q000235:genetics / Q000276:immunology*; D056809:Alveolar Epithelial Cells / Q000166:cytology / Q000378:metabolism*; D000818:Animals; D001665:Binding Sites / Q000235:genetics; D018274:Electroporation; D050993:GATA6 Transcription Factor / Q000235:genetics; D005786:Gene Expression Regulation / Q000235:genetics*; D015316:Genetic Therapy / Q000379:methods*; D006801:Humans; D017403:In Situ Hybridization; D008168:Lung / Q000166:cytology / Q000378:metabolism; D051379:Mice; D051839:NFI Transcription Factors / Q000235:genetics; D009687:Nuclear Proteins / Q000235:genetics; D010957:Plasmids / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics*; D037721:Pulmonary Surfactant-Associated Protein C / Q000235:genetics*; D000074482:Thyroid Nuclear Factor 1; D014157:Transcription Factors / Q000235:genetics
D050993:GATA6 Transcription Factor; D051839:NFI Transcription Factors; D009687:Nuclear Proteins; D037721:Pulmonary Surfactant-Associated Protein C; D000074482:Thyroid Nuclear Factor 1; D014157:Transcription Factors