Fetal gene transfer by transuterine injection of cationic liposome-DNA complexes

In utero injection of cationic liposome-DNA complexes (CLDCs) containing ch loramphenicol acetyltransferase, beta-galactosidase (beta-gal), or human gr anulocyte colony-stimulating factor (hG-CSF) expression plasmids produced h igh-level gene expression in fetal rats. Tissues adjacent to the injection site exhibited the highest levels of gene expression. Chloramphenicol acety ltransferase expression persisted for at least 14 days and was reexpressed following postnatal reinjection of CLDCs. Intraperitoneal administration of the hG-CSF gene produced high serum hG-CSF levels. X-gal staining demonstr ated widespread beta-gal expression in multiple fetal tissues and cell type s. No toxic or inflammatory responses were observed, nor was there evidence of fetal-maternal or maternal-fetal gene transfer, suggesting that CLDCs m ay provide a useful alternative to viral vectors for in utero gene transfer .