Ability of plasmid DNA complexed with histidinylated lPEI and lPEI to cross in vitro lung and muscle vascular endothelial barriers

Abstract

DNA complexes made with cationic polymers (polyplexes) developed as nonviral vectors for gene therapy must be enabled to cross through vascular endothelium to transfect underlying tissues upon their administration in the blood circulation. Here, we evaluated the transendothelial passage (TEP) of DNA complexes made with histidinylated linear polyethylenimine (His-lPEI) or linear polyethylenimine (lPEI). In vitro studies were performed by using established transwell lung and skeletal muscle vascular endothelial barriers. The models were composed of a monolayer of human lung microvascular endothelial (HMVEC-L) cells and mouse cardiac endothelial (MCEC) cells formed on a PET insert and immortalized human tracheal epithelial (ΣCFTE29o-) cells and mouse myoblasts (C2C12) as target cells cultured in the lower chamber, respectively. When the vascular endothelium monolayer was established and characterized, the transfection efficiency of target (ΣCFTE29o- and C2C12) cells with plasmid DNA encoding luciferase was used to evaluate TEP of polyplexes. The luciferase activities with His-lPEI and lPEI polyplexes compared to those obtained in the absence of endothelial cell monolayer were 6.5% and 4.3% into ΣCFTE29o- cells, and 18.5% and 0.23% into C2C12 cells, respectively. The estimated rate for His-lPEI polyplexes was 0.135 μg/cm(2).h and 0.385 μg/cm(2).h through the HMVEC-L and MCEC monolayers, respectively. These results indicate that His-lPEI polyplexes can pass through the lung and skeletal muscle vascular endothelium and can transfect underlying cells.

Keywords: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide; 30μg/ml gentamicin and 15ng/ml amphotericin; 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid; BCA; C2C12; Cationic polymer; DNA transfection; DTT; EBM-2; EC; EDTA; FBS; FITC; GA-1000; HEPES; HMVEC-L; His-lPEI; IL-1β; MCEC; MTT; Non-viral vector; PBS; PET; Polyplexes; R(3)-IGF-1; RLU; TEER; TEP; TNF-α; Vascular endothelium; ZO-1; Zonula Occludens-1; bicinchoninic acid; dithiothreitol; endothelial basal medium-2; endothelial cells; ethylenediaminetetraacetic acid; fluoresceinyl phenylthiocarbamyl residue; foetal bovine serum; hEGF; hFGF-B; histidinylated linear polyethylenimine; human epidermal growth factor; human fibroblast growth factor-basic; human lung microvascular endothelial cells; human recombinant insulin-like growth factor; immortalized human tracheal epithelial cells; interleukin 1 β; lPEI; linear polyethylenimine; mouse cardiac endothelial cells; mouse myoblasts; pDNA; phosphate buffer saline; plasmid DNA; polyethylene terephtalate; relative light unit; transendothelial electrical resistance; transendothelial passage; tumour necrosis factor-alpha; vEGF; vascular endothelial growth factor; ΣCFTE29o-.