Vascular endothelium gene expression regulates blood-vessel wall interactio
ns, vascular permeability, smooth muscle cell growth and tone. The possibil
ity to introduce exogenous DNA or RNA sequences in endothelial cells repres
ents a novel therapeutic approach of vascular disease. The aim of the work
was to investigate the ability of endothelial cells to internalize and expr
ess exogenous DNA sequences. Human umbilical vein endothelial cells (HUVEC)
were transfected with either a 780 bp fluorescein-labeled DNA (FITC-DNA) o
r pEGFP-C1 plasmid encoding for a green fluorescent protein (GFP), using th
e cationic liposome DOTAP as transfection reagent. The transfected cell pop
ulation was passed through a FACScan apparatus and percentage of fluorescen
t cells was determined using a FACScan analysis programme. The SW620 tumor-
derived cell line was used as control. The percentage of FITC-DNA positive
cells was 66.0% for HUVEC and 45.0% for SW620 cells. On the contrary, the p
ercentage of GFP-positive cells was 13.8% and 43% for HUVEC and SW620, resp
ectively. By increasing the amount of DNA as well as the protocol of admini
stration the percentage of GFP-positive HUVEC was enhanced suggesting a rap
id degradation of DNA in the HUVEC cytoplasm.