Comb-shaped polymer grafted with REDV peptide, PEG and PEI as targeting gene carrier for selective transfection of human endothelial cells.

If plasmid complexes prepared from targeting carriers have endothelial cell selectivity and high transfection efficiency, they can specifically enhance rapid endothelialization by delivering the corresponding gene plasmids. A high content of functional groups in the carriers benefits high selectivity efficiency. Herein, we have synthesized a comb-shaped polymer bearing several Arg-Glu-Asp-Val (REDV) peptides and poly(ethylene glycol) as a pEGFP-ZNF580 gene carrier with cell-type recognition of human endothelial cells. An amphiphilic block copolymer of poly(2-hydroxyethyl methacrylate)-block-poly(ε-caprolactone)-graft-poly(ethylene glycol)-graft-poly(ethyleneimine) conjugated with REDV peptide (PHEMA-b-PCL-g-PEG-g-PEI-REDV) is synthesized, and nanoparticles of it are prepared by polymer self-assembly. This polycationic PHEMA-b-PCL-g-PEG-g-PEI-REDV carrier effectively condenses pEGFP-ZNF580 plasmid to form REDV-targeted complexes and protects pEGFP-ZNF580 integrity from enzymatic hydrolysis. These REDV-targeted complexes exhibit low cytotoxicity but high transfection efficiency to EA.hy926 cells compared with non-targeted complexes (PHEMA-b-PCL-g-PEG-g-PEI/pEGFP-ZNF580) as demonstrated by MTT assay, fluorescence-activated cell sorting analysis and fluorescence analysis. Furthermore, the relative protein level of endothelial cells transfected by REDV-targeted complexes is higher than that by non-targeted complexes. Therefore, REDV-bearing carriers may have potential as effective and targeting transfer carriers for pEGFP-ZNF580 plasmid, and their complexes can be used in the endothelialization of artificial vascular grafts.