Synergistic Enhancement of Transient Expression by Dioleoyl-Melittin (DOM) and Polyethylenimine (PEI) in Mammalian Cells in Suspensionculture

Abstract

Dioleoyl-melittin, which is a conjugate of dioleoyl-phosphatidyl-ethanolamine-N-3-(2-pyridyldithio) propionate with the amphipatic peptide melittin Gly-Cys 1 represents a new class of peptide-based reagent for efficient transfection of mammalian cells. In this work we investigated the transfection efficiency of dioleoyl-melittin (DOM) combined with polyethylenimine (PEI) using HEK293(EBNA) cells grown in serum-free suspension cultures. Gene expression was monitored using the luciferase reporter gene and the human soluble TNF receptor p55 gene (TNFRp55) inserted into different vectors. Our data clearly show that DOM together with PEI exhibited synergistic enhancement for gene expression in EBNA cells. At the optimal DNA-DOM-PEI weight ratio the efficiency of transfection increases significantly compared to corresponding PEI and DOM transfection at low DNA concentration. In summary, our data show that dioleoyl-melittin and polyethylenimine act synergistically in transfecting 293(EBNA) cells grown in serum-free suspension culture.