Evaluation of polyplexes as gene transfer agents

Non-viral transfection systems based on the complexes of DNA and polycation s ('polyplexes') were evaluated with respect to their effectiveness, toxici ty and cell type dependence in a variety of in vitro models. The panel of p olycations examined included branched and linear polyethyleneimines, poly[N -ethyl-4-vinyl pyridinium bromide], polyamidoamine dendrimer (Superfect (TM )), poly(propyleneimine) dendrimer (Astramol (TM)) and a conjugate of Pluro nic (R) P123 and polyethyleneimine (P123-g-PEI(2K)), having a graft-block c opolymer architecture. Using a panel of cell lines the linear polyethylenei mine ExGen (TM) 500, Superfect (TM), branched polyethyleneimine 25 kDa, and P123-g-PEI(2K) were determined as systems displaying highest transfection activity while exhibiting relatively low cytotoxicity. These systems had ac tivity higher than or comparable to lipid transfection reagents (Lipofectin (R), LipofectAMINE (TM), CeLLFECTIN (R) and DMRIE-C) but did not reveal se rum dependence and were less toxic than the lipids. Overall, this: study de monstrates good potential of structurally diverse polyplex systems as trans fection reagents with relatively low cytotoxicity. (C) 2001 Elsevier Scienc e B.V. All rights reserved.