생분해성 고분자로 표면개질 된 아데노바이러스의 세포 내 도입효율과 향상된 항 종양 효과 평가

Abstract

Adenovirus (Ad) vectors as a delivery vehicle has shown great promise in cancer gene therapy but its immunogenic safety concerns and Coxsackie virus and Adenovirus Receptor (CAR) dependency have limited their use in virotherapy. To overcome these hurdles, biocompatible and bioreducable, non-viral vector delivery methods such as arginine grafted cationic polymers, have shown significant potential to deliver nucleic acids through a cell penetration peptide (CPP) effect. We utilized the advantages of both viral and non-viral vectors to develop an intelligent hybrid vector by coating an Ad with double arginine-grafted links to a polyethylene glycol (PEG)-Polyethyleneamine (PEI) backbone (Ad/PPSA nanocomplex). We characterized the particle size and zeta potential of Ad/PPSA in a polymer concentration-dependent manner and observed an increase in size and development of a cationic charge of the overall Ad/PPSA complex. Ad/PPSA also showed a marked increase in transduction efficiency in both CAR negative and positive cells compared with naked Ad. Competition assay results demonstrated Ad/PPSA to produce higher levels of transgene expression than naked Ad, and transduce independently to CAR. In addition, Ad/PPSA, through its selective cell-killing effects, was able to overcome the non-specificity of polymer only therapies. Furthermore, the oncolytic Ad/PPSA nanocomplex elicited a 2.24-fold greater antitumor efficacy than naked Ad supported by immunochemical staining confirmation of the accumulation of Ad E1As in tumors in the MCF7 human tumor xenograft model. Lastly, intravenous injection of Ad/PPSA significantly reduced the innate immune response in contrast with naked Ad, as evaluated by interleukin-6 cytokine release from serum collections. Thus, the increased antitumor effect and improved target to both CAR negative and positive cells of Ad/PPSA make it a promising tool for cancer gene therapy.