ORMOPLEXEs for gene therapy: In vitro and in vivo assays

Gene therapy stays on the cutting edge of biomedical research, being the design of the optimal gene delivery vector one of the key requests. Silica-based nanoparticles (NPs) have emerged as promising non-viral gene delivery vector, due to their high biocompatibility, nontoxicity, non-immunogenicity, biodegradability and enormous bioconjugation versatility. In this work a sol-gel methodology for the synthesis of amino-functionalized silica NPs (NH2-ORMOSIL NPs) was optimized, and NPs were characterized by TEM and FTIR. In a first step NH2-ORMOSIL NPs were bioconjugated with a plasmid DNA, pVAX1-GFP, assembling an ORMOPLEXE, confirmed by agarose gel electrophoresis. In a second step, in vitro studies have been performed with cultured CHO cells, where ORMOPLEXEs transfection was proved by CLSM. In vivo transfection efficiency and bio-distribution were performed in Zebrafish (Danio rerio) embryos, assessed by FM. Finally, NPs ecotoxicity was studied in zebrafish embryos by following the mortality and developmental endpoints.