Potent Gene Silencing In Vitro at Physiological pH Using ChitosanTI Potent Gene Silencing In Vitro at Physiological pH Using Chitosan Polymers

摘要

Among non-viral cationic polymers, biodegradable chitosan has during the last decade become an attractive carrier for small interference RNA (siRNA) delivery. Currently, degradation of macromolecules in the lysosomes is assumed to be a major barrier for effective siRNA transfection. Hence, transfection protocols are focused toward endosomal release mechanisms. In this work, we have tested 3 novel chitosan polymers and their siRNA delivery properties in vitro. To obtain efficient gene silencing of our model gene, S100A4, various transfection parameters were investigated, such as pH, nitrogen/phosphate ratio, photochemical internalization (PCI), media for complex formation, and cell lines. Our results showed that 2 linear chitosan polymers demonstrated excellent siRNA gene silencing, better than Lipofectamine 2000. The silencing effect was achieved without PCI treatment, under physiological pH, and with no observable reduction in cell viability.