Targeted decationized polyplexes for siRNA delivery.
The applicability of small interfering RNA (siRNA) in future therapies depends on the availability of safe and efficient carrier systems. Ideally, siRNA delivery requires a system that is stable in the circulation but upon specific uptake into target cells can rapidly release its cargo into the cytoplasm. Previously, we evaluated a novel generation of carrier systems ("decationized" polyplexes) for DNA delivery, and it was shown that folate targeted decationized polyplexes had an excellent safety profile and showed intracellular triggered release upon cell specific uptake. Targeted decationized polyplexes consist of a core of disulfide cross-linked poly(hydroxypropyl methacrylamide) (pHPMA) stably entrapping nucleic acids and a shell of poly(ethylene glycol) (PEG) decorated with folate molecules. In the present study, the applicability of folate targeted decationized polyplexes for siRNA delivery was investigated. This required optimization of the carrier system particularly regarding the cross-linking density of the core of the polyplexes. Stable and nanosized siRNA decationized polyplexes were successfully prepared by optimizing the cross-link density of their core. Upon incubation in human plasma, a significant portion of siRNA remained entrapped in the decationized polyplexes as determined by fluorescence correlation spectroscopy (FCS). When tested in a folate receptor overexpressing cell line stably expressing luciferase, Skov3-luc, sequence specific gene silencing was observed. As expected, neither interference on the intrinsic luciferase expression nor on the cell metabolic activity (determined by XTT) was induced by the free-polymer or the siRNA polyplexes. In conclusion, targeted decationized polyplexes are safe and stable carriers that interact with the targeted cells and rapidly disassemble upon cell entry making them promising siRNA delivery systems.
Department of Pharmaceutics, Utrecht Institute for Pharmaceutical Sciences, Utrecht University , 3584, CG Utrecht, The Netherlands.
Luís
L
Novo
Kaori M
KM
Takeda
Tamara
T
Petteta
George R
GR
Dakwar
Joep B
JB
van den Dikkenberg
Katrien
K
Remaut
Kevin
K
Braeckmans
Cornelus F
CF
van Nostrum
Enrico
E
Mastrobattista
Wim E
WE
Hennink
D001672:Biocompatible Materials / Q000737:chemistry; D045744:Cell Line, Tumor; D005492:Folic Acid / Q000737:chemistry; D020868:Gene Silencing; D018014:Gene Transfer Techniques; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008689:Methacrylates / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology; D009696:Nucleic Acids / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D034741:RNA, Small Interfering / Q000008:administration & dosage*; D013056:Spectrophotometry, Ultraviolet
D001672:Biocompatible Materials; D008689:Methacrylates; D009696:Nucleic Acids; D011108:Polymers; D034741:RNA, Small Interfering; D011092:Polyethylene Glycols; D005492:Folic Acid; C032802:hydroxypropyl methacrylate
biocompatibility; nanoparticle; polymer; siRNA delivery; targeting