title: Oligochitosan polyplexes as carriers for retinal gene delivery.
abstract: Non-viral gene therapy represents a promising approach for the treatment of retinal diseases. However, the lack of an efficient carrier hampers the implementation of this therapy. In this study, we evaluated low molecular weight ultrapure oligochitosans for the delivery of the pCMS-EGFP plasmid into the rat retina cells after subretinal and intravitreal administrations. Polyplexes were technologically characterized. Resulting polyplexes based on ultrapure oligochitosans were slightly spherical, protected the plasmid against enzymatic digestion, and their charge and size values ranged from 8 to 14 millivolts and from 150 to 69 nm respectively depending on the N/P ratio. In HEK-293 cultured cells, transfection efficiency significantly increased from 12% to 30% when pH decreased from 7.4 to 7.1 (data normalized to Lipofectamine™ 2000). However, no significant transfection was detected in ARPE-19 cultured cells. Subretinal administrations transfected mainly the pigmented cells of the retinal pigment epithelium and the light sensitive photoreceptor cells, whereas intravitreal injections transfected cells in the ganglion cell layer, blood vessels in the inner layers of the retina and photoreceptors. These results support the potential use of oligochitosans for delivering genetic material into retinal cells in vivo.
authors.affiliation: NanoBioCel Group, University of Basque Country, Vitoria, Spain.
authors.forename: G
authors.initials: G
authors.lastname: Puras
authors.forename: J
authors.initials: J
authors.lastname: Zarate
authors.forename: A
authors.initials: A
authors.lastname: Díaz-Tahoces
authors.forename: Marcelino
authors.initials: M
authors.lastname: Avilés-Trigueros
authors.forename: E
authors.initials: E
authors.lastname: Fernández
authors.forename: J L
authors.initials: JL
authors.lastname: Pedraz
mesh_terms: D000818:Animals; D002460:Cell Line; D002686:Chitin / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000737:chemistry; D048271:Chitosan; D004247:DNA / Q000008:administration & dosage* / Q000737:chemistry; D015316:Genetic Therapy / Q000379:methods; D005822:Genetic Vectors; D049452:Green Fluorescent Proteins / Q000737:chemistry / Q000235:genetics*; D057809:HEK293 Cells; D006801:Humans; D008297:Male; D009844:Oligosaccharides; D010957:Plasmids; D051381:Rats; D017207:Rats, Sprague-Dawley; D012160:Retina / Q000378:metabolism*
chemical_list: D009844:Oligosaccharides; C485184:enhanced green fluorescent protein; C493484:oligochitosan; D002686:Chitin; D049452:Green Fluorescent Proteins; D004247:DNA; D048271:Chitosan