title: Hydroxyl PAMAM dendrimer-based gene vectors for transgene delivery to human retinal pigment epithelial cells.
abstract: Ocular gene therapy holds promise for the treatment of numerous blinding disorders. Despite the significant progress in the field of viral and non-viral gene delivery to the eye, significant obstacles remain in the way of achieving high-level transgene expression without adverse effects. The retinal pigment epithelium (RPE) is involved in the pathogenesis of retinal diseases and is a key target for a number of gene-based therapeutics. In this study, we addressed the inherent drawbacks of non-viral gene vectors and combined different approaches to design an efficient and safe dendrimer-based gene-delivery platform for delivery to human RPE cells. We used hydroxyl-terminated polyamidoamine (PAMAM) dendrimers functionalized with various amounts of amine groups to achieve effective plasmid compaction. We further used triamcinolone acetonide (TA) as a nuclear localization enhancer for the dendrimer-gene complex and achieved significant improvement in cell uptake and transfection of hard-to-transfect human RPE cells. To improve colloidal stability, we further shielded the gene vector surface through incorporation of PEGylated dendrimer along with dendrimer-TA for DNA complexation. The resultant complexes showed improved stability while minimally affecting transgene delivery, thus improving the translational relevance of this platform.
authors.affiliation: Center for Nanomedicine at the Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA. krangar1@jhmi.edu.
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Mastorakos
authors.forename: Siva P
authors.initials: SP
authors.lastname: Kambhampati
authors.forename: Manoj K
authors.initials: MK
authors.lastname: Mishra
authors.forename: Tony
authors.initials: T
authors.lastname: Wu
authors.forename: Eric
authors.initials: E
authors.lastname: Song
authors.forename: Justin
authors.initials: J
authors.lastname: Hanes
authors.forename: Rangaramanujam M
authors.initials: RM
authors.lastname: Kannan
mesh_terms: D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D050091:Dendrimers / Q000138:chemical synthesis / Q000737:chemistry* / Q000633:toxicity; D004847:Epithelial Cells / Q000166:cytology / Q000378:metabolism; D005822:Genetic Vectors / Q000737:chemistry* / Q000378:metabolism / Q000633:toxicity; D006801:Humans; D008856:Microscopy, Fluorescence; D011073:Polyamines / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D012160:Retina / Q000166:cytology; D014162:Transfection; D014222:Triamcinolone Acetonide / Q000737:chemistry
chemical_list: D050091:Dendrimers; C104700:PAMAM Starburst; C531249:Poly(amidoamine); D011073:Polyamines; D011092:Polyethylene Glycols; D014222:Triamcinolone Acetonide