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Updated: May 16, 2026
06:48
Limbal Approach-Subretinal Injection of Viral Vectors for Gene Therapy in Mice Retinal Pigment Epithelium
Published on: August 7, 2015
Oligochitosan polyplexes as carriers for retinal gene delivery
G Puras1, J Zarate, A Díaz-Tahoces
1NanoBioCel Group, University of Basque Country, Vitoria, Spain.
Summary
Ultrapure oligochitosans show potential as non-viral gene carriers for retinal diseases. These oligochitosan polyplexes efficiently delivered genetic material into rat retinal cells via subretinal and intravitreal injections.
Area of Science:
- Ophthalmology
- Gene Therapy
- Biomaterials Science
Background:
- Non-viral gene therapy offers a promising avenue for treating retinal diseases.
- Efficient and safe gene delivery vectors are crucial for the clinical application of retinal gene therapy.
- Current limitations in gene delivery carriers hinder the progress of non-viral gene therapy for ocular conditions.
Purpose of the Study:
- To evaluate ultrapure oligochitosans as non-viral carriers for gene delivery into rat retinal cells.
- To characterize the physicochemical properties of oligochitosan-plasmid complexes (polyplexes).
- To assess the transfection efficiency and cell-specific delivery of oligochitosan polyplexes following different administration routes.
Main Methods:
- Preparation and technological characterization of oligochitosan-plasmid polyplexes.
- Assessment of plasmid protection against enzymatic digestion.
- In vitro transfection studies in HEK-293 and ARPE-19 cell lines at varying pH conditions.
- In vivo gene delivery evaluation in rat retina following subretinal and intravitreal injections.
Main Results:
- Oligochitosan polyplexes were spherical, protected plasmid DNA, and exhibited size and charge dependent on the N/P ratio.
- Transfection efficiency in HEK-293 cells increased significantly with decreasing pH (7.4 to 7.1), outperforming Lipofectamine™ 2000 at pH 7.1.
- Subretinal injection targeted retinal pigment epithelium and photoreceptor cells; intravitreal injection targeted ganglion cells, retinal vasculature, and photoreceptors.
Conclusions:
- Ultrapure oligochitosans are effective non-viral vectors for gene delivery to various retinal cell types in vivo.
- Oligochitosan polyplexes demonstrate potential for developing novel gene therapy strategies for retinal diseases.
- The pH-dependent transfection efficiency suggests optimization opportunities for oligochitosan-based gene delivery systems.
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