Use of nanoparticles in the treatment of age-related macular degeneration, glaucoma, and other degenerative retinal diseases

Nanotechnology provides an important new set of tools for the diagnosis and treatment of ocular diseases, a concept that has been reviewed previously.^1-4 Nanoparticles include colloidal carrier systems that can improve the efficacy of drug delivery by overcoming diffusion barriers, permitting reduced dosing (through more efficient tissue targeting) and sustained delivery. Viruses also can be considered a type of nanoparticle. Nanoparticle biodistribution is affected by particle size, shape, and surface properties.⁵ Particle size, for example, influences whether the particle is internalized through phagocytosis, caveolin-mediated endo- cytosis, or clathrin-mediated endocytosis, which in turn results in exposure of the nanoparticle to different intracellular environments.^6-8 Trans-activating tran- scriptional activator peptide favors macropmocytosis. Compacted polylysine DNA nanopartieles are taken into cells and transported directly to the nucleus by the cell surface receptor nucleolin.⁹.