The light-control feature allows the researchers to control the release site and timing with pinpoint accuracy. That feature alone means that the recipient can be dosed more broadly with reasonable safety but by the use of light activation, only the target area is exposed to the intended gene therapy. Although the initial research targets cancerous tumours, perhaps the most obvious applications by virtue of the optical access allowed to most of its anatomy, are ocular treatments, perhaps not only gene therapy but other treatments including for AMD, diabetes, and the glaucomas. The method has been described as non-invasive gene therapy.
The Trojan horseEssentially, the nano carrier is a modified, three-layered lysosome consisting of a modified, hydrophilic ‘shell’ to avoid interactions with biological entities en-route to its target, especially blood components, an intermediate layer loaded with photosensitisers to allow light activation (unloading of the therapeutic entity), and the therapeutic DNA mother-lode as the core.
Irradiating the photosensitiser layer with light disrupts the lysomal mbrane thereby spilling the DNA locally on-dand. Lysosomes are spherical mbrane-bound cell organelles found in most animal cells except erythrocytes. Normally, they are loaded with enzymes capable of the controlled breakdown of most biomolecules including proteins, nucleic acids, carbohydrates, lipids, and cellular debris (after the Wikipedia entry for Lysosome)
Early results show that the method is some 100x more efficient than other techniques. No ophthalmic applications for the technology have been canvassed yet but the research is still in its early phase. Proof-of-concept studies have been completed successfully. Could a needle-less anti-VEGF AMD treatment with simple, local, light activation be a possibility? Many AMD patients and their ophthalmologists are probably hoping so.