Light-directed gene delivery by photochemical internalisation.

Area of Science:

• Biotechnology
• Molecular Biology
• Gene Therapy

Background:

• Gene therapy faces challenges with endosomal entrapment of vectors, hindering efficient gene delivery.
• Non-viral vectors, in particular, struggle with endosomal escape, limiting their therapeutic potential.
• Photochemical internalisation (PCI) offers a novel solution to overcome these delivery barriers.

Purpose of the Study:

• To review the novel photochemical internalisation (PCI) technology for light-directed transgene delivery.
• To discuss the mechanism of PCI, involving photosensitisers and light activation for endosomal release.
• To explore the application and efficacy of PCI with both viral and non-viral gene vectors.

Main Methods:

• PCI utilizes photosensitisers localized in endocytic vesicle membranes.
• Activation of photosensitisers by light induces vesicle rupture, liberating entrapped vectors.
• Released transgenes are then available for nuclear transfer, transcription, and translation.

Main Results:

• PCI significantly improves gene transfer efficiency in vitro for non-viral vectors.
• Surprisingly, PCI also enhances gene delivery mediated by viral vectors like adenoviruses and adeno-associated viruses.
• Gene expression is localized to illuminated regions, allowing for site-specific gene delivery.

Conclusions:

• Photochemical internalisation (PCI) is a promising technology for overcoming endosomal barriers in gene therapy.
• PCI demonstrates broad applicability, enhancing gene transfer for diverse vector types.
• The light-dependent nature of PCI opens possibilities for precise, site-specific therapeutic gene delivery.