Inhalable Gene Therapy and the Lung Surfactant Problem

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Respiratory Medicine

Background:

• Intravenous lipid nanoparticles (LNPs) primarily target pulmonary endothelium, not diseased lung tissues.
• Inhaled delivery offers direct access to airways and alveolar epithelium but faces challenges.
• Current LNPs may fail to transfect alveolar epithelial cells due to lung surfactant (LS) interactions.

Purpose of the Study:

• To investigate the barrier posed by lung surfactant (LS) to inhaled RNA-carrying lipid nanoparticles (LNPs).
• To propose a new design strategy for inhalable LNPs that overcomes LS interactions.
• To enable efficient RNA-LNP delivery to target lung cells for treating respiratory diseases.

Main Methods:

• Investigating LNP-lung surfactant interactions.
• Screening LNP designs for LS penetration.
• Optimizing LNP formulations for cell uptake and endosomal escape.

Main Results:

• Lung surfactant (LS) is a significant barrier to LNP transfection in alveolar epithelial cells.
• Inspiration from biological agents and nanoparticles can guide LNP design.
• A multi-step screening process focusing on LS penetration, cell uptake, and endosomal release is proposed.

Conclusions:

• Current LNP delivery methods for lung diseases are suboptimal.
• Overcoming lung surfactant barriers is crucial for effective inhaled RNA-LNP therapy.
• A novel LNP design approach focusing on LS penetration can improve RNA delivery to lung epithelia.