Gene delivery to the lung using protein/polyethylenimine/plasmid complexes.

Area of Science:

• Biotechnology
• Molecular Biology
• Pulmonology

Background:

• Gene therapy holds significant potential for treating lung diseases, including cancer and genetic disorders.
• Effective and safe gene delivery systems are crucial for realizing this potential.
• Polyethylenimine (PEI) is a known DNA-binding polymer used in gene delivery, but its application in lung tissue requires optimization.

Purpose of the Study:

• To develop a novel, non-toxic intravenous method for efficient gene delivery specifically to lung tissue.
• To evaluate the efficacy and safety of using polyethylenimine in combination with albumin for plasmid delivery to the lungs.
• To assess the gene expression levels and durability following this novel delivery method.

Main Methods:

• A new intravenous delivery method was established using low, non-toxic doses of polyethylenimine (PEI) complexed with plasmid DNA and albumin.
• Luciferase reporter gene was used to quantify gene expression in lung tissues following administration.
• Gene expression was analyzed at different time points after single and multiple injections.

Main Results:

• Highly efficient gene expression was observed in lung interstitial and endothelial cells with minimal plasmid amounts (≤1 µg).
• Optimal gene expression levels were achieved with lower plasmid quantities, with higher amounts reducing relative expression.
• Maximal gene expression occurred 24-48 hours post-injection, with sustained expression over 20 days during multiple administrations without inhibition.

Conclusions:

• This novel PEI-albumin-based intravenous gene delivery method enables efficient and safe gene expression in lung tissues.
• The method is effective even with small plasmid doses and demonstrates durability over repeated administrations.
• This approach offers a promising strategy for therapeutic gene delivery in diseases requiring recurrent treatment.