Bioreducible dextran-polyethylenimine conjugates regulate transgene expression distribution in vivo

Area of Science:

• Biomaterials Science
• Gene Therapy
• Nanotechnology

Background:

• Non-viral vectors are crucial for safe gene delivery.
• Developing efficient and targeted gene delivery systems remains a challenge.
• Dextran-based conjugates offer potential for improved vector properties.

Purpose of the Study:

• To design and synthesize dextran-linear polyethylenimine (Dex-SS-LPEI) conjugates.
• To evaluate their efficacy as non-viral vectors for intravenous gene delivery into tumors.
• To investigate the role of dextran in modulating gene delivery and transfection efficiency.

Main Methods:

• Synthesis of Dex-SS-LPEI conjugates with varying molecular weights.
• Characterization of polyplex formation, size, and stability.
• In vitro transfection studies in various cell lines.
• In vivo gene delivery studies in tumor-bearing mice.

Main Results:

• Dex-SS-LPEI conjugates efficiently condensed DNA into nanosized polyplexes with good colloidal stability.
• In vitro studies showed efficient gene transfection, with optimal results for 5 kDa dextran and 5 kDa LPEI.
• In vivo studies demonstrated comparable or enhanced tumor transgene expression with reduced lung expression compared to control LPEI.
• Low in vitro cytotoxicity and no observed mortality in vivo.

Conclusions:

• Dextran plays a critical role in the in vivo gene delivery performance of Dex-SS-LPEI conjugates.
• Dex-SS-LPEI conjugates are safe and effective non-viral vectors for tumor-targeted gene delivery.
• These conjugates show significant potential for application in cancer gene therapy.