Bioreducible poly(urethane amine)s for robust nucleic acid transfection in stem cells

Area of Science:

• Biomaterials Science
• Gene Therapy
• Stem Cell Biology

Background:

• Developing effective non-viral gene delivery vectors for stem cells is crucial for regenerative medicine.
• Cationic polymers are promising but face challenges in achieving robust transfection and low toxicity.

Purpose of the Study:

• To synthesize and evaluate linear bioreducible poly(urethane amine)s (SPPUAs) as non-viral vectors for stem cell gene transfection.
• To assess the transfection efficiency and cytotoxicity of SPPUAs in various stem cell types, including human and animal models.

Main Methods:

• Synthesis of linear bioreducible poly(urethane amine)s (SPPUAs) with disulfide and protonable amino groups.
• In vitro gene transfection assays using green fluorescence protein (GFP) in human adipose-derived stem cells (hADSCs), human bone marrow stem cells (hBMSCs), and stem cells from rats, dogs, and monkeys.
• Evaluation of SPPUAs' ability to deliver small interfering RNA (siRNA) for gene silencing in hADSCs.
• Cytotoxicity assessments of SPPUAs on stem cells.

Main Results:

• Optimized SPPUA copolymers (SSBT) demonstrated high transfection efficiency, with SSBT10 achieving ~60% GFP+ hADSCs and SSBT30 achieving ~40% GFP+ hBMSCs.
• SPPUAs effectively transfected stem cells from various animal models (~40-70% GFP+ cells).
• SPPUAs exhibited superior transfection efficiency compared to branched polyethylenimine and Lipofectamine 2000, with low cytotoxicity.
• SSBT30 demonstrated efficient siRNA delivery for BCL2L2 or TRIB2 gene silencing in hADSCs.

Conclusions:

• Linear bioreducible poly(urethane amine)s (SPPUAs) represent a promising platform for efficient and safe gene delivery into diverse stem cell populations.
• SPPUAs offer a viable alternative to viral vectors and current non-viral methods for stem cell-based gene therapy and regenerative medicine applications.