Generation of human induced pluripotent stem cells using non-synthetic mRNA

Area of Science:

• Stem Cell Biology
• Molecular Biology
• Gene Therapy

Background:

• Induced pluripotent stem cells (iPSCs) are crucial for regenerative medicine.
• Current methods for iPSC generation often involve viral vectors or complex chemical treatments.
• Developing safe, efficient, and accessible reprogramming methods is essential.

Purpose of the Study:

• To describe a novel mRNA transfection protocol for generating human iPSCs.
• To optimize mRNA capping and delivery for enhanced efficiency and reduced immunogenicity.
• To establish a fast, inexpensive, and non-viral method for iPSC generation.

Main Methods:

• Utilized a V. virus-derived capping enzyme for efficient mRNA synthesis with proper cap orientation.
• Employed a 2'-O-Methyltransferase enzyme to create a cap1 structure for higher translation efficiency.
• Used polyethylenimine as a superior polymeric transfection reagent.
• Cultured cells under low oxygen conditions to enhance colony formation.
• Confirmed pluripotency and differentiation potential via teratoma assay.

Main Results:

• Achieved 100% proper cap orientation in in vitro transcribed mRNA.
• Demonstrated high mRNA and protein expression levels (>48h) without triggering intracellular immune responses (hIFN-γ, hIFN-α release).
• Observed swift activation of pluripotency-associated genes in human fibroblasts.
• Facilitated colony formation under low oxygen conditions.
• Confirmed successful differentiation into all three germ layers via teratoma assay.

Conclusions:

• Non-synthetic mRNA reprogramming offers a promising avenue for safe human iPSC generation.
• The described method is fast, inexpensive, and avoids viral vectors.
• This protocol can make iPSC generation more accessible to researchers worldwide.