The developmental potential of iPSCs is greatly influenced by reprogramming factor selection

Area of Science:

• Stem cell biology
• Epigenetics
• Genetics

Background:

• Induced pluripotent stem cells (iPSCs) are crucial for regenerative medicine.
• Current methods using Oct4, Sox2, Klf4, and Myc (OSKM) yield variable iPSC quality.
• High-quality iPSCs are essential for therapeutic applications.

Purpose of the Study:

• To identify reprogramming factor combinations that yield high-quality induced pluripotent stem cells.
• To compare the efficiency of SNEL versus OSKM in generating high-quality iPSCs.
• To investigate molecular differences between high- and low-quality iPSC lines.

Main Methods:

• Utilized tetraploid complementation assays in mice to assess iPSC quality.
• Ectopically expressed Sall4, Nanog, Esrrb, and Lin28 (SNEL) in mouse embryonic fibroblasts (MEFs).
• Compared SNEL-generated iPSCs with those generated by OSKM and other factor combinations.

Main Results:

• The SNEL factor combination generated high-quality iPSCs more efficiently than OSKM.
• Key epigenetic markers and global aneuploidy were comparable between high- and low-quality lines.
• Aberrant gene expression, trisomy 8, and abnormal H2A.X deposition distinguished low-quality iPSCs.

Conclusions:

• The choice of reprogramming factors is a critical determinant of iPSC quality.
• SNEL represents a more efficient combination for generating high-quality iPSCs.
• Specific molecular aberrations may serve as biomarkers for iPSC quality assessment.