Comparative analysis of endoderm formation efficiency between mouse ES cells and iPS cells

Area of Science:

• Stem cell biology
• Developmental biology
• Regenerative medicine

Background:

• Definitive endoderm (DE) derived from stem cells can differentiate into hepatocytes, offering potential for liver disease treatment.
• While embryonic stem cells (ESCs) are well-studied for hepatocyte induction, the behavior of induced pluripotent stem cells (iPSCs) in endoderm differentiation requires further investigation.
• Establishing efficient iPSC-derived DE induction is crucial for advancing cell-based therapies for liver conditions.

Purpose of the Study:

• To establish an efficient method for inducing definitive endoderm (DE) from induced pluripotent stem cells (iPSCs).
• To comparatively analyze the efficacy of endoderm formation from mouse iPSCs versus mouse embryonic stem cells (ESCs).
• To investigate the efficiency of serum-free medium in DE differentiation from iPSCs.

Main Methods:

• Mouse ESCs and iPSCs were cultured to form embryoid bodies (EBs) over 2 or 5 days.
• Definitive endoderm (DE) induction was performed using activin A and basic fibroblast growth factor (bFGF).
• Gene expression (Sox17, Foxa2, Cxcr4) was analyzed via RT-PCR and real-time PCR; cellular proliferation was assessed using MTS assays.

Main Results:

• iPSCs demonstrated parallel mRNA expression to ESCs during EB differentiation.
• ESCs showed higher expression of Sox17 and Foxa2 in DE, while iPSCs exhibited higher Cxcr4 expression.
• Serum-free medium significantly enhanced cellular proliferation during EB formation and DE induction in iPSCs.

Conclusions:

• A 5-day EB formation followed by DE induction with activin A and bFGF in serum-free medium is an appropriate protocol for iPSCs.
• This optimized protocol represents a significant advancement for generating hepatocytes from iPSCs.
• The findings support the development of cell therapies for liver diseases using iPSC-derived hepatocytes.