Mouse Pluripotent Stem Cell Differentiation Under Physiological Oxygen Reduces Residual Teratomas

Area of Science:

• Stem Cell Biology
• Developmental Biology
• Regenerative Medicine

Background:

• Residual pluripotent stem cells (PSCs) in differentiated cell populations pose a significant risk due to their tumorigenic potential.
• Tumor formation from residual PSCs is a major safety concern for cell-based therapies.
• There is a need for straightforward methods to mitigate PSC contamination.

Purpose of the Study:

• To investigate the effect of physiological oxygen partial pressure (pO2) on reducing residual PSCs in differentiated populations.
• To assess the impact of low pO2 culture on the tumorigenic potential of differentiated cell populations.

Main Methods:

• Culture of mouse PSCs (mPSCs) on a highly oxygen-permeable substrate to achieve physiological pO2.
• Differentiation and extended culture of mPSCs at controlled low pO2 levels.
• Quantification of pluripotency markers and assessment of tumor formation after implantation in immunocompromised mice.

Main Results:

• Low pO2 culture reduced pluripotency markers by up to four orders of magnitude.
• Combining low pO2 with cell sorting achieved a six-fold reduction in pluripotency markers.
• mPSCs differentiated at low pO2 exhibited reduced or slower tumor formation compared to those cultured at high pO2.

Conclusions:

• Culture at physiological low pO2 is an effective strategy to minimize residual PSCs.
• This method can significantly reduce the tumorigenic potential of differentiated cell populations.
• Low pO2 culture presents a simple and applicable approach for enhancing cell therapy safety protocols.