Skeletal Muscle Stem Cells from PSC-Derived Teratomas Have Functional Regenerative Capacity

Area of Science:

• Regenerative Medicine
• Stem Cell Biology
• Muscle Biology

Background:

• Deriving functional skeletal muscle stem cells from pluripotent cells without genetic modification is challenging.
• Existing methods often require genetic manipulation, limiting their therapeutic potential.

Purpose of the Study:

• To investigate teratomas as a source of functional skeletal muscle stem cells.
• To evaluate the regenerative capacity of teratoma-derived myogenic progenitors in vivo.

Main Methods:

• Formation of teratomas in adult skeletal muscle.
• Isolation and purification of myogenic progenitors (α7-Integrin+, VCAM-1+) via Fluorescence-Activated Cell Sorting (FACS).
• Transplantation of teratoma-derived progenitors into diseased muscles of mice.

Main Results:

• Teratomas differentiate in vivo to yield abundant myogenic progenitors.
• Transplanted progenitors show high engraftment, regenerating up to 80% of muscle volume with as few as 40,000 cells.
• Regenerated muscle fibers are innervated, express adult myosins, and improve muscle function.
• Progenitors contribute to the quiescent PAX7+ muscle stem cell pool, ensuring long-term regeneration and response to injury.

Conclusions:

• Teratomas provide a rich and accessible source of potent, transplantable skeletal muscle stem cells.
• Teratoma-derived myogenic progenitors facilitate efficient muscle regeneration and long-term stem cell maintenance.
• These findings offer a novel, non-genetic approach for skeletal muscle repair and regenerative medicine.