Three-Step Method For Universal Enrichment, Expansion, And Maturation Of Skeletal Muscle Cells Derived From Human Pluripotent Stem Cells

Summary

UCLA researchers have developed a novel method for enriching, expanding, and maturing populations of skeletal muscle progenitor cells (SMPCs) from human pluripotent stem cells (hPSCs).

Background

Skeletal muscle is one of the only organ systems endowed with an endogenous stem cell, the satellite cell (SC). However, the events controlling the timing and specification of SCs and early progenitors during human myogenesis have remained poorly defined. There is a need for a method to identify these early developmental cells prior to generating equivalent SMPCs from hPSCs with robust in vitro myogenic ability and in vivo engraftment potential.

Innovation

• Method for universal enrichment, expansion, and maturation of skeletal muscle cells derived from human pluripotent stem cells 
• RNA sequencing to perform the first-ever myogenic profile of different stages of human fetal and hPSC derived muscle 
• Identified that NGFR and ERBB3 are expressed by PAX7+ human fetal SCs

Applications

• Generating skeletal muscle from hPSCs using an integrated three-step enrichment, expansion, and maturation procedure 
• Directed differentiation protocol to improve myogenic activity in vitro and in vivo 
• Regenerative 
• Approaches for Duchenne’s muscular dystrophy 
• Applicable to multiple protocols and disease lines (e.g. human neuromuscular diseases, muscular dystrophy, metabolic and mitochondrial disease)

Advantages

This method enables:

• Development of human neuromuscular diseases, muscular dystrophy, metabolic and mitochondrial disease-based models that require functional myofibers 
• Improved understanding of human muscle development, maturation, and aging 
• The ability to generate adult-like skeletal muscle and/or skeletal muscle progenitor cells or satellite cells for autologous transplantation therapies 
• A delivery system (the corrected skeletal muscle stem cells) for delivery of gene edited cells (i.e. CRISPR/Cas9 corrected muscle stem cells) 
• Myofiber derived niche in situ to support and/or target PAX7+ cells ex vivo 
• The ability to develop co-culture and 3-dimensional models with functional human skeletal muscle to study disease and basic biology 
• Inhibition of TGF improves hPSC muscle maturation in the following ways: (i) Improved myogenic fusion in vitro and in vivo; (ii) Activation of adult myosin isoforms; (iii) Organized sarcomeres as measured by electron microscopy; (iv) Increased expression of transcription factors that regulate skeletal muscle maturation
• Significant engraftment in vivo with potential for systemic delivery of stem cells to muscles

State Of Development

The method has been successfully demonstrated.

Patent Status

Related Materials

• M.R. Hicks, J. Hiserodt, K. Paras, W.Fujiwara, A. Eskin, M. Jan, H. Xi, C. S. Young, D. Evseenko, S.F. Nelson, M.J. Spencer, B.V. Handel, A.D. Pyle, ERBB3 and NGFR mark distinct skeletal muscle progenitor cells in human development enabling enrichment and maturation of hPSC muscle, Nature Cell Biology, 2017.
• C.S. Young, M.R. Hicks, N.V. Ermolova, H. Nakano, M. Jan, S. Younesi, S. Karumbayaram, C. Kumagai-Cresse, D. Wang, J.A. Zack, D. Kohn, A. Nakano, S.F. Nelson, M.C. Miceli, M.J. Spencer, A.D. Pyle, A single CRISPR-Cas9 deletion strategy that targets the majority of DMD patients restores dystrophin function in hiPSC-derived muscle cells, Cell Stem Cell, 2016.
• M.R. Hicks, A.D. Pyle, The Path from Pluripotency to Skeletal Muscle: Developmental Myogenesis Guides the Way, Cell Stem Cell, 2015.