A Self-Renewing Biomimetic Skeletal Muscle Construct Engineered using Induced Myogenic Progenitor Cells

Area of Science:

• Biomaterials Engineering
• Regenerative Medicine
• Cell Biology

Background:

• Skeletal muscle regeneration relies on myogenic stem cells, but in vitro models mimicking this process, including self-renewal and aligned myotube formation, are challenging.
• Existing models often fail to replicate the complex cellular heterogeneity and organized structure of native muscle tissue.

Purpose of the Study:

• To engineer a biomimetic skeletal muscle construct capable of self-regeneration and producing aligned myotubes in vitro.
• To utilize induced myogenic progenitor cells (iMPCs) and electrospun polycaprolactone (PCL) scaffolds to create a functional muscle tissue model.
• To investigate the myogenic differentiation program and regenerative capacity of the engineered construct.

Main Methods:

• Fabrication of polycaprolactone (PCL) substrates using electrospinning to control fiber orientation.
• Culturing induced myogenic progenitor cells (iMPCs) on PCL scaffolds to promote differentiation into aligned myotubes.
• Supplementation with Matrigel to enhance stem cell differentiation capacity.
• Single-cell RNA-sequencing (scRNA-seq) to analyze the myogenic differentiation pathway.
• Assessment of construct regeneration following exposure to a myonecrotic agent.

Main Results:

• Engineered constructs successfully produced organized, multinucleated myotubes alongside self-renewing stem cells.
• Single-cell RNA-sequencing confirmed that iMPC-derived constructs recapitulate a stepwise myogenic differentiation program.
• The constructs demonstrated in vitro regeneration, with stem cells differentiating into aligned myotubes upon damage, mimicking in vivo skeletal muscle repair.
• The protocol was adapted to create human myoblast-derived muscle constructs, indicating translational potential.

Conclusions:

• A novel in vitro skeletal muscle model was developed using iMPCs and PCL scaffolds, capable of self-regeneration and forming aligned myotubes.
• This biomimetic system accurately reflects the myogenic differentiation process and skeletal muscle repair mechanisms.
• The engineered constructs hold promise for basic research into muscle regeneration and for applications in regenerative medicine.