A digitally programmable 3D microenvironment directs satellite cell function

Skeletal muscle stem cells, also known as satellite cells, have remarkable self-renewal abilities in response to muscle injury, playing a vital role in muscle regeneration and repair. However, disruptions in the satellite cell niche caused by severe trauma or surgery can hinder natural regeneration. Additionally, challenges such as limited availability of human donors and primary cells, difficulties in scaling satellite cell expansion, and storage issues present significant barriers. Therefore, developing engineered platforms that create optimized micro-niche environments to support muscle stem cells and promote muscle cell activity is crucial. Using non-direct 3D printing-guided phase separation technology and skeletal muscle extracellular matrix (ECM) hydrogel, we developed a digitally programmable, user-friendly, customizable, and biofunctional 3D platform that mimics the hierarchical porous structure and microenvironment of natural ECM. Notably, the synergistic combination of natural and synthetic matrices improves scalable satellite cell growth, supports autonomous myotube contraction, and accelerates in vivo myofiber and blood vessel formation, paving the way for increased production of myogenic precursors, cell therapies, and treatments for traumatic muscle injuries.