Engineering skeletal muscle tissues with advanced maturity improves synapse formation with human induced pluripotent stem cell-derived motor neurons
Abstract
To develop effective cures for neuromuscular diseases, human-relevant in vitro models of neuromuscular tissues are critically needed to probe disease mechanisms on a cellular and molecular level. However, previous attempts to co-culture motor neurons and skeletal muscle have resulted in relatively immature neuromuscular junctions (NMJs). In this study, NMJs formed by human induced pluripotent stem cell (hiPSC)-derived motor neurons were improved by optimizing the maturity of the co-cultured muscle tissue. First, muscle tissues engineered from the C2C12 mouse myoblast cell line, cryopreserved primary human myoblasts, and freshly isolated primary chick myoblasts on micromolded gelatin hydrogels were compared. After three weeks, only chick muscle tissues remained stably adhered to hydrogels and exhibited progressive increases in myogenic index and stress generation, approaching values generated by native muscle tissue. After three weeks of co-culture with hiPSC-derived motor neurons, engineered chick muscle tissues formed NMJs with increasing co-localization of pre- and postsynaptic markers as well as increased frequency and magnitude of synaptic activity, surpassing structural and functional maturity of previous in vitro models. Engineered chick muscle tissues also demonstrated increased expression of genes related to sarcomere maturation and innervation over time, revealing new insights into the molecular pathways that likely contribute to enhanced NMJ formation. These approaches for engineering advanced neuromuscular tissues with relatively mature NMJs and interrogating their structure and function have many applications in neuromuscular disease modeling and drug development.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jul 13, 2021
- Source ID
- 10.1063/5.0054984
Entities
People
- Dion Dickman
- Divya Gupta
- Eric Hendricks
- Gio C. Suh
- Jeffrey W. Santoso
- Justin K Ichida
- Megan L McCain
- Sarah L. Perry
- Shaoyu Lin
- Xiling Li
Organizations
- ALS Association
- Alzheimer's Drug Discovery Foundation
- Association for Frontotemporal Degeneration
- Donald E. and Delia B. Baxter Foundation
- Judith and Jean Pape Adams Charitable Foundation
- Keck School of Medicine of USC
- Muscular Dystrophy Association
- National Institute of Neurological Disorders and Stroke
- National Science Foundation
- New York Stem Cell Foundation
- Rose Hills Foundation
- United States Department of Defense
- University of Southern California