Self-Organizing 3D Human Trunk Neuromuscular Organoids

Area of Science:

• Developmental biology
• Stem cell research
• Neuroscience

Background:

• Human neuromuscular networks are crucial for body movement and form during embryonic development.
• Previous models using human pluripotent stem cells (hPSCs) created either spinal cord neurons or skeletal muscle cells separately in 2D cultures.
• Limitations existed in recapitulating the complex, integrated nature of neuromuscular systems.

Purpose of the Study:

• To develop a novel 3D model for studying human neuromuscular development and function.
• To create self-organizing human neuromuscular organoids (NMOs) capable of long-term maintenance.
• To establish a platform for modeling neuromuscular diseases.

Main Methods:

• Utilized hPSC-derived axial stem cells to simultaneously generate spinal cord neurons and skeletal muscle cells.
• Cultured these cells in 3D to promote self-organization into NMOs.
• Employed single-cell RNA-sequencing to analyze differentiation trajectories and reproducibility.
• Assessed functional properties including contractions and neuronal circuit formation.

Main Results:

• Successfully generated reproducible human neuromuscular organoids (NMOs) from hPSC-derived axial stem cells.
• NMOs contain functional neuromuscular junctions with terminal Schwann cells and exhibit spontaneous contractions.
• Organoids developed central pattern generator-like neuronal circuits.
• NMOs successfully recapitulated key pathological features of myasthenia gravis.

Conclusions:

• Human neuromuscular organoids (NMOs) provide a robust, reproducible 3D model for studying human neuromuscular development.
• NMOs offer a powerful platform for investigating neuromuscular diseases, including myasthenia gravis.
• This model system holds significant potential for future drug screening and therapeutic development in neuromuscular disorders.