Sensorimotor Organoids for Neuromuscular Disease

Human induced pluripotent stem cells (iPSCs) hold substantial promise for modeling diseases in the relevant human genetic backgrounds. Here, we leverage the shared developmental pathways of spinal neuroectoderm and paraxial mesoderm via neuromesodermal precursors to produce a sensorimotor organoid model, which we validate with single-cell RNA sequencing and physiology in multiple control and diseased human stem cell lines. The organoids contain motor neurons and skeletal muscle connected by physiologically functional neuromuscular junctions. We also generate additional neuronal and mesodermal derivatives, identified by RNA-seq cluster analysis and verified by staining, electron microscopy, and physiology. These cell types include astrocytes, endothelial cells, microglia, and sensory neurons, the last from which we record tetrodotoxin-resistant sodium currents and capsaicin-elicited calcium flux. The physiological resolution of the neuromuscular junction synapse combined with the generation of major cellular cohorts exerting autonomous and non-cell autonomous effects in motor and sensory diseases may prove valuable for more comprehensive disease modeling.