Fig. 1

Generation and implantation procedure of novel artificial nerves with motor and sensory neurite bundles. a Schematic diagram of creating nerve organoids with neurite bundles derived from spheroids. b Whole image of the nerve organoid cultured in the microfluidic device. Scale bar = 300 μm. c, Schematic explanation of the procedure for neurite bundle-derived artificial nerve creation by removing spheroids that contained cell bodies from the nerve organoids. d The implantation procedure of a nerve conduit tube at the transected sciatic nerve with a 13 mm gap. e Immunofluorescence images of ChAT and Islet1/2 staining of motor neuron spheroids derived from hiPSCs. Scale bars = 100 μm. f Quantitative analysis of ChAT- and Islet1/2-positive cells in pan-ELAVL-positive cells. g Immunofluorescence images of TrkA, TrkB, TrkC, PV (parvalbumin) and CGRP staining of sensory neuron spheroids derived from hiPSCs. Scale bars = 100 μm. h Quantitative results of TrkA-, TrkB-, TrkC-, PV (parvalbumin)- and CGRP-positive cells in pan-ELAVL-positive cells. i, Electron microscopic images of the axial section from motor and sensory neurite bundles consisting of condensed neural fibers. Scale bars = 1 μm. j Neurite diameter distribution in motor and sensory neurite bundles. Arrowheads indicate the position of the average diameter. k Average neurite density in neurite bundles. l, m Average ratio of neurofilaments’ area (l) and microtubules’ area (m) in neurite area. (n = 5) *p < 0.05, N.S. = not significant. Data are represented as the mean ± standard error of the mean (SEM)