Production of Highly Uniform Midbrain Organoids from Human Pluripotent Stem Cells

Figure 3

Accelerated functional maturation patterns in µMOs. (a) Schematic illustration depicting the procedure for evaluating the formation of neuromelanin-like granules in µMOs. (b) Accumulation of neuromelanin-like granules in µMOs (DIV 30). The neuromelanin-like granules were uniformly formed in all dopamine-treated µMOs (left) but not in untreated µMOs (right). The formation of neuromelanin-like granules was observed on the outside of µMOs. Scale bar, 100 μm. (c) Fontana–Masson staining of µMOs (DIV 30). Cerebral organoid was used as a negative control. Scale bar, 100 μm. (d) Confocal images showing the expression pattern of dopamine in µMOs (DIV 30). Scale bar, 20 μm. (e) Quantification of dopamine release in µMOs (DIV 30 and 60) mnt, minutes. (f, g) Color-mapped raster plots showing neural signals recorded from a 32-channel neural probe in typical MOs (f) on DIV 20, 30, 70, and 130 and µMOs (g) on DIV 20 and 30. (h) Bar graph displaying mean firing rate of neural signals in typical MOs and µMOs on DIV 20 and 30 (n = 5 independent samples for typical MOs, n = 4 independent samples for µMOs on DIV 20, and n = 3 independent samples for µMOs on DIV 30). Data are presented as mean ± SEM. (i) Bar graph displaying synchronization between neural signals recorded from each electrode in µMOs on DIV 20 and 30 (n = 4 independent samples for µMOs on DIV 20 and n = 3 independent samples for µMOs on DIV 30). Data are presented as mean ± SEM. (j) Bar graph displaying the total number of connected electrodes in µMOs on DIV 20 and 30 (n = 4 independent samples for µMOs on DIV 20 and n = 3 independent samples for µMOs on DIV 30). Data are presented as mean ± SEM.

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