Fig 2: Differentiation and neuronal activity of iNSC neural spheroid in chip. (a) The mRNA expression of neuronal markers (TUJ1, MAP2, NF, and TBR2) was determined using quantitative PCR. The unpaired, two‐tailed t test to compare the spheroid in chip at Day 14 with the spheroid in chip at Day 3. (b–f) The expression of the neural progenitor (SOX2, b) and neuronal markers (TBR2, c; TUJ1, d; NF‐H, e; MAP2, f) was verified by immunostaining. Scale bar = 500 μm. (g) The mRNA expression of glial markers (GFAP and OLIG2) was determined using quantitative PCR. The unpaired, two‐tailed t test to compare the spheroid in chip at Day 14 with the spheroid in chip at Day 3. (h) The expression of the neuronal activity (c‐fos) was verified by immunostaining. We compared the intensity of spheroid in chip at day 14 with the spheroid in chip at Day 3. All experiments were performed in triplicate (N = 3). The results are presented as the means ± SD. **p < 0.01 and ***p < 0.001