Fig 1: Human cerebral organoids comprise diverse cell types relevant to the study of neuronal circuit development and physiology. (a) Immunohistochemistry (IHC) revealed the presence of mature neurons (Tau/NeuN), astrocytes (GFAP), and oligodendrocytes (OLIG2) after 100 days of differentiation; nuclei were stained with DAPI (in blue). Scale bars are 50 µm. (b) Quantification of NeuN-positive cells. The ratio of the number of NeuN-positive cells to the total number of cells was quantified for both hCO lines (3 hCOs per line, for each hCO > 5000 cells). The ratio of NeuN-positive cells to total cells did not differ significantly between the two lines. (c) Single-cell RNA sequencing (scRNA-seq) was performed to quantify the cellular composition of hCOs and their comparability. The results are summarized in two pie charts with the identified cell type fractions displayed for each line. For both lines the results confirmed the presence of dopaminergic, GABAergic, glutamatergic and cholinergic neurons, neural crest cells (NCCs), radial glia (RG), astrocytes and oligodendrocytes.