Generating and characterizing human telencephalic brain organoids from stem cell-derived single neural rosettes.

We have developed a method for generating human telencephalic organoids from stem cell-derived isolated single neural rosettes. The use of single neural rosettes for generating organoids offers several important advantages. First, it mimics the development of neural tissue from a singular neural tube in vivo. Second, single neural rosette-derived organoids exhibit a relatively consistent and reproducible composition of telencephalic neural cells. Finally, single neural rosette-derived organoids demonstrate predictable organization of the identified neural cells around a single neural rosette-derived lumen and contain a large proportion of functionally mature neurons that generate action potentials and receive both excitatory and inhibitory synaptic inputs. These unique features of our protocol enable the study of the specification and organization of different neural cells in the developing human telencephalon, as well as modeling of neurodevelopmental disorders associated with disrupted neural networks. Here, we describe our protocols for generating CRISPR-Cas9-engineered human stem cells with a hemizygous SHANK3 deletion, stem cell-derived single neural rosettes and telencephalic brain organoids. We also offer insights on how to conduct single-cell RNA sequencing, immunohistochemistry and slice patch-clamp electrophysiology on these organoids. Completion of the protocols takes 5-6 months and requires experience working with cultured cells. We expect this protocol will prove useful for studies of human brain development and disease, as well as for advancing the development of new organoid-based biocomputers.