FIGURE 2.

Summary of key approaches being utilized synergistically with organoid technology. A cerebellar organoid is shown in the center. Approaches clockwise from top: Rapid developments in single-cell sequencing technologies drive new methods of population profiling. Shown is a tSNE plot constructed from the 10X Million Cell Dataset (data accessible at NCBI GEO database, accession GSM2453144). Pathway analysis is a broad set of approaches commonly utilizing differential expression and gene-set enrichment analysis methods to identify coordinately dysregulated genes as representative of specific pathway perturbations. Transplantation offers a means to test cellular plasticity, lineage commitment, and factors required for terminal differentiation (figure depicting P14 mouse cerebellum has been adapted from the Allen Brain Atlas). Niche bioengineering allows the in vitro reconstruction of elements of the in vivo niche, using approaches such as 3D printing, hydrogels, microfabricated devices, and co-culture. Drug screening stands to benefit from organoids by providing physiologically relevant surrogate model systems for the organ of interest for high-throughput testing. Electrophysiology is a widely adopted tool for establishing neuronal maturity and connectivity (trace adapted from Nayler et al., 2017).