Cranial Neural Crest Cells Three-Dimensional In Vitro Differentiation Protocol for Multiplexed Assay

With their remarkable capacity to generate both ectodermal and mesenchymal derivatives, cranial neural crest cells (CNCC) have attracted a lot of interest in studying the mechanisms regulating cell fate decisions and plasticity. Originating in the dorsal neuroepithelium, this cell population is transient and relatively rare in the developing embryo- making functional tests, genomic screens, and biochemistry assays challenging to perform in vivo. To overcome these limitations, several methods have been developed to model CNCC development in vitro. Neurosphere (NS) based culturing methods provide a complex microenvironment that recapitulates the developing anterior neuroepithelium in 3D. These systems allow the growth of many NS in the same plate to generate a large amount of CNCC, but the produced NS present a high variability in shape, size, and number of CNCC formed- making quantitative assays difficult to perform. This protocol outlines a reproducible method for generating NS from mouse embryonic stem cells (mESC) in a 96-well format. NS generated in 96-well plates produce cranial neural crest cells (CNCC), which can be further cultured. By controlling the number of starting cells, this approach reduces variability in the size and shape between NS and increases reproducibility across experiments. Finally, this culture system is adaptable to several applications and offers a higherdegree of flexibility, making it highly customizable and suitable for multiplexing experimental conditions.