The DNT-EST: A predictive embryonic stem cell test for developmental neurotoxicity testing in vitro

As the developing brain is exquisitely vulnerable to chemical disturbances, testing for developmental neurotoxicity of a substance is an important aspect of characterizing its tissue specific toxicity. Embryonic stem cells can be differentiated toward a neural phenotype, and this can be used as a model for early brain development. We developed a new in vitro assay using mouse embryonic stem cells (mESC) to predict adverse effects of chemicals and other compounds on neural development – the so-called DNT-EST (Visan et al., 2012; Hayess et al., 2013). After treatment of neurally differentiating stem cells for 48 h or 72 h at two key developmental stages, endpoints for neural differentiation, viability and proliferation were assessed. As a reference, we treated undifferentiated stem cells in parallel, also measuring viability and proliferation. Here, we show that chemical testing of a training set comprising nine substances allows the formulation of a mathematical prediction model that can discriminate positive from negative DNT compounds with an in vivo – in vitro concordance of 100%. Based on these results our current work aims to establish three-dimensional cortical tissues from embryonic stem cells to better model the complexity of the central nervous system for in vitro neurotoxicity assays