Centre for Health Protection, National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands; Institute for Risk Assessment Sciences (IRAS), Utrecht University, Utrecht, the Netherlands.
Centre for Health Protection, National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands.
Toxicology. 2021 Apr 30;454:152735. doi: 10.1016/j.tox.2021.152735. Epub 2021 Feb 23.
Animal-free assessment of compound-induced developmental neurotoxicity will most likely be based on batteries of multiple in vitro tests. The optimal battery is built by combining tests with complementary biological domains that together ideally cover all relevant toxicity pathways. Thus, biological domain definition, i.e. which biological processes and cell types are represented, is an important assay characteristic for determining the place of assays in testing strategies. The murine neural embryonic stem cell test (ESTn) is employed to predict the developmental neurotoxicity of compounds. The aim of this study was to explore the biological domain of ESTn according to three groups of biomarker genes of early (neuro)development: morphogenetic regulators, Hox genes and cell type markers for the ectodermal and neural lineages. These biomarker groups were selected based on their crucial regulatory role in (neuro)development. Analysis of these genes in a series of previously generated whole transcriptome datasets of ESTn showed that at day 7 in culture cell differentiation resembled hindbrain/branchial/thoracic development between E6.5-E12.5 in vivo, with subsequent development into a mixed cell culture containing different neural subtypes, astrocytes and oligodendrocytes by day 13. In addition, the selected biomarkers showed common and distinct responses to compound exposure. Monitoring the biological domain of ESTn through gene expression patterns of morphogenetic regulators, Hox genes and cell type markers proved instrumental in providing mechanistic understanding of compound effects on neural differentiation in ESTn, and can aid in positioning of the test in a battery of complementary in vitro tests in integrated approaches to testing and assessment.
无动物评估化合物诱导的发育神经毒性很可能基于多种体外测试的组合。最佳的组合是通过将具有互补生物学领域的测试相结合来构建的，这些测试理想地涵盖了所有相关的毒性途径。因此，生物学领域的定义，即代表哪些生物学过程和细胞类型，是确定测试在测试策略中的位置的重要测试特征。鼠神经胚胎干细胞测试（ESTn）用于预测化合物的发育神经毒性。本研究的目的是根据早期（神经）发育的三组生物标志物基因（形态发生调节剂、Hox 基因和外胚层和神经谱系的细胞类型标志物）来探索 ESTn 的生物学领域。这些生物标志物组是基于它们在（神经）发育中的关键调节作用而选择的。对 ESTn 一系列先前生成的全转录组数据集的这些基因进行分析表明，在培养第 7 天，细胞分化类似于体内 E6.5-E12.5 的后脑/鳃/胸发育，随后在培养第 13 天发展为含有不同神经亚型、星形胶质细胞和少突胶质细胞的混合细胞培养物。此外，所选生物标志物对化合物暴露表现出共同和独特的反应。通过形态发生调节剂、Hox 基因和细胞类型标志物的基因表达模式监测 ESTn 的生物学领域，有助于深入了解化合物对 ESTn 中神经分化的影响，并有助于确定该测试在综合测试和评估中一系列互补的体外测试中的位置。
