Developmental and Reproductive Biology Graduate Program, Institute for Biogenesis Research, John A. Burns School of Medicine, University of Hawaii, Honolulu, Hawaii, USA.
Toxicol Sci. 2017 May 1;157(1):235-245. doi: 10.1093/toxsci/kfx034.
Establishment of effective non-animal alternatives for developmental toxicity screening assays is desirable to ensure maternal and fetal health outcomes. Validation of such assays requires a comparison between the in vitro responses to chemical exposures and the in vivo impacts of the corresponding compounds at equivalent concentrations. Here, we investigated how the P19C5 gastrulation model responds to 24 compounds at specific concentrations, some of which are categorized as positive exposures based on previously observed detrimental effects on development in vivo, whereas others are categorized as negative exposures due to lack of effects in vivo. The P19C5 gastrulation model consists of in vitro morphogenesis of mouse stem cells aggregated into embryoid bodies (EBs), which recapitulates growth and axial elongation of early embryos during four days of three-dimensional culture. Adverse impacts of chemical exposures were defined as: death, impaired growth, and altered axial elongation of EBs. Ten out of 17 positive exposures caused adverse impacts on EBs. In contrast, only three out of 17 negative exposures adversely affected EBs, although two of the three diminished viability of somatic cell lines (NIH/3T3, HEK293, and JEG3), suggesting general cytotoxicity. Overall, the study showed that 24 out of 34 exposures impacted EB development in a manner concordant with the in vivo developmental effects. Validation of other alternative assays using the same set of chemical exposures will provide information on the strengths and weaknesses of each assay, and should help determine the most effective ensemble of assays to detect a wide range of developmentally toxic exposures.
建立有效的非动物替代方法来进行发育毒性筛选测试是很有必要的，这可以确保母婴健康。此类测试的验证需要将化学暴露的体外反应与相应化合物在等效浓度下的体内影响进行比较。在这里，我们研究了 P19C5 原肠胚形成模型对 24 种特定浓度化合物的反应，其中一些化合物根据先前在体内观察到的对发育的有害影响被归类为阳性暴露，而另一些化合物由于在体内缺乏影响而被归类为阴性暴露。P19C5 原肠胚形成模型由聚集形成类胚体（EBs）的小鼠干细胞的体外形态发生组成，它在三维培养的四天内重现了早期胚胎的生长和轴向伸长。化学暴露的不良影响被定义为：EB 死亡、生长受损和轴向伸长改变。17 种阳性暴露中有 10 种对 EBs 产生了不良影响。相比之下，17 种阴性暴露中只有 3 种对 EBs 产生不利影响，尽管其中两种降低了体细胞系（NIH/3T3、HEK293 和 JEG3）的活力，表明存在普遍的细胞毒性。总的来说，该研究表明，在 34 种暴露中，有 24 种以与体内发育效应一致的方式影响 EB 发育。使用相同的化学暴露集对其他替代测试进行验证将提供关于每种测试的优缺点的信息，并应有助于确定最有效的测试组合，以检测广泛的发育毒性暴露。
