Human Umbilical Cord Blood-Derived Neural Stem Cell Line as a Screening Model for Toxicity

The aim was to investigate whether a human neural stem cell (NSC) line derived from human umbilical cord blood (hUCB) can be used for toxicity study. Toxicity of both neurotoxic environmental xenobiotics, methyl mercury chloride (CH 3 HgCl), lead acetate (CH 3 COOPb), and chlorpyrifos (CP), and non-neurotoxic insecticide, dichlorvos, as well as non-neurotoxic drugs, theophylline and acetaminophen were assessed. Additionally, differentiation of neuronal and glial cell lines derived from hUCB was elucidated. It was observed that CH 3 HgCl was more toxic to human NSCs in comparison to CH 3 COOPb and CP. The minimum inhibitory concentration (MIC) value against NSCs was 3, 10, and 300 mg/L, in each staining process, acridine orange/ethidium bromide (AO/EB) staining, 3-(4,5-dimethylthiazol-2-yl)2,5-diphenyl tetrazolium bromide (MTT) assay, and Hoechst staining, for CH 3 HgCl, CP, and CH 3 COOPb, respectively. CH 3 HgCl had the LC 25 value as 10.0, 14.4, and 12.7 mg/L, by staining method mentioned in succession. CP had the LC 25 value as 21.9, 23.7, and 18.4 mg/L; similarly, CH 3 COOPb had LC 25 values, successively as 616.9, 719.2, and 890.3 mg/L. LC 50 values ranged from 18.2 to 21.7 mg/L for CH 3 HgCl, 56.4 to 60.2 mg/L for CP, and 1000 to 1460.1 for CH 3 COOPb. Theophylline, acetaminophen, and dichlorvos had no impact on the viability of NSCs. This work justified that hUCB-NSC model can be used for toxicity study.