Article

Compound Cytotoxicity Profiling Using Quantitative High-Throughput Screening

NIH Chemical Genomics Center, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland 20892-3370, USA.
Environmental Health Perspectives (Impact Factor: 7.98). 04/2008; 116(3):284-91. DOI: 10.1289/ehp.10727
Source: PubMed

ABSTRACT

The propensity of compounds to produce adverse health effects in humans is generally evaluated using animal-based test methods. Such methods can be relatively expensive, low-throughput, and associated with pain suffered by the treated animals. In addition, differences in species biology may confound extrapolation to human health effects.
The National Toxicology Program and the National Institutes of Health Chemical Genomics Center are collaborating to identify a battery of cell-based screens to prioritize compounds for further toxicologic evaluation.
A collection of 1,408 compounds previously tested in one or more traditional toxicologic assays were profiled for cytotoxicity using quantitative high-throughput screening (qHTS) in 13 human and rodent cell types derived from six common targets of xenobiotic toxicity (liver, blood, kidney, nerve, lung, skin). Selected cytotoxicants were further tested to define response kinetics.
qHTS of these compounds produced robust and reproducible results, which allowed cross-compound, cross-cell type, and cross-species comparisons. Some compounds were cytotoxic to all cell types at similar concentrations, whereas others exhibited species- or cell type-specific cytotoxicity. Closely related cell types and analogous cell types in human and rodent frequently showed different patterns of cytotoxicity. Some compounds inducing similar levels of cytotoxicity showed distinct time dependence in kinetic studies, consistent with known mechanisms of toxicity.
The generation of high-quality cytotoxicity data on this large library of known compounds using qHTS demonstrates the potential of this methodology to profile a much broader array of assays and compounds, which, in aggregate, may be valuable for prioritizing compounds for further toxicologic evaluation, identifying compounds with particular mechanisms of action, and potentially predicting in vivo biological response.

Download full-text

Full-text

Available from: Raymond R Tice
    • "The CellTiter-Glo Luminescent Cell Viability (Promega, Madison, WI) assay was used to assess intracellular ATP concentration, a marker for cytotoxicity, 40 h post treatment. Time points were selected based on previous experiments at the National Institutes of Health Chemical Genomics Center (Xia et al., 2008). A ViewLux plate reader (PerkinElmer, Shelton, CT) was used to detect luminescent intensity. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Population-based human in vitro models offer exceptional opportunities for evaluating the potential hazard and mode of action of chemicals, as well as variability in responses to toxic insults among individuals. This study was designed to test the hypothesis that comparative population genomics with efficient in vitro experimental design can be used for evaluation of the potential for hazard, mode of action, and the extent of population variability in responses to chemical mixtures. We selected 146 lymphoblast cell lines from 4 ancestrally and geographically diverse human populations based on the availability of genome sequence and basal RNA-seq data. Cells were exposed to two pesticide mixtures - an environmental surface water sample comprised primarily of organochlorine pesticides and a laboratory-prepared mixture of 36 currently used pesticides - in concentration response and evaluated for cytotoxicity. On average, the two mixtures exhibited a similar range of in vitro cytotoxicity and showed considerable inter-individual variability across screened cell lines. However, when in vitro-to-in vivo extrapolation (IVIVE) coupled with reverse dosimetry was employed to convert the in vitro cytotoxic concentrations to oral equivalent doses and compared to the upper bound of predicted human exposure, we found that a nominally more cytotoxic chlorinated pesticide mixture is expected to have greater margin of safety (more than 5 orders of magnitude) as compared to the current use pesticide mixture (less than 2 orders of magnitude) due primarily to differences in exposure predictions. Multivariate genome-wide association mapping revealed an association between the toxicity of current use pesticide mixture and a polymorphism in rs1947825 in C17orf54. We conclude that a combination of in vitro human population-based cytotoxicity screening followed by dosimetric adjustment and comparative population genomics analyses enables quantitative evaluation of human health hazard from complex environmental mixtures. Additionally, such an approach yields testable hypotheses regarding potential toxicity mechanisms.
    No preview · Article · Sep 2015 · Environment international
  • Source
    • "In general, cell quantification and viability measurement data generated with the xCELLigence system correlates well with those from the MTT assay (Xing et al., 2005). Normally exposure to a chemical induces a drop in the xCELLigence-determined CI (Xia et al., 2008). However, in this study Polydadmac induced a distinct and unexpected increase in CI, suggesting that the polymer deposited non-adherent primary cells in a monolayer configuration and thereby increased the impedance or contributed to tighter adhesion between cultured cells leading to increased CI. "
    [Show abstract] [Hide abstract]
    ABSTRACT: To speed up sedimentation of suspended solids the mining industry often uses flocculent chemicals. In this work we evaluated the cytotoxic and mechanistic effects of Polydadmac, and its basic component Dadmac, on fish cells. Dose-response effects, temperature-dependent effects and impact of Dadmac and Polydadmac on Cu toxicity were studied in Atlantic salmon hepatocytes. We used the xCELLigence system and the MTT test for cytotoxicity assessments, and real-time RT-qPCR to evaluate molecular effects. The results showed a cytotoxic response for Polydadmac but not for Dadmac. Elevated levels of Cu were cytotoxic. Moderately cytotoxic concentrations of Cu (100-1000μM) induced significant responses on the transcription of a number of genes in the cells, i.e. cuznsod (sod1), cat, mnsod (sod2), nfe2l2, hmox1, mta, casp3b, casp6, bclx, cyp1a, ccs, atp7a, app, mmp13, esr1, ppara, fads2 and ptgs2. A factorial PLS regression model for mnsod transcription showed a synergistic effect between Dadmac and Cu exposure in the cells, indicating an interaction effect between Dadmac and Cu on mitochondrial ROS scavenging. No interaction effects were seen for Polydadmac on Cu toxicity. In conclusion, Polydadmac is cytotoxic at elevated concentrations but appears to have low ability to interfere with Cu toxicity in Atlantic salmon liver cells.
    Full-text · Article · Sep 2015 · Toxicology in Vitro
  • Source
    • "For example, the sets of genes that control forebrain expansion and regulate human cell fate are largely absent in rodents. Also, fibroblast growth factor (FGF) has different effects on myelination in humans and rodents (Hu et al., 2009), and compounds that are toxic to rodent cells may have no effect on human cells or vice versa (Malik et al., 2014; Xia et al., 2008). "
    [Show abstract] [Hide abstract]
    ABSTRACT: Induced pluripotent stem cells (iPSC) and their differentiated derivatives offer a unique source of human primary cells for toxicity screens. Here, we report on the comparative cytotoxicity of 80 compounds (neurotoxicants, developmental neurotoxicants, environmental compounds) in iPSC as well as isogenic iPSC-derived neural stem cells (NSC), neurons, and astrocytes. All compounds were tested over a 24-hour period at 10 and 100μM, in duplicate, with cytotoxicity measured using the MTT assay. Of the 80 compounds tested, 50 induced significant cytotoxicity in at least one cell type; per cell type, 32, 38, 46, and 41 induced significant cytotoxicity in iPSC, NSC, neurons, and astrocytes, respectively. Four compounds (valinomycin, 3,3',5,5'-tetrabromobisphenol, deltamethrin, triphenyl phosphate) were cytotoxic in all four cell types. Retesting these compounds at 1, 10, and 100μM using the same exposure protocol yielded consistent results as compared with the primary screen. Using rotenone, we extended the testing to seven additional iPSC lines of both genders; no substantial difference in the extent of cytotoxicity was detected among the cell lines. Finally, the cytotoxicity assay was simplified by measuring luciferase activity using lineage-specific luciferase reporter iPSC lines which were generated from the parental iPSC line. Copyright © 2015. Published by Elsevier B.V.
    Full-text · Article · Aug 2015 · Brain research
Show more