A high-throughput and highly automated genotoxicity screening assay

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Renxiang Chen
Yun-Tien Lin
Albert J. Fornace Jr.
Heng-Hong Li


The increasing number of compounds under development and chemicals in commerce that require safety assessments pose a serious challenge for regulatory agencies worldwide. In vitro screening using toxicogenomic biomarkers has been proposed as a first-tier screen in chemical assessments and has been endorsed internationally. We previously developed, evaluated, and validated an in vitro transcriptomic biomarker responsive to DNA-damage-inducing (DDI) agents, namely TGx-DDI, for genotoxicity testing in human cells, and demonstrated the feasibility of using TGx-DDI in a medium-throughput, cell-based genotoxicity testing system by implementing this biomarker with the Nanostring nCounter system. In this current study, we took the advantage of Nanostring nCounter Plexset technology to develop a highly automated, multiplexed, and high-throughput genotoxicity testing assay, designated as the TGx-DDI Plexset assay, which can increase the screening efficiency by eight-fold compared to standard nCounter technology while decreasing the hands-on time. We demonstrated the high-throughput capability of this assay by eliminating concentration determination and RNA extraction steps without compromising the specificity and sensitivity of TGx-DDI. Thus, we propose that this simple, highly automated, multiplexed high-throughput pipeline can be widely used in chemical screening and assessment. 

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Chen, R., Lin, Y.-T., Fornace , A. J. . and Li , H.-H. (2021) “A high-throughput and highly automated genotoxicity screening assay”, ALTEX - Alternatives to animal experimentation. doi: 10.14573/altex.2102121.

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