title: Perspectives on validation of high-throughput assays supporting 21st century toxicity testing.
abstract: In vitro high-throughput screening (HTS) assays are seeing increasing use in toxicity testing. HTS assays can simultaneously test many chemicals but have seen limited use in the regulatory arena, in part because of the need to undergo rigorous, time-consuming formal validation. Here we discuss streamlining the validation process, specifically for prioritization applications. By prioritization, we mean a process in which less complex, less expensive, and faster assays are used to prioritize which chemicals are subjected first to more complex, expensive, and slower guideline assays. Data from the HTS prioritization assays is intended to provide a priori evidence that certain chemicals have the potential to lead to the types of adverse effects that the guideline tests are assessing. The need for such prioritization approaches is driven by the fact that there are tens of thousands of chemicals to which people are exposed, but the yearly throughput of most guideline assays is small in comparison. The streamlined validation process would continue to ensure the reliability and relevance of assays for this application. We discuss the following practical guidelines: (1) follow current validation practice to the extent possible and practical; (2) make increased use of reference compounds to better demonstrate assay reliability and relevance; (3) de-emphasize the need for cross-laboratory testing; and (4) implement a web-based, transparent, and expedited peer review process.
authors: National Center for Computational Toxicology, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711, USA. judson.richard@epa.gov
authors: Richard
authors: R
authors: Judson
authors: Robert
authors: R
authors: Kavlock
authors: Matthew
authors: M
authors: Martin
authors: David
authors: D
authors: Reif
authors: Keith
authors: K
authors: Houck
authors: Thomas
authors: T
authors: Knudsen
authors: Ann
authors: A
authors: Richard
authors: Raymond R
authors: RR
authors: Tice
authors: Maurice
authors: M
authors: Whelan
authors: Menghang
authors: M
authors: Xia
authors: Ruili
authors: R
authors: Huang
authors: Christopher
authors: C
authors: Austin
authors: George
authors: G
authors: Daston
authors: Thomas
authors: T
authors: Hartung
authors: John R
authors: JR
authors: Fowle
authors: William
authors: W
authors: Wooge
authors: Weida
authors: W
authors: Tong
authors: David
authors: D
authors: Dix
mesh_terms: D000826:Animal Testing Alternatives / Q000379:methods* / Q000592:standards* / Q000639:trends; D000818:Animals; D057166:High-Throughput Screening Assays / Q000379:methods* / Q000592:standards / Q000639:trends; D006801:Humans; D015203:Reproducibility of Results; D018675:Toxicity Tests / Q000379:methods* / Q000592:standards* / Q000639:trends