SPECIES-SPECIFIC THIRD GENERATION (G3) LUCIFERASE CELL BIOASSAYS SHOW DRAMATICALLY INCREASED SENSITIVITY AND MAGNITUDE OF RESPONSE TO TCDD AND OTHER AH RECEPTOR AGONISTS
2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD, dioxin) and related dioxin-like chemicals are widespread and persistent environmental contaminants that can cause a variety of species- and tissue-specific toxic and biological effects. Most of these effects are mediated by the Ah receptor (AhR) and involve binding of liganded AhR complex to its specific DNA recognition site and activation of gene transcription. Although the chemically activated luciferase expression (CALUX) bioassay has been used extensively for the directly detection of dioxin-like chemicals from a variety of environmental and biologic materials, the response of the CALUX bioassay at very low dioxin-like chemical levels is inadequate to screening of extracts with low levels of contamination. We have developed novel AhR-responsive luciferase reporter plasmids with increased numbers of DREs and stable transfection of a plasmid containing 20 DREs into a variety of cell lines has produced a series of species-specific cell bioassay systems with a dramatically increased luciferase induction response compared to existing CALUX-type cell lines. The minimal detection limit for TCDD in stably transfected mouse hepatoma (H1L7.5 c3) cells was 100- to 250-fold lower than that of the currently used H1L6.1c2 cells. Overall, these new cell lines have application for the detection of very low levels of dioxin-like chemicals.
Guochun He Tomoaki Tsutsumi Bin Zhao David S.Baston Michael S.Denison
Department of Environmental Toxicology,Meyer Hall,University of California,Davis,CA 95616,USA Division of Foods,National Institute of Health Sciences,Kamiyoga 1-18-1,Setagaya-ku,Tokyo,Japan
国际会议
北京
英文
1-5
2009-08-24（万方平台首次上网日期，不代表论文的发表时间）