Production of a novel recombinant cell line for use as a bioassay system for detection of 2,3,7,8‐tetrachlorodibenzo‐P‐dioxin‐like chemicals

Abstract

Exposure to specific halogenated aromatic hydrocarbons (HAHs), such as 2,3,7,8 tetrachlorodibenzo‐p‐dioxin (TCDD), can produce a wide variety of species‐ and tissue specific toxic and biological effects The presence of HAHs in environmental samples as complex mixtures has made it difficult to predict the biological and toxic potency of these chemicals We have used aspects of the molecular mechanism of action of these chemicals to develop a species‐specific bioassay system for detection of bioactive HAHs in complex mixtures Here we describe construction and utilization of a recombinant expression vector that responds to these HAHs with the induction of an easily measurable gene product, heat‐stable human placental alkaline phosphatase (PAP) This vector contains the PAP gene under TCDD‐inducible control of four dioxin‐responsive DNA enhancer elements HAH inducible expression of PAP from the recombinant vector occurs in a dose‐ and Ah‐receptor‐ (AhR‐) dependent manner Stable transfection of this vector into mouse hepatoma cells has produced a novel cell line in which AhR‐dependent induction of gene expression can easily be measured This transfected cell line can readily be used for detection and relative quantitation of AhR agonists in complex mixtures of environmental and biological samples and for identification and characterization of novel AhR agonists

An in vitro rainbow trout cell bioassay for aryl hydrocarbon receptor‐mediated toxins

“…The time course of induction was significantly slower than that observed in mammalian cells [15,27,28]. This slower induction may result from the low levels of AhR present in RTH‐149 cells as compared to most mammalian cells, or from species‐specific differences in regulatory factors present in these cells.…”

The potential of mechanism-based bioanalytical tools in ecotoxicological exposure and effect assessment

“…[47,48,49]). For instance, to measure the dioxin-like activity, recombinant yeast cells, continuous teleostean and rodent cell lines and primary cell cultures from fish, birds and mammals have been used [50,51,52,53,54,55,56]. Differences of the gene induction response among cell systems derived from various species have been reported [53,54,57,58], which may relate to species-dependent ligandbinding affinity, in the expression level and structure of the receptors and their associated proteins, and in the ac-392 Fig.…”

Recent Developments in Immunoassays and Related Methods for the Detection of Xenobiotics

“…Molecular modeling techniques are being used to help design improved TCDD haptens and surrogate standards(4tf). Toxicities of surrogate standards developed in this project are being assessed using a cell-based bioassay which uses induced expression of a luciferase gene to indicate aromatic hydrocarbon receptor-mediated toxicity of TCDD analogs (49). Figure 8 shows a representative set of haptens and surrogate standards that have been synthesized for this project.…”