Highly sensitive reporter gene assay for dioxins in human plasma by using cycloheximide as an enhancer substance.

A reporter gene assay (RGA) that uses a mouse liver recombinant Hepa1c1c7 containing the firefly luciferase gene was developed to screen for dioxins in human plasma. For a high-sensitivity method, the addition of cycloheximide to the culture medium brought about a fivefold increase in the sensitivity. The detection limit was 0.1 pg/microL/well. Aryl hydrocarbon receptor (AhR) binding affinity factors (AhR-BAF), calculated from the effect concentration 50 (EC(50)) value, showed approximately the same values as those in WHO-TEF (2006). A significant correlation between RGA and the conventional gas chromatography/mass spectrometry (GC/MS) method was obtained.