title: Transgenic fluorescent zebrafish Tg(fli1:EGFP)y¹ for the identification of vasotoxicity within the zFET.
abstract: The fish embryo toxicity test (FET) is currently one of the most advocated animal alternative tests in ecotoxicology. To date, the application of the FET with zebrafish (zFET) has focused on acute toxicity assessment, where only lethal morphological effects are accounted for. An application of the zFET beyond acute toxicity, however, necessitates the establishment of more refined and quantifiable toxicological endpoints. A valuable tool in this context is the use of gene expression-dependent fluorescent markers that can even be measured in vivo. We investigated the application of embryos of Tg(fli1:EGFP)(y1) for the identification of vasotoxic substances within the zFET. Tg(fli1:EGFP)(y1) fish express enhanced GFP in the entire vasculature under the control of the fli1 promoter, and thus enable the visualization of vascular defects in live zebrafish embryos. We assessed the fli1 driven EGFP-expression in the intersegmental blood vessels (ISVs) qualitatively and quantitatively, and found an exposure concentration related increase in vascular damage for chemicals like triclosan, cartap and genistein. The fluorescence endpoint ISV-length allowed an earlier and more sensitive detection of vasotoxins than the bright field assessment method. In combination with the standard bright field morphological effect assessment, an increase in significance and value of the zFET for a mechanism-specific toxicity evaluation was achieved. This study highlights the benefits of using transgenic zebrafish as convenient tools for identifying toxicity in vivo and to increase sensitivity and specificity of the zFET.
authors.affiliation: Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Forckenbeckstr. 6, 52074 Aachen, Germany; Institute for Molecular Biotechnology (Biology VII), RWTH Aachen University, Worringerweg 1, 52074 Aachen, Germany. Electronic address: vera.delov@rwth-aachen.de.
authors.forename: Vera
authors.initials: V
authors.lastname: Delov
authors.affiliation: Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Auf dem Aberg 1, 57392 Schmallenberg, Germany.
authors.forename: Elke
authors.initials: E
authors.lastname: Muth-Köhne
authors.affiliation: Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Auf dem Aberg 1, 57392 Schmallenberg, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Schäfers
authors.affiliation: Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Forckenbeckstr. 6, 52074 Aachen, Germany; Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Auf dem Aberg 1, 57392 Schmallenberg, Germany. Electronic address: martina.fenske@ime.fraunhofer.de.
authors.forename: Martina
authors.initials: M
authors.lastname: Fenske
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D001808:Blood Vessels / Q000187:drug effects*; D005453:Fluorescence; D012680:Sensitivity and Specificity; D018675:Toxicity Tests / Q000379:methods* / Q000592:standards; D014874:Water Pollutants, Chemical / Q000633:toxicity*; D015027:Zebrafish / Q000196:embryology / Q000235:genetics
chemical_list: D014874:Water Pollutants, Chemical
keywords: Fish embryo toxicity test; GFP-fluorescence; Quantifiable endpoint; Transgenic fish; Vasotoxicity; Zebrafish