FETAX Assay for Evaluation of Developmental Toxicity

Abstract

The frog embryo teratogenesis assay Xenopus (FETAX) test is a development toxicity screening test. Due to the small amount of compound needed and the capability to study organogenesis in a short period of time (96 h), FETAX test constitutes an efficient development toxicity alert test when performed early in drug safety development. The test is conducted on fertilized Xenopus laevis mid-blastula-stage eggs over the organogenesis period. Compound teratogenic potential is determined after analysis of the mortality and malformation observations on larvae. In parallel, FETAX test provides also information concerning embryotoxic effect based on larva length.

Neurotransmitter signaling pathways required for normal development inXenopus laevisembryos: a pharmacological survey screen

“…; Mouche et al. ; Leconte & Mouche, ). This preliminary screen represents the first tier of an inverse drug screen, of the variety described by (Adams & Levin, ), in which drugs are tested in a hierarchical manner according to target specificity, to rapidly bypass large families with no apparent roles and progressively home in on targets with interesting functions.…”

“…Information on involvement of neurotransmitters in pattern formation would not only identify novel components of embryogenesis, but also give important insight into potential new endpoints for teratogenic (embryotoxic) effects of widespread pharmaceuticals (Alwan et al 2007;Louik et al 2007;Colvin et al 2011;Myles et al 2013;Hurault-Delarue et al 2014;Yazdy et al 2014). To begin to identify possible patterning roles for other neurotransmitter families, this study took advantage of compounds developed for neuropharmacological research, and an exploratory drug screen was conducted in the Xenopus laevis embryo, a popular vertebrate model for the study of well-conserved developmental mechanisms (Kaltenbrun et al 2011;King et al 2012;Ori et al 2013;Pratt & Khakhalin, 2013;Schmitt et al 2014), as well as for studies of developmental toxicology (Sunderman et al 1991(Sunderman et al , 1992Fort et al 1992;Mouche et al 2011;Leconte & Mouche, 2013). This preliminary screen represents the first tier of an inverse drug screen, of the variety described by (Adams & Levin, 2006), in which drugs are tested in a hierarchical manner according to target specificity, to rapidly bypass large families with no apparent roles and progressively home in on targets with interesting functions.…”

Biometric data assessment on Xenopus laevis tadpoles

“…While traditional approaches focus only on growth, mortality and qualitative data, 7 our method relies on extensive images enhancement automation and complete this qualitative approach with new biometric criteria, and thus for each suited tadpole. Figure 2D shows some of these measurements: length, perimeter, distance between the eyes (eyes) and the position of the suction cup.…”

“…4 For example, embryotoxic and teratogenic damages on larvae were detected with the FETAX (Frog Embryo Teratogenesis Assay -Xenopus) test developed in Xenopus laevis. [6][7][8] In this regard, this specie appears as a very effective laboratory model for assays to dissect actions of chemical contamination. Indeed, profusion of data is available in cell cycle, embryology and development fields.…”

Comparative Analysis of the Developmental Toxicity in Xenopus laevis and Danio rerio Induced by Al2O3 Nanoparticle Exposure

“…We next calculated the toxicity/teratogenic index (TI) of the Al 2 O 3 NPs. A given chemical is considered to be toxic and a developmental teratogen when TI ≥ 1.2 (Mouche et al 2011). First, we calculated the LC50 (for lethality) and EC50 (for malformation) values for each assay and subsequently calculated TI as the ratio of these.…”