New publication: Trilineage differentiation in ReproTracker for accurate teratogenicity assessment

Toxys scientists recently published an article in Frontiers in Toxicology entitled “Implementing a trilineage differentiation in the ReproTracker assay for improved teratogenicity assessment”. This publication not only describes the optimization of ReproTracker to include assessment of neurodevelopmental toxicants and in a higher throughput manner, but also demonstrates the assay’s improved accuracy (86.27%) and sensitivity (87.50%) based on 51 well-known human and animal teratogenic and non-teratogenic compounds. In this blog, we share some highlights from this publication, which can also be accessed in full.

Biology matters

Although in vivo methods remain the golden standard for developmental and reproductive toxicity (DART) testing, they are constrained by multiple limitations such as resource and time inefficiency as well as limited translational value to human biology, and they raise ethical concerns about animal welfare while not fully aligning with the principles of 3Rs. While some existing models already utilize pluripotent or embryonic stem cells, they mainly focus on early germ layer differentiation and do not take later developmental stages into account, although critical biological processes in these stages could be highly susceptible to developmental toxicants.

The ReproTracker assay, also based on human induced-pluripotent stem cells (hiPSCs), incorporates a wider biological coverage of crucial stages for early embryo-development. It follows cell differentiation into meso- and endodermal commitment, leading to the development of cardiomyocytes and hepatocytes. As described in the current study, ReproTracker has now also been optimized to include the ectodermal germ layer, from which neural cells can be developed. This trilineage coverage combined with the inclusion of multiple critical development stages ensures an improved system for developmental toxicity assessment.

Validation with ICH S5 (R3) compounds

The current study demonstrates the applicability of the assay for in vitro developmental toxicity assessment including the trilineage differentiation. The current dataset is comprised of 19 different pharmaceuticals and chemicals based on an internal selection of well-known teratogens and non-teratogens, which had previously been assessed in the ReproTracker assay, as well as the 32 reference compounds listed in the ICH S5 (R3) guidelines. According to this validation study, ReproTracker correctly predicts the developmental toxicity potential of pharmaceuticals with high accuracy (86.27%) and sensitivity (87.50%) at concentrations relevant to human therapeutic Cmax values. The results also describe the correct developmental toxicity prediction of some of the pharmaceuticals solely based on the neural differentiation highlighting, once more, the importance of the biological coverage of NAMs.

Learn more on this topic by reading the full article, visiting ReproTracker assay page, or by contacting us.