Currently existing biological testing strategies still involve an extensive animal experimentation in vertebrate models, which is expensive and is associated with a number of important ethical concerns and regulatory constraints. The alternative methods to animal testing are typically based on cellular models. The main limitation of these in vitro techniques is that they cannot predict complex responses at the level of an organism, usually involving a multi-organ crosstalk. Caenorhabditis elegans (C. elegans) has been known for more than 60 years as a powerful model organism in fundamental research, allowing exploration of different facets of aging, development, neurosciences and genomics. This nematode gained popularity amongst the scientific community due to its small size, short life cycle, ease of cultivation and propagation and a powerful genetic toolkit. Despite their relative simplicity, nematodes present a wide range of behaviors and possess well-defined tissues. Nowadays C. elegans starts to get recognition as a valuable alternative for rodent and cell models in predictive toxicology studies. However, experimentation in C. elegans is still mainly based on manual labor and requires a specific skill-set from the person manipulating the worms. These testing strategies relying on manual handling techniques and direct observation by the operator hence lack reproducibility and standardization, overall largely limiting the potential of the worms for high-throughput and high-content screenings required for toxicology studies.
Results
Using this platform, we successfully executed different types of toxicological studies in C. elegans, including the assessments of reproductive toxicity, developmental toxicity, acute toxicity and embryotoxicity. Moreover, we applied these new test methods to the characterization and safety assessment of different classes of substances, comprising small molecules, nanoparticles, anthelmintics or food additives in worms. Finally, the possibility of performing fluorescent imaging permited to profit from the large existing collection of C. elegans reporter strains: in this manner a user can collect additional information on the underlying molecular mechanisms by monitoring the actors of different stress pathways.