USE OF 3D NEURONAL CELL MODELS FOR PHARMACOLOGICAL STUDIES IN EPILEPSY

Epilepsy is one of the most common neurological disorders, affecting approximately 1% of the population worldwide, with about one-third of patients facing drug-resistant epilepsy, which highlights the urgent need for new and effective treatment strategies. As regulatory agencies such as the FDA and EMA encourage the use of non-animal methodologies human induced pluripotent stem cell (iPSC)-derived 3D neuronal models come into focus. The aim of this study was to establish human iPSC-derived spheroids as a platform for pharmacological studies of antiepileptic drugs using calcium imaging and multi electrode arrays (MEA). The human iPSC-derived neuronal spheroids used in this study consisted of 10% astrocytes and 90% neurons, with the neuronal population comprising roughly 80% glutamatergic- and 20% GABAergic neurons and were cultured for at least 21 days. For calcium imaging spheroids were stained with Calcium 6 dye for 2 hours before being recorded on an inverted microscope. For MEA recordings, spheroids were positioned in our proprietary SphereChip designed to maintain stable contact between the spheroid and electrode surface. Epileptiform bursting was induced by 4-aminopyridine and the ability of various reference compounds like XEN1101 and ML-213 co-applied with 4-aminopyridin to suppress this activity at increasing concentrations was assessed. MEA recordings demonstrated a reduction in spiking and bursting of neuronal spheroids by reference compounds, while calcium imaging showed a reduction in bursting. In conclusion, these findings support that 3D neuronal spheroids represent a robust and promising model system for the pharmacological evaluation of antiepileptic drugs.