(1351-D) Neurotoxicity and Drug Screening Assay Characterization in Healthy and Progranulin R493X HZ KO Human iPSC-derived Induced Excitatory Neurons
Tuesday, February 6, 2024
2:00 PM – 3:00 PM EST
Location: Exhibit Halls AB
Abstract: Neurogenin-2 (NGN2) forward programming of human induced pluripotent stem cells (iPSCs) offers a robust method for generating scalable quantities of neurons with low lot-to-lot variability. Using this methodology, we generated highly pure excitatory glutamatergic neurons (iCell Induced Excitatory Neurons) at commercial scale from iPSC lines with an apparently healthy normal (AHN) background or a heterozygous (HZ) and pathogenic R493X nonsense mutation in the progranulin gene (GRN) to model frontotemporal dementia (FTD). These induced cells are highly pure neurons (>90% βIII-Tubulin-positive) and express excitatory glutamatergic genes, including vesicular glutamate transporters (VGLUT) and AMPA receptor subunits (GRIA). We verified that these characteristic markers are expressed consistently across lots and confirmed that a reduction in granulin monomers in the GRN R493X cell line was observed. In the current study, we evaluated the suitability of these induced excitatory neurons for high-throughput neurotoxicity and drug screening experiments, including neurite outgrowth (Incucyte), multielectrode array (MEA), calcium imaging, and cell survival assays. Within each assay we established a baseline comparison between the AHN and GRN R493X HZ KO induced excitatory neurons to identify and characterize differences in phenotypes. Notably, differences in MEA activity development were detected, with GRN R493X HZ KO displaying aberrant network synchrony compared to AHN neurons. These baseline metrics of survival, neurite outgrowth, and activity were then challenged via treatment with a panel of neurotoxic compounds or chemotherapeutic agents to determine dose responses across high throughput assays. These studies demonstrate the high-throughput utility and biological relevance of induced excitatory neurons across numerous neurotoxicity assays, suggesting these cells offer a platform for early drug screening and disease modeling.