Patient-Derived Induced Pluripotent Stem Cell Models for Drug Identification in SCN2A-Related Epilepsy

Abstract

SCN2A-related epilepsy is a severe neurological disorder caused by mutations in the SCN2A gene, which encodes NaV1.2 voltage-gated sodium channels. These mutations lead to neuronal hyperexcitability, resulting in diverse neurodevelopmental disorders such as epilepsy, intellectual disabilities, and autism spectrum disorders. Due to the variability in clinical symptoms, understanding the pathological mechanisms of SCN2A-related epilepsy is critical for developing targeted therapies. In this study, patient-derived induced pluripotent stem cells (iPSCs) were generated from peripheral blood mononuclear cells (PBMCs) to model SCN2A-related epilepsy and investigate its cellular and molecular characteristics. Using CRISPR/Cas9 gene-editing technology, SCN2A mutations were corrected, enabling direct comparisons of physiological and molecular properties between mutated and corrected neurons. Electrophysiological analyses, including micro-electrode array (MEA) recordings, revealed that SCN2A mutations significantly increased neuronal firing rates and caused disruptions in network synchronization, which are key contributors to hyperexcitability. To identify potential therapeutic interventions, high-throughput drug screening was performed on patient-specific neurons, focusing on sodium channel blockers. Among the tested compounds, phenytoin, a widely used sodium channel blocker, validated the experimental model by demonstrating dose-dependent reductions in hyperexcitability. Additionally, five candidate compounds were evaluated, with several exhibiting enhanced efficacy at lower concentrations compared to phenytoin. This study presents a robust platform for modeling SCN2A-related epilepsy, integrating patient-derived iPSC models, CRISPR/Cas9 gene editing, and advanced electrophysiological techniques. By combining high-throughput drug screening with computational drug discovery approaches, the research highlights promising pathways for personalized treatments targeting the specific molecular mechanisms of SCN2A mutations. These findings provide critical insights into the pathophysiology of SCN2A-related epilepsy and pave the way for future validation of these compounds in preclinical and clinical settings, advancing the development of precision medicine for drug-resistant epilepsy.