Surface coating biomaterials shape morphology, transcriptomic identity, and excitability of human iPSC-derived nociceptors

Abstract Human induced pluripotent stem cell (iPSC)-derived nociceptors (iNocs) are valuable tools for modelling sensory neurobiology and pain, while achieving maturation and reproducibility remains challenging. Currently available differentiation protocols focus on soluble factors, but the role of the extracellular matrix is insufficiently understood. In this study we investigated how widely used plastic surface coatings including laminin, poly-L-lysine/laminin and Matrigel ™ influenced the morphology, transcriptional identity, and functional activity of human iNocs combining indirect immune fluorescence microscopy, RNA sequencing, multi-electrode array recordings and single-cell patch-clamp techniques. Significant differences were obtained in iNocs morphology, the size of cellular clusters, and transcriptomic signatures. Matrigel coating promoted biological gene ontologies related to “extracellular matrix remodelling” and “mesenchymal pathways” whereas laminin coating enhanced neuronal and synaptic processes and enriched proliferative gene sets. Spontaneous discharge activity was increased in iNocs cultured on poly-L-lysine/laminin exhibiting the highest firing rates. Single cell patch clamp recordings revealed minor effects of coating materials on passive membrane properties and basic electrophysiological parameters of individual iNocs. These findings introduce coating specific extracellular matrix compositions as a critical regulator of iNoc phenotypes. Optimizing surface coating substrates offers a powerful strategy to improve the physiological relevance and maturation of translational human pain models.