Topographical guidance of PSC-derived cortical neurons

Abstract

Background and Aims: Human pluripotent stem cell- (PSC-) derived neurons are increasingly used in the study of neurodevelopmental and neurodegenerative diseases. Electrophysiological activity is a crucial and defining function of these neurons. Patch clamping and the more recently developed multielectrode arrays are used to evaluate this complex function. In this study, we assess the effect of topography on PSC-derived neurons as a baseline for the development of next-generation silicon oxide substrates (in direct relation to MEA fabrication) that integrate topography as a means to guide network formation and stimulate differentiation. Methods: Human PSC was differentiated towards cortical neurons and seeded on a silicon micropatterned substrate to screen for topographic guidance and improved neurite outgrowth. We next developed customized micropillar and microgroove substrates to further assess the effect of topography on human cortical neurons. Immunocytochemistry and morphological analyses were used to track neuron differentiation and guidance. Results: Microgroove and micropillar substrates appeared to support the differentiation of human stem cell-derived cortical neurons, promoted neurite outgrowth, and facilitated contact guidance. In contrast to flat surfaces, topography also appeared to limit the number of NESTIN positive neuronal progenitor cells present in the culture. Conclusion: We describe the topographical preferences of human PSC-derived cortical neurons, on neurite outgrowth and guidance. Embedding topography in silicon substrates may be an effective approach to direct and improve neuronal network formation. We propose to integrate topography in multielectrode arrays as a practical method to shape the neuro-electronic interface.