Engineering circuits of human iPSC-derived neurons and rat primary glia

Abstract

Novel in vitro platforms based on human neurons are needed to improve early drug testing and address the stalling drug discovery in neurological disorders. Topologically controlled circuits of human induced pluripotent stem cell (iPSC)-derived neurons have the potential to become such a testing system. In this work, we build in vitro co-cultured circuits of human iPSC-derived neurons and rat primary glial cells using microfabricated polydimethylsiloxane (PDMS) structures on microelectrode arrays (MEAs). Such circuits are created by seeding either dissociated cells or pre-aggregated spheroids at different neuron-to-glia ratios. Furthermore, an antifouling coating is developed to prevent axonal overgrowth in undesired locations of the microstructure. We assess the electrophysiological properties of different types of circuits over more than 50 days, including their stimulation-induced neural activity. Finally, we demonstrate the effect of magnesium chloride on the electrical activity of our iPSC circuits as a proof-of-concept for screening of neuroactive compounds.

A modular and flexible open source cell incubator system for mobile and stationary use

“…The field of bottom-up neuroscience[10] has profited from the ever-increasing quality of new 3D printing and microfluidic tools. By now such devices can be used to control axonal growth with high fidelity in neuronal cultures [11, 12] even with highly sensitive cells such as human-induced pluripotent stem cell (hiPSC)-derived neurons [13, 14]. While these approaches introduce a high level of control to the cultures themselves, such control is only useful, if interaction with such cell cultures occurs in a reliable fashion for extended periods of time.…”

Investigation of the Input-Output Relationship of Engineered Neural Networks Using High-Density Microelectrode Arrays

“…The guidance of axons within microstructures is based on the axonal edge guidance phenomenon (Renault et al, 2016). Using polydimethylsiloxane (PDMS) microstructures it was previously shown that engineered neural networks could be established on standard, low-density glass-based MEAs using both primary rat neurons (Ihle et al, 2022;Forró et al, 2018;Mateus et al, 2022) as well as hiPSC-derived neurons (Girardin et al, 2022a(Girardin et al, , 2022b. More recently, we have transferred this 'bottom-up' neuroscience technique to complementary metal-oxide-semiconductor (CMOS)-based MEAs, which offer electrode densities orders of magnitude larger than in conventional passive MEAs and reveal the propagation of spontaneous activity in such small, confined neural networks with high spatiotemporal resolution (Duru et al, 2022).…”