Abstract: Microphysiological system (MPS) is an in vitro culture technology that　reproduces the physiological microenvironment and functionality of humans, and is expected to be applied for drug screening. In this study, a novel MPS device was constructed on MEA chips for compartmentalized co-culture of different types of neurons, and we successfully detected electrophysiological activities in two types of in vitro peripheral model (i.e., neuromuscular junction (NMJ) model, and pain model) before and after drug administration. The MPS device was combined to MEA surface using a directly photobonding method to avoid cell damage during culturing. Human iPSC-derived motor neurons and human primary skeletal muscles were cultured in different chambers linked by microfluidics. Spontaneous activity could be detected from both cells. Notably, after electrical stimulation in motor neurons, a corresponding evoked response could be measured in the neighbor skeletal muscle, which indicated the formation of NMJ in the model. By using motor neurons derived from ALS patients, an increasing in spontaneous activity (hyperexcitation) was measured compared to healthy motor neurons. And such hyperexcitation was reduced after Rapamycin treatment. Next, human iPSC-derived sensory neurons and human iPSC-derived spinal cord dorsal horn (SCDH) were cultured in different chamber to mimic pain circuit. After adding a TRPA1 agonist AITC to sensory neurons, an acute increasing in spontaneous activity could be measured followed by a slowly increasing in SCDH later. Interestingly, the SCDH activity maintained even when the activity in sensory neuron temporary dropout. In contrast, administration of CNQX in SCDH could induce an acute increasing of activity, which might be through GABA receptors in interneurons. And spike disappearance was detected in sensory neurons later, which indicated the signal transduction between different neurons through synaptic networks. Taken together, the present compartmentalized MPS device enables co-culture of different types of peripheral neurons with axonal network linkage, which is essential to reproduce the relevant human anatomical architecture and for drug assessments by MEA measurement.
