In vitro pain assay in cultured human iPSC-derived sensory neurons using MEA system

Abstract

Sensory neurons are pain-related neurons and have a variety of receptors that are activated by chemical, thermal, and mechanical stimuli. We evaluated the physiological responses aginst pain-related molecules and temperature in cultured human induced pluripotent stem cell (hiPSC)-derived sensory neurons using multi-electrode array (MEA) system. Capsaicin, menthol and AIT induced significant changes of the firing rate and concentration-dependent responses. We also found the difference of response speed and duration depending on the type of molecules, and that neurons were classified into 27 patterns based on responses against 3 molecules. Furthermore, temperature elevation increased the number of firings and it showed the largest increase at 43 degrees. Moreover, we also confirmed the expression of Nav1.7, TRPV1, and TRPA1 receptors. These results suggested that electrophysiological measurements in hiPSC-derived sensory neurons using a MEA system may be beneficial for clarifying the functions of human neurons in pain research and for drug screening applications.