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bioRxiv · 10.1101/2025.08.31.673344

Human microphysiological model of dorsal root ganglion-spinal cord dorsal horn circuitry recapitulates opioid induced effects

Pollard, K. J.·Seipel, F. R.·Iyer, N. R.·Bosak, A.·Ashton, R. S.·Moore, M. J.
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Abstract

Microphysiological systems (MPSs) are engineered, in vitro platforms which have been established as viable alternatives to animal models for pre-clinical research with unique advantages over conventional model systems. Many MPSs utilize 3-dimensional (3D) tissue constructs that enable biomimetic cell-cell interactions, allow for extended culture periods, and provide the time necessary for the emergence of physical and physiological characteristics of more mature tissues. Here, we present a novel MPS using human induced pluripotent stem cell (hiPSC)-derived spinal cord dorsal horn (SCDH) spheroids co-cultured with hiPSC-derived dorsal root ganglion (DRG) sensory spheroids in a microengineered hydrogel system to create a "connectoid" model of afferent pain circuitry. SCDH spheroids were functionally innervated by peripheral sensory neurons, and prolonged maturation of hiPSC-derived SCDH neurons within the connectoid system enabled derivation of crucial late-born cell types unattainable using 2D differentiations. Furthermore, hiPSC-derived SCDH spheroids spontaneously generate rhythmic, complex, synaptically-driven electrophysiological waveforms that are disinhibited by morphine exposure, consistent with spinal mechanisms of opioid-induced pruritus and hypersensitivity. One Sentence SummaryhiPSC-derived afferent sensory circuitry model, with NK1R+ spinal cord dorsal horn neurons, yields electrophysiologically mimetic response to opioids.

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Pollard, K. J., Seipel, F. R., Iyer, N. R., Bosak, A., Ashton, R. S., Moore, M. J.. 2025-09-04. Human microphysiological model of dorsal root ganglion-spinal cord dorsal horn circuitry recapitulates opioid induced effects. https://doi.org/10.1101/2025.08.31.673344

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