Non-polio enterovirus infection and electrophysiological changes in human iPSC-derived neural networks.

BACKGROUND: The non-polio enteroviruses (NPEV) enterovirus D68 (EV-D68) and enterovirus A71 (EV-A71) are highly prevalent and considered pathogens of increasing health concern due to their neurotropic potential. Severe neurological complications of usually mild and self-limiting NPEV infections include meningitis, encephalitis, and acute flaccid paralysis, especially in children and immunocompromised patients. Despite clinical burden, the underlying neuropathogenesis of EV-D68 and EV-A71 remains poorly understood. In particular, the impact of the infection on neural function has not been clearly elucidated. METHODS: We investigate the replication kinetics, cellular tropism, pro-inflammatory cytokine responses, and electrophysiological effects of EV-D68 and EV-A71 infection in a physiologically relevant human pluripotent stem cell-derived neural co-culture model, consisting of excitatory neurons and astrocytes using a micro-electrode array platform. FINDINGS: All NPEV replicated efficiently in the neural co-cultures and infection was detected in both neurons and astrocytes. Both EV-D68 and EV-A71 infection resulted in decreased neural activity in the co-cultures, with the EV-D68 clade A2/2018 inducing the most rapid and robust negative effect on neural co-cultures, followed by EV-D68 clade B3/2019. Despite the lack of release of infectious virus particles of EV-D68 B3/2019 in the supernatant, the infection could spread in the cultures and reduce neurotransmission. Higher viral load of EV-A71 did not result in enhanced impairment of neural function. INTERPRETATION: Our results demonstrate that neurotropic NPEVs lead to disruption of spontaneous neural activity in a virus-specific manner, which does not correlate with their replication efficiency. FUNDING: The Netherlands Organisation for Health Research, Development and the Dutch Research Council, the Netherlands Organ-on-Chip Initiative.