Human coronavirus OC43 infection in human cerebral organoids: novel insights on pathogenesis and potential...

Since the COVID-19 pandemic, there has been a documented rise in the incidence of neurological manifestations among individuals complicated with encephalitis or myelitis. The spectrum of neurological symptoms associated with HCoVs infections is expanding. However, the infection characteristics and pathogenesis of seasonal HCoVs to the central nervous system remain obscure. No pharmacological agents have demonstrated the capacity to specifically and efficaciously mitigate the neurological symptoms induced by HCoVs infections to date.

We developed human cerebral organoids (HCOs) derived from human induced pluripotent stem cells and established a blood-brain barrier (BBB) HCOs co-culture model. We subjected these models to seasonal human coronavirus (HCoV) infections to investigate the viral characteristics within the central nervous system (CNS). Utilizing RNA sequencing, we conducted a preliminary exploration of the mechanisms underlying virus-induced inflammatory responses in the CNS. Furthermore, we assessed the efficacy of antiviral and anti-inflammatory drugs using the HCO model.

Our results showed that among seasonal coronaviruses, HCoV-OC43 replicates efficiently within the organoids, primarily targeting neurons and astrocytes, and disrupts the barrier function of the BBB. RNA sequencing analysis revealed that HCoV-OC43 infection triggers an inflammatory response through the TNF and NF-κB signaling pathways, leading to cell death, impaired neuronal function, and disrupted interneuron signaling. Interestingly, Bardoxolone methyl (CDDO-Me) demonstrated antiviral effects comparable to remdesivir, reducing both inflammation and cell death.

Conclusively, HCOs infected with HCoV-OC43 offer valuable insights into the pathogenesis of HCoVs in central nervous system (CNS), and might serve as a tool for developing novel therapeutic strategies for HCoVs infections, including COVID-19, especially on exploring treatment candidates.