Advancing antiviral research for West Nile Virus using novel 2D and 3D neural cell cultures
Résumé
West Nile Virus (WNV), a member of the Orthoflavivirus family, is an arbovirus that causes severe neurological disorders in humans and horses, with no antiviral treatment available. Antiviral research against this virus has mostly been conducted in cell lines, often not representative of WNV’s natural tropism. In this study, we developed and characterized cellular models representative of WNV infection of the human and equine central nervous system to better understand the pathophysiology of this virus and to identify antiviral molecules with a high predictive value of their efficacy in vivo. Thus, we infected various human and equine neural cells in 2D/3D cultures: human neuronal/glial cells derived from fetal neural progenitors, human spinal motoneurons and human or equine brain organoids derived from induced pluripotent stem cells. Viral replication, tropism and cellular impact were assessed in each model through immunofluorescence assay and quantification of infectious viral particles (TCID50). Our results showed that WNV replicated in all 4 models but with significant variations between cell subtypes. In particular, a difference of viral tropism between neuronal subtypes has been demonstrated. In 2D models, WNV induced both direct and indirect death of neurons and astrocytes. Using these models, we tested the antiviral and neuroprotective effects of several compounds. Notably, two nucleoside analogs demonstrated dose-dependent activity against WNV in equine or human models. This study successfully developed physiologically relevant 2D and 3D cell models for studying WNV and identifying promising antiviral molecules.