Perfusable Brain Microvascular Network‐On‐Chip Model to Study Flavivirus NS1‐Induced Endothelial Dysfunction

Abstract Flaviviruses can lead to severe neurotropic‐encephalitic pathology, for which the viral nonstructural protein 1 (NS1) plays a major role. 2D in vitro cellular systems and animal models are currently used to investigate the effects of flavivirus NS1 in the brain‐blood barrier do not fully capture pathogenesis and drug responses seen in humans. Here is reported the development of a perfusable human brain microvascular network‐on‐a‐chip (BMVasChip) model which incorporates brain endothelial cells and pericytes and recapitulates the cellular organization and expression of brain blood barrier‐specific markers, including intracellular junction proteins. This BMVasChip model is used to investigate vasculopathy caused by exposure to a panel of flavivirus NS1 proteins, including Japanese encephalitis (JEV), West Nile (WNV), and dengue virus (DENV) NS1 proteins. The BMVasChip platform is able to demonstrate flavivirus NS1‐induced pathophysiological phenotypes in the BMVasChip, including early and late endothelial activation and dysfunction features such as loss of barrier integrity, morphological features, and production of pro‐inflammatory markers in a virus, dose, and time‐dependent manner. In summary, the BMVasChip model recapitulates key features of endothelial dysfunction, potentially reflecting NS1's role in viral pathogenesis and providing targets for antiviral therapeutics and vaccine development.