30-24 – Investigating direct and indirect effects of viral infections on the brain and prevention via immune suppression.

Viral infections can cause severe neurological complications. Understanding how viruses affect the central nervous system (CNS) is crucial for developing new treatments. Viruses may directly infect the CNS due to blood-brain barrier (BBB) damage or indirectly by triggering an immune response. Herpes simplex virus 1 (HSV-1) and Varicella zoster virus (VZV) are common viruses that can cause damage to the BBB. This project aims to develop a novel “brain-on-a-chip” model using microfluidic chips to co-culture endothelial cells and astrocytes. Using Synvivo BBB chips and a Harvard Bioscience PHD ultra-pump, we replicate an in vivo-like shear flow that is not possible with other in vitro models like Transwell®. Electrodes are used to measure transendothelial electrical resistance (TEER), and the use of fluorescently labelled antibodies show the expression of tight junctions (e.g., ZO-1) and other cell markers of interest (e.g., GFAP, CD31). We established a co-culture of human primary astrocyte and human cerebral microvascular endothelial cells in different compartments of the microfluidic chip. Confocal microscopy showed expression of key proteins: the tight junction protein, ZO-1, and astrocyte marker glial fibrillary acidic protein (GFAP). Transendothelial electrical resistance measurements were used to assess the integrity of the endothelial monolayer from cell seeding to integral barrier formation, aiding future timepoint analysis post-virus infection. Planned future work includes: infecting the co-culture with HSV-1 and VZV, measuring TEER changes over time, and an imaging time course. Supernatant analysis via ELSIA at each timepoint will reveal changes in the chemoattractant profile, identifying key targets for immune suppression. These targets will then be inhibited to see if blocking their expression protects barrier integrity. Developing an in vitro shear flow BBB co-culture model will help to understand infection pathways leading to neurological complications.