HIV-1 Tat protein exposure alters the morphological characteristics and gene expression in the primary mouse cortex endothelial cells and human brain microvascular endothelial cells

HIV-1-associated neurocognitive disorders (HAND) are highly prevalent in the era of combination of antiretroviral therapies. Recent studies suggest that damage of blood-brain barrier (BBB) may serve as an early biomarker of cognitive dysfunction in people living with HIV. In this study, we focused on endothelial cells, the core component of the BBB, to investigate the effects of HIV-1 transactivator of transcription (Tat) protein on their morphological alterations and gene expression profiles of human brain microvascular endothelial cells (HBMVECs). Our results demonstrated that Tat-exposed HBMVECs showed reduced CD31 expression, increased phalloidin staining intensity, and activation of inflammatory response pathways as revealed by RNA-seq analysis. Overall design: HBMVECs grew to 80-90% confluence on 24-well plates which then were seeded at a density of 10,000 cells/well in 96-well plates. The cells were exposed to control medium containing 0.1% protease inhibitor cocktail for preventing Tat protein degradation or the same medium containing recombinant Tat1-86 or heated Tat (95°C for 5 min) at a 12.5 nM final concentration and incubated at 37°C, 5% CO2 incubator. Eight hours after Tat treatment, cells were harvested for RNA isolation.