Brigid 

Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL) is an under-researched hereditary small-vessel disease in humans caused by a mutation in the NOTCH3 gene. This gene encodes for a receptor protein critical for maintaining the structural integrity of small blood vessels in the human brain. The Elahi Lab aims to investigate how TNF-α, a pro-inflammatory cytokine, influences CD31 expression. CD31 is a marker of proper endothelial functioning in induced endothelial cells (iECs). To address this, we analyzed both healthy and CADASIL-derived iECs and mural cells (iMCs). Understanding how inflammatory signals alter endothelial behavior may clarify mechanisms of vascular dysfunction in CADASIL. This research investigates how TNF-α affects endothelial cell function in CADASIL, with the hypothesis that inflammatory signalling will alter CD31 expression more significantly in the CADASIL-derived cells. To conduct the study, the Elahi Lab first collected blood from participants and generated patient-specific induced Pluripotent Stem Cells (iPSCs), which were then differentiated into iECs and iMCs. Then, immunostaining was performed to visualize protein expression in these cells. Next, an adhesion assay was carried out, which treated the cells with TNF-α. Lastly, imaging and quantifying CD31 signal intensity were performed. The results demonstrated a relationship between TNF-α exposure and increased CD31 intensity, particularly in co-cultures of iECs and iMCs. TNF-α-treated co-culture dishes showed higher CD31 levels compared to iEC-alone conditions. These findings highlight the importance of physiologically accurate co-culture conditions for modelling CADASIL, and may inform the development of targeted therapeutics. More broadly, this work contributes to the Elahi Lab’s long-term goal of building in vitro models of the Blood-Brain Barrier (BBB) to study vascular pathology, as successfully recapitulating diseased iECs and iMCs represents a critical step toward that system.