Engineering FlowGERO-Chips: Complex flow-enabled long-term multicellular blood vessel-chips for enabling geroscience

About This Grant

Engineering FlowGERO-Chips: Flow reversal-enabled long-term vessel-chips for modeling geroscience Age is a major risk factor for cardiovascular disease (CVD) where a significant contributor to vascular dysfunction is the age-associated impairment of arterial hemodynamics, specifically adverse retrograde or oscillatory blood flow, known as flow reversal. Current preclinical in vitro models, such as microphysiological systems incorporating cells from Hutchinson-Gilford Progeria Syndrome (HGPS) patients, have some limitations because they represent a pathological state from the initial time, often cannot form a fully confluent lumen, and typically remain stable for only a few days, thus failing to capture the progressive dynamics of aging. To overcome these limitations, we propose the development of FlowGERO-Chips, a New Approach Method (NAM) designed to replicate human aged arteriolar blood vessels and assess treatments relevant to geroscience. The FlowGERO- Chip is innovative in three key ways: it utilizes normal induced pluripotent stem cell (iPSC)-derived endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) in a multicellular architecture; it is stable and supports long-term (up to 90-day) culture; and it enables the time-dependent assessment of EC-VSMC crosstalk under clinically-relevant flow reversal conditions. For Aim 1, we will engineer the FlowGERO-Chip with a cylindrical lumen of iPSC-ECs surrounded by extracellular matrix-embedded iPSC-VSMCs, mimicking in vivo vessel structure. Using the custom-engineered Hemadyne perfusion system, which can accurately reproduce pathological flow reversal waveforms, we will expose the chips to normal versus reversed arterial periodic flow for up to 90 days. We anticipate that flow reversal will accelerate a shift towards a senescent phenotype, characterized by increases in senescence associated biomarkers. For Aim 2, we will validate the FlowGERO- Chips by administering a telomerase (hTERT) mRNA therapy, which has been shown to reverse vascular senescence in vivo, either alone or in combination with the senolytic cocktail Dasatinib + Quercetin. We will monitor longitudinal changes in senescence-associated secretory phenotype (SASP) markers, expecting that these interventions will reverse or delay the EC and VSMC senescence induced by reversed/retrograde flow waveforms and extend the viability of the chip. In summary, this platform will provide a robust tool for predictive studies and preclinical drug discovery related to cardiovascular aging.