Endothelial Colony Forming Cells as an Autologous Model to Study Endothelial Dysfunction in Patients with a Bicuspid Aortic Valve

Abstract

Bicuspid aortic valve (BAV), the most common congenital heart defect, is associated with an increased prevalence of aortic dilation, aortic rupture and aortic valve calcification. Endothelial cells (ECs) play a major role in vessel wall integrity. Little is known regarding EC function in BAV patients due to lack of patient derived primary ECs. Endothelial colony forming cells (ECFCs) have been reported to be a valid surrogate model for several cardiovascular pathologies, thereby facilitating an in vitro system to assess patient-specific endothelial dysfunction. Therefore, the aim of this study was to investigate cellular functions in ECFCs isolated from BAV patients. Outgrowth and proliferation of ECFCs from patients with BAV (n = 34) and controls with a tricuspid aortic valve (TAV, n = 10) were determined and related to patient characteristics. Interestingly, we were only able to generate ECFCs from TAV and BAV patients without aortic dilation, and failed to isolate ECFC colonies from patients with a dilated aorta. Analyzing EC function showed that while proliferation, cell size and endothelial-to-mesenchymal transition were similar in TAV and BAV ECFCs, migration and the wound healing capacity of BAV ECFCs is significantly higher compared to TAV ECFCs. Furthermore, calcification is blunted in BAV compared to TAV ECFCs. Our results reveal ECs dysfunction in BAV patients and future research is required to unravel the underlying mechanisms and to further validate ECFCs as a patient-specific in vitro model for BAV.

Bicuspid Aortic Valve and Endothelial Dysfunction: Current Evidence and Potential Therapeutic Targets

“…Recently, evidence of endothelial dysfunction (ED) present in BAV has surfaced ( Vaturi et al, 2011 ; Ali et al, 2014 ; Alegret et al, 2016 ; Gavriliuk et al, 2016 ; Balistreri et al, 2018 ; van de Pol et al, 2019 ). ED stands for the abnormal functioning of the endothelial cells (ECs) that cover the inner surface of blood vessels, the endothelium.…”

“…In this regard, our group discovered circulating endothelial microparticles (EMPs) – which are related to ED present in BAV patients plasma in higher concentrations than TAV, being also associated with aortic dilatation ( Alegret et al, 2016 ). Recent studies have shown impaired functionality or decreased number of endothelial progenitor cells (EPCs) in BAV ( Vaturi et al, 2011 ; van de Pol et al, 2019 ). Specifically, one group studieds functionality of peripheral blood endothelial colony-forming cells (pbECFCs) isolated from BAV patients compared to healthy ones as possible a biomarker ( van de Pol et al, 2019 ).…”

“…Recent studies have shown impaired functionality or decreased number of endothelial progenitor cells (EPCs) in BAV ( Vaturi et al, 2011 ; van de Pol et al, 2019 ). Specifically, one group studieds functionality of peripheral blood endothelial colony-forming cells (pbECFCs) isolated from BAV patients compared to healthy ones as possible a biomarker ( van de Pol et al, 2019 ). They found a decreased migratory capacity in the pbECFCs isolated from BAV patients vs. pbECFCs from healthy controls.…”

“…Therefore, it is hard to deny that ED is probably directly related to BAV and its worse prognosis, especially with aortic dilatation and aortic stenosis ( Vaturi et al, 2011 ; Ali et al, 2014 ; Alegret et al, 2016 ; Gavriliuk et al, 2016 ; Balistreri et al, 2018 ; van de Pol et al, 2019 ). Nevertheless, the pathways that could promote ED and its relevance in BAV are not fully known.…”

Tunable Fibrin-Alginate Interpenetrating Network Hydrogels to Guide Cell Behavior

“…Images were processed and analyzed in ImageJ (NIH, Bethesda, MD). Confocal images were converted to 500 ´ 500 pixel size, converted to binary, and circularity and area of cells, with an area of at least 50 µm 2 , well below the average size of ECFCs [19], were measured.…”