Morphology and vasoactive hormone profiles from endothelial cells derived from stem cells of different sources

Abstract

Endothelial cells form a highly specialised lining of all blood vessels where they provide an anti-thrombotic surface on the luminal side and protect the underlying vascular smooth muscle on the abluminal side. Specialised functions of endothelial cells include their unique ability to release vasoactive hormones and to morphologically adapt to complex shear stress. Stem cell derived-endothelial cells have a growing number of applications and will be critical in any organ regeneration programme. Generally endothelial cells are identified in stem cell studies by well-recognised markers such as CD31. However, the ability of stem cell-derived endothelial cells to release vasoactive hormones and align with shear stress has not been studied extensively. With this in mind, we have compared directly the ability of endothelial cells derived from a range of stem cell sources, including embryonic stem cells (hESC-EC) and adult progenitors in blood (blood out growth endothelial cells, BOEC) with those cultured from mature vessels, to release the vasoconstrictor peptide endothelin (ET)-1, the cardioprotective hormone prostacyclin, and to respond morphologically to conditions of complex shear stress. All endothelial cell types, except hESC-EC, released high and comparable levels of ET-1 and prostacyclin. Under static culture conditions all endothelial cell types, except for hESC-EC, had the typical cobblestone morphology whilst hESC-EC had an elongated phenotype. When cells were grown under shear stress endothelial cells from vessels (human aorta) or BOEC elongated and aligned in the direction of shear. By contrast hESC-EC did not align in the direction of shear stress. These observations show key differences in endothelial cells derived from embryonic stem cells versus those from blood progenitor cells, and that BOEC are more similar than hESC-EC to endothelial cells from vessels. This may be advantageous in some settings particularly where an in vitro test bed is required. However, for other applications, because of low ET-1 release hESC-EC may prove to be protected from vascular inflammation.

An autologous endothelial cell:peripheral blood mononuclear cell assay that detects cytokine storm responses to biologics

“…As shown previously (19,20), endothelial cells grown out from human blood (BOECs) of healthy volunteers had typical endothelial cell morphology and expressed VEcadherin ( Fig. 1 and Table 1).…”

A bioassay system of autologous human endothelial, smooth muscle cells, and leukocytes for use in drug discovery, phenotyping, and tissue engineering

“…22 Indeed, the release of high levels of ET-1 is a unique defining feature of endothelial cells. 22 Indeed, the release of high levels of ET-1 is a unique defining feature of endothelial cells.…”

“…In culture, endothelial cells from all origins, including BOECs, release high levels (relative to other cell types) of ET-1. 22 Indeed, the release of high levels of ET-1 is a unique defining feature of endothelial cells. As expected, therefore, the BOECs used in our coculture model (Figure 2A) released high levels of ET-1 ( Figure 2B).…”

Bridging the gap: induced pluripotent stem cell derived endothelial cells for 3D vascular assembly

“…A number of studies have demonstrated the differentiation of hPSCs into ECs [13][14][15][16][17][18][19][20][21][22][23][24]. Several different differentiation approaches have been utilized, all novel in their methodology but with a similar end goal: acquiring functional ECs.…”