Endothelium specific Weibel-Palade bodies in a continuous human cell line, EA.hy926

Abstract

Weibel-Palade bodies are ultrastructurally defined organelles found only in vascular endothelial cells. Because endothelium in corpo is very dispersed, isolation and further characterization of this organelle has been dependent on increasing the number of cells in culture. However, primary isolates of endothelial cells have a limited replication potential and tend to senesce in culture. In this report, EA.hy926, a continuously replicating cell line derived from human endothelium, is shown to contain Weibel-Palade bodies. Electron micrographs demonstrate the ultrastructural characteristics of these tissue-specific organelles and their cytoplasmic distribution in EA.hy926 cells. Von Willebrand factor, which has been shown to exist in Weibel Palade bodies, is demonstrated by immunofluorescence in discrete rod-shaped organelles whose size, shape, and distribution are consistent with that of Weibel-Palade bodies in primary endothelial cell cultures. Rapid release of von Willebrand factor can be induced by calcium ionophore, and large multimeric forms of the protein are found in EA.hy926 cells. These two properties are consistent with the function currently ascribed to Weibel Palade bodies: storage of multimerized von Willebrand factor. Thus ultrastructural, immunologic, and functional data establish the existence of this as yet poorly understood tissue-specific organelle in a continuous, vigorously replicating human cell line.

Plasma sodium stiffens vascular endothelium and reduces nitric oxide release

“…Human endothelial cells [EA.hy926 (43)] were grown in culture as described (44). Chemicals were added to the medium as appropriate.…”

The Borrelia burgdorferi Integrin Ligand P66 Affects Gene Expression by Human Cells in Culture

“…The medium for the 293ϩ␣ v ␤ 3 cells was also supplemented with 400 ng/ml G418 (Sigma). The human macrovascular endothelial cell line EA.hy926 (17,18) was grown in monolayers at 37°C under 5% CO 2 in DMEM with 4.5 g/liter glucose, supplemented with 10% FBS and hypoxanthine-aminopterin-thymidine (HAT) (Sigma) to final concentrations of 100 M hypoxanthine, 0.4 M aminopterin, and 16 M thymidine, and with 2 mM L-glutamine, 100 units/ml penicillin, and 100 g/ml streptomycin. Each of these cell lines has previously been shown to bind Borrelia burgdorferi (13,28), with different host cell substrates contributing to B. burgdorferi attachment.…”

Examination of the mechanism by which heparin antagonizes activation of a model endothelium by interferon-gamma (IFN-γ)

“…The EAhy.926 hybridoma was formed by fusion between human umbilical vein endothelial cells (HUVEC) and the human type II pneumocyte-like carcinoma cell line A549 [23], and shares many features of normal vascular endothelial cells, including fibrinolytic properties and expression of factor VIII, von Willebrand factor, Weibel-Palade bodies and prostacyclin [24]. EAhy.926 cells have been used previously to model both leucocyte adhesion [25] and antigen presentation [26] functions of endothelial cells.…”