Co-expression of ICAM-1, VCAM-1, ELAM-1 and Hsp60 in human arterial and venous endothelial cells in response to cytokines and oxidized low-density lipoproteins

Abstract

T-cells and monocytes are the first cells infiltrating the arterial intima during the early stages of atherogenesis. Recently our laboratory has provided evidence that T-cells isolated from atherosclerotic intima reacts against heat shock protein 60 (Hsp60). Transmigration of activated T-cells into the intima is mediated by adhesion molecules (ICAM-1; VCAM-1; ELAM-1) expressed on activated endothelial cells. Here we studied the potential of cytokines (TNF-alpha, IFN-gamma, IL-1). Escherichia coli lipopolysaccharide (LPS), native and oxidized low-density lipoprotein (LDL; oxLDL) and high temperature to induce adhesion molecules as well as Hsp60 and Hsp70 expression in human endothelial cells (EC). On Northern blots, a strong signal for ICAM-1, VCAM-1 and ELAM-1 was detected after 4 h, which thereafter declined, but did not reach the basal level of untreated control cells. Heat shock induced the expression of Hsp60 and Hsp70 but not of adhesion molecules. EC were cultivated in serum-free medium, which led to the expression of adhesion molecule transcripts. Addition of LDL or oxLDL to these ECs did not alter the expression of these transcripts. The production of adhesion molecule proteins was analysed by flow cytometry. In human venous endothelial cells (HVEC) and human arterial endothelial cells (HAEC) ICAM-1 and VCAM-1 production was permanently highly induced, whereas the high level of ELAM-1 production at 4 h disappeared after 24 h. Furthermore, only HAEC, but not HVEC, produced ICAM-1, VCAM-1 and ELAM-1 after stress by moderately and highly oxLDL. LDL and oxLDL did not induce the production of Hsp60 and Hsp70. The present study demonstrates the co-expression of Hsp60 and adhesion molecules in arterial and venous EC in response to cytokine and LPS exposure, and that oxLDL is an efficient inducer of adhesion molecules in arterial EC and not in venous EC. These features provide the prerequisites for a cellular immune reaction against Hsp60 expressed by stressed EC in the initial stages of atherosclerosis.

Endothelial Cytotoxicity Mediated by Serum Antibodies to Heat Shock Proteins of Escherichia coli and Chlamydia pneumoniae

“…The endothelium, as a barrier between blood and underlying cells, is subjected to continuous mechanical stress from blood pressure and acute or chronic injury from toxins, such as LPS and importantly oxidized LDL, a known risk factor in atherosclerosis. 23 These stressors and many others, such as cytokines 24 and fever, all induce or augment HSP production by the arterial endothelium to prevent cell damage and maintain homeostasis in the vessel wall. 25 Temperatures of 42°C, as used in our experiments, are indeed encountered in a setting of infection.…”

Fluid Shear Stress Induces Heat Shock Protein 60 Expression in Endothelial Cells In Vitro and In Vivo

“…However, as expected and known from previous studies, static controls were not completely negative for hsp 60 mRNA but showed a baseline expression of hsp 60 mRNA, which was possibly due to the stress of cell culture itself. 37,38 Hsp 60 mRNA levels increased between 1 hour and 8 hours of constant shear stress. Cells in lane C underwent 3 hours of shear stress and were allowed to rest for a further 3 hours before harvesting of the cells.…”

Detection of HSP60 on the membrane surface of stressed human endothelial cells by atomic force and confocal microscopy

“…Human umbilical venous endothelial cells (HUVECs) were isolated as described previously (Amberger et al, 1997). Cells were passaged in 0.2% gelatine-coated polystyrene flasks (BD, France) in endothelial cell basal medium (CC-3121, BioWhittaker) with EGM SingleQuots supplements and growth factors (CC-4133, BioWhittaker) in a humidified atmosphere containing 5% CO 2 at 37°C.…”