The Expression of Tissue Factor and Tissue Factor Pathway Inhibitor in Aortic Smooth Muscle Cells Is Up-regulated in Synthetic Compared to Contractile Phenotype

Abstract

SummaryTissue factor (TF) and its specific inhibitor TF pathway inhibitor (TFPI) are produced by vascular smooth muscle cells (SMCs) in vitro and are increased in vivo in atherosclerotic compared to normal vessels. Besides local regulation of the hemostatic balance, this may be related to non-hemostatic TF/protease dependent functions such as SMC proliferation, adhesion and migration. The aim of the study was to compare the expression of both proteins between the contractile (normal adult) and synthetic (neo-intimal) SMC phenotypes.Primary cultures of SMCs isolated from rat thoracic aorta before and 10 days after balloon injury displayed stable characteristics of the contractile and synthetic phenotype, respectively. Synthetic SMCs expressed more TF mRNA than contractile SMCs, but released excess TF in the conditioned medium, so that the cell-associated TF activity measured by a factor Xa generating assay remained similar in the two subtypes. Accordingly, cell surface thrombogenicity measured under blood flow conditions was also similar. The production and release of functional TFPI was enhanced by a factor 3 to 6 (p < 0.01) in synthetic SMCs.A difference in the quantitative expression of TF and TFPI is a new distinctive feature of SMC phenotypes. Matrix-associated TFPI derived from synthetic SMCs may serve as an anchorage for their migration and regulate protease-activated processes during neo-intima formation.

The Syk‐kinase inhibitor R406 impairs platelet activation and monocyte tissue factor expression triggered by heparin‐PF4 complex directed antibodies

“…The TF activity expressed on the luminal surface of monocytes or PBMCs was measured as described previously [35] with some modifications. After stimulation, cells were washed twice in PBS, centrifuged, adjusted to 5 × 10 4 cells per well and incubated with 50 μL of Tris‐buffered saline (50 m m Tris HCl, 120 m m NaCl, 2.7 m m KCl, pH 7.4) containing 3 mg mL −1 BSA, 10 m m CaCl2, 10 n m FVII and 180 n m FX (final concentrations).…”

Adhesion and Function of Human Endothelial Cells Co-cultured on Smooth Muscle Cells

“…14 Expression is increased after injury to the vessel wall or activation of ECs. In vitro, SMCs 11 and ECs 17 express tissue factor at measurable levels. TF expression within vascular cells is a good indication of the coagulant state of the cells.…”

<i>Salmonella </i>Serovars and Vaccination Effect on the Immune Responses of Male and Female Layers

“…PMN cells can produce ROS in number-and time-dependent manners and through direct interaction with PBMCs (Ghrib et al, 2002). As an important member of innate immunity that eliminates pathogens and present antigens, macrophages are heterogeneous cells that react to multiple signals from the microenvironment to eliminate pathogens and present antigens (Van Ginderachter et al, 2006).…”

“…Antibodies (IgG and IgM) and complement are required for an optimal oxidative burst, phagocytosis, and killing of nontyphoidal Salmonella by peripheral blood cells (neutrophil and monocyte) ( Gondwe et al , 2010 ). PMN cells can produce ROS in number- and time-dependent manners and through direct interaction with PBMCs ( Ghrib et al , 2002 ). As an important member of innate immunity that eliminates pathogens and present antigens, macrophages are heterogeneous cells that react to multiple signals from the microenvironment to eliminate pathogens and present antigens ( Van Ginderachter et al , 2006 ).…”