Tissue factor expression by a human kidney proximal tubular cell line in vitro: a model relevant to urinary tissue factor secretion in disease?

Abstract

Aim: To study baseline and stimulated tissue factor (TF) production from a normal, albeit immortalised, human kidney proximal tubular cell line (HKC-5), in order to establish a model for investigating the role of inflammatory mediators in the increased urinary TF (uTF) seen in inflammatory and neoplastic disease. Methods: TF procoagulant activity, expression and secretion in HKC-5 cells were investigated using TF activity and antigen assays, fluorescence confocal microscopy and immunocytochemistry. TF expression in the HKC-5 cells was also studied using reverse transcription (RT)-PCR and its synthesis was suppressed using antisense oligodeoxynucleotide (ODN), directed against human TF mRNA. Cells were stimulated, after serum deprivation, with bacterial lipopolysaccharide (LPS), an agonist known to enhance TF expression in monocytes. They were also subject to serum starvation. Results: Analysis by RT-PCR showed TF production by stimulated and actively metabolising HKC-5 cells. Antisense ODN treatment resulted in approximately 50% suppression of TF synthesis compared to a mismatch ODN. The amount of TF produced by the HKC-5 cells was time dependent and coincides with a decrease in the intracellular TF levels. LPS up-regulated TF production in HKC-5 cells. Reducing fetal calf serum concentrations in the culture medium decreased TF production and secretion. Conclusion: Stimulated TF synthesis and secretion in vitro by HKC-5 cells is consistent with the hypothesis that uTF is produced by tubular cells influenced by mediators of disease states and provides a model for further mechanistic investigations.

PAR2 Activation on Human Kidney Tubular Epithelial Cells Induces Tissue Factor Synthesis, That Enhances Blood Clotting

“…In normal human kidney tissue, immunohistochemistry has been used to identify TF expression in parietal and visceral epithelia of Bowman’s capsule and also in the tubular epithelium in animal models of kidney disease ( Flössel et al, 1994 ; Wendt et al, 1995 ; Erlich et al, 1999 ). TF is constitutively expressed by tubular cell lines HKC-5, HK2 and primary kidney epithelial cells in vitro ( Sugawara et al, 2003 ; Nestoridi et al, 2005 ; Lwaleed et al, 2007 ). The HTEC cultures used in the present study also constitutively expressed TF, although at relatively low levels.…”

“…The constitutive expression of TF is a common feature of cells resident in highly vascularized organs, which are not normally exposed to blood ( Drake et al, 1989 ; Parry et al, 1998 ; Ettelaie et al, 2016 ). This enables an almost instantaneous clotting event if the vasculature of an organ is compromised and provides additional hemostatic protection to that organ ( Nestoridi et al, 2005 ; Lwaleed et al, 2007 ).…”

Urinary extracellular vesicles carry multiple activators and regulators of coagulation

“…Frontiers in Cell and Developmental Biology frontiersin.org 1986). The origin of urinary TF is likely tubular cells (Lwaleed et al, 2007), supported by clinical and biochemical evidence (Lwaleed et al, 1999). In the literature the effects of urine on coagulation system are largely attributed to vesicle-associated TF (Kurosawa et al, 1984).…”

Tissue Factor, Thrombosis, and Chronic Kidney Disease

“…Renal tubular cells also express TF, and the expression has been reported to be upregulated in models of unilateral ureteral obstruction and cisplatin-induced nephrotoxicity [ 34 , 35 ]. In vitro studies, various stimuli, including lipopolysaccharide, high glucose, and agonists of PARs, induce TF expression in renal tubular cells [ 36 , 37 , 38 ].…”