Further insight into the heparin-releasable and glycosylphosphatidylinositol-lipid--anchored forms of tissue factor pathway inhibitor.
The release of tissue factor pathway inhibitor (TFPI) from human umbilical vein endothelial cells (HUVECs) was investigated using heparin and phospholipase C. The experiment included incubating HUVECs with 0, 1, or 10 U/mL heparin diluted in Dulbecco Modified Eagle's Medium plus 5% fetal calf serum for 1 or 24 hours. A statistically significant increase in TFPI activity levels was seen at 1 hour, but not at 24 hours. A 20-fold increase in the release of TFPI after phospholipase C treatment of HUVECs was demonstrated, confirming that it is glycosylphosphatidylinositol-lipid (GPI) anchored. Sequential treatment of HUVECs with phospholipase C and heparin was performed, and a trend was observed where GPI-anchored TFPI levels were increased after 1 hour of pretreatment with heparin but were decreased after 24 hours. Serum is a requirement for the heparin-dependent release of TFPI from HUVECs. Heparin pretreatment of HUVECs may affect levels of GPI anchored TFPI in a time and dose-dependent manner.
Ellery
Paul E R
PE
Western Australia Biomedical Research Institute, Curtin University of Technology, Perth, Western Australia.
Hardy
Kathy
K
Oostryck
Robert
R
Adams
Murray J
MJ
D002478:Cells, Cultured; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism; D017261:Glycosylphosphatidylinositols / Q000378:metabolism*; D006493:Heparin / Q000494:pharmacology*; D006801:Humans; D008074:Lipoproteins / Q000378:metabolism*; D020033:Protein Isoforms / Q000378:metabolism; D010738:Type C Phospholipases / Q000494:pharmacology
D017261:Glycosylphosphatidylinositols; D008074:Lipoproteins; D020033:Protein Isoforms; C051928:lipoprotein-associated coagulation inhibitor; D006493:Heparin; D010738:Type C Phospholipases