Fibroblast Tissue Factor: Calcium and Ionophore Induce Shape Changes, Release of Membrane Vesicles, and Redistribution of Tissue Factor Antigen in Addition to Increased Procoagulant Activity
نویسندگان
چکیده
The coagulant activity of tissue factor (TF) in the membranes of cultured cells is increased after physical disruption f the cells, and a similar increase can be elicited by treatment of cell cultures with calcium ionophore and calcium. We observed that the supernatants of cultures treated with calcium and ionophore CBI-A23187 contained more TF activity than those of control cultures. Phase contrast microscopy showed that cultures treated with ionophore and calcium contained rounded cells, membrane vesicles, and cell fragments. Laser-activated fluorescence microscopy of cells stained for tissue factor antigen showed that 4-Br-A23187, in the presence of 5 mmol/L calcium, caused progressive changes in cell morphology. Treatment of cultures with
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Fibroblast Tissue Factor: Calcium and Ionophore Induce Shape Changes, Release of Membrane Vesicles, and Redistribution of Tissue Factor Antigen in Addition to Increased Procoagulant Activity
The coagulant activity of tissue factor (TF) in the membranes of cultured cells is increased after physical disruption f the cells, and a similar increase can be elicited by treatment of cell cultures with calcium ionophore and calcium. We observed that the supernatants of cultures treated with calcium and ionophore CBI-A23187 contained more TF activity than those of control cultures. Phase con...
متن کاملFibroblast tissue factor: calcium and ionophore induce shape changes, release of membrane vesicles, and redistribution of tissue factor antigen in addition to increased procoagulant activity.
The coagulant activity of tissue factor (TF) in the membranes of cultured cells is increased after physical disruption of the cells, and a similar increase can be elicited by treatment of cell cultures with calcium ionophore and calcium. We observed that the supernatants of cultures treated with calcium and ionophore 4-Br-A23187 contained more TF activity than those of control cultures. Phase c...
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Intact bovine fibroblasts, pericytes, and kidney cells manifested significantly less tissue factor procoagulant activity than their disrupted counterparts. Addition of calcium ionophore A23187 rapidly and reversibly enhanced the cell-surface expression of tissue factor in intact cells up to the level achieved by disruption. Inhibitors of calmodulin blocked the ionophore-dependent enhancement of...
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