Release from Intracellular Stores Is Responsible for Calcium Signaling with von Willebrand Factor in Human Platelets

Summary

Interaction of von Willebrand factor (VWF) with the platelet promotes hemostasis upon vascular injury. Such interaction raises intracellular free calcium concentration ([Ca2+]i) and induces platelet activation. The platelet [Ca2+]i increase is generally attributed to influx across the plasma membrane. The present study defined the contribution of intracellular calcium stores. Platelet [Ca2+]i was monitored with Fura-PE3. Ristocetin-mediated binding of VWF transiently elevated [Ca2+]i after a lag phase. Studies with 63 healthy donors consistently revealed a VWF-induced platelet [Ca2+]i signal in the absence of extracellular calcium; there was only modest enhancement with extracellular calcium. Blockade of plasma membrane calcium channels did not diminish the signal, whereas depletion or blockade of the intracellular calcium stores abolished it. These findings imply that release from intracellular stores is responsible for the VWF-induced platelet [Ca2+]i increase. Influx across the plasma membrane plays no more than a minor role, probably representing “capacitative entry” to refill the intracellular stores.

Keywords

Glycoprotein Ib-IX-V - intracellular calcium - platelet - signal transduction - von Willebrand factor

• References

• 1 Ruggeri ZM. Role of von Willebrand factor in platelet thrombus formation. Ann Med 2000; 32 (Suppl. 01) 2-9.
• 2 Savage B, Shattil SJ, Ruggeri ZM. Modulation of platelet function through adhesion receptors: a dual role for glycoprotein IIb-IIIa (integrin a. _IIb f3 ₃) mediated by fibrinogen and glycoprotein Ib von Willebrand factor. J Biol Chem 1992; 267: 11300-6.
• 3 Howard MA, Firkin BG. Ristocetin: a new tool in the investigation of platelet aggregation. Thromb Diath Haemorrh 1971; 26: 362-9.
• 4 Dardik R, Ruggeri ZM, Savion N, Gitel S, Martinowitz U, Chu V, Varon D. Platelet aggregation on extracellular matrix: effect of a recombinant GPIb-binding fragment of von Willebrand factor. Thromb Haemost 1993; 70: 522-6.
• 5 Konstantopoulos K, Chow TW, Turner NA, Hellums JD, Moake JL. Shear stress-induced binding of von Willebrand factor to platelets. Biorheology 1997; 34: 57-71.
• 6 Ozaki Y, Qi R, Satoh K, Asazuma N, Yatomi Y. Platelet activation mediated through membrane glycoproteins: involvement of tyrosine kinases. Semin Thromb Hemost 2000; 26: 47-51.
• 7 Dopheide SM, Yap CL, Jackson SP. Dynamic aspects of platelet adhesion under flow. Clin Exp Pharmacol Physiol 2001; 28: 355-63.
• 8 Kroll MH, Harris TS, Moake JL, Handin RI, Schafer AI. von Willebrand factor binding to platelet GpIb initiates signals for platelet activation. J Clin Invest 1991; 88: 1568-73.
• 9 Ikeda Y, Handa M, Kamata T, Kawano K, Kawai Y, Watanabe K, Kawakami K, Sakai K, Fukuyama M, Itagaki I, Yoshioka A, Ruggeri ZM. Transmembrane calcium influx associated with von Willebrand factor binding to GP Ib in the initiation of shear-induced platelet aggregation. Thromb Haemost 1993; 69: 496-502.
• 10 Ozaki Y, Satoh K, Yatomi Y, Miura S, Fujimura Y, Kume S. Protein tyrosine phosphorylation in human platelets induced by interaction between glycoprotein Ib and von Willebrand factor. Biochim Biophys Acta 1995; 1243: 482-8.
• 11 Mazzucato M, De Marco L, Pradella P, Masotti A, Pareti FI. Porcine von Willebrand factor binding to human platelet GPIb induces transmembrane calcium influx. Thromb Haemost 1996; 75: 655-60.
• 12 Yap CL, Hughan SC, Cranmer SL, Nesbitt WS, Rooney MM, Giuliano S, Kulkarni S, Dopheide SM, Yuan Y, Salem HH, Jackson SP. Synergistic adhesive interactions and signaling mechanisms operating between platelet glycoprotein Ib/IX and integrin α_IIbβ₃: studies in human platelets and transfected Chinese hamster ovary cells. J Biol Chem 2000; 275: 41377-88.
• 13 Scrutton MC. The platelet as a Ca2+-driven cell: mechanisms which may modulate Ca²⁺-driven responses. Adv Exp Med Biol 1993; 344: 1-15.
• 14 Francesconi MA, Deana R, Girolami A, Pontara E, Casonato A. Platelet aggregation induced by plasma from type IIB von Willebrand’s disease patients is associated with an increase in cytosolic Ca²⁺- concentration. Thromb Haemost 1993; 70: 697-701.
• 15 Chow TW, Hellums JD, Moake JL, Kroll MH. Shear stress-induced von Willebrand factor binding to platelet glycoprotein Ib initiates calcium influx associated with aggregation. Blood 1992; 80: 113-20.
• 16 Kermode JC, Zheng Q, Cook EP. Fluorescent indicators give biased estimates of intracellular free calcium change in aggregating platelets: implication for studies with human von Willebrand factor. Blood Cells Mol Dis 1996; 22: 238-53.
• 17 Milner EP, Zheng Q, Kermode JC. Ristocetin-mediated interaction of human von Willebrand factor with platelet glycoprotein Ib evokes a transient calcium signal: observations with Fura-PE3. J Lab Clin Med 1998; 131: 49-62.
• 18 Kermode JC, Zheng Q, Milner EP. Marked temperature dependence of the platelet calcium signal induced by human von Willebrand factor. Blood 1999; 94: 199-207.
• 19 Grynkiewicz G, Poenie M, Tsien RY. A new generation of Ca2+ indicators with greatly improved fluorescence properties. J Biol Chem 1985; 260: 3440-50.
• 20 Vorndran C, Minta A, Poenie M. New fluorescent calcium indicators designed for cytosolic retention or measuring calcium near membranes. Biophys J 1995; 69: 2112-24.
• 21 Tsien RY. New calcium indicators and buffers with high selectivity against magnesium and protons: design, synthesis, and properties of prototype structures. Biochemistry 1980; 19: 2396-404.
• 22 Rink TJ, Sage SO. Calcium signaling in human platelets. Annu Rev Physiol 1990; 52: 431-49.
• 23 Thastrup O, Cullen PJ, Drøbak BK, Hanley MR, Dawson AP. Thapsigargin, a tumor promoter, discharges intracellular Ca2+ stores by specific inhibition of the endoplasmic reticulum Ca2+-ATPase. Proc Natl Acad Sci USA 1990; 87: 2466-70.
• 24 Putney JW. Type 3 inositol 1,4,5-trisphosphate receptor and capacitative calcium entry. Cell Calcium 1997; 21: 257-61.
• 25 Gafni J, Munsch JA, Lam TH, Catlin MC, Costa LG, Molinski TF, Pessah IN. Xestospongins: potent membrane permeable blockers of the inositol 1,4,5-trisphosphate receptor. Neuron 1997; 19: 723-33.
• 26 Maruyama T, Kanaji T, Nakade S, Kanno T, Mikoshiba K. 2APB, 2-aminoethoxydiphenyl borate, a membrane-penetrable modulator of Ins(1,4,5)P₃ ^-induced Ca²⁺-release. J Biochem 1997; 122: 498-505.
• 27 Barritt GJ. Receptor-activated Ca²⁺-inflow in animal cells: a variety of pathways tailored to meet different intracellular Ca2+ signalling requirements. Biochem J 1999; 337: 153-69.