Elevated Plasma Levels of Soluble Platelet Glycoprotein VI (GPVI) in Patients with Thrombotic Patients

Abstract Abstract 5145 Introduction Thrombotic microangiopathy (TMA) is caused by various conditions, such as decreased a ADAMTS13 level, activated or injured vascular endothelial cells or activated platelets and it must be diagnosed at the early stage. This study, examined the activation of platelets by measuring of soluble platelet glycoprotein VI (sGPVI) level in patients with TMA. Materials and Methods The plasma levels of sGPVI, ADAMTS13 activity, von Willebrand factor (VWF) and VWF propeptide (VWFpp) were measured in 40 healthy volunteers, 46 patients without thrombosis (TH), 15 postoperative patients, 13 with disseminated intravascular coagulation (DIC) and 70 with TMA. The plasma levels of GPVI and VWFpp were measured by ELISA and ADAMTS13 was measured by the FRETS assay. There were 27 TMA with markedly decreased ADAMTS13 levels (TMA-ADAMTS13) and 43 TMA without (TMA-Other). Results The plasma levels of sGPVI (median; 25. 0–75. 0%tile) were significantly higher in patients without TH (16. 2 ng/mL 12. 6–22. 5 ng/mL), postoperative patients (31. 6 ng/mL; 28. 3–35. 1 ng/mL), DIC (44. 5 ng/mL; 36. 6– 60. 8 ng/mL), TMA (40. 8 ng/mL; 32. 9–56. 7 ng/mL) than in healthy volunteers (11. 4 ng/mL; 9. 1–14. 8 ng/mL). In addition, the plasma levels of sGPVI post in postoperative patients were significantly higher than in patients without TH (p< 0. 001), and these levels were also significantly higher in those with TMA and DIC than in without TH (p< 0. 001, respectively). The plasma levels of sGPVI were significantly higher in patients with TTP-ADAMTS13 (36. 8 ng/mL; 30. 5–49. 0 ng/mL) and TMA-Other (51. 9 ng/mL; 37. 4–66. 3 ng/mL) than in patients without TH (p< 0. 001, respectively). Conclusion The measurement of sGPVI is therefore considered to be important for the diagnosis of TMA. Disclosures: Wada: Mochida pharmaceutical CO., LTD: Suporting GPVI assay Other.