Establishment of Flow Cytometric Immunobead Array for Detecting Plasma Von Willebrand Factor Activity and Its Clinical Application in the Prognosis of Ischemic Stroke / 中国实验血液学杂志

ABSTRACT

OBJECTIVE@#To establish a novel flow cytometric immunobead array (FCIA) for detecting plasma von Willebrand factor activity (vWFGPIbR) and apply it in ischemic stroke (IS).@*METHODS@#Microspheres coated with anti-human platelet glycoprotein Ibα (GPIbα) monoclonal antibody SZ151 IgG, were incubated with recombinant fragment of GPIbα, then added ristocetin and plasma, finally incubated with FITC-conjugated sheep-anti-human vWF IgG polyclonal antibody, and detected by flow cytometry. vWF antigen (vWFAg), vWFGPIbR, and vWF collagen binding assay (vWFCB) were also included for evaluating vWF levels in IS patients.@*RESULTS@#The intra-assay coefficient variations (CVs) and inter-assay CVs of FCIA were 7.7% and 13.5%, respectively. The slope of the linear regression was 0.9739 (r=0.855, P<0.001), and the Bland-Altman bias was 9.95%, indicating a good correlation between FCIA and ELISA. The FCIA had better sensitivity, specificity and accuracy as compared with those by ELISA (P<0.05). The levels of vWFAg, vWFGPIbR and vWFCB in IS patients were significantly higher in comparison with those in healthy controls (H=7.8, 6.4, 6.2, respectively, P<0.01), the level of vWFGPIbR in IS patients positively correlated with levels of vWFAg, high-sensitivity C-reactive protein, Autar score and hospitalization time.@*CONCLUSION@#The FCIA for detecting plasma vWFGPIbR is more specific and accurate than ELISA. The vWFGPIbR is involved in the paroxysm of IS, which could be used to evaluate the risk of thrombosis in IS patients.