Measurement of platelet p-selectin expression by flow cytometry in patients with acute ischemic stroke

Aims: The aim of this study was to asses the platelet activation in the acute phase of ischemic stroke and transient ischemic attack (TIA) by defining p-selectin (CD62) expression by flow cytometry in vivo – without stimulation with agonists. We also studied whether antiplatelet therapy supresses the levels of baseline p-selectin expression and verified if there is a correlation between platelet CD62 expression and the type of ischemic stroke.

Methods: We determined the expression of platelet surface p-selectin using whole-blood flow cytometry within the first 48-hours after onset of cerebral symptoms in patients with atherothrombotic and lacunar ischemic stroke and in healthy volunteers. We studied the realationship between antiplatelet medication and the type of ischemic stroke to baseline p-selectin expression.

Results: Patients with acute cerebral ischemia have an excess of circulating platelets that express p-selectin, compared to healthy volunteers. The difference between average p-selectin expression in the group of healthy volunteers and the group of patients with stroke was statistically significant (p-value < 0,000001). Patients with stroke without antiplatelet medication showed a higher p-selectin expression than patients with antiplatelet medication (ASA, CLP, or ASA and CLP), hovewer, the difference was not statistically significant. There is no relationship between CD62 expression and the type of stroke.

Conclusions: We can conclude that p-selectin is a highly sensitive blood biomarker of increased platelet activation. Antiplatelet therapy suppresses baseline p-selectin expression only minimally, insignificantly according to our results.