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Platelet C4d is associated with acute ischemic stroke and stroke severity
Nidhi Mehta1, Ken Uchino, Saeed Fakhran
1University of Pittsburgh School of the Health Sciences, University of Pittsburgh, PA, USA.
Stroke
|October 18, 2008
Summary
Platelets with complement C4d are linked to severe ischemic stroke. This finding suggests platelet C4d may indicate cerebrovascular inflammation and thrombosis in stroke patients.
Area of Science:
- Immunology
- Neurology
- Vascular Medicine
Background:
- Platelets expressing complement C4d (C4d) are highly specific for systemic lupus erythematosus (SLE).
- C4d-positive platelets are associated with neuropsychiatric lupus.
- The role of platelet C4d in acute ischemic stroke is not well understood.
Purpose of the Study:
- To compare the prevalence of platelet C4d in patients with acute ischemic stroke versus controls.
- To investigate the clinical associations of platelet C4d in acute ischemic stroke.
Main Methods:
- Eighty patients hospitalized for acute ischemic stroke were recruited.
- Stroke severity was assessed using the National Institutes of Health Stroke Scale (NIH-SS).
- Platelet C4d levels were measured by flow cytometry, and infarct volume was determined by MRI.
Main Results:
- Ten percent of acute ischemic stroke patients were positive for platelet C4d, significantly higher than healthy controls (0%) and non-SLE inflammatory disease patients (2%).
- Platelet C4d-positive patients had more severe strokes (median NIH-SS: 17.5 vs. 5) and larger infarct volumes.
- Platelet C4d positivity independently correlated with stroke severity and infarct volume.
Conclusions:
- Platelet C4d is significantly associated with severe acute ischemic stroke.
- Platelet C4d may serve as a biomarker and pathogenic indicator linking cerebrovascular inflammation and thrombosis.
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