Circulating endothelial microparticles in acute ischemic stroke: a link to severity, lesion volume and outcome

J Thromb Haemost. 2006 Jun;4(6):1296-302. doi: 10.1111/j.1538-7836.2006.01911.x.


Background: Endothelial membrane microparticles (EMP) in plasma are elevated in several vascular diseases.

Objectives: To test the hypothesis that EMP would be increased in patients with acute ischemic stroke and would correlate with stroke severity, brain lesion volume and outcome.

Patients and methods: Forty-one patients were studied and divided into two groups based on the National Institutes of Health Stroke Scale (NIHSS) score: 20 patients with mild stroke (NIHSS score < 5) and 21 patients with moderate-severe stroke (NIHSS score > or = 5). Lesion volume was measured using diffusion-weighted magnetic resonance imaging and discharge outcome was based on the discharge Barthel and Rankin scores. Twenty-three age-matched control subjects were also studied. Using flow cytometry, endoglin-positive EMP: CD105+ CD41a-CD45- (E(+)EMP), specific endothelial EMP expressing VE-cadherin and endoglin: CD105+CD144+ (C(+)EMP), EMP expressing phosphatidylserine: CD105+PS+ CD41a- (PS(+)EMP) and EMP expressing ICAM-1: CD105+CD54+ CD45- (I(+)EMP) were analyzed.

Results: Significantly higher PS(+)EMP counts were observed in the group of acute ischemic stroke patients [median 59 (25th-75th percentile: 28-86) MP microL(-1)] relative to the controls [28 (14-36) MP microL(-1)] (P = 0.002). All four EMP phenotypes studied were elevated in the subgroup of moderate-severe stroke patients relative to the controls (all P < 0.05). In the patients with acute ischemic stroke three EMP phenotypes (E(+)EMP, PS(+)EMP and I(+)EMP) correlated significantly with brain lesion volume, with I(+)EMP (P = 0.002) showing the strongest correlation. Admission counts of C(+)EMP (P = 0.0003) and E(+)EMP (P = 0.003) correlated significantly with discharge clinical outcome.

Conclusions: Certain circulating EMP phenotypes may be associated with severity, lesion volume and outcome of acute ischemic stroke. EMP analysis shows promising contribution to understanding stroke pathophysiology.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Antigens, CD / analysis
  • Brain / pathology
  • Brain Ischemia / blood*
  • Brain Ischemia / therapy
  • Cadherins / analysis
  • Case-Control Studies
  • Endoglin
  • Endothelium, Vascular / cytology*
  • Female
  • Humans
  • Intercellular Adhesion Molecule-1 / analysis
  • Male
  • Middle Aged
  • Particle Size
  • Phosphatidylserines / analysis
  • Receptors, Cell Surface / analysis
  • Severity of Illness Index
  • Stroke / blood*
  • Stroke / pathology
  • Stroke / therapy


  • Antigens, CD
  • Cadherins
  • ENG protein, human
  • Endoglin
  • Phosphatidylserines
  • Receptors, Cell Surface
  • cadherin 5
  • Intercellular Adhesion Molecule-1