Anti-endothelial cell antibodies are associated with apoptotic endothelial microparticles, endothelial sloughing and...

Area of Science:

• Immunology
• Vascular Biology
• Rheumatology

Background:

• Systemic sclerosis (SSc) involves endothelial damage, with anti-endothelial cell antibodies (AECAs) potentially driving vascular injury.
• Endothelial microparticles (EMPs) and circulating endothelial cells (CECs) are indicators of endothelial damage.

Purpose of the Study:

• To investigate the relationship between AECAs and markers of endothelial damage (EMPs and CECs) in SSc patients.
• To determine if AECAs impact endothelial repair capacity by assessing endothelial progenitor cells (EPCs).

Main Methods:

• Serum samples from 47 SSc patients were analyzed for AECAs using indirect immunofluorescence.
• EMPs, CECs, and EPCs were quantified using flow cytometry after isolation from peripheral blood and plasma.
• EPCs were further analyzed for expression of VEGFR2 and Tie2 receptors.

Main Results:

• AECAs were detected in 44.7% of SSc patients and significantly correlated with elevated total and apoptotic EMPs.
• Patients with AECAs exhibited higher levels of total and activated CECs.
• While total EPCs did not differ, AECAs were negatively associated with EPCs expressing VEGFR2 or Tie2, indicating impaired angiogenic potential.

Conclusions:

• AECAs are associated with increased endothelial damage in SSc, as indicated by higher EMP and CEC levels.
• AECAs contribute to endothelial cell apoptosis rather than activation.
• AECAs may impair vascular repair in SSc by reducing the number of functional angiogenic EPCs.