Circulating endothelial progenitor cells in systemic sclerosis: association with disease severity

Area of Science:

• Immunology
• Vascular Biology
• Rheumatology

Background:

• Circulating endothelial progenitor cells (EPCs) play a role in vascular repair.
• Data on EPC detection and numbers in systemic sclerosis (SSc) are inconsistent.
• Understanding EPC dynamics in SSc is crucial for disease management.

Purpose of the Study:

• To quantify circulating EPCs in SSc patients and healthy controls using validated markers.
• To assess the late outgrowth capacity of EPCs in SSc.
• To correlate EPC numbers with disease severity and clinical manifestations.

Main Methods:

• EPCs (Lin-/7AAD-/CD34+/CD133+/VEGFR-2+) were quantified via cell sorting and flow cytometry.
• Late outgrowth colony-forming units (CFU) were assessed in cell culture.
• 50 SSc patients and 26 healthy controls were included.

Main Results:

• SSc patients had significantly higher circulating EPC counts than controls.
• Lower EPC counts correlated with higher Medsger's severity scores and digital ulcers.
• No significant difference in late outgrowth EPC-CFU numbers was observed between groups.

Conclusions:

• Circulating EPC levels are elevated in SSc, indicating bone marrow mobilization.
• Reduced EPC counts in severe SSc with digital lesions suggest increased homing to affected sites.
• Validated EPC markers provide a reliable measure for further biomarker evaluation.