CD21low B cells in systemic sclerosis: A possible marker of vascular complications.

To evaluate expansion of CD21low B cells and their role in B cell homeostasis, apoptosis, clinical manifestations and serum vascular endothelial growth factor (VEGF) in systemic sclerosis (SSc). B-cells subpopulations and apoptosis have been assessed in 74 SSc patients and 20 healthy donors. Renal Doppler ultrasound, echocardiography, pulmonary function test and VEGF were performed. SSc patients with expanded CD21low B cells (SSc-CD21low) show a distinct B cell profile with increased memory B cells compared to patients without CD21low B cells (SSc-CD21+). Renal resistive index, systolic pulmonary arterial pressure and FVC/DLCO ratio were significantly higher in SSc-CD21low group than SSc-CD21+, DLCO was lower in SSc-CD21low group than SSc-CD21+. We found a positive linear correlation between CD21low and sPAP, RI and FVC/DLCO ratio whereas a negative correlation was observed between CD21low and DLCO and VEGF levels. CD21low B cells are increased in SSc patients with visceral vascular manifestations. • CD21low percentage of B cells are higher in SSc patients than healthy donor. • CD21low percentage is higher in SSc patients with visceral vascular damage. • VEGF increases in SSc patients with low CD21low percentage. • CD21low percentage is a marker of impaired angiogenesis and vascular damage. [ABSTRACT FROM AUTHOR]