CD21 low B cells in systemic sclerosis: A possible marker of vascular complications.

Objectives: To evaluate expansion of CD21 ^low B cells and their role in B cell homeostasis, apoptosis, clinical manifestations and serum vascular endothelial growth factor (VEGF) in systemic sclerosis (SSc).
Materials and Methods: 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.
Results: SSc patients with expanded CD21 ^low B cells (SSc-CD21 ^low ) show a distinct B cell profile with increased memory B cells compared to patients without CD21 ^low B cells (SSc-CD21 ⁺ ). Renal resistive index, systolic pulmonary arterial pressure and FVC/DLCO ratio were significantly higher in SSc-CD21 ^low group than SSc-CD21 ⁺ , DLCO was lower in SSc-CD21 ^low group than SSc-CD21 ⁺ . We found a positive linear correlation between CD21 ^low and sPAP, RI and FVC/DLCO ratio whereas a negative correlation was observed between CD21 ^low and DLCO and VEGF levels.
Conclusions: CD21 ^low B cells are increased in SSc patients with visceral vascular manifestations.
Competing Interests: Declaration of Competing Interest None.
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