Evaluation of renal vascular lesions using circulating endothelial cells in patients with lupus nephritis.

OBJECTIVE Currently the detection of renal vascular lesions (VLS) mainly depends on biopsy examination, and lacks surrogate biomarkers for clinical dynamic evaluation. The aim of this study is to find the correlation between numbers of circulating endothelial cells (CECs) and renal VLS in lupus nephritis (LN). METHODS Thirty LN patients with VLS and 30 LN patients without VLS were recruited. Thirty age- and sex-matched healthy volunteers served as controls. CECs were isolated from peripheral blood with anti-CD-146-coated immunomagnetic Dynabeads and were counted under microscopy. Parameters of renal involvement, including blood urea nitrogen, serum creatinine, 24 h urine protein excretion and quantitative urine sedimentation were also measured. RESULTS The number of CECs showed no difference between LN patients without VLS and controls. In patients with VLS, the number of CECs was significantly higher than those without VLS (P < 0.01). A strong positive correlation was found between CECs and serum creatinine (r = 0.503, P < 0.01) and mean blood pressure (r = 0.423, P < 0.05). In all LN patients with VLS, CEC number of the patients with thrombotic microangiopathy (TMA) significantly increased compared with those without TMA (P < 0.01). CONCLUSION Numeration of CECs may serve as a potential and useful marker for vasculopathy in LN. Dynamic observations of CEC number can be used not only to provide evidence for monitoring disease severity and disease activity, but also to determine therapy efficacy in LN patients.