Circulating Angiogenic T Cells Are Increased in Lupus Nephritis Patients

Abstract

BACKGROUND Patients with systemic lupus erythematosus (SLE), especially with lupus nephritis (LN), undergo vascular damage and repair during the course of the disease. Since the recently identified angiogenic T cells (Tang) are involved in endothelial repair coupled with endothelial progenitor cells (EPCs), this study investigated the circulating Tang cells in LN patients and their potential correlations with disease features. MATERIAL AND METHODS Circulating Tang cells and EPCs were assessed by flow cytometry in peripheral blood samples from 67 SLE patients; of these, 32 had LN and 30 were matched healthy controls (HCs). The plasma levels of interleukin IL-17, IL-8, and vascular endothelial growth factor (VEGF) were quantified by immunoassays. RESULTS The percentage of circulating Tang cells in LN patients was significantly increased as compared to the non-LN patients and HCs, and they were positively correlated with the level of EPC and VEGF. Additionally, circulating Tang cell percentages were positively correlated with the extent of proteinuria in LN patients. CONCLUSIONS The increased levels of circulating Tang cells in LN patients might play a role in the balance of endothelium dysfunction in these patients.

Figure 1

Presence of circulating Tang cells in SLE patients and HCs. (A) Flow cytometric dot-plots of circulating Tang cells (CD31+CXCR4+ cells in CD3+ T cells) obtained from 1 representative healthy control (HC), and SLE patients with lupus nephritis (LN) and without lupus nephritis (non-LN). Percentages of circulating Tang cells (B) and EPCs (CD34+CD133+VEGFR2+ cells) (C) in HC, LN, and non-LN patients.

Figure 2

Plasma levels of cytokines in SLE patients and HCs. The plasma levels of IL-17 (A), IL-8 (B), and VEGF (C) in SLE patients with lupus nephritis (LN), SLE patients without lupus nephritis (non-LN), and HCs.