Microparticles from Endothelial Cells and Immune Cells in Patients with Takayasu Arteritis.

Aim: This study was designed to analyze microparticles (MPs) from endothelial cells (EMPs) and immune cells from healthy individuals and paitents with Takayasu arteritis (TA), and any possible relationships between MPs and TA acitivity.

Methods: MPs derived from the plasma of 51 subjects were analyzed, including 32 patients with TA and 19 healthy individuals. Flow cytometry was performed with Annexin (Anx)-V and antibodies against surface markers of endothelial cells (CD144), T cells (CD3), B cells (CD19), and monocytes (CD14).

Results: The concentrations of total EMPs, AnxV＋ EMPs and AnxV- EMPs were significantly increased when comparing patients with TA and healthy controls (54×10 vs. 32×10 MPs /ml, P=0.0004; 22×10 vs. 12×10 MPs /ml, P=0.0006; and 31×10 vs. 19×10 MPs /ml, P=0.0005), and comparing active TA patients with remission ones (85×10 vs. 45×10 MPs /ml, P=0.016; 39×10 vs. 14×10 MPs /ml, P=0.0092; and 47×10 vs.29×10 MPs /ml, P=0.0371). In addition, the concentrations of total EMPs (odds ratio [OR]=1.024, 95% confidence interval [CI]: 1.001 to 1.048, P=0.037), AnxV＋(OR=1.089, 95%CI: 1.011 to 1.172, P=0.024), and AnxV- EMPs (OR=1.029, 95% CI: 1.002 to 1.056, P=0.034) were positively related to TA activity. With multiple linear regression analysis, platelet was associated with both total and AnxV- EMP concentrations independently, while erythrocyte sedimentation rate was independently correlated with AnxV＋EMPs.

Conclusion: Concentrations of endothelial microparticles are correlated with inflammation in Takayasu arteritis and may be useful markers to assess disease activity.