Anti-endothelial cell autoantibodies and soluble markers of endothelial cell dysfunction in systemic lupus erythematosus.

Objective: To determine if anti-endothelial cell antibodies (AECA) and plasma markers of endothelial cell function are related to disease severity in systemic lupus erythematosus (SLE).

Methods: We measured AECA by human umbilical vein endothelial cell binding, endothelial markers von Willebrand factor, soluble thrombomodulin, and soluble E-selectin by ELISA, and disease severity by SLEDAI and SLICC/ACR in 35 patients with SLE.

Results: Despite high levels of IgG AECA (p = 0.001) and von Willebrand factor (p = 0.0007) compared to 21 healthy controls, we found a positive correlation only between IgG AECA and the SLEDAI index (r = 0.393, p = 0.021).

Conclusion: IgG AECA seem to be related to disease activity in SLE, possibly in a pathogenic role. Conversely, plasma markers of endothelial cell damage seem to be an epiphenomenon and may simply be related to excess inflammation.