Anti-endothelial cell antibodies in patients with systemic lupus erythematosus.

Using unfixed cultured endothelial cells isolated from human umbilical veins, we performed cellular enzyme-linked immunosorbent assay (ELISA) for the detection of anti-endothelial cell antibodies (AECA) in the sera of 74 patients with systemic lupus erythematosus (SLE) and 82 normal individuals. Significantly higher levels of AECA were demonstrated in the patient group, as compared with the control group (0.12 +/- 0.07 vs 0.07 +/- 0.05, p less than 0.001). Fourteen of the 74 patients (19%) had endothelial cell binding activities 2 standard deviations above the mean for healthy controls. Patients with cutaneous vasculitis, Raynaud's phenomenon, or lupus nephropathy had higher mean values of AECA than those patients without such manifestations, although the differences were not statistically significant. Patients with central nervous system involvement did not have increased levels of AECA. There was a close relationship between raised levels of AECA and hypocomplementemia (p less than 0.05). No difference was observed between patients positive and negative for anti-native DNA antibodies. We conclude that frequent occurrence of AECA is confirmed in Chinese patients with SLE and that the appearance of AECA is probably related to lupus activity. However, the role of AECA in vascular damage in SLE needs further clarification.