The effects of scleroderma serum on human microvascular endothelial cells

To investigate the vascular immunopathology of systemic sclerosis, we developed a model consisting of human microvascular endothelial cells, leukocytes, and serum. Sera from 19% of the patients studied mediated antibody-dependent cellular cytotoxicity against endothelial cells. Some sera also mediated cytotoxicity against aortic endothelium and fibroblasts. K lymphocytes, the cells that mediate antibody-dependent cellular cytotoxicity, were identified in the skin of some patients. The sera alone were not cytotoxic or growth inhibitory, and did not affect endothelial prostacyclin production.