Endothelial Cell Destruction by Polymorphonuclear Leukocytes Incubated with Sera from Patients with Systemic Lupus Erythematosus (SLE)

Abstract

When normal polymorphonuclear leukocytes (PMN) were incubated with sera from patients with active systemic lupus erythematows (SLE), a significantly increased cytotoxicity against human cultured vascular endothelial cells (EC), compared with normal control sera, was demonstrated by the standard ⁵¹Cr release method. The degree of this cytotoxicity was correlated with the immune complex level in each serum. The cytotoxicity did not correlate with the presence of anti-EC antibody. An absorption study with Clq-Sepharose 4B further suggested that the immune complexes are the factor which induce cytotoxicity. A gel fractionation study, however, indicated the heterogenity of the cytotoxic activity, and suggested the possible contribution of other substances including anti-EC, at least in some of the patients. This type of cytotoxicity may initiate the inflammatory process including vascular damage of the disease.

Key Words:

• systemic lupus erythematosus
• polyrnorphonuclear leukocytes
• endothelial cells
• immune complexes
• anti-endothelial cell antibody