ESTIMATION OF PROTEIN-C AND PROTEIN-S IN PATIENTS WITH NONSPECIFIC AORTIC ARTERITIS

Solid-phase enzyme immunoassay estimated S and C protein levels in 10 patients with nonspecific aortic arteritis (NAA). Lowered concentratio ns of total protein S (< 70%) occurred in 8 (80%) of 10 NAA patients, in 3 of them protein C was also low. Isolated reduction of protein C w as encountered only in one patient. Four patients (44%) of 9 had antib odies to phospholipids, as a rule, in low concentrations. 3 of them ha d low total protein S concentrations against normal C protein. 4 patie nts (40%) showed elevated concentrations of WF antigen concentrations. No relationship was noted between a fall in total protein S, C concen trations and clinical presentation of NAA, the disease activity, prese nce of antibodies to neutrophil cytoplasm and antibodies to endothelia l cells. Thus, a reduction in the levels of total protein S in NAA pat ients is induced by endothelial dysfunction unrelated to production of antibodies to phospholipids, neutrophil cytoplasm and vascular endoth elium.