Circulating group II phospholipase A2 activity and antilipocortin antibodies in systemic lupus erythematosus. Correlative study with disease activity

Objective. Lipocortin (LC) and phospholipase A 2 (PLA 2 ) are involved in phospholipid metabolism, and on the cellular level LC seems to be an antagonist of PLA 2 . Since anti-LC 1 autoantibodies were found in systemic lupus erythematosus (SLE), we undertook a study of the relationship between PLA 2 , anti-LC1, and disease activity in a large group of patients with SLE. Methods. Sera from 81 patients with SLE were tested for the activity of extracellular PLA 2 and the presence and level of antilipocortin 1 [anti-LC1 (IgM) and anti-LC1 (IgG)] antibodies. Both were compared to SLE activity. Results. Mean PLA 2 activity was 4.6-fold higher in patients with SLE than in healthy controls (707±219 vs 154±6 u/ml, p<0.01)