Natural killer cell activity of peripheral blood mononuclear cells from patients with various forms of lupus erythematosus

: Natural killer (NK) cell activity of peripheral blood mononuclear cells from 28 patients with cutaneous discoid lupus erythematosus, seven with subacute cutaneous lupus erythematosus, and 17 with systemic lupus erythematosus was studied using a 4 h 51Cr release assay using K-562 cells as target cells. NK cell activity was found to be markedly decreased not only in patients with systemic lupus erythematosus but also in a proportion of cases of subacute cutaneous lupus erythematosus and cutaneous discoid lupus erythematosus (57% and 39% respectively). There was a relationship between the activity and severity of LE and the decrease in NK cell activity.