SUPPRESSION OF IMMUNOGLOBULIN-SYNTHESIS BY MONOCYTES IN HEALTH AND IN PATIENTS WITH SYSTEMIC LUPUS-ERYTHEMATOSUS

Immunoglobulin (Ig) synthesis by cultured mononuclear leukocytes from healthy subjects was stimulated with pokeweed mitogen and measured by immunofluorescence after 14 days in culture. Optimal Ig synthesis was recorded at 1 × 106 lymphocytes/ml. At 3 × 106 lymphocytes/ml, Ig synthesis was much lower; an inverse relationship was observed between Ig synthesis and monocyte percentages among these cultured cells (P < 0.001). At 3 × 106 lymphocytes/ml, more active Ig synthesis was restored by removing cells that adhere to foreign surfaces or ingest iron particles or by damaging monocytes by preincubation with carrageenan. Spontaneous Ig synthesis by cells from patients with systemic lupus erythematosus was elevated. With this disease, a regulatory influence by monocytes could not be demonstrated. © 1979.