IMPAIRED PRODUCTION OF IL-12 IN SYSTEM LUPUS-ERYTHEMATOSUS - II - IL-12 PRODUCTION IN-VITRO IS CORRELATED NEGATIVELY WITH SERUM IL-10, POSITIVELY WITH SERUM IFN-GAMMA AND NEGATIVELY WITH DISEASE-ACTIVITY IN SLE

Interleukin 12 (IL-12) is a key cytokine in regulating type 1 or type 2 cytokine production and in determining the nature of immune response s. Our previous studies demonstrated that its production was significa ntly impaired in systemic lupus erythematosus (SLE) patients and this deficient IL-12 production was mainly mediated by excessive endogenous IL-10. The present study was designed to further reveal the relations hips of in vitro IL-12 production with abnormalities of in vivo cytoki ne synthesis and disease activity in SLE. Experimental results showed that IL-12 production in vitro was inversely correlated with serum IL- 10 level, anti-ds DNA antibody level and SLE disease activity index (D AI), but positively correlated with serum interferon gamma (IFN-gamma) level, with which serum IL-10 correlated negatively, Data also showed that serum IL-10 was significantly higher than that of controls and c losely correlated with anti-ds DNA antibody level and SLEDAI. The stud y confirms that deficient IL-12 production in SLE patients is associat ed with in vivo abnormalities of cytokine production, especially with increased IL-10 production. (C) 1998 Academic Press Limited.