Profiles of cytokines (TNF alpha and IL-6) and acute phase proteins (CRP and alpha 1AG) related to the disease course in patients with systemic lupus erythematosus.

Tumor necrosis factor alpha (TNF alpha) and interleukin-6 (IL-6) play a main role in inducing acute phase protein production by hepatocytes. This study describes the serum levels of TNF alpha and IL-6 in relation to serum levels of C-reactive protein (CRP) and alpha 1-acid glycoprotein (alpha 1AG) in three systemic lupus erythematosus (SLE) patients. Disease courses of these patients were divided in a total of 19 clinical periods, according to the clinical symptoms and interleukin profiles. Significantly elevated TNF alpha levels were found in all but three of the defined periods, without being associated with disease activity. In only four of the defined periods elevated TNF alpha were observed combined with elevated IL-6 and CRP levels. Two of these periods coincided with minor symptoms of SLE, one with an exacerbation and the other one with a systemic infection while SLE activity was low. All other periods showed varying combinations of elevated TNF alpha and/or IL-6 levels being followed or not by elevated CRP levels. Significantly raised alpha 1AG levels were measured in all clinical periods. In most of the observed periods a dissociation was found between TNF alpha and IL-6 and also between the different cytokine (TNF alpha and IL-6) levels and acute phase protein (CRP and alpha 1AG) levels. These data could not be explained by differences in disease course or influences of medication. We conclude that more factors other than TNF alpha and IL-6 must play a role in the regulatory pathway of the acute phase response in SLE.(ABSTRACT TRUNCATED AT 250 WORDS)