Interleukin-1 receptor antagonist in patients with active systemic lupus erythematosus: enhanced production by monocytes and correlation with disease activity

To evaluate the relationship between the serum concentration of interleukin-1 receptor antagonist (IL-1Ra) and systemic lupus erythematosus (SLE) disease activity, and to investigate the expression of IL-1Ra messenger RNA (mRNA) and its production by monocytes from patients with SLE.Serum IL-1Ra was measured by enzyme-linked immunosorbent assay, and expression of IL-1Ra mRNA was determined by Northern blotting.Serum IL-1Ra concentrations were...