RESUMO
Osteopontin [OPN] is an extracellular matrix protein of pleotropic properties that has been recognized as a potential inflammatory cytokine. Also it has immunological activities including stimulation of T-helper type 1 lymphocyte response and B-cell antibody synthesis. IL-18 has multiple biological activities that are important in generating Th1 responses and inflammatory tissue damage. We measured the plasma concentration of OPN and the plasma IL-18 concentration in 24 SLE patients and 20 sex and age matched control subjects using an enzyme- linked immunosorbent assay. Plasma OPN concentrations and plasma IL-18 concentrations were significantly higher in SLE patients than in the control group [both p<0.001]. The increase in OPN and IL-18 concentrations correlated positively and significantly with SLE activity [r= 0.831, p<0.001] and [r = 0.826, p<0.001] respectively. Also, there was a highly significant positive correlation between OPN and IL-18 [r=0.75, p<0.001]