The Significance Of Plasma Levels Of IL-18 And MCP-1 In Patients With Systemic Lupus Erythematosus

Objective: Recent studies shown that cytokines play an important role in thedevelopment of SLE. The objective of this study is to detect plasma levels of IL-18and MCP-1 in patients with SLE and normal controls, and to analyze the relationshipbetween SLE disease activity, C3, C4, anti-ds-DNA antibodies, 24-hour urineproteinuria and plasma MCP-1 and IL-18 levels, and to explore the possible roles ofIL-18 and MCP-1 in the pathogenesis of SLE, especially with renal injury. Try to finda special and sensitive biologic factor to help the diagnosis of SLE and to predict theprognosis, to provide clues to reveal the pathogenesis of SLE.Methods: The plasma levels of IL-18 and MCP-1 were assayed in 30 patients withLN, 10 patients with SLE without renal injury and 20 age-matched healthy controlsby ELISA. The differences in various SLE groups and the correlation with C3,anti-ds-DNA antibodies, 24-hour proteinuria, serum creatinine and the SLE diseaseactivity of plasma IL-18 and MCP-1 levels were researched.Results: 1. Plasma levels of IL-18 were significantly increased in SLE patientsdepending on the disease activity. Plasma levels of IL-18 in patients with LN weresignificantly higher than those in no-renal involvement group. Moreover, plasmalevels of IL-18 were highly correlated with the levels of serum creatinine, SLEDAI,24-hour proteinuria and anti-ds-DNA antibodies.2. The plasma level of MCP-1 were significantly higher in patients with active groupsthan inactive SLE groups and normal controls, but there were no significantdifference between patients with LN and no-renal involvement SLE group.Furthermore, there were correlation between the plasma level of MCP-1 and 24-hourproteinuria, anti-ds-DNA antibodies, the levels of serum creatinine and the plasmaMCP-1 levels significantly correlated with SLEDAI score.3. There was correlation between plasma levels of IL-18 and MCP-1.Conclusions: 1. Plasma levels of IL-18 were significantly increased in SLE patientsdepending on the disease activity and correlated with the SLEDAI score. Plasmalevels of IL-18 may predict renal injury in SLE. The measurement of plasma IL-18 may be a useful indicator in SLE with renal involvement.2. Plasma MCP-1 levels were significantly correlated with SLE of disease activity,whereas not in SLE patients with renal involvement. And plasma MCP-1 levels not asgood as IL-18 reflected the renal involvement of SLE.3. These results suggest that plasma levels of IL-18 and MCP-1 combination with theclinical symptoms and the indicators of laboratory examination in patients with SLEmaybe the useful noninvase tool for monitoring the disease activity, IL-18 and MCP-1may be the drug targets ofbiotherapy in patients with SLE.4. IL-18 and MCP-1 may play a crucial role in the progress and development of SLEby the interaction of cytokine network.