[Effect of interleukin-6 promoter DNA methylation on the pathogenesis of systemic lupus erythematosus].

ABSTRACT

Objective: To analyze peripheral blood interleukin-6 (IL-6) promoter DNA methylation status and its clinical significance in patients with systemic lupus erythematosus (SLE). Methods: Blood samples of 41 adult patients with SLE and 20 healthy controls were collected.The methylation status of IL-6 promoter was determined by methylation specific polymerase chain reaction (MSP). The IL-6 expression was detected by real-time PCR.Correlations between IL-6 promoter methylation status and clinical features or laboratory findings in patients with SLE were analyzed. Results: The levels of IL-6 mRNA were significantly higher in peripheral blood of SLE.DNA methylation levels of IL-6 promoter were reduced in SLE patients as compared with healthy controls.The methylation status and expression of IL-6 in peripheral blood reflected the levels in peripheral blood mononuclear cells (PBMCs). Significantly positive correlation was found between IL-6 hypomethylation and renal disorder, as well as hypocomplementemia in patients with SLE. Conclusion: Hypomethylation of interleukin-6 promoter in peripheral blood might be involved in the etiology of SLE.