Expression and clinical significance of interleukin-17 and Th17 cells in the peripheral blood of patients with systemic lupus erythematosus / 中华风湿病学杂志

ABSTRACT

Objective To determine the protein and mRNA levels ofinterleukin-17 (IL-17) and the proportion of Th17 cells in the peripheral blood of patients with systemic lupus erythematosus (SLE) and their clinical significance is analyzed. Methods Twenty-five hospitalized SLE patients were recruited and twentytwo healthy volunteers were enrolled as normal controls. Plasma protein and mRNA of IL-17 in the peripheral blood were measured by enzyme-linked immunosorbent assay and real time-PCR respectively. Flow cytometric assay was used to analyze the percentage of Th17 cells in SLE patients. The relationship between IL-17/Th17 cells and clinical or laboratory parameters of SLE patients was explored. Students' t-test and Spearman's correlation was used to evaluate the relationship between mRNA level and inflammatory parameters. Results The plasma concentration and mRNA level of IL-17 was significantly elevated in SLE patients as compared to the normal controls (P＜0.05). The percentage of Th17 cells in patients with SLE was higher than that of normal controls and was significantly increased in more active SLE patients and SLE with nephritis than less active SLE and SLE without nephritis (P＜0.05). Both plasma levels of IL-17 and the proportion of Th17 cells were positively correlated with SLEDAI (r=0.681, P＜0.01; r=0.426, P=0.034). Conclusion Plasma IL-17 protein and mRNA expression level and the percentage of Th17 cells in SLE patients are all significantly elevated and the close relationship between IL-17/Th17 cells and disease activity suggests that IL-17/Th17 may play an important role in the pathogenesis of SLE.