Expression of interleukin-32 in peripheral blood of rheumatoid arthritis patients and its clinical significance / 中华风湿病学杂志

ABSTRACT

Objective To detect the expression levels of interleukin (IL)-32 and tumor necrosis factor (TNF)-α in peripheral blood of rheumatoid arthritis (RA) patients,and analyze the relations between IL-32 and level of erythrocytes (ESR),creactive protein (CRP),rheumatoid factor (RF),the disease activity index 28 (DAS28) scores in RA patients.The aim of this study is to identify the clinical significance of IL-32 in RA patient.Methods We collected 97 specimens of peripheral blood from RA patients,including 36 RA patients with high active disease,33 RA patients with moderate active disease,28 RA patients with stable disease,36 non-RA connective tissue diseases (CTD) patients and 30 healthy volunteers.The mRNA levels of IL-32,TNF-α in the peripheral blood mononuclear cells (PBMC) were determined by quantitative real-time PCR (QRT-PCR).The concentration of IL-32,TNF-αt in plasma were detected by enzyme linked immunosorbent assay (ELISA),one-way AN OVA and Spearman's corrclation and multiple linear regression were adopted for statistical analysis.Results ①The mRNA levels of IL-32 and TNF-α in active RA patients were higher than those in healthy control group (0.29±0.07,0.24±0.06 vs 0.11±0.06 for IL-32 in the high active RA group and moderate active RA group versus the healthy group; and 0.042±0.022,0.012±0.006 vs 0.004±0.002 for TNF-α in the high active RA group and moderate active RA group versus the healthy group,P＜0.01),and than those in stable RA patients,and non-RA CTD patients.There was no significant difference among the stable disease groups,healthy control group and non-RA CTD group in the level of mRNA.② The concentration of IL-32,TNF-α in the plasma of RA patients with active disease was higher than that of healthy control group [(107±42) pg/ml,(66±27) pg/ml vs (20±10) pg/ml for IL-32 in the high active RA group and moderate active RA group versus the healthy group; and (261±77) pg/ml,(186±84) pg/ml vs (72±20) pg/ml for TNF-αt in the high active RA group and moderate active RA group versus the healthy group,P＜0.01].③ The expression levels of IL-32 was positively correlated with the level of TNF-α,ESR,CRP,RF,DAS28 scores in the plasma of RA patients (r=0.568,0.321,0.185,0.325,0.303 respectively,P＜0.01).④ The expression levels of IL-32 was positively correlated with the level of TNF-α (the regression coefficients and P values were b=1.721,P＜0.01 and b=0.176,P＜0.01 respectively).Conclusion The levels of IL-32 in peripheral blood may be used as an indicator for disease activity of RA.