The expression of helper T cells 17/regulatory T cells balance associated factors in rheumatoid arthritis patients and their correlation with serum midkine / 中华风湿病学杂志

ABSTRACT

Objective To investigate the expression of helper T cells (Th)17/regulatory T cells (Treg) balance associated factors in rheumatoid arthritis (RA) patients and their correlation with serum midkine (MK).Methods A total of 60 RA patients were divided into active RA patients (n=32) and inactive RA patients group (n=28).MK level in sera was detected by enzyme linked immunosorbent assay (ELISA) in 60 patients with RA and 30 healthy controls (HCs).The fraction of CD4+CD25+FOXP3+ Treg cells and IL-17+CD4+ Th17 cells in RA patients and healthy controls were determined by flow cytometry (FCM), and the expreasion of Foxp3, RORγt, Signal transducer and activator of transcription (STAT) 3 and STAT5 mRNA were detected with real-time polymerase chain reaction (PCR).Results were evaluated using ANOVA followed by q tests for comparisons of Th17 population between active RA patients, inactive RA patients and HCs, t test was used for comparing of Foxp3, RORγt, STAT3, STAT5 mRNA between RA group and HCs.The correlations between serum MK concentration and peripheral Treg cells, Th17 cells, Foxp3, RORγt, STAT3, STAT5 mRNA were analyzed by Pearson's correlation analysis.Results The percentages of Treg cells from active RA patients, inactive RA patients and HCs were significantly different (F=129.6, P＜0.01), the percentages of Treg cells of active RA patients [(1.41±1.05)％] were lower than that of the inactive RA patients [(3.6±1.6)％;q =7.92, P＜0.05] and healthy group [(7.7±1.7)％;q=22.45, P＜0.05], and there was significant difference between healthy group and inactive RA group (q=14.53, P＜0.05).The percentages of Th17 cells of the three groups were also significantly different (F=36.3, P＜0.01),the percentage of Th17 cells of active RA patients [(1.84±1.01)％] was significantly higher than that of inactive RA patients [(0.71±0.28)％;q=9.59, P＜0.05] and healthy group (0.53±0.16)％ [(P＜0.05;q=1 1.10, P＜0.05], there was no significant difference between the inactive RA group and healthy group (q=1.51, P＞0.05).The expression of RORγt and STAT3 mRNA in RA patients was higher than that of healthy controls (t=5.84, P＜0.01;t=4.52, P＜0.01).The expression of Foxp3 and STAT5 mRNA in RA patients were lower than healthy controls (t=6.01, P＜0.01;t=2.18, P＜0.05).Serum MK values were correlated with STAT5 (r=-0.55, P＜0.01), but not with Foxp3, RORγt, STAT3 mRNA or the percentage of Treg/Th17 cells.Conclusion Serum MK expression and the percentage of Th17 cells increase, while the percentage of Treg cells decrease in RA patients.Serum MK values are negatively correlated with STAT5 mRNA which is associated with Th17/Treg balance.This may be important in the pathogenesis of RA.