ABSTRACT
Objective To analyze the expression of purinergic receptor P2X ligand-gated ion channel 7 (P2X7R) on different cells and peripheral blood mononuclear cell (PBMC) and to investigate its correlation with inflammatory cytokines in patients with SLE.Methods Flow cytometry was used to detect surface expression of P2X7R on lymphocytes,CD4+ cells,and CD19+ cell in 29 SLE patients and 28 healthy human controls to compare the difference between the SLE patients and the controls in P2X7R expression.Enzyme linked immunosorbent assay (ELISA) was performed to detect P2X7R-related serum cytokines interleukin (IL)-1β,IL-6,tumor necrosis factor (TNF)-α level.T test,Wilcoxon rank sum test,Spearman's correlation analysis were used for statitical analysis.Results ① SLE patients had significantly higher expression of P2X7R on CD4+,CD8+ lymphocytes compared to controls [CD4+ cells∶ 2.21(3.55) vs 0.89(1.15),Z=-1.527,P=0.015； CD19+ cells∶ 11.53(20.01) vs 6.66 (6.27),Z=-2.091,P=0.037]； ② The levels of three cytokines in patients with SLE were significantly higher than those in control.The positive relationship between P2X7R expression in lymphocytes with the serum IL-6 level was found in SLE patients (r=0.449,P=0.015)；③ Patients with arthritis showed significantly higher expression of P2X7R on lym-phocytes compared to patients without arthritis (Z=-2.772,P=0.006).The expression of P2X7R on lymphocytes and CD19+ cell was significantly positively correlated with the SLEDAI score.Positive correlation with anti-β2GP Ⅰ in lymphocyteswas also found.Conclusion P2X7R may mediate the release of inflammatory cytokines involved in the pathogenesis of SLE,and may participate the development of arthritis,lupus nephritis and NPSLE in SLE patients.