Abstract: Objective To detect the activation of NF－κ B signaling pathway in peripheral blood mononuclear cells(PBMCs)of patients with systemic lupus erythematosus(SLE)and investigate its clinical significance. Methods Activation of NF－κ B was detected by electrophoretic mobility shift assay(EMSA),the expression of Iκ Bα protein and its phosphorylated products were detected by Western blot. Anti-dsDNA antibody,IgG and IgM in supernatant of PBMC culture were tested by ELISA. Results (1)Elevated activation of NF－κ B in PBMC of SLE patients was found when compared with the controls(P<0.05),and activation of NF－κ B in active SLE group was higher than that of inactive SLE group(P<0.05). (2)The expression of Iκ Bα in SLE group was lower than that of the control group(P<0.05),and Iκ Bα in active SLE group was lower than that of inactive SLE group(P<0.05).(3)Iκ Bα phosphorylated product in SLE group was higher than that in the control group,and the product in the active SLE group was increased compared with the inactive SLE group.(4)The activation of NF－κ B and Iκ Bα phosphorylated product had a positive correlation with the titer of anti-dsDNA antibody,IgG in the supernatant of PBMC culture and SLEDAI,respectively. Conclusions There are abnormal activation of NF－κ B signaling pathway in SLE. Detection of activation of NF－κ B signaling pathway in PBMC may be used as a predicator of SLE disease activity.

Key words: Lupus erythematosus,systemic, Leukocytes,mononuclear, NF-kappa B, I kappa Bα