Effects of IL-22 on rheumatoid arthritis fibroblast-like synoviocytes / 中国病理生理杂志

ABSTRACT

AIM:To determine the effects and mechanisms of interleukin-22 (IL-22) on the fibroblast-like sy-noviocytes ( FLSs) from rheumatoid arthritis ( RA) patients.METHODS:RA-FLSs were cultured by tissue culture meth-od.RA-FLSs were incubated with different concentrations of IL-22 (0,1,10,100μg/L) for 24 h, 48 h and 72 h.The cell viability was examined by CCK-8 assay.IL-22 at concentration of 10 μg/L was used to stimulate RA-FLSs for 24 h, and the change of cell cycle distribution was identified by flow cytometry.The effects of IL-22 at concentrations of 0, 1, 10, 100μg/L and/or STA-21 (a STAT3 inhibitor at concentrations of 0, 25, 50μmol/L) on the protein levels of Bcl-2 and p-STAT3 in the RA-FLSs were determined by Western blot.RESULTS:Compared with control group, stimulation of rhIL-22 at different concentrations for 24 h, 48 h and 72 h, the cells viabilityof RA-FLSs were obviously increased ( P<0.05 ) . After co-cultured with 10 μg/L rhIL-22 for 24 h, the percentages of RA-FLSs were obviously increased in the G2/M+S phase and decreased in the G0/G1 phase.At the same time, rhIL-22 increased, but STA-21 decreased the protein levels of Bcl-2 but p-STAT3 in the RA-FLSs obviously (P<0.05).Treatment with STAT3 inhibitor STA-21 reversed the effect of IL-22-induced Bcl-2 upregulation in the RA-FLSs ( P<0.01 ) .CONCLUSION: STAT3 is critical in the process of IL-22-induced Bcl-2 upregulation in RA-FLSs, indicating that IL-22 may play a role in the apoptosis of RA-FLSs.