Role of NK-22 cells and interleukin-22-related molecules in proliferation of fibroblast- like synoviocytes in patients with rheumatoid arthritis
REN Jie
ZHOU Yi
WU Huixia
DAI Taoli
ZHU Lihua
Abstract：Objective To investigate the role of natural killer-22 (NK-22) cells in the synovial fluid in the proliferation of fibroblast-like synoviocytes (FLS) in patients with rheumatoid arthritis (RA) and explore the possible signal pathway involved. Methods NK-22 cells in the SF of RA patients were sorted by flow cytometry. NK-22 cells were cultured for two weeks and the purity was detected by flow cytometry before stimulation with 20 ng/ml phorbol 12-myristate 13-acetate and 0.5 μmol/L ionomycin for 4 h. The level of interleukin-22 (IL-22) in the culture medium supernatant was then measured with ELISA. The proliferation of FLS in the presence of the culture supernatant of NK-22 cells was assessed with MTT assay at 24, 48 and 72 h, and the effect of IL-22 antibody on FLS proliferation was also observed. Real-time PCR and Western blotting were used to detect Stat3 mRNA and p-Stat3 protein levels, respectively, in the FLS exposed to rhIL-22 and AG490. Results NK-22 cells were successfully sorted by flow cytometry with a purity exceeding 90%. The levels of IL-22 in the supernatant of NKp44+NK cell culture averaged 1273.42±254.48 pg/ml. The FLS proliferated rapidly 24, 48, and 72 h after the addition of culture supernatant of NK-22 cells (P<0.05). IL-22 antibody obviously inhibited the proliferation of FLS induced by NK-22 cell culture supernatant (P<0.05). Exposure of the FLS to rhIL-22 obviously increased cellular Stat3 expression levels, which were significantly lowered by the addition of AG490 (P<0.05). Conclusion NK-22 cells in the SF of RA patients can produce high concentrations of IL-22 to promote the proliferation of FLS through the STAT3 signal pathway.
Keywords：rheumatoid arthritisnatural killer-22 cellsinterlukin-22signal transduction and activator of transcription 3
Publication Date：2014-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：5( 20-24 )