To investigate the expression levels of T follicular helper (Tfh) with different subsets in patients with rheumatoid arthritis (RA) and their serum interleukin-6 (IL-6), interleukin-17 (IL-17), transforming growth factor-β (TGF-β) and matrix metalloproteinase 3 (MMP-3) contents.
The medical records of 45 RA patients in the Department of Rheumatology and Immunology in the First Affiliated Hospital of Chengdu Medical College from January 2016 to April 2018 were retrospectively analyzed. They were divided into the RA high activity group (24 cases, group A) (DAS28 score ≥ 5.0) and RA low activity group (21 cases, group B) (3.2 < DAS28 score < 5.0). At the same time, 20 healthy subjects were selected as a control group. Flow cytometry was used to detect the expression levels of Tfh1, Tfh2 and Tfh17, enzyme-linked immunosorbent assay to detect serum IL-6, IL-17, IL-21 and MMP-3 concentrations. The correlation of Tfh cells with IL-6, IL-17, IL-21 and MMP-3 was analyzed.
Those of peripheral blood mononuclear cell (PBMC) Tfh2 and Tfh17 cells were significantly higher in group A than those in group B (p < 0.05). Compared with the control group, the concentrations of serum IL-6, IL-17 and MMP-3 significantly increased (p < 0.001), but that of serum TGF-β markedly decreased in group A and group B (p < 0.01). The concentrations of serum IL-6, IL-17 and MMP-3 were remarkably higher in group A than those in group B (p < 0.001), but that of serum TGF-β was significantly lower in group A than that in group B (p < 0.001). The expression level of PBMC Tfh2 cells, PBMC Tfh17 cells was positively correlated with serum IL-6, IL-17 and MMP-3. The expression levels of Tfh2 and Tfh17 cells are positively correlated with serum IL-6, IL-17 and MMP-3 concentrations, negatively correlated with serum TGF-β concentration.
Tfh2 and Tfh17 are expected to be new targets for immunotherapy in RA patients.