Fig. 3

M-MDSCs derived from patients with AS suppress T cell responses. a Depletion of MDSCs enhanced T cell function. PBMCs or PBMCs with MDSC depletion (PBMC-MDSC depletion) from fresh peripheral blood of AS patients were stimulated with CD3/CD28, and proliferation of T cells was examined by CFSE dilution. Left panels: representative flow cytometry data from one individual; right panel: results of stimulated samples from six individuals. b CD3⁺ T cell from patients at ankylosing spondylitis patients were stimulated with anti-CD3/CD28, co-cultured with M-MDSCs from the same donors at different ratios for 3d, and T cell proliferation was evaluated by CFSE labeling; unstimulated T cells were used as a negative control. Left panels: representative flow cytometry data from one individual; right panel: results from five individuals. c Production of IFN-γ by T cells in supernatants from panel (b) was measured by ELISA. Means and SD are shown; n = 6. d Co-culture of M-MDSCs-T cell (1:2) experiments as in panel (b) were performed, with or without Transwells. ^*P < 0.05; ^**P < 0.01, compared with controls by unpaired t test. AS ankylosing spondylitis, CFSEcarboxyfluorescein succinimidyl ester, IFN interferon, M-MDSCs monocytic myeloid-derived suppressor cells, PMN-MDSC polymorphonuclear myeloid-derived suppressor cells