Figure 6.

Janus kinase (JAK)/STAT inhibitors blocked Interleukin (IL)-7-mediated osteoclast formation from peripheral blood mononuclear cells (PBMCs) and synovial fluid mononuclear cells (SFMCs). PBMCs from healthy individuals (A,C) and SFMCs from rheumatoid arthritis patients (B,D) were cultured with M-CSF (20 ng/mL), RANKL (50 ng/mL), or IL-7 (2 ng/mL) in the presence or absence of tofacitinib [5 µM, (A,B)] or signal transducer and activator of transcription 5 (STAT5) inhibitor [CAS 285986-31-4, 50 µM, (C,D)] for 10 days, replacing the medium at 3-day intervals with fresh cytokines and osteoprotegerin. Tartrate-resistant acid phosphatase (TRAP) staining and enumeration were performed as described in Figure 1. Representative images and quantification of TRAP⁺ cells are shown. Results are representative of three or six independent experiments. Bars represent the mean and p values were obtained using the unpaired two-tailed Student’s t-test.