Longitudinal Profiling of Rheumatoid Arthritis

Peripheral blood and synovial tissue samples were collected before treatment (baseline (FU0)), at week 4 (follow-up 1 (FU1)) and at week 16 (follow-up 2 (FU2)) after rituximab treatment, as described before.12 14 (link) For some patients the week 16 post-treatment peripheral blood sample was not available and peripheral blood samples collected at week 24 were analysed instead. Peripheral blood mononuclear cells (PBMCs) were isolated from total blood using Ficoll separation (GE Healthcare, ref 17-1440-02) and cryopreserved in liquid nitrogen until RNA isolation. Synovial tissue biopsies were collected by needle arthroscopy as previously described15 (link) from an inflamed knee as judged by the treating physician and cryopreserved in liquid nitrogen until RNA isolation.