Fig. 1.

sXBP1 expression in PBMC. (A) XBP1 splicing was determined by PCR, using primers that amplify both unspliced and spliced mRNA species. RA-ACT1 and 2 (RA patients with active disease); OA1- and OA2-osteoarthritis patients; RA-REM1 and 2 (RA patients in remission); HC, healthy control. (B) sXBP1 mRNA levels were determined by qRT-PCR and expressed as relative to levels of GAPDH. Data are shown as median with interquartile range. Statistical analysis of variance between different of groups was performed using the Kruskal–Wallis test and Dunn's Multiple Comparison Test was used to compare all pairs of data. (* = p < 0.05). (C) sXBP1 protein expression in PBMC was analysed by flow cytometry. Expression levels are shown as median fluorescence intensity (MFI) on the y-axis. Statistical significance was determined using non-parametric Mann–Whitney U test.