Fig. 2

Knee osteoarthritis (KOA) synovial fluid (SF) monocytes/macrophages (MΦs) are the most abundant SF leukocytes (SFLs) and have different prevalence to those in the circulation. a Frequency of SFL and peripheral blood mononuclear cell (PBMC) (N = 40) populations. No statistical analysis is shown for neutrophils. b MΦ subset ratios, in PBMC and SF MΦs (N = 40). a and b Wilcoxon signed test (paired) was used. P values shown are corrected for multiple comparisons. Box plots indicate median with interquartile range for box and Tukey-style whiskers. Lines between boxplots indicate significant differences, with adjusted p value shown on top. White dots with white box represent data from PBMCs; black dots with gray box represent data from SFLs. NK, natural killer