Figure 4. Ameliorated joint inflammation in Fra-1^ΔMx arthritic mice.

K/BxN arthritis was induced in Fra-1 mutant mice and their respective control mice. Healthy or arthritic mice were analyzed 10 days after serum transfer. (A) Fra-1 mRNA levels in paws of healthy and arthritic control mice (n = 4). (B) Fra-1 mRNA levels in stromal cells (CD11b^–), neutrophils (CD11b⁺Ly6G⁺), monocytes (CD11b⁺Ly6C⁺), and macrophages (CD11b⁺F4/80⁺) sorted from arthritic Fra-1^ΔMx, Fra-1^ΔLysM, and control littermate mice. (C) Arthritis scores of control, control^ΔMx, and Fra-1^ΔMx mice and quantification of AUC. (D) Quantification and representative images of paw volume ascertained from in vivo MRI analysis of healthy, arthritic Fra-1^ΔMx and arthritic control mice. Graph points indicate individual mice. Data are shown as mean values, and the error bars represent SEM. *P < 0.05; **P < 0.01; ***P < 0.001, Student’s t test (A and B) or ANOVA (C and D).