Double-antiangiogenic protein reduces pathologic findings, infiltration of F4/80+ macrophages and vessel formation in collagen-induced arthritis. (A) and (B) Representative sections of ankle joints stained with hematoxylin and eosin and Safranin O, respectively (bars = 500 μm). (C) and (D) Representative images of synovium stained with F4/80 and CD31 (bars = 50 μm). (E) Quantitative scores of pathological abnormalities. (F) Mean number of infiltrating F4/80+ macrophages. (G) Mean number of CD31+ blood vessels in the synovium. DAAP: Double-antiangiogenic protein; Tie2: Tyrosine kinase with immunoglobulin and epidermal growth factor homology domain 2; VEGF: Vascular endothelial growth factor. The joint tissues were sampled at day 40. Values are mean ± SE, n = 18 to 20 for each group. *P < 0.05, **P < 0.01 vs. Fc; #P < 0.05, ##P < 0.01 vs. VEGF-Trap.
Hah et al. Arthritis Research & Therapy 2013 15:R85 doi:10.1186/ar4265