2ME2 Inhibits Angiogenesis in the Antibody-Induced Model of Rheumatoid Arthritis. On study day 21, right and left hind paws were fixed in formalin, sectioned and stained for vWF, a marker of angiogenesis and endothelial cell proliferation. Abundant staining for vWF factor was evident in sections from mice treated with vehicle control (A). In contrast, treatment of mice with 100 mg/kg/day of 2ME2 completely blocked vWF staining (B). Magnification = 10×.