Decreased Stat3 activation is correlated with angiostatic activity. (A) Western blot analysis (n = 2) of cell lysates of 10 ng/mL bFGF stimulated SVEC4-10 after 5- or 30-minute incubation with IL-2, IL-21, or anginex. After 30 minutes, IL-2-, IL-21-, and anginex-treated cells showed decreased Stat3 phosphorylation (P-Stat3). (B) Western blot analysis (n = 1) of cell lysates of bFGF stimulated primary mouse endothelial cells after 30 minutes with IL-21, IL-2, or anginex.