Figure 2

ATR-107 behaves like a non-competitive antibody. Summarized results of ATR-107 inhibition on STAT3 phosphorylation in peripheral T (A) and B (B) cells induced by different amount of IL-21. Whole blood was pre-incubated with various amounts of ATR-107, as indicated on the graphs, for 30 minutes, followed by 1–1,000 ng/ml of IL-21 stimulation for 15 minutes. The reaction was stopped, and the RBC removed by adding the BD Lyse/fix buffer. The remaining cells were then washed, permeabilized and stained for pSTAT3. Shown are the means ± SE from 2–3 separate experiments. % of Max was defined as: (MFI – background) / (Max response – background) X 100. Same data was re-plotted with IL-21 at the x-axis (C, D).