Fig. S1.
P2C2–Fab antibody fragment characterization. (A) Binding of P2C2–Fab to 5-HT2B receptor as measured by ELISA in the presence and absence (apo) of ERG. Data points are shown as mean ± SEM of three experiments performed in triplicate. (B) Effect of point mutations on P2C2–Fab binding as measured by ELISA. Data points are shown as mean ± SEM of three experiments (two experiments for P202A mutant) performed in triplicate. (C) Flow cytometry data with P2C2–Fab and TRex CHO stable cell line expressing wild-type 5-HT2B (green) and Δ44–5-HT2B (blue) receptor. Uninduced cells (gray) did not show any binding to P2C2–Fab. (D) No nonspecific binding of secondary antibody to cells expressing the receptor was observed. (E) No binding of P2C2–Fab to the cells expressing 5-HT2C was observed. (F) Expression of 5-HT2C was confirmed by using an anti-5-HT2C antibody (Abcam).