Figure 1.
(a) FITC-labeled RTX binding to Daudi cells with two increasing concentrations of 20 and 60 nM during the association phase, dissociation was measured in plain medium. (red, n = 4) Data was fitted to a 1:1 binding model (black). (b) Interaction Map analysis for RTX binding to Daudi cells, input data from all four binding curves in (a) was used for the calculation. The analysis results in two defined interaction components that mainly differ in their binding stability (x-axis). The more stable component is dominating with the tested RTX concentrations, indicated by warmer colors in the plot. (c) Daudi cells were incubated with 9 nM FITC-labeled RTX and binding recorded (black). After 10, 30, 60 and 90 min, 9 nM of RTX labeled with a quencher was added to the incubation solution (red). Gaps in the binding curves indicate the time point when the incubation solution was changed to cell culture medium not containing any RTX. All displayed curves were normalized in signal height by setting the baseline to 0% and the signal at the timpoint of the first quencher addition (10 min) to 100%. Target occupancy was calculated using the Bmax value obtained from fitting a 1:1 model to the black curve, containing only 9 nM FITC-RTX.