| Assay Method Information | |
| | Measurement of A2A or A2B Binding Affinity Using SPA |
| Description: | Method (B): Binding affinity using SPA was conducted as follows. Test compounds (50 nL) were dispensed into individual wells of a 384-well OptiPlate™ well (Perkin Elmer) by Echo acoustic liquid transfer (Labcyte). 20 μL of 1.25 nM [3H] SCH58261 ((7-(2-phenylethyl)-5-amino-2-(2-furyl)-pyrazolo-[4,3-e]-1,2,4-triazolo[1,5-c]pyrimidine)) in DPBS assay buffer (Dulbecco's phosphate buffered saline without calcium and magnesium, ThermoFisher Scientific, Cat. No. A1285601) supplemented with 10 mM MgCl2 was added. A2A or A2B receptor-expressing membranes were incubated with 20 μg/mL adenosine deaminase (Roche, Cat. No. 10 102 105 001) for 15 min at room temperature. The receptor-expressing membranes were then combined with wheat germ agglutinin-coated yttrium silicate SPA beads (GE Healthcare, Cat. No. RPNQ0023) in a ratio of 1:1000 (w/w) and incubated for 30 min at room temperature. 30 μL of the membrane/bead mixture (0.25 μg and 25 μg per well respectively) were added to the 384-well OptiPlate™ well. To define total and non-specific binding, wells containing 1% DMSO or 1 μM CGS15943 (Tocris Bioscience, Cat. No. 1699) respectively were also included in the experiment. The plate was incubated for 1 h at room temperature with agitation. The assay plate was then incubated for an h to allow the beads to settle before data were collected using a TopCount (Perkin Elmer) scintillation counter. After normalization to total and non-specific binding, the percent effect at each compound concentration was calculated. The plot of percent effect versus the log of compound concentration was analyzed electronically using a 4-parameter logistic fit based on the Levenberg-Marquardt algorithm to generate IC50 values. |
| Affinity data for this assay | |
|---|---|
| If you find an error in this entry please send us an E-mail | |