Patent ID: 7232659

Claim:
A method comprising evaluating the relative G protein receptor agonism, antagonism or inactivity of a compound for a G protein coupled receptor (GPCR) in a single sample by a flow cytometric process comprising the steps of (a) providing a sample suspension containing a detectable GPCR, a set of G protein beads which will form a ternary complex with said detectable GPCR in the presence of an agonist or partial agonist, and a set of ligand beads which will bind to said detectable GPCR, said set of G-protein beads comprising epitope-recognizing beads having an epitope bearing heterotrimeric G protein bound thereto and wherein at least one of said set of G protein beads and said set of ligand beads are detectable colored beads; (b) mixing said sample suspension with said compound; and (c) detecting the formation or absence of formation of a complex between said compound and said detectable GPCR, wherein a GPCR antagonist prevents binding of said detectable GPCR to said G protein beads by preventing ternary complex formation and prevents binding of said detectable GPCR to said ligand bead; a GPCR agonist allows binding of said detectable GPCR to said G protein beads by forming a ternary complex but prevents binding of said detectable GPCR to said ligand bead; and an inactive compound prevents binding of said detectable GPCR to said G protein beads by not promoting ternary complex formation but allows binding of said detectable GPCR to said ligand bead.