The screening and functional characterization of novel ligands for G-Protein Coupled Receptors (GPCR) remains a key focus in drug discovery. Of late, an increasing awareness of the subtleties of receptor signaling and potential for ligand bias requires multiple endpoints to be monitored for the same screening campaign. In addition, efforts to reduce costs and improve efficiency of screening are always a key consideration for any screening campaign. In this webinar, we describe a duplexed assay for the Histamine H1 receptor using the PathHunter β-arrestin clonal cell line from DiscoverX. We have adapted existing assay protocols to monitor intracellular calcium signaling in real time along with the recruitment of β-arrestin to the Histamine H1 receptor, from the same well on a plate. We discuss protocol development and successful implementation of the final assay with this multiplexing approach, through data presented on Histamine H1 agonists and antagonist pharmacology. This duplexed assay clearly demonstrates an overall increase in screening efficiency and a total reduction in cost for running similar screening, lead optimization, and characterization programs for GPCR drug discovery.
 
Learning Objective 1 : Screening approaches for GPCR drug discovery
 
Learning Objective 2 :Creating a duplexed assay to monitor Calcium and β-arrestin in a single well