CXCR4, or C-X-C motif chemokine receptor 4, is a key member of the GPCR family that plays a critical role in immune system regulation, cell migration, and tissue homeostasis and is implicated in various pathological processes, including HIV entry, cancer metastasis, and inflammatory diseases, making it a significant therapeutic target. Traditional methods for studying GPCRs often fail to adequately capture the full spectrum of signaling mechanisms of specific receptors like CXCR4, which primarily couples to adenylyl cyclase activity and intracellular cAMP production.

The Screen Quest™ Live Cell Chemokine (C-X-C motif) receptor CXCR4 cAMP Assay Service Pack is specifically designed for real-time, high-throughput monitoring of intracellular cAMP changes associated with CXCR4 activation using transfected cell lines and Calbryte™ 520 wash-free calcium fluorescence detection methods. Unlike conventional assays that require cell lysis, this assay preserves cellular integrity, enabling both temporal and spatial resolution of specific signaling events associated with CXCR4. This assay employs cell lines transfected to express CXCR4 along with a promiscuous G-protein Gα16. The Gα16 protein allows CXCR4, which primarily signals through the cAMP pathway, to also couple to Gq signal transduction and mobilize intracellular calcium. Activation of CXCR4 by specific ligands, such as SDF-1 (stromal cell-derived factor-1), can be detected using calcium-sensitive dyes like Calbryte™ 520 AM, Cal-520® AM, Fluo-8® AM, Fluo-4™ AM, or corresponding no-wash calcium kits. The inclusion of CXCR4 and Gα16 co-expression ensures robust calcium signaling for reliable assay performance.

This service pack provides all necessary components for precise measurement of CXCR4-mediated cAMP changes using FLIPR, FDSS, or equivalent fluorescence microplate readers. It is an ideal tool for studying non-Gq protein-coupled CXCR4 activity, enabling researchers to explore CXCR4 signaling pathways and evaluate potential therapeutic compounds targeting this receptor.