Our GLP1R fluorescent antagonist shows high affinity for glucagon-like peptide-1 receptor (pEC50 = 7.5 for GLP1R) modulating the receptor by orthosteric antagonism. The efficacy and potency of LUXendin645 (CELT-112) as a GLP1R ligand was confirmed by inhibition of GLP-1-stimulated cAMP levels in SNAP-GLP1R:HEK293 cells. LUXendin645 (CELT-112) has been used in a variety of imaging applications, including widefield/confocal/2-photon microscopy in live and fixed mammalian cells and tissue. Using TR-FRET, LUXendin645 was used in GLP1R competitive binding experiments and in GLP1R trafficking and recycling studies.
*2º Image: Widefield image of live CHO-K1:SNAP-GLP1R cells labeled with 200 nM LUXendin645. Scale bar = 40 micrometer.