NanoBRET binding assay for histamine H2 receptor ligands using live recombinant HEK293T cells

Lukas Grätz, Katharina Tropmann, Merlin Bresinsky, Christoph Müller, Günther Bernhardt, Steffen Pockes
2020 Scientific Reports  
Fluorescence/luminescence-based techniques play an increasingly important role in the development of test systems for the characterization of future drug candidates, especially in terms of receptor binding in the field of G protein-coupled receptors (GPCRs). In this article, we present the establishment of a homogeneous live cell-based BRET binding assay for the histamine H2 receptor with different fluorescently labeled squaramide-type compounds synthesized in the course of this study.
more » ... his study. Py-1-labeled ligand 8 (UR-KAT478) was found to be most suitable in BRET saturation binding experiments with respect to receptor affinity (pKd = 7.35) and signal intensity. Real-time kinetic experiments showed a full association of 8 within approximately 30 min and a slow dissociation of the ligand from the receptor. Investigation of reference compounds in BRET-based competition binding with 8 yielded pKi values in agreement with radioligand binding data. This study shows that the BRET binding assay is a versatile test system for the characterization of putative new ligands at the histamine H2 receptor and represents a valuable fluorescence-based alternative to canonical binding assays.
doi:10.1038/s41598-020-70332-3 pmid:32764682 fatcat:a5c4oy4ward2fb47reyu7xenjm