A fluorescent ligand-binding alternative using Tag-lite® technology

J Biomol Screen. 2010 Dec;15(10):1248-59. doi: 10.1177/1087057110384611. Epub 2010 Oct 25.

Abstract

G-protein-coupled receptors (GPCRs) are crucial cell surface receptors that transmit signals from a wide range of extracellular ligands. Indeed, 40% to 50% of all marketed drugs are thought to modulate GPCR activity, making them the major class of targets in the drug discovery process. Binding assays are widely used to identify high-affinity, selective, and potent GPCR drugs. In this field, the use of radiolabeled ligands has remained so far the gold-standard method. Here the authors report a less hazardous alternative for high-throughput screening (HTS) applications by the setup of a nonradioactive fluorescence-based technology named Tag-lite(®). Selective binding of various fluorescent ligands, either peptidic or not, covering a large panel of GPCRs from different classes is illustrated, particularly for chemokine (CXCR4), opioid (δ, µ, and κ), and cholecystokinin (CCK1 and CCK2) receptors. Affinity constants of well-known pharmacological agents of numerous GPCRs are in line with values published in the literature. The authors clearly demonstrate that the Tag-lite binding assay format can be successfully and reproducibly applied by using different cellular materials such as transient or stable recombinant cells lines expressing SNAP-tagged GPCR. Such fluorescent-based binding assays can be performed with adherent cells or cells in suspension, in 96- or 384-well plates. Altogether, this new technology offers great advantages in terms of flexibility, rapidity, and user-friendliness; allows easy miniaturization; and makes it completely suitable for HTS applications.

MeSH terms

  • Animals
  • Cricetinae
  • Drug Evaluation, Preclinical / methods
  • Fluorescence
  • HEK293 Cells
  • High-Throughput Screening Assays / methods*
  • Humans
  • Ligands
  • Receptor, Cholecystokinin A / metabolism
  • Receptor, Cholecystokinin B / metabolism
  • Receptors, CXCR4 / metabolism
  • Receptors, G-Protein-Coupled / chemistry*
  • Receptors, G-Protein-Coupled / metabolism*
  • Receptors, Opioid / metabolism

Substances

  • Ligands
  • Receptor, Cholecystokinin A
  • Receptor, Cholecystokinin B
  • Receptors, CXCR4
  • Receptors, G-Protein-Coupled
  • Receptors, Opioid