Rapid identification of orexin receptor binding ligands using cell-based screening accelerated with magnetic beads.

We report here a simple and rapid method by which to screen one bead one compound libraries for highly specific ligands to cell surface proteins such as G protein-coupled receptors. This protocol, which harvests "hits" in a cell-based binding screen magnetically, eliminates the most tedious aspects of previously published bead screening techniques and allows millions of different compounds to be screened rapidly and cheaply. The method is demonstrated using the orexin receptor 1, which resulted in the isolation of moderate potency antagonists.