LAUSR

The involvement of histamine H4 receptor (H4R) in immune cells chemotaxis and mediator release makes it an attractive target for the treatment of inflammation disorders. A decade of medicinal chemistry efforts has led to several promising ligands, although the chemical structures described so far possesses a singular limited diversity. We report here the discovery of novel structures, belonging to completely different scaffolds. The virtual screening was planed as a two-steps process. First, using a "scout screening" methodology, we have experimentally probed the H4R ligand binding site using a small size chemical library with very diverse structures, and identified a hit that further assist us in refining a raw 3D homology model. Second, the refined 3D model was used to conduct a widened virtual screening. This two-steps strategy proved to be very successful, both in terms of structural diversity and hit rate (23%). Moreover, the hits have high affinity for the H4R, with most potent ligands in the nanomolar range.