title: Histamine-induced actin polymerization in human eosinophils: an imaging approach for histamine H4 receptor.
abstract: Image-based screening, a new and flexible tool in the drug discovery cascade, is amenable to many different targets. This article describes a particular use of the Cellomics ArrayScan in developing a functional screen for histamine H(4) receptor (H(4)R) antagonists that have potential utility in inflammatory diseases of the airways such as asthma, with H(4)R being expressed on a wide variety of immune cells including eosinophils. Exposure to histamine causes eosinophils to migrate from the bloodstream into the tissue where they contribute to inflammation. Migration is manifested through rearrangements of the actin cytoskeleton and phalloidin, a biological peptide, selectively binds F-actin over G-actin and can be used to detect these cytoskeletal changes mediating inflammatory function. A fluorescent conjugate of phalloidin was used to visualize histamine-induced actin polymerization in human eosinophils on the Cellomics ArrayScan. Inhibition of this phenomenon by commercially available histamine receptor antagonists was measured. The selective H(4)R antagonist JNJ7777120 inhibited histamine-induced actin polymerization in eosinophils most potently. This assay illustrates that this phenomenon is mediated through the H(4)R and that the image-based format has enhanced screening utility for identifying selective H(4)R antagonists over traditional flow cytometry methods.
authors.affiliation: Biomarkers & Translational Biology, Pfizer, Sandwich, Kent, United Kingdom. ruth.barnard@pfizer.com
authors.forename: Ruth
authors.initials: R
authors.lastname: Barnard
authors.forename: Adrian
authors.initials: A
authors.lastname: Barnard
authors.forename: Gary
authors.initials: G
authors.lastname: Salmon
authors.forename: Wai
authors.initials: W
authors.lastname: Liu
authors.forename: Sasha
authors.initials: S
authors.lastname: Sreckovic
mesh_terms: D000199:Actins / Q000737:chemistry*; D003599:Cytoskeleton / Q000378:metabolism; D004804:Eosinophils / Q000378:metabolism*; D005434:Flow Cytometry / Q000379:methods*; D006632:Histamine / Q000378:metabolism*; D006801:Humans; D007249:Inflammation; D020128:Inhibitory Concentration 50; D008954:Models, Biological; D010590:Phalloidine / Q000737:chemistry; D011108:Polymers / Q000737:chemistry; D043562:Receptors, G-Protein-Coupled / Q000737:chemistry* / Q000378:metabolism; D011968:Receptors, Histamine / Q000737:chemistry* / Q000378:metabolism; D000074040:Receptors, Histamine H4; D012680:Sensitivity and Specificity
chemical_list: D000199:Actins; C418607:HRH4 protein, human; D011108:Polymers; D043562:Receptors, G-Protein-Coupled; D011968:Receptors, Histamine; D000074040:Receptors, Histamine H4; D010590:Phalloidine; D006632:Histamine