title: Effects of peripheral cannabinoid receptor ligands on motility and polarization in neutrophil-like HL60 cells and human neutrophils.
abstract: The possible role of the peripheral cannabinoid receptor (CB2) in neutrophil migration was investigated by using human promyelocytic HL60 cells differentiated into neutrophil-like cells and human neutrophils isolated from whole blood. Cell surface expression of CB2 on HL60 cells, on neutrophil-like HL60 cells, and on human neutrophils was confirmed by flow cytometry. Upon stimulation with either of the CB2 ligands JWH015 and 2-arachidonoylglycerol (2-AG), neutrophil-like HL60 cells rapidly extended and retracted one or more pseudopods containing F-actin in different directions instead of developing front/rear polarity typically exhibited by migrating leukocytes. Activity of the Rho-GTPase RhoA decreased in response to CB2 stimulation, whereas Rac1, Rac2, and Cdc42 activity increased. Moreover, treatment of cells with RhoA-dependent protein kinase (p160-ROCK) inhibitor Y27632 yielded cytoskeletal organization similar to that of CB2-stimulated cells. In human neutrophils, neither JWH015 nor 2-AG induced motility or morphologic alterations. However, pretreatment of neutrophils with these ligands disrupted N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP)-induced front/rear polarization and migration and also substantially suppressed fMLP-induced RhoA activity. These results suggest that CB2 might play a role in regulating excessive inflammatory response by controlling RhoA activation, thereby suppressing neutrophil migration.
authors.affiliation: Division of Proteomics, Department of Genome Sciences, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan.
authors.forename: Rina
authors.initials: R
authors.lastname: Kurihara
authors.forename: Yumi
authors.initials: Y
authors.lastname: Tohyama
authors.forename: Satoshi
authors.initials: S
authors.lastname: Matsusaka
authors.forename: Hiromu
authors.initials: H
authors.lastname: Naruse
authors.forename: Emi
authors.initials: E
authors.lastname: Kinoshita
authors.forename: Takayuki
authors.initials: T
authors.lastname: Tsujioka
authors.forename: Yoshinao
authors.initials: Y
authors.lastname: Katsumata
authors.forename: Hirohei
authors.initials: H
authors.lastname: Yamamura
mesh_terms: D000199:Actins / Q000378:metabolism; D001095:Arachidonic Acids / Q000494:pharmacology; D002462:Cell Membrane / Q000378:metabolism; D002465:Cell Movement; D004247:DNA / Q000737:chemistry; D063388:Endocannabinoids; D005989:Glycerides / Q000494:pharmacology; D018922:HL-60 Cells; D006801:Humans; D008024:Ligands; D018375:Neutrophil Activation; D009504:Neutrophils / Q000378:metabolism*; D043882:Receptors, Cannabinoid / Q000737:chemistry*; D015398:Signal Transduction; D020742:rhoA GTP-Binding Protein / Q000737:chemistry*
chemical_list: D000199:Actins; D001095:Arachidonic Acids; D063388:Endocannabinoids; D005989:Glycerides; D008024:Ligands; D043882:Receptors, Cannabinoid; C094503:glyceryl 2-arachidonate; D004247:DNA; D020742:rhoA GTP-Binding Protein