title: Evidence that phospholipase-C-dependent, calcium-independent mechanisms are required for directional migration of T-lymphocytes in response to the CCR4 ligands CCL17 and CCL22.
abstract: Macrophage-derived chemokine [CC chemokine ligand 22 (CCL22)] and thymus- and activation-regulated chemokine (CCL17) mediate cellular effects, principally by binding to their receptor CC chemokine receptor 4 (CCR4) and together, constitute a multifunctional chemokine/receptor system with homeostatic and inflammatory roles within the body. This study demonstrates that CCL22 and CCL17 stimulate pertussis toxin-sensitive elevation of intracellular calcium in the CEM leukemic T cell line and human peripheral blood-derived T helper type 2 (Th2) cells. Inhibition of phospholipase C (PLC) resulted in the abrogation of chemokine-mediated calcium mobilization. Chemokine-stimulated calcium responses were also abrogated completely by the inhibition of inositol 1,4,5-trisphosphate [Ins(1,4,5)P3] receptor-mediated calcium release. Chemotactic responses of CEM and human Th2 cells to CCL17 and CCL22 were similarly abrogated by inhibition of PLC and inhibition of novel, Ca2+-independent/diacylglycerol-dependent protein kinase C (PKC) isoforms. Inhibition of Ins(1,4,5)P3 receptor-mediated calcium release from intracellular stores had no effect on chemotactic responses to CCR4 ligands. Taken together, this study provides compelling evidence of an important role for PLC and diacylglycerol-dependent effector mechanisms (most likely involving novel PKC isoforms) in CCL17- and CCL22-stimulated, directional cell migration. In this regard, CCL22 stimulates phosphatidylinositol-3 kinase-independent phosphorylation of the novel delta isoform of PKC at threonine 505, situated within its activation loop--an event closely associated with increased catalytic activity.
authors.affiliation: Department of Pharmacy & Pharmacology, University of Bath, Claverton Down, Bath, Avon, UK BA2 7AY.
authors.forename: Darran G
authors.initials: DG
authors.lastname: Cronshaw
authors.forename: Andreas
authors.initials: A
authors.lastname: Kouroumalis
authors.forename: Richard
authors.initials: R
authors.lastname: Parry
authors.forename: Adam
authors.initials: A
authors.lastname: Webb
authors.forename: Zarin
authors.initials: Z
authors.lastname: Brown
authors.forename: Stephen G
authors.initials: SG
authors.lastname: Ward
mesh_terms: D000098:Acetophenones / Q000494:pharmacology; D001578:Benzopyrans / Q000494:pharmacology; D002118:Calcium / Q000502:physiology; D015220:Calcium Channels / Q000502:physiology; D020013:Calcium Signaling / Q000187:drug effects / Q000502:physiology; D020134:Catalytic Domain; D045744:Cell Line, Tumor / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D054414:Chemokine CCL17; D054422:Chemokine CCL22; D019742:Chemokines, CC / Q000235:genetics / Q000502:physiology*; D002633:Chemotaxis / Q000187:drug effects / Q000502:physiology*; D002867:Chromones / Q000494:pharmacology; D004075:Diglycerides / Q000502:physiology; D004963:Estrenes / Q000494:pharmacology; D006801:Humans; D007211:Indoles / Q000494:pharmacology; D015544:Inositol 1,4,5-Trisphosphate / Q000502:physiology; D053496:Inositol 1,4,5-Trisphosphate Receptors; D015459:Leukemia-Lymphoma, Adult T-Cell / Q000473:pathology; D009025:Morpholines / Q000494:pharmacology; D037342:Pertussis Toxin / Q000494:pharmacology; D019869:Phosphatidylinositol 3-Kinases / Q000502:physiology; D043265:Phosphatidylinositol Diacylglycerol-Lyase / Q000037:antagonists & inhibitors / Q000502:physiology*; D000081082:Phosphoinositide-3 Kinase Inhibitors; D010766:Phosphorylation; D010769:Phosphothreonine / Q000737:chemistry; D011499:Protein Processing, Post-Translational / Q000187:drug effects / Q000502:physiology*; D011758:Pyrroles / Q000494:pharmacology; D011760:Pyrrolidinones / Q000494:pharmacology; D054398:Receptors, CCR4; D019707:Receptors, Chemokine / Q000502:physiology*; D018160:Receptors, Cytoplasmic and Nuclear / Q000037:antagonists & inhibitors / Q000502:physiology; D011993:Recombinant Fusion Proteins / Q000494:pharmacology; D013601:T-Lymphocytes / Q000166:cytology / Q000187:drug effects*; D018418:Th2 Cells / Q000166:cytology / Q000187:drug effects
chemical_list: D000098:Acetophenones; D001578:Benzopyrans; D002118:Calcium; D015220:Calcium Channels; D054414:Chemokine CCL17; D054422:Chemokine CCL22; D019742:Chemokines, CC; D002867:Chromones; D004075:Diglycerides; D004963:Estrenes; D007211:Indoles; D015544:Inositol 1,4,5-Trisphosphate; D053496:Inositol 1,4,5-Trisphosphate Receptors; D009025:Morpholines; D037342:Pertussis Toxin; D019869:Phosphatidylinositol 3-Kinases; D043265:Phosphatidylinositol Diacylglycerol-Lyase; D000081082:Phosphoinositide-3 Kinase Inhibitors; D010769:Phosphothreonine; D011758:Pyrroles; D011760:Pyrrolidinones; D054398:Receptors, CCR4; D019707:Receptors, Chemokine; D018160:Receptors, Cytoplasmic and Nuclear; D011993:Recombinant Fusion Proteins; C011439:1,2-diacylglycerol; C106230:CCL17 protein, human; C515482:CCL22 protein, human; C515354:CCR4 protein, human; C506926:ITPR1 protein, human; C506927:ITPR2 protein, human; C060229:1-(6-((3-methoxyestra-1,3,5(10)-trien-17-yl)amino)hexyl)-1H-pyrrole-2,5-dione; C085989:Ro 32-0432; C085911:2-(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one; C085746:rottlerin