title: Functional expression of CCR1, CCR3, CCR4, and CXCR4 chemokine receptors on human platelets.
abstract: Platelets are known to contain platelet factor 4 and beta-thromboglobulin, alpha-chemokines containing the CXC motif, but recent studies extended the range to the beta-family characterized by the CC motif, including RANTES and Gro-alpha. There is also evidence for expression of chemokine receptors CCR4 and CXCR4 in platelets. This study shows that platelets have functional CCR1, CCR3, CCR4, and CXCR4 chemokine receptors. Polymerase chain reaction detected chemokine receptor messenger RNA in platelet RNA. CCR1, CCR3, and especially CCR4 gave strong signals; CXCR1 and CXCR4 were weakly positive. Flow cytometry with specific antibodies showed the presence of a clear signal for CXCR4 and weak signals for CCR1 and CCR3, whereas CXCR1, CXCR2, CXCR3, and CCR5 were all negative. Immunoprecipitation and Western blotting with polyclonal antibodies to cytoplasmic peptides clearly showed the presence of CCR1 and CCR4 in platelets in amounts comparable to monocytes and CCR4 transfected cells, respectively. Chemokines specific for these receptors, including monocyte chemotactic protein 1, macrophage inflammatory peptide 1alpha, eotaxin, RANTES, TARC, macrophage-derived chemokine, and stromal cell-derived factor 1, activate platelets to give Ca(++) signals, aggregation, and release of granule contents. Platelet aggregation was dependent on release of adenosine diphosphate (ADP) and its interaction with platelet ADP receptors. Part, but not all, of the Ca(++) signal was due to ADP release feeding back to its receptors. Platelet activation also involved heparan or chondroitin sulfate associated with the platelet surface and was inhibited by cleavage of these glycosaminoglycans or by heparin or low molecular weight heparin. These platelet receptors may be involved in inflammatory or allergic responses or in platelet activation in human immunodeficiency virus infection.
authors: Theodor Kocher Institute, University of Berne, Berne, Switzerland; and Serono Pharmaceutical Research Institute SA, Geneva, Switzerland. clemetson@tki.unibe.ch
authors: K J
authors: KJ
authors: Clemetson
authors: J M
authors: JM
authors: Clemetson
authors: A E
authors: AE
authors: Proudfoot
authors: C A
authors: CA
authors: Power
authors: M
authors: M
authors: Baggiolini
authors: T N
authors: TN
authors: Wells
mesh_terms: D000244:Adenosine Diphosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000031:analogs & derivatives* / Q000494:pharmacology; D000328:Adult; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism*; D015153:Blotting, Western; D020013:Calcium Signaling; D018925:Chemokines / Q000494:pharmacology; D019765:Chondroitin ABC Lyase / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D004792:Enzyme Precursors / Q000378:metabolism; D005246:Feedback; D005434:Flow Cytometry; D005786:Gene Expression Regulation; D006493:Heparin / Q000494:pharmacology; D019763:Heparin Lyase / Q000494:pharmacology; D006495:Heparin, Low-Molecular-Weight / Q000494:pharmacology; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D007527:Isoenzymes / Q000378:metabolism; D010446:Peptide Fragments / Q000494:pharmacology; D051966:Phospholipase C gamma; D010766:Phosphorylation / Q000187:drug effects; D010974:Platelet Aggregation / Q000187:drug effects / Q000502:physiology; D016133:Polymerase Chain Reaction; D011499:Protein Processing, Post-Translational / Q000187:drug effects; D011505:Protein-Tyrosine Kinases / Q000378:metabolism; D058919:Purinergic P2 Receptor Antagonists; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D054389:Receptors, CCR1; D054397:Receptors, CCR3; D054398:Receptors, CCR4; D019718:Receptors, CXCR4 / Q000096:biosynthesis* / Q000235:genetics; D019707:Receptors, Chemokine / Q000096:biosynthesis* / Q000235:genetics; D017452:Receptors, IgG / Q000378:metabolism; D018048:Receptors, Purinergic P2 / Q000502:physiology; D000072377:Syk Kinase; D013931:Thromboxanes / Q000096:biosynthesis; D014162:Transfection; D010738:Type C Phospholipases / Q000378:metabolism
chemical_list: C092108:2-propylthio-D-beta,gamma-difluoromethylene ATP; C515300:CCR1 protein, human; C515350:CCR3 protein, human; C515354:CCR4 protein, human; D018925:Chemokines; D004792:Enzyme Precursors; D006495:Heparin, Low-Molecular-Weight; D047908:Intracellular Signaling Peptides and Proteins; D007527:Isoenzymes; D010446:Peptide Fragments; D058919:Purinergic P2 Receptor Antagonists; D012333:RNA, Messenger; D054389:Receptors, CCR1; D054397:Receptors, CCR3; D054398:Receptors, CCR4; D019718:Receptors, CXCR4; D019707:Receptors, Chemokine; D017452:Receptors, IgG; D018048:Receptors, Purinergic P2; D013931:Thromboxanes; C082835:thrombin receptor peptide (42-47); D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D006493:Heparin; D011505:Protein-Tyrosine Kinases; C000606896:SYK protein, human; D000072377:Syk Kinase; D010738:Type C Phospholipases; D051966:Phospholipase C gamma; D019765:Chondroitin ABC Lyase; D019763:Heparin Lyase