title: Expression and functional activity of the IL-8 receptor type CXCR1 and CXCR2 on human mast cells.
abstract: To further elucidate mechanisms involved in mast cell accumulation at sites of cutaneous inflammation, we have studied the ability of human leukemic mast cells (HMC-1 cells) to express functionally active IL-8 receptors. Expression of mRNA for both types of IL-8 receptors (CXCR1 and CXCR2) was demonstrated by PCR and of both proteins by flow cytometry. Binding and competition studies with 125I-labeled IL-8 and its homologue melanoma growth stimulating activity (125I-labeled MGSA) revealed two specific binding sites for IL-8, K1 = 1.1 x 10(11) M(-1) and K2 = 5 x 10(7) M(-1); and for MGSA, K1 = 2.8 x 10(10) M(-1) and K2 = 5 x 10(7) M(-1). This finding was supported by a dose-dependent rise of cytosolic free calcium concentration ([Ca2+]i) induced by both chemokines and to a lesser extent by the homologue neutrophil-activating peptide-2 (NAP-2). A significant migratory response of human leukemic mast cells (HMC-1) was observed with all three chemokines at a range from 10(-8) M to 10(-9) M. Moreover, the formation of cellular F-actin was induced in a rapid, dose-dependent fashion, with a maximally 1.7-fold increase at 10(-7) M. Using postembedding immunoelectron microscopy, we could show the expression of CXCRI on the cytoplasmatic membrane of isolated human skin mast cells whereas CXCR2 was located in mast cell-specific granules. These findings demonstrate for the first time the functional expression of both types of IL-8 receptors on human mast cells, suggesting a role for their ligands during mast cell activation and recruitment.
authors.affiliation: Department of Dermatology, Charité, Campus Virchow Klinikum, Humboldt Universität, Berlin, Germany.
authors.forename: U
authors.initials: U
authors.lastname: Lippert
authors.forename: M
authors.initials: M
authors.lastname: Artuc
authors.forename: A
authors.initials: A
authors.lastname: Grützkau
authors.forename: A
authors.initials: A
authors.lastname: Möller
authors.forename: A
authors.initials: A
authors.lastname: Kenderessy-Szabo
authors.forename: D
authors.initials: D
authors.lastname: Schadendorf
authors.forename: J
authors.initials: J
authors.lastname: Norgauer
authors.forename: K
authors.initials: K
authors.lastname: Hartmann
authors.forename: R
authors.initials: R
authors.lastname: Schweitzer-Stenner
authors.forename: T
authors.initials: T
authors.lastname: Zuberbier
authors.forename: B M
authors.initials: BM
authors.lastname: Henz
authors.forename: S
authors.initials: S
authors.lastname: Krüger-Krasagakes
mesh_terms: D000199:Actins / Q000378:metabolism; D015703:Antigens, CD / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology / Q000648:ultrastructure; D001667:Binding, Competitive; D002118:Calcium / Q000378:metabolism; D002465:Cell Movement / Q000187:drug effects; D054360:Chemokine CXCL1; D019743:Chemokines, CXC; D002630:Chemotactic Factors / Q000378:metabolism / Q000494:pharmacology; D005434:Flow Cytometry; D006133:Growth Substances / Q000378:metabolism / Q000494:pharmacology; D018922:HL-60 Cells; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins; D016209:Interleukin-8 / Q000378:metabolism* / Q000494:pharmacology; D007457:Iodine Radioisotopes; D008407:Mast Cells / Q000378:metabolism* / Q000502:physiology / Q000648:ultrastructure; D010455:Peptides / Q000494:pharmacology; D016133:Polymerase Chain Reaction; D011485:Protein Binding; D012333:RNA, Messenger / Q000096:biosynthesis; D019707:Receptors, Chemokine / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology; D018123:Receptors, Interleukin / Q000096:biosynthesis* / Q000235:genetics / Q000502:physiology / Q000648:ultrastructure; D023062:Receptors, Interleukin-8A; D023063:Receptors, Interleukin-8B; D012867:Skin / Q000378:metabolism / Q000648:ultrastructure; D014407:Tumor Cells, Cultured; D001620:beta-Thromboglobulin
chemical_list: D000199:Actins; D015703:Antigens, CD; C475829:CXCL1 protein, human; D054360:Chemokine CXCL1; D019743:Chemokines, CXC; D002630:Chemotactic Factors; D006133:Growth Substances; D036341:Intercellular Signaling Peptides and Proteins; D016209:Interleukin-8; D007457:Iodine Radioisotopes; C061615:PPBP protein, human; D010455:Peptides; D012333:RNA, Messenger; D019707:Receptors, Chemokine; D018123:Receptors, Interleukin; D023062:Receptors, Interleukin-8A; D023063:Receptors, Interleukin-8B; D001620:beta-Thromboglobulin; C009862:connective tissue-activating peptide; D002118:Calcium