title: Expression of protectin (CD59) in human melanoma and its functional role in cell- and complement-mediated cytotoxicity.
abstract: Immunohistochemical and/or indirect immunofluorescence analysis with monoclonal antibody (MAb) H19 demonstrated the expression of protectin (CD59) in 54 surgically removed metastatic melanoma lesions and on 8 out of 12 melanoma cell lines. CD59 expression had a low degree of intra- and intertumor heterogeneity. SDS-PAGE analysis showed that the molecular weight of CD59 expressed on melanoma cells is about 20 kDa. Treatment of melanoma cells with 5U/ml of phosphatidylinositol-specific phospholipase C completely abolished cell-surface expression of CD59. Interferon-gamma and/or tumor necrosis factor-alpha or phorbol 12-myristate 13-acetate neither modulated the expression of CD59 by melanoma cells nor influenced the amounts of CD59-specific mRNA. F(ab')2 fragments of anti-CD59 MAb YTH53. I did not inhibit the lysis of melanoma cells by allogeneic natural killer (NK) cells or lymphokine-activated killer (LAK) cells. In contrast, the whole Ig molecule of MAb HI9 or YTH53.I significantly (p < 0.05) enhanced NK-cell-mediated lysis of melanoma cells, suggesting the induction of antibody-dependent cell-mediated cytotoxicity. Lastly, masking of CD59 by MAb YTH53.I or its F(ab')2 fragments significantly (p < 0.05) enhanced, in a dose-dependent fashion, the lysis of anti-GD3-sensitized melanoma cells by homologous complement. These data demonstrate that CD59 expressed by human melanoma cells might regulate host-tumor interaction by protecting neoplastic cells from complement-mediated lysis.
authors.affiliation: Advanced Immunotherapy Unit, Istituto Nazionale di Ricovero e Cura a Carattere Scientifico-Centro di Riferimento Oncologico, Aviano, Italy.
authors.forename: L I
authors.initials: LI
authors.lastname: Brasoveanu
authors.forename: M
authors.initials: M
authors.lastname: Altomonte
authors.forename: A
authors.initials: A
authors.lastname: Gloghini
authors.forename: E
authors.initials: E
authors.lastname: Fonsatti
authors.forename: S
authors.initials: S
authors.lastname: Coral
authors.forename: A
authors.initials: A
authors.lastname: Gasparollo
authors.forename: R
authors.initials: R
authors.lastname: Montagner
authors.forename: I
authors.initials: I
authors.lastname: Cattarossi
authors.forename: C
authors.initials: C
authors.lastname: Simonelli
authors.forename: A
authors.initials: A
authors.lastname: Cattelan
mesh_terms: D000911:Antibodies, Monoclonal / Q000494:pharmacology; D000920:Antibody-Dependent Cell Cytotoxicity / Q000187:drug effects; D015703:Antigens, CD / Q000032:analysis / Q000276:immunology*; D018957:CD59 Antigens; D003169:Complement Inactivator Proteins / Q000032:analysis / Q000276:immunology*; D016207:Cytokines / Q000494:pharmacology; D003602:Cytotoxicity, Immunologic / Q000276:immunology*; D005455:Fluorescent Antibody Technique; D006801:Humans; D007114:Immunization; D007128:Immunoglobulin Fragments / Q000494:pharmacology; D007150:Immunohistochemistry; D015979:Killer Cells, Lymphokine-Activated / Q000276:immunology*; D007694:Killer Cells, Natural / Q000276:immunology*; D008545:Melanoma / Q000737:chemistry / Q000276:immunology* / Q000556:secondary; D008562:Membrane Glycoproteins / Q000032:analysis / Q000276:immunology*; D043265:Phosphatidylinositol Diacylglycerol-Lyase; D054801:Phosphoinositide Phospholipase C; D010727:Phosphoric Diester Hydrolases / Q000494:pharmacology; D012333:RNA, Messenger / Q000032:analysis; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D018957:CD59 Antigens; D003169:Complement Inactivator Proteins; D016207:Cytokines; D007128:Immunoglobulin Fragments; D008562:Membrane Glycoproteins; D012333:RNA, Messenger; D010727:Phosphoric Diester Hydrolases; D054801:Phosphoinositide Phospholipase C; D043265:Phosphatidylinositol Diacylglycerol-Lyase; D013755:Tetradecanoylphorbol Acetate