title: Differential effects of dibutyryl cyclic adenosine monophosphate and simple sugars on NK and LAK activities suggesting differences of their cytotoxic mechanism.
abstract: The increase of intracellular cyclic AMP levels suppresses the cytotoxic activities of lymphocytes and monosaccharides interfere with cell to cell and cell to cytokine interactions, and these effects on natural killer (NK)/antibody-dependent cell-mediated cytotoxicity (ADCC) and lymphokine activated killer (LAK) activities were examined. Dibutyryl cyclic AMP markedly suppressed NK, IL-2-augmented NK and ADCC activities in a dose-dependent manner but not previously induced LAK activity. Induction of LAK was inhibited. Dibutyryl cyclic GMP had no effect. Addition of mannose 6-phosphate and galactose 6-phosphate strongly inhibited NK and ADCC activities, but not LAK activity. These results suggest that the lytic mechanism for NK and ADCC activity is different from that of LAK activity.
authors.affiliation: Department of Pediatrics, Tokyo Medical and Dental University, Japan.
authors.forename: S
authors.initials: S
authors.lastname: Takagi
authors.forename: M
authors.initials: M
authors.lastname: Inada
authors.forename: H
authors.initials: H
authors.lastname: Okawa
authors.forename: J
authors.initials: J
authors.lastname: Yata
mesh_terms: D000920:Antibody-Dependent Cell Cytotoxicity / Q000187:drug effects; D003994:Bucladesine / Q000494:pharmacology*; D003602:Cytotoxicity, Immunologic; D004305:Dose-Response Relationship, Drug; D005695:Galactosephosphates / Q000494:pharmacology; D006801:Humans; D007694:Killer Cells, Natural / Q000187:drug effects / Q000276:immunology*; D008360:Mannosephosphates / Q000494:pharmacology
chemical_list: D005695:Galactosephosphates; D008360:Mannosephosphates; C027693:mannose-6-phosphate; D003994:Bucladesine