title: Effect of in vitro cyclosporin. A treatment on human natural and antibody-dependent cell-mediated cytotoxicity.
abstract: Concentrations of 0.1 to 10.0 micrograms of cyclosporin A (Cy A) per ml do not directly inhibit the lysis of 51Cr-labeled K562 target cells by human peripheral blood natural killer (NK) cells nor of antibody-coated chicken red blood cells by antibody-dependent cellular cytotoxicity (ADCC) effector cells. Pretreatment of effector cells with Cy A for 18 hr still failed to affect NK or ADCC effector function. However, induction of NK cell activity by overnight pretreatment of effector cells by polyinosinate-polycytidylate (PolyIC) is inhibited by as little as 1 micrograms of Cy A per ml. The mechanism of inhibition may involve a direct effect of Cy A on "induced" or "activated" NK cells or inhibition of the release of Poly IC-induced interferon from lymphocytes.
mesh_terms: D000920:Antibody-Dependent Cell Cytotoxicity / Q000187:drug effects*; D003524:Cyclosporins / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D007369:Interferon Inducers / Q000494:pharmacology; D007694:Killer Cells, Natural / Q000187:drug effects* / Q000276:immunology; D008214:Lymphocytes / Q000276:immunology; D011070:Poly I-C / Q000494:pharmacology
chemical_list: D003524:Cyclosporins; D007369:Interferon Inducers; D011070:Poly I-C