title: Complement activation by HIV-1-infected target cells enhances IL-2-stimulated but not unstimulated ADCC activity mediated by peripheral blood mononuclear cells.
abstract: The goal of this study was to determine whether deposition of complement C3 breakdown products on the surface of HIV-infected target cells could augment the levels of antibody-dependent cellular cytotoxicity (ADCC) mediated by peripheral blood mononuclear cells (PBMC). Although C3 was deposited on the surface of infected cells in the presence of anti-HIV antibody from infected persons, no increase in the levels of ADCC mediated by freshly isolated PBMC was seen with either infected H9 or CEM-NKr target cells. However, a significant increase in ADCC was observed due to deposition of C3 on target cells with IL-2-stimulated effector cells. These results show that C3 deposition on target cells can increase ADCC cytotoxicity under certain conditions. Complement may thus contribute to destruction of HIV-infected cells through this mechanism in vivo, although these experiments suggest that specific antibody is the major targeting molecule for ADCC.
authors.affiliation: Department of Immunology/Microbiology, Rush Medical School, Chicago, Illinois 60612, USA.
authors.forename: I
authors.initials: I
authors.lastname: Sereti
authors.forename: G T
authors.initials: GT
authors.lastname: Spear
mesh_terms: D000920:Antibody-Dependent Cell Cytotoxicity / Q000187:drug effects; D002460:Cell Line; D003167:Complement Activation / Q000187:drug effects / Q000502:physiology*; D003601:Cytotoxicity Tests, Immunologic; D015658:HIV Infections / Q000276:immunology*; D015497:HIV-1 / Q000276:immunology*; D006801:Humans; D007376:Interleukin-2 / Q000494:pharmacology*; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000378:metabolism* / Q000821:virology*; D008213:Lymphocyte Activation
chemical_list: D007376:Interleukin-2