title: Interferon-Beta combined with interleukin-2 restores human natural cytotoxicity impaired in vitro by ionizing radiations.
abstract: It is well known that ionizing radiations induce a marked downregulation of antigen-dependent and natural immunity for a prolonged period of time. This is due, at least in part, to radiation-induced apoptosis of different lymphocyte subpopulations, including natural killer (NK) cells. Aim of this study was to investigate the capability of Beta Interferon (β-IFN) and Interleukin-2 (IL2), alone or in combination, to restore the functional activity of the natural immune system. Mononuclear cells (MNCs) obtained from intact or in vitro irradiated human peripheral blood were treated in vitro with β-IFN immediately before or at the end of the 4-day treatment with IL2. Time-course analysis was performed on the NK activity, the total number and the apoptotic fraction of CD16+ and CD56+ cells, the 2 main NK effector cell subpopulations. The results indicate that radiation-induced impairment of natural cytotoxicity of MNC could be successfully antagonized by the β-IFN+IL2 combination, mainly when exposure to β-IFN preceded IL2 treatment. This radioprotective effect is paralleled by lower levels of radiation-induced apoptosis and increased expression of the antiapoptotic Bcl-2 protein. Since natural immunity can play a significant role in antitumor host's resistance, these results could provide the rational basis for a cytokine-based pharmacological strategy able to restore immune responsiveness and to afford possible therapeutic benefits in cancer patients undergoing radiotherapy.
authors: Department of Neuroscience, Chair of Pharmacology, School of Medicine, University of Rome Tor Vergata, Rome, Italy.
authors: Ornella
authors: O
authors: Franzese
authors: Maria
authors: M
authors: Tricarico
authors: Giuseppe
authors: G
authors: Starace
authors: Rita
authors: R
authors: Pepponi
authors: Laura
authors: L
authors: Bonmassar
authors: Andrea
authors: A
authors: Cottarelli
authors: Maria Pia
authors: MP
authors: Fuggetta
mesh_terms: D017209:Apoptosis / Q000187:drug effects / Q000276:immunology / Q000528:radiation effects; D019002:CD56 Antigen / Q000276:immunology; D045744:Cell Line, Tumor; D003602:Cytotoxicity, Immunologic / Q000187:drug effects* / Q000276:immunology / Q000528:radiation effects*; D058851:GPI-Linked Proteins / Q000276:immunology; D005720:Gamma Rays; D006801:Humans; D007113:Immunity, Innate / Q000187:drug effects* / Q000276:immunology / Q000528:radiation effects*; D016899:Interferon-beta / Q000276:immunology / Q000494:pharmacology*; D007376:Interleukin-2 / Q000276:immunology / Q000494:pharmacology*; D020014:K562 Cells; D007694:Killer Cells, Natural / Q000187:drug effects / Q000276:immunology / Q000528:radiation effects; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000276:immunology / Q000528:radiation effects; D016131:Lymphocyte Subsets / Q000187:drug effects / Q000276:immunology / Q000528:radiation effects; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000276:immunology; D017452:Receptors, IgG / Q000276:immunology
chemical_list: D019002:CD56 Antigen; C428200:FCGR3B protein, human; D058851:GPI-Linked Proteins; D007376:Interleukin-2; C522918:NCAM1 protein, human; D019253:Proto-Oncogene Proteins c-bcl-2; D017452:Receptors, IgG; D016899:Interferon-beta