title: Differential protective action of cytokines on radiation-induced apoptosis of peripheral lymphocyte subpopulations.
abstract: It is established that soluble factors involved in cell growth can prevent apoptosis of hematolymphoid cell lines in factor-deprived situations. The present study investigates the possible protective effects of various cytokines on radiation-induced apoptosis of apparently quiescent lymphocyte subpopulations. The exposure to gamma-irradiation resulted in appreciable apoptotic changes in all of lymphocyte subpopulations. Natural killer (NK) cells were the most radiosensitive, whereas CD8+ T and B cells showed weaker susceptibility to radiation and CD4+ T cells were relatively radioresistant. The radiation-induced apoptosis in NK cells was significantly inhibited by IL-2. In addition to IL-2, IL-4 and IL-7 rescued both CD4+ and CD8+ T cells from radiation-induced cell death. The viability of B cells was maintained by the presence of IL-4 but not others in culture. Furthermore, we conclude that the protective effect by each cytokine on radiation-induced apoptosis might be partly attributed to enhancement of cellular expression of bcl-2 protein.
authors.affiliation: Department of Pediatrics, School of Medicine, Kanazawa University, Ishikawa, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Seki
authors.forename: K
authors.initials: K
authors.lastname: Iwai
authors.forename: H
authors.initials: H
authors.lastname: Kanegane
authors.forename: A
authors.initials: A
authors.lastname: Konno
authors.forename: K
authors.initials: K
authors.lastname: Ohta
authors.forename: K
authors.initials: K
authors.lastname: Ohta
authors.forename: A
authors.initials: A
authors.lastname: Yachie
authors.forename: N
authors.initials: N
authors.lastname: Taniguchi
authors.forename: T
authors.initials: T
authors.lastname: Miyawaki
mesh_terms: D000328:Adult; D017209:Apoptosis / Q000276:immunology / Q000528:radiation effects*; D004249:DNA Damage / Q000502:physiology; D005434:Flow Cytometry; D006801:Humans; D066298:In Vitro Techniques; D007378:Interleukins / Q000502:physiology*; D016131:Lymphocyte Subsets / Q000528:radiation effects*; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis; D019253:Proto-Oncogene Proteins c-bcl-2
chemical_list: D007378:Interleukins; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2