The Mechanism of Radiation-Induced Interphase Death of Lymphoid Cells: A New Hypothesis

• Published in: Radiation research 1990-07, Vol.123 (1), p.17-21
• Main Authors: L. Kh. Eidus, Yu. N. Korystov, Dobrovinskaja, O. R., Shaposhnikova, V. V.
• Format: Article
• Language: English
• Subjects: AMINES; ANIMAL CELLS; ANIMALS; AROMATICS; AZO COMPOUNDS; AZO DYES; B lymphocytes; Biological and medical sciences; BIOLOGICAL EFFECTS; BIOLOGICAL FUNCTIONS; BIOLOGICAL MATERIALS; BIOLOGICAL RADIATION EFFECTS; BLOOD; BLOOD CELLS; BODY FLUIDS; CELL CONSTITUENTS; Cell death; CELL KILLING; CELL NUCLEI; Cell Nucleus - drug effects; Cell Nucleus - radiation effects; Cell Survival - drug effects; Cell Survival - radiation effects; COBALT ISOTOPES; Cobalt Radioisotopes; CONNECTIVE TISSUE CELLS; Cytochalasin B - pharmacology; Dose-Response Relationship, Radiation; DOSE-RESPONSE RELATIONSHIPS; DYES; ELECTROMAGNETIC RADIATION; FUNCTIONS; GAMMA RADIATION; Gamma Rays; Hematologic and hematopoietic diseases; HYDROXY COMPOUNDS; IN VITRO; In Vitro Techniques; Interphase; Interphase - drug effects; Interphase - radiation effects; IONIZING RADIATIONS; Irradiation; ISOTOPES; Killing; LEUKOCYTES; LYMPHOCYTES; Male; MAMMALS; MATERIALS; Medical sciences; Mercaptoethanol - pharmacology; Monensin - pharmacology; NAPHTHOLS; Natural killer cells; ORGANIC ACIDS; ORGANIC COMPOUNDS; ORGANIC NITROGEN COMPOUNDS; ORGANIC SULFUR COMPOUNDS; PHENOLS; Phenylmethylsulfonyl Fluoride - pharmacology; Radiation dosage; RADIATION EFFECTS; RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT; RADIATIONS; RATS; Rats, Inbred Strains; RODENTS; SOMATIC CELLS; SULFONIC ACIDS; SURVIVAL TIME; T lymphocytes; T-Lymphocytes - drug effects; T-Lymphocytes - radiation effects; THYMOCYTES; TRYPAN BLUE; VERTEBRATES 560120 > Radiation Effects on Biochemicals, Cells, & Tissue Culture
• ISSN: 0033-7587; 1938-5404
• DOI: 10.2307/3577652

The interphase death of irradiated rat thymocytes depends on their concentration during postirradiation incubation. The kinetics of pycnosis and cell death determined with the trypan blue exclusion test in the samples with the highest cell concentration (1-2× 107 cells/ ml) is consistent with the data available in the literature, whereas the samples with the lowest concentration ($2\times 10^{5}\ \text{cells}/{\rm ml}$) undergo almost no pycnosis and death after irradiation with doses up to 50 Gy. On the basis of these results, we suggest a new mechanism of interphase death involving an interaction between irradiated thymocytes and the fraction of thymus cells possessing cytocidal activity. The observed correlation between the cytocidal activity and interphase death of thymocytes from animals of different ages favors our mechanism. It was found that the inhibitors which prevent the conjugation of killer cells and their targets do not influence interphase death, while the substances which block the secretion of cytotoxic factors or their action on the target membrane do protect from interphase death. Thus we suggest that the irradiation activates the killer cells to secrete some cytotoxic factors which induce pycnosis and interphase death of thymocytes.