Purpose: Among other reasons, the deteriorating global security situation and dangers associated with nuclear weapons have increased the need for deeper knowledge of the basic mechanisms involving the human immune system and ionizing radiation (IR). We conducted a review as to the effects of IR on thymic tissue, and particularly on the development of thymocytes and the T lymphocytes population in peripheral blood. Existing knowledge on this topic is based in part on national registers that store records concerning irradiated people. The majority of studies in this area, however, are based on experimental animal models. The main open question in this subject area regards the delayed effects of IR on thymus tissue, development of thymocytes, and subsequent impact on the immune system. Findings acquired to date on effects of IR are contributing to emerging fields such as immunotherapy, the objective of which is to support or activate natural immunity response. Methods: Recent research articles were reviewed regarding the influence of IR on thymus tissue and thymocytes development. Results: Differentiation and proliferation of thymocytes constitute a complex and sensitive process that is partially altered after irradiation, as are, too, the mechanisms for movement of early (derived from bone marrow) and derived (thymus derivatives) precursors. Disruption of these processes may lead to alteration of immune system function. Conclusions: Low doses (<200 mGy) may lead to changes in or disruption of functions of the thymus, thymocytes, and mechanisms of the immune system. The extent of IR’s influence is dependent not only on the individual’s radiosensitivity but also on his or her sex and age. With increasing absorbed IR dose, the risk of damage to thymus tissue and thymocytes in the organism rises and the extent of damage increases.

• MeSH
• dávka záření MeSH
• hematopoéza účinky záření   MeSH
• imunitní systém účinky záření   MeSH
• ionizující záření * MeSH
• lidé MeSH
• lymfocyty účinky záření   MeSH
• radiační expozice * škodlivé účinky   MeSH
• radiační účinky MeSH
• reiradiace MeSH
• thymocyty účinky záření   MeSH
• thymus účinky záření   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• práce podpořená grantem MeSH
• přehledy MeSH

The aim of the present study was to evaluate the biodosimetric potential of peripheral blood lymphocytes, particularly of T-cell subsets (null and T helper) and natural killer cells (NK), upon exposure to gamma irradiation (60Co) in vivo. For this purpose, the change in relative numbers of NK cells and T-lymphocyte subsets, as well as in the H2AX phosphorylation rate, were evaluated as potential early markers of the lymphocytic response to irradiation in vivo. These experiments were performed on a Large White Pig model. As a result, significant but not dose-dependent changes in the proportion of lymphocyte subpopulations (NK cells, null and T helper cells) were found after exposure to ionising radiation in vivo. On the other hand, circulating NK cells showed relatively higher radioresistance capacity when compared to the T-lymphocyte subsets; however, gamma-H2AX expression showed no significant difference between the evaluated lymphocyte subsets.

• MeSH
• buňky NK účinky záření   MeSH
• fenotyp MeSH
• fosforylace MeSH
• histony metabolismus   MeSH
• imunofenotypizace MeSH
• ionizující záření MeSH
• lymfocyty cytologie   MeSH
• poškození DNA MeSH
• prasata MeSH
• radioizotopy kobaltu farmakologie   MeSH
• radiometrie metody   MeSH
• T-lymfocyty - podskupiny účinky záření   MeSH
• záření gama MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Radiation therapy is one of the most common treatment strategies for thorax malignancies. One of the considerable limitations of this therapy is its toxicity to normal tissue. The lung is the major dose-limiting organ for radiotherapy. That is because ionizing radiation produces reactive oxygen species that induce lesions, and not only is tumor tissue damaged, but overwhelming inflammatory lung damage can occur in the alveolar epithelium and capillary endothelium. This damage may result in radiation-induced pneumonitis and/or fibrosis. While describing the lung response to irradiation generally, the main focus of this review is on cytokines and their roles and functions within the individual stages. We discuss the relationship between radiation and cytokines and their direct and indirect effects on the formation and development of radiation injuries. Although this topic has been intensively studied and discussed for years, we still do not completely understand the roles of cytokines. Experimental data on cytokine involvement are fragmented across a large number of experimental studies; hence, the need for this review of the current knowledge. Cytokines are considered not only as molecular factors involved in the signaling network in pathological processes, but also for their diagnostic potential. A concentrated effort has been made to identify the significant immune system proteins showing positive correlation between serum levels and tissue damages. Elucidating the correlations between the extent and nature of radiation-induced pulmonary injuries and the levels of one or more key cytokines that initiate and control those damages may improve the efficacy of radiotherapy in cancer treatment and ultimately the well-being of patients.

• MeSH
• chemokiny škodlivé účinky   MeSH
• cytokiny škodlivé účinky   MeSH
• lidé MeSH
• plíce patologie   účinky záření   MeSH
• poškození plic chemicky indukované   patologie   MeSH
• radiační poranění chemicky indukované   MeSH
• receptory chemokinů metabolismus   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

• Publikační typ
• abstrakt z konference MeSH

We examined the effect of epidermal growth factor (EGF) treatment in mice that received bone marrow transplantation (BMT) after 11 Gy whole-body irradiation. C57Bl/6 mice were divided into three treatment groups: 0 Gy; 11 Gy ((60)Co, single dose, 0.51 Gy/min) with BMT (5 × 10(6) bone marrow cells isolated from green fluorescent protein syngeneic mice, 3-4 h postirradiation); and 11 Gy with BMT and EGF (2 mg/kg applied subcutaneously 1, 3 and 5 days postirradiation). Survival data were collected. Bone marrow, peripheral blood count and cytokines, gastrointestine and liver parameters and migration of green fluorescent protein-positive cells were evaluated at 63 days postirradiation. Epidermal growth factor increased survival of irradiated animals that received BMT from 10.7 to 85.7% at 180 days postirradiation. In the BMT group, we found changes in differential bone marrow and blood count, plasma cytokine levels, gastrointestinal tissues and liver at 63 days postirradiation. These alterations were completely or in some parameters at least partially restored by epidermal growth factor. These findings indicate that epidermal growth factor, administered 1, 3 and 5 days postirradiation in combination with bone marrow transplantation, significantly improves long-term prognosis.

• MeSH
• apoptóza účinky léků   účinky záření   MeSH
• bezpečnost MeSH
• časové faktory MeSH
• celotělové ozáření škodlivé účinky   MeSH
• cytokiny krev   MeSH
• epidermální růstové faktory farmakologie   MeSH
• kostní dřeň účinky léků   imunologie   účinky záření   MeSH
• mitóza účinky léků   účinky záření   MeSH
• myši MeSH
• počet buněk MeSH
• radiační poranění krev   farmakoterapie   patologie   terapie   MeSH
• slezina účinky léků   patologie   účinky záření   MeSH
• střeva účinky léků   patologie   účinky záření   MeSH
• transplantace kostní dřeně * MeSH
• velikost orgánu účinky léků   účinky záření   MeSH
• vztah dávky záření a odpovědi MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH