The CD8+ natural killer (NK) subpopulation has recently been identified as a fast and reliable biodosimetric indicator within human peripheral blood mononuclear cells (PBMC) in vitro. In irradiated and subsequently cultivated PBMC, a decrease of the relative number of intact CD3-CD8+ lymphocytes 16 and 48 h after treatment has allowed for estimating the received dose in the range of 0 - 10 Gy and lethal/sublethal dose discrimination, respectively. Here we show that suitable biodosimeters can also be found in the peripheral blood B-cell compartment. Multiparameter flow cytometric analysis of irradiated and subsequently cultivated human PBMC revealed that both the CD27+ and CD21- B-cell subpopulations can be used as biodosimeters and the CD19+CD27+ lymphocytes have proved useful for retrospective determination of the received dose in the range of 0 - 6 Gy. In addition, several CD19+ lymphocyte subsets characterized by co-expression of CD21, CD27 and CD38 have been shown to bear biodosimetric potential, too. However, when important parameters like the original size within the CD19+ compartment, its radiation-induced changes and data variation had been taken into account, the CD27+ subpopulation proved superior to the other B-cell subpopulations and subsets. It appears that, in the dose range of 0 - 6 Gy, the relative decrease of CD27+ B lymphocytes provides more sensitive and reliable data than that of CD8+ NK-cells due mainly to lower data variation. In contrast to CD27+ B-cells, the proportions of CD27+ subpopulations of T-cells were not affected by irradiation. We have also proposed a simple experimental protocol based on full blood cultivation and three-color CD27/CD3/CD19 immunophenotyping as a time-saving and inexpensive approach for practical biodosimetric evaluations on simple, three-to-four color flow cytometers.

• Klíčová slova
• B-cells, CD27, Biodosimetric marker, ?-irradiation,
• MeSH
• annexin A5 metabolismus   MeSH
• antigeny CD27 fyziologie   MeSH
• antigeny CD38 fyziologie   MeSH
• B-lymfocyty fyziologie   účinky záření   MeSH
• biologické markery MeSH
• fenotyp MeSH
• financování organizované MeSH
• fosfatidylseriny metabolismus   MeSH
• lidé MeSH
• monocyty fyziologie   MeSH
• podskupiny lymfocytů fyziologie   MeSH
• průtoková cytometrie MeSH
• receptory buněčného povrchu metabolismus   MeSH
• receptory komplementu 3d metabolismus   MeSH
• separace buněk MeSH
• vztah dávky záření a odpovědi MeSH
• záření gama MeSH
• Check Tag
• lidé MeSH

The aim of our work was to evaluate peripheral blood lymphocyte subsets as in vitro indicators of the received dose of ionizing radiation (biodosimetric markers) in the range of 3-20 Gy and to determine the appropriate time interval, during which a dose-dependent induction of apoptosis occurs upon ? irradiation. In lymphocyte subsets characterized by double color surface immunophenotyping, four-color flow cytometry was used for visualizing cell death-associated increase in superficial phosphatidylserine exposure and cytoplasmic membrane permeability by fluorinated Annexin V and propidium iodide, respectively. No differences between sham-treated and lethal dose (7 Gy)-irradiated samples were observed upon 6 h cultivation in vitro. Ten and 18 h later, about 50 % of lymphocytes were apoptotic, but only the minority of them was in the late apoptotic phase. The only difference in radioresistance of the CD4+CD8- and CD4- CD8+ lymphocyte subsets was seen upon 2-day cultivation when huge depletion of intact cells and prevalence of the late apoptotic population became obvious. A dose-dependence study in 16 and 48 h cultures confirmed the effectiveness of major T cell subsets as biodosimetric indicators. On the other hand, the minor CD8+ subset of natural killer (NK) cells has been identified as a radiosensitive lymphocyte population the disappearance of which correlated with the received dose. We demonstrated that the CD3-CD8+ NK subset can be used as a lethal/sublethal dose discriminator to 16 h cultivation. In addition, our data indicate that two-day cultivation followed by CD3/CD8 expression analysis in an intact lymphocyte population may provide a clue for low dosage biodosimetry.

• MeSH
• apoptóza genetika   účinky záření   MeSH
• buňky NK fyziologie   účinky záření   MeSH
• CD8-pozitivní T-lymfocyty fyziologie   účinky záření   MeSH
• financování vládou MeSH
• interpretace statistických dat MeSH
• ionizující záření MeSH
• lidé MeSH
• průtoková cytometrie metody   využití   MeSH
• radiometrie metody   využití   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• srovnávací studie MeSH

• MeSH
• financování organizované MeSH
• Publikační typ
• abstrakty MeSH

Gastrointestinal form is the second stage of acute radiation syndrome (ARS) with a threshold dose of 8 Gy in man. It represents an absolutely lethal clinical-pathological unit, necrohemorrhagic enteritis and proctocolitis, with unknown causal therapy. Elk-1 is a protein acting as a transcription factor activating specified genes. The purpose of our study was to examine the expression of phospho-Elk-1 in irradiated jejunum and transversal colon of rats with radiation-induced enterocolitis and to assess the importance of this transcriptional factor as a biodosimetric marker of radiation-induced enteropathy. The laboratory rats were randomly divided into 21 groups, 10 animals per group, and irradiated with whole body ?-irradiation of 1, 5, 10, 15, and 20 Gy. Samples of jejunum and transversal colon were taken 24, 48, 72, and 96 hours later, immunohistochemically stained, and the phospho-Elk-1 expression was examined using computer image analysis. A group of 10 shamirradiated animals was used as control. Significantly increased expression of phospho-Elk-1 in rat jejunum has been found in all time intervals after irradiation by sublethal doses of 1 and 5 Gy, whereas after the irradiation by lethal doses, the expression of phospho-Elk-1 in rat jejunum varied considerably. Significantly increased expression of phospho-Elk-1 in transversal colon has also been found in the first days after irradiation by sublethal doses of 1 and 5 Gy. After irradiation by lethal doses, tere was no uniform pattern of the changes in the expression of phospho-Elk- 1 in rat transversal colon. The detection of phospho-Elk-1 might be considered as a suitable and very sensitive biodosimetric marker of radiation-induced injury of small and large intestine. According to our knowledge, this is the first study on the phospho-Elk-1 expression in irradiated jejunum and transversal colon in the rat.

• Klíčová slova
• Radiation-induced entero-colitis, Phospho-Elk-1 expression, Biodosimetric marker,
• MeSH
• akutní radiační syndrom etiologie   metabolismus   MeSH
• biologické markery metabolismus   MeSH
• časové faktory MeSH
• celotělové ozáření MeSH
• enterokolitida etiologie   metabolismus   MeSH
• experimentální radiační poranění etiologie   metabolismus   MeSH
• fosforylace MeSH
• jejunum metabolismus   účinky záření   MeSH
• kolon metabolismus   účinky záření   MeSH
• krysa rodu rattus MeSH
• potkani Wistar MeSH
• protein Elk-1 s doménou ets metabolismus   MeSH
• upregulace MeSH
• vztah dávky záření a odpovědi MeSH
• záření gama MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH

The integrity of the human genome is constantly threatened by exogenous or endogenous genotoxic agents that cause DNA damage. The ionizing radiation (IR)-induced DNA double-strand breaks (DSBs) are considered as the most deleterious forms of DNA damage which could lead to genomic instability and to cancer development, if left unrepaired. The DNA damage response (DDR) is comprised of a network of proteins that cooperate to regulate cell cycle progression and repair of DNA lesions. Our understanding of molecular basis of repair processes and of functions of repair proteins, as well as understanding of chromatin modifications may provide new possibilities in improvement of cancer management. Phosphorylation of histone variant H2AX at serine 139 (γ-H2AX) and formation of γ-H2AX repair foci seems to be the most sensitive DNA damage marker in the chromatin flanking the free DNA double-stranded ends in DSBs. Monitoring of γ-H2AX levels can serve for early indication of cancer development, as biomarker of cancer therapy efficiency or as a biodosimetric marker of radiation exposure.

• MeSH
• biologické markery MeSH
• chromatin genetika   metabolismus   MeSH
• DNA vazebné proteiny genetika   metabolismus   MeSH
• DNA účinky záření   MeSH
• dvouřetězcové zlomy DNA účinky záření   MeSH
• financování organizované MeSH
• fosforylace MeSH
• fosfoserin metabolismus   MeSH
• histony genetika   metabolismus   MeSH
• ionizující záření MeSH
• jaderné proteiny genetika   metabolismus   MeSH
• lidé MeSH
• nádory diagnóza   MeSH
• oprava DNA MeSH
• tyrosin metabolismus   MeSH
• vazba proteinů MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• přehledy MeSH

Riziko akutního ozáření větší části populace stoupá a s ním i potřeba vyvíjet nové metody, které by mohly poskytnout rychlé posouzení obdržených dávek za použití moderních vysokokapacitních technologií. Současně vzrůstá i zájem o vývoj nových biomarkerů umožňujících kategorizaci ozářených osob, které by mohly být použity v epidemiologických studiích, a umožnily korelovat odhadované přijaté dávky s následným dopadem na zdraví pacienta. K tomu napomáhají rovněž aktuální poznatky v oblasti radiační genomiky, metabolomiky a proteomiky. Ačkoli většina studií, které poskytly mnoho užitečných informací o biomarkerech expozice ionizujícímu záření, byla prováděna na zvířecích modelech, nejdůležitějšími testy zůstávají studie prováděné na pacientech, zejména onkologických. Pro predikci účinku záření lze použít různé biologický materiály, ideální se pro tento účel zdají být plazmatické proteiny. Z řady kandidátních markerů je velmi slibná ferredoxin-reduktáza (FDXR), která byla v několika biodozimetrických studiích potvrzena jak na úrovni lidského genu, tak proteinu.

The increased risk of acute large-scale radiation exposure of the population underlies the necessity to develop new methods that could provide a rapid assessment of the doses received while using modern high-throughput technologies. At the same time, there is a growing interest in discovering new biomarkers enabling the categorization of irradiated individuals that could be used in epidemiological studies to correlate the estimated absorbed doses with the consequent impact on patient's health. The aim of this study was to summarize the current literature on biological dosimetry, specifically ionizing radiation-responsive biomarkers. We briefly describe current knowledge in the field of radiation genomics, metabolomics, and proteomics. Although the majority of studies that provided a plethora of useful information were conducted in animal models, oncological patients remain the crucial experimental model. The authors describe various biological materials that could be potentially used to predict the effect of ionizing radiation. Plasma proteins appear to be ideal for this purpose. Out of many candidate markers, the ferredoxin reductase (FDXR) seems to be promising, as it has been confirmed in several biodosimetric studies at the level of both human gene and protein.

• Klíčová slova
• biodozimetrie,
• MeSH
• biologické markery analýza   MeSH
• exprese genu MeSH
• ionizující záření MeSH
• lidé MeSH
• metabolomika MeSH
• poškození DNA * účinky záření   MeSH
• proteomika MeSH
• radiační expozice * analýza   MeSH
• radiační genomika MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• práce podpořená grantem MeSH
• přehledy MeSH

Při podezření na expozici ionizujícím zářením se u osob provádí vyšetření pomocí biodozimetrických metod. Změny v chromozomech umožňují detekovat míru expozice, předvídat stupeň poškození a rozhodnout o léčení. Kromě toho byla prokázána korelace mezi zvýšenou hladinou chromozomálních aberací po expozici genotoxickým faktorům a zvýšeným rizikem rakoviny. Biodozimetrických metod existuje celá řada, ale záleží na množství ozářených osob, laboratorních podmínkách, senzitivitě a časovém faktoru, který test je nejvhodnější. Mikrojaderný test je jedním z metod volby, protože výsledky mohou být známy do 48 až 72 hodin po odběru krve a je dostatečně citlivým ukazatelem dávky ionizujícího záření. Mikrojaderný test periferních lymfocytů je standardní biodozimetrická metoda, kterou lze použít jak v případě radiačních nehod, tak i monitoringu profesního ozáření osob. Byl vyvinut Fenechem a Morleym v roce 1985 a jeho principem je detekce malých acentrických chromozomálních fragmentů, které zůstanou mimo jádro během buněčného dělení. Tato mikrojádra jsou v cytoplazmě mimo hlavní dceřiná jádra. Mikrojádra mohou obsahovat jak celé chromozomy, tak i pouze jejich části.

Examinations based on biodosimetric methods are implemented in the case of suspect exposure of persons to ionizing radiation. Changes in chromosomes make it possible to detect the level of the exposure, predict the degree of the damage and make decisions on the treatment. In addition, a correlation was demonstrated between enhanced levels of chromosomal aberrations after the exposure to genotoxic factors and increased risk of cancer disease. There are a number of biodosimetric methods, but their choice depends on the number of persons exposed, laboratory conditions, sensitivity and time factor. The test of micronuclei is one of the methods of choice, since the results can be known as soon as within 48 to 72 hours after sampling the blood and the results are a sufficiently sensitive parameter indicating the ionizing radiation dose. The text of peripheral lymphocyte micronuclei is a standard biodosimetric method, which may be employed in the case of radiation accidents as well as in the monitoring of the occupational exposure of persons. It was developed by Fenech and Morley in 1985 and is based on the detection of small acentric chromosomal fragments, which remain beyond the nucleus in the course of the cell division. These micronuclei are present in the cytoplasm beyond the main daughter nuclei. The micronuclei can contain whole chromosomes as well as their parts only

• Klíčová slova
• biodozimetrie, mikrojaderně-centromerový test,
• MeSH
• biologické markery krev   MeSH
• biotest metody   přístrojové vybavení   MeSH
• cytogenetické vyšetření metody   MeSH
• DNA účinky záření   MeSH
• financování organizované MeSH
• hybridizace in situ fluorescenční metody   MeSH
• ionizující záření MeSH
• lymfocyty účinky záření   MeSH
• mikrojaderné testy metody   MeSH
• monitorování radiace metody   přístrojové vybavení   MeSH
• radiační poranění diagnóza   krev   MeSH
• radiometrie metody   MeSH
• Publikační typ
• přehledy MeSH

The aim of our study was to examine the in vivo expression of p21 and expression and activation of ATF-2, c-Myc, and CREB in rat peripheral blood mononuclear cells (PBMC) after whole body γ-irradiation and to assess its contribution to biodosimetry. For Western blot experiments, male Wistar rats were whole-body irradiated by a single dose of 0, 0.5, 1, 3, and 5 Gy (60 Co, 1 m, 0.7 Gy/min). As a positive control, leukaemic MOLT-4 cells were used. For ELISA experiments, male Wistar rats were whole-body irradiated by a single dose of 0, 1, 2, 3, 4, and 5 Gy (60 Co, 1 m, 0.6 Gy/min). Blood samples were taken 4 h after the irradiation and PBMC were isolated using centrifugation on Histopaque-1077. Expressions of p21, ATF-2, phospho-ATF-2Thr69/71 , c-Myc, phospho-c-MycThr-58/Ser62 , CREB, and phospho-CREBSer133 were measured using Western blot method. Expression of p21 was also quantified using ELISA. We observed increase of p21 expression in rat PBMC 4 h after irradiation. According to ELISA, p21 levels increased 2.0-, 3.1-, 5.5-, 3.0-, and 3.1fold after irradiation by 1, 2, 3, 4, and 5 Gy, respectively. We did not detect any expression or activation of ATF-2, c-Myc and CREB. Protein p21 could be considered as a perspective biodosimetric marker of clinically significant irradiation (≥1 Gy) in vivo in unstimulated PBMC.

• MeSH
• aktivační transkripční faktory * MeSH
• biologické markery krev   MeSH
• časové faktory MeSH
• celotělové ozáření MeSH
• ELISA MeSH
• inhibitor p21 cyklin-dependentní kinasy metabolismus   účinky záření   MeSH
• ionizující záření * MeSH
• mitogenem aktivované proteinkinasy kinas metabolismus   účinky záření   MeSH
• potkani Wistar MeSH
• protein vázající element responzivní pro cyklický AMP metabolismus   účinky záření   MeSH
• protoonkogenní proteiny c-myc metabolismus   účinky záření   MeSH
• radiometrie statistika a číselné údaje   MeSH
• vztah dávky záření a odpovědi MeSH
• western blotting MeSH
• záření gama MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• práce podpořená grantem MeSH

The increasing risk of acute large-scale radiological/nuclear exposures of population underlines the necessity of developing new, rapid and high throughput biodosimetric tools for estimation of received dose and initial triage. We aimed to compare the induction and persistence of different radiation exposure biomarkers in human peripheral blood in vivo. Blood samples of patients with indicated radiotherapy (RT) undergoing partial body irradiation (PBI) were obtained soon before the first treatment and then after 24 h, 48 h, and 5 weeks; i.e. after 1, 2, and 25 fractionated RT procedures. We collected circulating peripheral blood from ten patients with tumor of endometrium (1.8 Gy per fraction) and eight patients with tumor of head and neck (2.0-2.121 Gy per fraction). Incidence of dicentrics and micronuclei was monitored as well as determination of apoptosis and the transcription level of selected radiation-responsive genes. Since mitochondrial DNA (mtDNA) has been reported to be a potential indicator of radiation damage in vitro, we also assessed mtDNA content and deletions by novel multiplex quantitative PCR. Cytogenetic data confirmed linear dose-dependent increase in dicentrics (p < 0.01) and micronuclei (p < 0.001) in peripheral blood mononuclear cells after PBI. Significant up-regulations of five previously identified transcriptional biomarkers of radiation exposure (PHPT1, CCNG1, CDKN1A, GADD45, and SESN1) were also found (p < 0.01). No statistical change in mtDNA deletion levels was detected; however, our data indicate that the total mtDNA content decreased with increasing number of RT fractions. Interestingly, the number of micronuclei appears to correlate with late radiation toxicity (r2 = 0.9025) in endometrial patients suggesting the possibility of predicting the severity of RT-related toxicity by monitoring this parameter. Overall, these data represent, to our best knowledge, the first study providing a multiparametric comparison of radiation biomarkers in human blood in vivo, which have potential for improving biological dosimetry.

• MeSH
• biologické markery krev   MeSH
• celková dávka radioterapie MeSH
• chromozomální aberace MeSH
• genetická transkripce účinky záření   MeSH
• leukocyty patologie   účinky záření   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mikrojádra chromozomálně defektní MeSH
• mitochondriální DNA účinky záření   MeSH
• nádory endometria krev   radioterapie   MeSH
• nádory hlavy a krku krev   radioterapie   MeSH
• radiační expozice * MeSH
• radiometrie metody   MeSH
• radioterapie škodlivé účinky   MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• vztah dávky záření a odpovědi MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• srovnávací studie MeSH

Gastrointestinal form is the second stage of the Acute Radiation Syndrome (ARS) with a threshold dose of 8 Gy. It represents an absolutely lethal clinical-pathological unit, enteritis necro-hemorrhagica (duodenitis, jejunitis, ileitis, respectively) with unknown causal therapy. The purpose of our study has been to evaluate the morphological changes in a model of radiation-induced enteritis in rats and estimate the significance of changes in biodosimetry. Wistar rats were randomly divided into 21 groups, 10 animals per group. Samples of the jejunum were taken 24, 48, 72, and 96 h after the whole-body gamma-irradiation with the doses of 1, 5, 10, 15, and 20 Gy, and routinely stained with hematoxylin and eosin. Five morphometric markers--intercryptal distance, enterocytal height on the top and base of villus, length of basal lamina of 10 enterocytes and enterocytal width--in irradiated rat jejunum were examined. The results were compared with sham-irradiated control group. After lethal doses of irradiation, all morphometric parameters of jejunum significantly changed. With the exception of intercryptal distance, they might be considered as suitable biodosimetric markers under these experimental conditions. Our morphometry results in radiation-induced jejunitis are in accordance with those in other studies. We were the first who quantified morphological post-irradiation changes in animal jejunum. Some of them might be used under experimental conditions. This experimental study is a predecessor of the clinical assessment of a specific marker. Under clinical practice, the sensitive biodosimetric parameter could serve as one of the guidance for evaluation of the absorbed dose in irradiated troops as well as rescue workers. This is in accordance with tasks and Standardization Agreement of the North Atlantic Treaty Organization.

• MeSH
• bazální membrána patologie   účinky záření   MeSH
• časové faktory MeSH
• celotělové ozáření MeSH
• enteritida etiologie   patologie   MeSH
• enterocyty patologie   účinky záření   MeSH
• experimentální radiační poranění patologie   MeSH
• hodnocení rizik MeSH
• jejunum patologie   účinky záření   MeSH
• krysa rodu rattus MeSH
• nemoci jejuna etiologie   patologie   MeSH
• potkani Wistar MeSH
• radiometrie MeSH
• vztah dávky záření a odpovědi MeSH
• záření gama MeSH
• zvířata MeSH
• Check Tag
• krysa rodu rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH