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Caravaca J, Peter R, Yang J, Gunther C, Antonio Camara Serrano J, Nostrand C, Steri V, Seo Y. Comparison and calibration of dose delivered by 137Cs and x-ray irradiators in mice. Phys Med Biol 2022; 67:10.1088/1361-6560/ac9e88. [PMID: 36317316 PMCID: PMC9933773 DOI: 10.1088/1361-6560/ac9e88] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 10/28/2022] [Indexed: 11/07/2022]
Abstract
Objective.The Office of Radiological Security, U.S. Department of Energy's National Nuclear Security Administration, is implementing a radiological risk reduction program which seeks to minimize or eliminate the use of high activity radiological sources, including137Cs, by replacing them with non-radioisotopic technologies, such as x-ray irradiators. The main goal of this paper is to evaluate the equivalence of the dose delivered by gamma- and x-ray irradiators in mice using experimental measurements and Monte Carlo simulations. We also propose a novel biophantom as anin situdose calibration method.Approach.We irradiated mouse carcasses and 3D-printed mouse biophantoms in a137Cs irradiator (Mark I-68) and an x-ray irradiator (X-Rad320) at three voltages (160 kVp, 225 kVp and 320 kVp) and measured the delivered radiation dose. A Geant4-based Monte Carlo model was developed and validated to provide a comprehensive picture of gamma- and x-ray irradiation in mice.Main Results.Our Monte Carlo model predicts a uniform dose delivered in soft-tissue for all the explored irradiation programs and in agreement with the absolute dose measurements. Our Monte Carlo model shows an energy-dependent difference between dose in bone and in soft tissue that decreases as photon energy increases. Dose rate depends on irradiator and photon energy. We observed a deviation of the measured dose from the target value of up to -9% for the Mark I-68, and up to 35% for the X-Rad320. The dose measured in the 3D-printed phantoms are equivalent to that in the carcasses within 6% uncertainty.Significance.Our results suggest that 320 kVp irradiation is a good candidate to substitute137Cs irradiation barring a few caveats. There is a significant difference between measured and targeted doses for x-ray irradiation that suggests a strong need forin situcalibration, which can be achieved with 3D-printed mouse biophantoms. A dose correction is necessary for bone doses, which can be provided by a Monte Carlo calculation. Finally, the biological implications of the differences in dose rates and dose per photon for the different irradiation methods should be carefully assessed for each small-animal irradiation experiment.
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Affiliation(s)
- Javier Caravaca
- Physics Research Laboratory, University of California, San Francisco, United States of America
| | - Robin Peter
- Physics Research Laboratory, University of California, San Francisco, United States of America
- Department of Nuclear Engineering, University of California, Berkeley, United States of America
| | - Jaewon Yang
- Department of Radiology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Chad Gunther
- C&C Irradiator Service, LLC, Washington, DC. United States of America
| | - Juan Antonio Camara Serrano
- Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, United States of America
| | | | - Veronica Steri
- Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco, United States of America
| | - Youngho Seo
- Physics Research Laboratory, University of California, San Francisco, United States of America
- Department of Nuclear Engineering, University of California, Berkeley, United States of America
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Scott BR, Lin Y, Saxton B, Chen W, Potter CA, Belinsky SA. Modeling Cell Survival Fraction and Other Dose-Response Relationships for Immunodeficient C.B-17 SCID Mice Exposed to 320-kV X Rays. Dose Response 2021; 19:15593258211019887. [PMID: 34104124 PMCID: PMC8170291 DOI: 10.1177/15593258211019887] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 04/27/2021] [Accepted: 04/30/2021] [Indexed: 11/16/2022] Open
Abstract
US homeland security concerns related to potential misuse of γ-ray-emitting radiation sources employed in radiobiological research (eg, shielded cesium-137 irradiators) led to recommendations by the National Research Council to conduct studies into possibly replacing γ-ray irradiators used in research involving small rodent and other models with X-ray instruments. A limiting factor is suitability of the X-ray photon energy spectra. The objective of our research was to demonstrate the suitability of the radiation energy spectrum of 320-kV X rays after filtration (HVL = 4 mm Cu) for in-vivo cytotoxicity studies in immunodeficient C.B-17 SCID mice. By using a previously-published Hazard Function (HF) model to characterize dose-response relationships for in vivo bone marrow and spleen cell survival fractions and also to characterize the acute lethality risk (hematopoietic syndrome mode) we demonstrate that the filtered 320-kV X-ray beam appears suitable for such studies. A key finding for C.B-17 SCID mice when compared to results previously obtained for immunocompetent C.B-17 mice is that the immunodeficient mice appear to be more radioresistant, implicating a possible role of the immune system capacity in radiosensitivity of mammals.
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Affiliation(s)
- Bobby R Scott
- Lovelace Biomedical Research Institute, Albuquerque, NM, USA
| | - Yong Lin
- Lovelace Biomedical Research Institute, Albuquerque, NM, USA
| | - Bryanna Saxton
- Lovelace Biomedical Research Institute, Albuquerque, NM, USA
| | - Wenshu Chen
- Lovelace Biomedical Research Institute, Albuquerque, NM, USA
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Wittenborn TR, Fahlquist Hagert C, Ferapontov A, Fonager S, Jensen L, Winther G, Degn SE. Comparison of gamma and x-ray irradiation for myeloablation and establishment of normal and autoimmune syngeneic bone marrow chimeras. PLoS One 2021; 16:e0247501. [PMID: 33730087 PMCID: PMC7968675 DOI: 10.1371/journal.pone.0247501] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 02/09/2021] [Indexed: 02/07/2023] Open
Abstract
Murine bone marrow (BM) chimeras are a versatile and valuable research tool in stem cell and immunology research. Engraftment of donor BM requires myeloablative conditioning of recipients. The most common method used for mice is ionizing radiation, and Cesium-137 gamma irradiators have been preferred. However, radioactive sources are being out-phased worldwide due to safety concerns, and are most commonly replaced by X-ray sources, creating a need to compare these sources regarding efficiency and potential side effects. Prior research has proven both methods capable of efficiently ablating BM cells and splenocytes in mice, but with moderate differences in resultant donor chimerism across tissues. Here, we compared Cesium-137 to 350 keV X-ray irradiation with respect to immune reconstitution, assaying complete, syngeneic BM chimeras and a mixed chimera model of autoimmune disease. Based on dose titration, we find that both gamma and X-ray irradiation can facilitate a near-complete donor chimerism. Mice subjected to 13 Gy Cesium-137 irradiation and reconstituted with syngeneic donor marrow were viable and displayed high donor chimerism, whereas X-ray irradiated mice all succumbed at 13 Gy. However, a similar degree of chimerism as that obtained following 13 Gy gamma irradiation could be achieved by 11 Gy X-ray irradiation, about 85% relative to the gamma dose. In the mixed chimera model of autoimmune disease, we found that a similar autoimmune phenotype could be achieved irrespective of irradiation source used. It is thus possible to compare data generated, regardless of the irradiation source, but every setup and application likely needs individual optimization.
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Affiliation(s)
- Thomas Rea Wittenborn
- The Laboratory for Lymphocyte Biology, Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Cecilia Fahlquist Hagert
- The Laboratory for Lymphocyte Biology, Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Alexey Ferapontov
- The Laboratory for Lymphocyte Biology, Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Sofie Fonager
- The Laboratory for Lymphocyte Biology, Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Lisbeth Jensen
- The Laboratory for Lymphocyte Biology, Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Gudrun Winther
- The Laboratory for Lymphocyte Biology, Department of Biomedicine, Aarhus University, Aarhus, Denmark
| | - Søren Egedal Degn
- The Laboratory for Lymphocyte Biology, Department of Biomedicine, Aarhus University, Aarhus, Denmark
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4
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Andersen AHF, Nielsen SSF, Olesen R, Harslund JLF, Søgaard OS, Østergaard L, Denton PW, Tolstrup M. Comparable human reconstitution following Cesium-137 versus X-ray irradiation preconditioning in immunodeficient NOG mice. PLoS One 2020; 15:e0241375. [PMID: 33119684 PMCID: PMC7595384 DOI: 10.1371/journal.pone.0241375] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 10/14/2020] [Indexed: 12/26/2022] Open
Abstract
Humanized mouse models are used extensively in research involving human pathogens and diseases. However, most of these models require preconditioning. Radio-active sources have been used routinely for this purpose but safety issues have motivated researchers to transition to chemical or X-ray based preconditioning. In this study, we directly compare 350 kV X-ray and Cs-137 low-dose precondition of NOG mice before human stem cell transplantation. Based on flow cytometry data, we found that engraftment of human cells into the mouse bone marrow was similar between radiation sources. Likewise, human engraftment in the peripheral blood was comparable between Cs-137 and three different X-ray doses with equal chimerization kinetics. In primary lymphoid organs such as the thymus and lymph nodes, and spleen, liver and lung, human-to-mouse chimerization was also comparable between irradiation sources. Development of different CD4 and CD8 T cells as well as these cells’ maturation stages, i.e. from naïve to effector and memory subsets were generally analogous. Based on our results, we conclude that there are no discernable differences between the two sources in the low-dose spectrum investigated. However, while we encourage the transition to X-ray-based sources, we recommend all research groups to consider technical specifications and dose-finding studies.
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Affiliation(s)
- Anna Halling Folkmar Andersen
- Department of Infectious Diseases, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
- * E-mail:
| | - Stine Sofie Frank Nielsen
- Department of Infectious Diseases, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Rikke Olesen
- Department of Infectious Diseases, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | | | | | - Lars Østergaard
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Paul W. Denton
- Department of Biology, University of Nebraska at Omaha, Omaha, Nebraska, United States of America
| | - Martin Tolstrup
- Department of Infectious Diseases, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
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Gott KM, Potter CA, Doyle-Eisele M, Lin Y, Wilder J, Scott BR. A Comparison of Cs-137 γ Rays and 320-kV X-Rays in a Mouse Bone Marrow Transplantation Model. Dose Response 2020; 18:1559325820916572. [PMID: 32284702 PMCID: PMC7139189 DOI: 10.1177/1559325820916572] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 02/11/2020] [Accepted: 02/18/2020] [Indexed: 01/14/2023] Open
Abstract
US homeland security concerns regarding the potential misuse of some radiation
sources used in radiobiological research, for example, cesium-137
(137Cs), have resulted in recommendations by the National
Research Council to conduct studies into replacing these sources with suitable
X-ray instruments. The objective of this research is to compare the
effectiveness of an X-RAD 320 irradiator (PXINC 2010) with a 137Cs
irradiator (Gammacell-1000 Unit) using an established bone marrow chimeric
model. Using measured radiation doses for each instrument, we characterized the
dose–response relationships for bone marrow and splenocyte ablation, using a
cytotoxicity-hazard model. Our results show that the X-RAD 320 photon energy
spectrum was suitable for ablating bone marrow at the 3 exposure levels used,
similar to that of 137Cs photons. However, the 320-kV X-rays were not
as effective as the much higher energy γ rays at depleting mouse splenocytes.
Furthermore, the 3 X-ray levels used were less effective than the higher energy
γ rays in allowing the successful engraftment of donor bone marrow, potentially
as a result of the incomplete depletion of the spleen cells. More defined
studies are warranted for determining whether bone marrow transplantation in
mice can be successfully achieved using 320-kV X-rays. A higher X-ray dose then
used is likely needed for transplantation success.
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Affiliation(s)
| | | | | | - Yong Lin
- Lovelace Respiratory Research Institute, Albuquerque, NM, USA
| | - Julie Wilder
- Sandia National Laboratories, Albuquerque, NM, USA
| | - Bobby R Scott
- Lovelace Respiratory Research Institute, Albuquerque, NM, USA
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Preclinical murine platform to evaluate therapeutic countermeasures against radiation-induced gastrointestinal syndrome. Proc Natl Acad Sci U S A 2019; 116:20672-20678. [PMID: 31551264 PMCID: PMC6789742 DOI: 10.1073/pnas.1906611116] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Currently, there are no therapies available to mitigate intestinal damage after radiation injury. Efforts to study and design new therapies are hampered by a lack of models that can be readily adopted to study therapeutic targets. Here we describe a preclinical platform to evaluate therapeutic countermeasures against intestinal radiation injury in vivo in a mouse model that permits inducible and reversible gene suppression following radiation exposure. We demonstrate that transient intestinal Apc suppression stimulates intestinal regeneration and mitigates lethality after radiation intestinal injury, thus validating pulsed Wnt pathway agonism as a therapeutic strategy. This platform can be readily adopted to study theoretically any gene of interest associated with the biology and treatment of intestinal radiation injury. Radiation-induced gastrointestinal syndrome (RIGS) is a limiting factor for therapeutic abdominopelvic radiation and is predicted to be a major source of morbidity in the event of a nuclear accident or radiological terrorism. In this study, we developed an in vivo mouse-modeling platform that enables spatial and temporal manipulation of potential RIGS targets in mice following whole-abdomen irradiation without the confounding effects of concomitant hematopoietic syndrome that occur following whole-body irradiation. We then tested the utility of this platform to explore the effects of transient Wnt pathway activation on intestinal regeneration and animal recovery following induction of RIGS. Our results demonstrate that intestinal epithelial suppression of adenomatous polyposis coli (Apc) mitigates RIGS lethality in vivo after lethal ionizing radiation injury-induced intestinal epithelial damage. These results highlight the potential of short-term Wnt agonism as a therapeutic target and establish a platform to evaluate other strategies to stimulate intestinal regeneration after ionizing radiation damage.
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Cruz-Garcia L, O’Brien G, Donovan E, Gothard L, Boyle S, Laval A, Testard I, Ponge L, Woźniak G, Miszczyk L, Candéias SM, Ainsbury E, Widlak P, Somaiah N, Badie C. Influence of Confounding Factors on Radiation Dose Estimation Using In Vivo Validated Transcriptional Biomarkers. HEALTH PHYSICS 2018; 115:90-101. [PMID: 29787434 PMCID: PMC5967635 DOI: 10.1097/hp.0000000000000844] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
For triage purposes following a nuclear accident, blood-based gene expression biomarkers can provide rapid dose estimates for a large number of individuals. Ionizing-radiation-responsive genes are regulated through the DNA damage-response pathway, which includes activation of multiple transcription factors. Modulators of this pathway could potentially affect the response of these biomarkers and consequently compromise accurate dose estimation calculations. In the present study, four potential confounding factors were selected: cancer condition, sex, simulated bacterial infection (lipopolysaccharide), and curcumin, an anti-inflammatory/antioxidant agent. Their potential influence on the transcriptional response to radiation of the genes CCNG1 and PHPT1, two biomarkers of radiation exposure ex vivo, was assessed. First, both CCNG1 and PHPT1 were detected in vivo in blood samples from radiotherapy patients and as such were validated as biomarkers of exposure. Importantly, their basal expression level was slightly but significantly affected in vivo by patients' cancer condition. Moreover, lipopolysaccharide stimulation of blood irradiated ex vivo led to a significant modification of CCNG1 and PHPT1 transcriptional response in a dose- and time-dependent manner with opposite regulatory effects. Curcumin also affected CCNG1 and PHPT1 transcriptional response counteracting some of the radiation induction. No differences were observed based on sex. Dose estimations calculated using linear regression were affected by lipopolysaccharide and curcumin. In conclusion, several confounding factors tested in this study can indeed modulate the transcriptional response of CCNG1 and PHPT1 and consequently can affect radiation exposure dose estimations but not to a level which should prevent the biomarkers' use for triage purposes.
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Affiliation(s)
- Lourdes Cruz-Garcia
- Radiation Effects Department, Centre for Radiation, Chemical & Environmental Hazards Public Health England Chilton, Didcot, Oxfordshire OX11 ORQ United Kingdom
| | - Grainne O’Brien
- Radiation Effects Department, Centre for Radiation, Chemical & Environmental Hazards Public Health England Chilton, Didcot, Oxfordshire OX11 ORQ United Kingdom
| | - Ellen Donovan
- Centre for Vision Speech and Signal Processing, University of Surrey, Guildford, GU2 7TE, UK
| | - Lone Gothard
- Institute for Cancer Research/Royal Marsden NHS Foundation Trust, Downs Road, Sutton SM2 5PT, UK
| | - Sue Boyle
- Institute for Cancer Research/Royal Marsden NHS Foundation Trust, Downs Road, Sutton SM2 5PT, UK
| | - Antoine Laval
- CEA, DRF, BIG-LCBM, F-38000 Grenoble, France. CNRS, LCBM, UMR 5249, F-38000 Grenoble, France.Univ. Grenoble Alpes, BIG-LCBM, F-38000 Grenoble, France
| | - Isabelle Testard
- CEA, DRF, BIG-LCBM, F-38000 Grenoble, France. CNRS, LCBM, UMR 5249, F-38000 Grenoble, France.Univ. Grenoble Alpes, BIG-LCBM, F-38000 Grenoble, France
| | - Lucyna Ponge
- Maria Sklodowska-Curie Institute – Oncology Center, Gliwice Branch, 44-101 Gliwice, Poland
| | - Grzegorz Woźniak
- Maria Sklodowska-Curie Institute – Oncology Center, Gliwice Branch, 44-101 Gliwice, Poland
| | - Leszek Miszczyk
- Maria Sklodowska-Curie Institute – Oncology Center, Gliwice Branch, 44-101 Gliwice, Poland
| | - Serge M. Candéias
- CEA, DRF, BIG-LCBM, F-38000 Grenoble, France. CNRS, LCBM, UMR 5249, F-38000 Grenoble, France.Univ. Grenoble Alpes, BIG-LCBM, F-38000 Grenoble, France
| | - Elizabeth Ainsbury
- Radiation Effects Department, Centre for Radiation, Chemical & Environmental Hazards Public Health England Chilton, Didcot, Oxfordshire OX11 ORQ United Kingdom
| | - Piotr Widlak
- Maria Sklodowska-Curie Institute – Oncology Center, Gliwice Branch, 44-101 Gliwice, Poland
| | - Navita Somaiah
- Institute for Cancer Research/Royal Marsden NHS Foundation Trust, Downs Road, Sutton SM2 5PT, UK
| | - Christophe Badie
- Radiation Effects Department, Centre for Radiation, Chemical & Environmental Hazards Public Health England Chilton, Didcot, Oxfordshire OX11 ORQ United Kingdom
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Acceleration of atherogenesis in ApoE-/- mice exposed to acute or low-dose-rate ionizing radiation. Oncotarget 2016; 6:31263-71. [PMID: 26359350 PMCID: PMC4741603 DOI: 10.18632/oncotarget.5075] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Accepted: 08/10/2015] [Indexed: 11/25/2022] Open
Abstract
There is epidemiological evidence for increased non-cancer mortality, primarily due to circulatory diseases after radiation exposure above 0.5 Sv. We evaluated the effects of chronic low-dose rate versus acute exposures in a murine model of spontaneous atherogenesis. Female ApoE-/- mice (60 days) were chronically irradiated for 300 days with gamma rays at two different dose rates (1 mGy/day; 20 mGy/day), with total accumulated doses of 0.3 or 6 Gy. For comparison, age-matched ApoE-/- females were acutely exposed to the same doses and sacrificed 300 days post-irradiation. Mice acutely exposed to 0.3 or 6 Gy showed increased atherogenesis compared to age-matched controls, and this effect was persistent. When the same doses were delivered at low dose rate over 300 days, we again observed a significant impact on global development of atherosclerosis, although at 0.3 Gy effects were limited to the descending thoracic aorta. Our data suggest that a moderate dose of 0.3 Gy can have persistent detrimental effects on the cardiovascular system, and that a high dose of 6 Gy poses high risks at both high and low dose rates. Our results were clearly nonlinear with dose, suggesting that lower doses may be more damaging than predicted by a linear dose response.
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Scott BR, Potter CA. Stochastic Threshold Exponential (TE) Model for Hematopoietic Tissue Reconstitution Deficit after Radiation Damage. Dose Response 2014; 12:415-28. [PMID: 25249834 DOI: 10.2203/dose-response.13-041.scott] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Whole-body exposure to large radiation doses can cause severe loss of hematopoietic tissue cells and threaten life if the lost cells are not replaced in a timely manner through natural repopulation (a homeostatic mechanism). Repopulation to the baseline level N 0 is called reconstitution and a reconstitution deficit (repopulation shortfall) can occur in a dose-related and organ-specific manner. Scott et al. (2013) previously introduced a deterministic version of a threshold exponential (TE) model of tissue-reconstitution deficit at a given follow-up time that was applied to bone marrow and spleen cellularity (number of constituent cells) data obtained 6 weeks after whole-body gamma-ray exposure of female C.B-17 mice. In this paper a more realistic, stochastic version of the TE model is provided that allows radiation response to vary between different individuals. The Stochastic TE model is applied to post gamma-ray-exposure cellularity data previously reported and also to more limited X-ray cellularity data for whole-body irradiated female C.B-17 mice. Results indicate that the population average threshold for a tissue reconstitution deficit appears to be similar for bone marrow and spleen and for 320-kV-spectrum X-rays and Cs-137 gamma rays. This means that 320-kV spectrum X-rays could successfully be used in conducting such studies.
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Affiliation(s)
- B R Scott
- Lovelace Respiratory Research Institute, Albuquerque, NM
| | - C A Potter
- Sandia National Laboratories, Organization 00545, Albuquerque, NM
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