Acute radiation syndrome (ARS) – treatment of the reduced host defense

Lars Heslet1, Christiane Bay2, Steen Nepper-Christensen31Serendex ApS, Gentofte; 2University of Copenhagen, Medical Faculty, Copenhagen; 3Department of Head and Neck Surgery, Otorhinolaryngology, Køge University Hospital, Køge, DenmarkBackground: The current radiation t...

Full description

Bibliographic Details
Main Authors: Heslet L, Bay C, Nepper-Christensen S
Format: Article
Language:English
Published: Dove Medical Press 2012-01-01
Series:International Journal of General Medicine
Online Access:http://www.dovepress.com/acute-radiation-syndrome-ars-ndash-treatment-of-the-reduced-host-defen-a9152
_version_ 1811215167302664192
author Heslet L
Bay C
Nepper-Christensen S
author_facet Heslet L
Bay C
Nepper-Christensen S
author_sort Heslet L
collection DOAJ
description Lars Heslet1, Christiane Bay2, Steen Nepper-Christensen31Serendex ApS, Gentofte; 2University of Copenhagen, Medical Faculty, Copenhagen; 3Department of Head and Neck Surgery, Otorhinolaryngology, Køge University Hospital, Køge, DenmarkBackground: The current radiation threat from the Fukushima power plant accident has prompted rethinking of the contingency plan for prophylaxis and treatment of the acute radiation syndrome (ARS). The well-documented effect of the growth factors (granulocyte colony-stimulating factor [G-CSF] and granulocyte-macrophage colony-stimulating factor [GM-CSF]) in acute radiation injury has become standard treatment for ARS in the United States, based on the fact that growth factors increase number and functions of both macrophages and granulocytes.Methods: Review of the current literature.Results: The lungs have their own host defense system, based on alveolar macrophages. After radiation exposure to the lungs, resting macrophages can no longer be transformed, not even during systemic administration of growth factors because G-CSF/GM-CSF does not penetrate the alveoli. Under normal circumstances, locally-produced GM-CSF receptors transform resting macrophages into fully immunocompetent dendritic cells in the sealed-off pulmonary compartment. However, GM-CSF is not expressed in radiation injured tissue due to defervescence of the macrophages. In order to maintain the macrophage’s important role in host defense after radiation exposure, it is hypothesized that it is necessary to administer the drug exogenously in order to uphold the barrier against exogenous and endogenous infections and possibly prevent the potentially lethal systemic infection, which is the main cause of death in ARS.Recommendation: Preemptive treatment should be initiated after suspected exposure of a radiation dose of at least ~2 Gy by prompt dosing of 250–400 µg GM-CSF/m2 or 5 µg/kg G-CSF administered systemically and concomitant inhalation of GM-CSF ~ 300 mcg per day for at least 14–21 days.Conclusion: The present United States standard for prevention and treatment of ARS standard intervention should consequently be modified into the combined systemic administration of growth factors and inhaled GM-CSF to ensure the sustained systemic and pulmonary host defense and thus prevent pulmonary dysfunction.Keywords: inhaled and systemically administered GM-CSF, ARS, host defense, orchestration of pulmonary host response
first_indexed 2024-04-12T06:17:21Z
format Article
id doaj.art-a3557b432cd5452f8f5a4764bda5dbf7
institution Directory Open Access Journal
issn 1178-7074
language English
last_indexed 2024-04-12T06:17:21Z
publishDate 2012-01-01
publisher Dove Medical Press
record_format Article
series International Journal of General Medicine
spelling doaj.art-a3557b432cd5452f8f5a4764bda5dbf72022-12-22T03:44:26ZengDove Medical PressInternational Journal of General Medicine1178-70742012-01-012012default105115Acute radiation syndrome (ARS) – treatment of the reduced host defenseHeslet LBay CNepper-Christensen SLars Heslet1, Christiane Bay2, Steen Nepper-Christensen31Serendex ApS, Gentofte; 2University of Copenhagen, Medical Faculty, Copenhagen; 3Department of Head and Neck Surgery, Otorhinolaryngology, Køge University Hospital, Køge, DenmarkBackground: The current radiation threat from the Fukushima power plant accident has prompted rethinking of the contingency plan for prophylaxis and treatment of the acute radiation syndrome (ARS). The well-documented effect of the growth factors (granulocyte colony-stimulating factor [G-CSF] and granulocyte-macrophage colony-stimulating factor [GM-CSF]) in acute radiation injury has become standard treatment for ARS in the United States, based on the fact that growth factors increase number and functions of both macrophages and granulocytes.Methods: Review of the current literature.Results: The lungs have their own host defense system, based on alveolar macrophages. After radiation exposure to the lungs, resting macrophages can no longer be transformed, not even during systemic administration of growth factors because G-CSF/GM-CSF does not penetrate the alveoli. Under normal circumstances, locally-produced GM-CSF receptors transform resting macrophages into fully immunocompetent dendritic cells in the sealed-off pulmonary compartment. However, GM-CSF is not expressed in radiation injured tissue due to defervescence of the macrophages. In order to maintain the macrophage’s important role in host defense after radiation exposure, it is hypothesized that it is necessary to administer the drug exogenously in order to uphold the barrier against exogenous and endogenous infections and possibly prevent the potentially lethal systemic infection, which is the main cause of death in ARS.Recommendation: Preemptive treatment should be initiated after suspected exposure of a radiation dose of at least ~2 Gy by prompt dosing of 250–400 µg GM-CSF/m2 or 5 µg/kg G-CSF administered systemically and concomitant inhalation of GM-CSF ~ 300 mcg per day for at least 14–21 days.Conclusion: The present United States standard for prevention and treatment of ARS standard intervention should consequently be modified into the combined systemic administration of growth factors and inhaled GM-CSF to ensure the sustained systemic and pulmonary host defense and thus prevent pulmonary dysfunction.Keywords: inhaled and systemically administered GM-CSF, ARS, host defense, orchestration of pulmonary host responsehttp://www.dovepress.com/acute-radiation-syndrome-ars-ndash-treatment-of-the-reduced-host-defen-a9152
spellingShingle Heslet L
Bay C
Nepper-Christensen S
Acute radiation syndrome (ARS) – treatment of the reduced host defense
International Journal of General Medicine
title Acute radiation syndrome (ARS) – treatment of the reduced host defense
title_full Acute radiation syndrome (ARS) – treatment of the reduced host defense
title_fullStr Acute radiation syndrome (ARS) – treatment of the reduced host defense
title_full_unstemmed Acute radiation syndrome (ARS) – treatment of the reduced host defense
title_short Acute radiation syndrome (ARS) – treatment of the reduced host defense
title_sort acute radiation syndrome ars amp ndash treatment of the reduced host defense
url http://www.dovepress.com/acute-radiation-syndrome-ars-ndash-treatment-of-the-reduced-host-defen-a9152
work_keys_str_mv AT hesletl acuteradiationsyndromearsampndashtreatmentofthereducedhostdefense
AT bayc acuteradiationsyndromearsampndashtreatmentofthereducedhostdefense
AT nepperchristensens acuteradiationsyndromearsampndashtreatmentofthereducedhostdefense