Inflammation and Immunity in Radiation Damage to the Gut Mucosa

Laboratory of Radiopathology and Experimental Therapeutics, Institute for Radiological Protection and Nuclear Safety, 31 Avenue de la Division Leclerc, 92262 Fontenay-aux-Roses, France.
BioMed research international 03/2013; 2013(22):123241. DOI: 10.1155/2013/123241
Source: PubMed

ABSTRACT Erythema was observed on the skin of the first patients treated with radiation therapy. It is in particular to reduce this erythema, one feature of tissue inflammation, that prescribed dose to the tumor site started to be fractionated. It is now well known that radiation exposure of normal tissues generates a sustained and apparently uncontrolled inflammatory process. Radiation-induced inflammation is always observed, often described, sometimes partly explained, but still today far from being completely understood. The thing with the gut and especially the gut mucosa is that it is at the frontier between the external milieu and the organism, is in contact with a plethora of commensal and foreign antigens, possesses a dense-associated lymphoid tissue, and is particularly radiation sensitive because of a high mucosal turnover rate. All these characteristics make the gut mucosa a strong responsive organ in terms of radiation-induced immunoinflammation. This paper will focus on what has been observed in the normal gut and what remains to be done concerning the immunoinflammatory response following localized radiation exposure.

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    • "Radiation-induced acute inflammatory responses have been shown to activate multiple pro-inflammatory cytokines and inhibit anti-inflammatory cytokines; thus, cytokines are often used to modulate the effects of IR [1]. The excessive gastrointestinal (GI) inflammatory response that occurs following radiation is considered one of the drivers of multiple organ failure induced by IR [2], [3]. For example, pulmonary injury may be an abscopal effect of GI irradiation injury [4]. "
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