Intercellular communications in experimental radio-pathology: the radio-induced inflammatory syndrome

The monolithic image of radiation pathology, the physiopathological mechanisms of which are limited to the conventional concept of specific ' target cell ' with mitotic and apoptotic cell death, is changing owing to our increasing knowledge about intercellular communications. The cellular radiation biology is currently enriched by the ' humoral ' radiation biology with its concept of ' target network ' including cells and intercellular messengers. The radiation-induced disorders observed in these networks take shape in the inflammatory reaction, which is largely involved, in the physiopathological development of the acute radiation syndrome. The concepts of a perpetual cascade of cytokines, leading to radiation-induced late effects with no biological latent period, are especially illustrated by the radiation-induced pneumonitis and pulmonary fibrosis. (authors)