Rationale and recommendations for treatment of radiation injury with cytokines.

Treatment of the hematopoietic syndrome includes replacement with blood products, stem cell transplantation, and the use of hematopoietic cytokines. Cytokines have predictable effects based upon their mechanism of action. Those acting on early hematopoietic stem/progenitor cells have multilineage effects, while those acting upon more differentiated progenitor cells have lineage restricted activity. The selection of cytokines for treatment of acute hematopoietic toxicity in man is largely based upon results of experiments in non-human primates and canines. Since randomized controlled trials are unable to be performed in man after accidental radiation exposure, recommendations for therapy are largely based upon expert opinion. There is general agreement that granulocyte colony-stimulating factor (G-CSF) is an acceptable choice for treatment of individuals receiving a whole-body dose of 3 Gy or more, or 2 Gy or more in the presence of mechanical trauma and/or burns (i.e., combined injury). G-CSF is available in radiation stockpiles that have been developed in the U.S. and by the World Health Organization.