Determination of the changes induced by ionizing radiation in the cell population and cytokine profile of peripheral blood and lungs

The effect of whole-body irradiation of the mouse strain C57BL/6 with ionizing radiation at a 8 Gy dose was investigated. The measurements were made in 4, 8 and 24 hours and 7, 21 and 30 days after irradiation and compared to those obtained for a non-irradiated control group. Flow cytometry was used to determine the major cell populations (lymphocytes, monocytes and granulocytes) in peripheral blood and in the lungs, lymphocyte subpopulations (T, B and NK cells) in blood, and the subsets of CD4+ T - lymphocytes (Th1, Th2 and Th17). The absolute leukocyte numbers were also measured. The results demonstrate time-dependent body response to the gamma irradiation consisting in changes in the relative leukocyte/ lymphocyte population proportions in both tissue types (peripheral blood and lungs). Lymphocytes, particularly the B-lymphocyte population, were most radiosensitive whereas macrophages in the lung tissue were most radioresistant. The cytokine results exhibited significant changes in the periodically measured concentrations of MCP-1 (peripheral blood and lungs), IL-6 (peripheral blood) and TNF (lung). (orig.)