Alteration of cytokine profiles in mice exposed to chronic low-dose ionizing radiation.
While a high-dose of ionizing radiation is generally harmful and causes damage to living organisms, a low-dose of radiation has been shown to be beneficial in a variety of animal models. To understand the basis for the effect of low-dose radiation in vivo, we examined the cellular and immunological changes evoked in mice exposed to low-dose radiation at very low (0.7mGy/h) and low (3.95mGy/h) dose rate for the total dose of 0.2 and 2Gy, respectively. Mice exposed to low-dose radiation, either at very low- or low-dose rate, demonstrated normal range of body weight and complete blood counts. Likewise, the number and percentage of peripheral lymphocyte populations, CD4(+) T, CD8(+) T, B, or NK cells, stayed unchanged following irradiation. Nonetheless, the sera from these mice exhibited elevated levels of IL-3, IL-4, leptin, MCP-1, MCP-5, MIP-1alpha, thrombopoietin, and VEGF along with slight reduction of IL-12p70, IL-13, IL-17, and IFN-gamma. This pattern of cytokine release suggests the stimulation of innate immunity facilitating myeloid differentiation and activation while suppressing pro-inflammatory responses and promoting differentiation of naïve T cells into T-helper 2, not T-helper 1, types. Collectively, our data highlight the subtle changes of cytokine milieu by chronic low-dose gamma-radiation, which may be associated with the functional benefits observed in various experimental models.
Shin
Suk Chul
SC
Radiation Health Research Institute, Korea Hydro & Nuclear Power Co., Ltd., 388-1, Ssangmun-dong, Dobong-gu, Seoul 132-703, Republic of Korea.
Lee
Kyung-Mi
KM
Kang
Yu Mi
YM
Kim
Kwanghee
K
Kim
Cha Soon
CS
Yang
Kwang Hee
KH
Jin
Young-Woo
YW
Kim
Chong Soon
CS
Kim
Hee Sun
HS
D000818:Animals; D001773:Blood Cells / Q000276:immunology / Q000528:radiation effects; D001835:Body Weight / Q000528:radiation effects; D016207:Cytokines / Q000378:metabolism*; D004307:Dose-Response Relationship, Radiation; D005260:Female; D005720:Gamma Rays; D007109:Immunity / Q000528:radiation effects*; D008214:Lymphocytes / Q000276:immunology / Q000528:radiation effects; D051379:Mice; D008810:Mice, Inbred C57BL
D016207:Cytokines