Ina Yasuhiro, Sakai Kazuo
LDRC (Low Dose Radiation Research Center), CRIEPI (Central Research Institute of Electric Power Industry), Komae, Tokyo, Japan.
Int J Radiat Biol. 2005 Oct;81(10):721-9. doi: 10.1080/09553000500519808.
To analyse the effects of chronic whole body low-dose-rate irradiation on the immune system in various wild-type mouse strains in comparison with the effects from acute high-dose-rate irradiation.
Wild-type mouse strains (C57BL/6, BALB/c, C3H/He, DBA/1, DBA/2 and CBA) were observed after chronic low-dose-rate gamma irradiation at 1.2 mGy hour(-1) by intensive analysis of immune cell populations and their various surface molecules, together with antibody-producing activity both with and without immunization by sheep red blood cells (SRBC). The cell surface functional molecules [cluster of differentiation (CD) 3, CD4, CD8, CD19, CD45R/B220, intercellular adhesion molecule (ICAM)-1, Fas, natural killer (NK)-1.1, chemokine [C-X-C motif] receptor 4 (CXCR4) and chemokine [C-C motif] receptor 5 (CCR5)] and activation molecules [thymocyte-activating molecule (THAM), CD28, CD40, CD44H, CD70, B7-1, B7-2, OX-40 antigen, cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), CD30 ligand and CD40 ligand] were studied in the bone marrow, thymus, spleen, lymph nodes and peripheral blood by flow cytometry.
By chronic low-dose-rate irradiation alone, CD4+ T cells and CD8 molecule expression increased significantly by a maximum of 30%, while CD40+ B cells decreased significantly. Increases of CD4+ T cells, CD40+ B cells and anti-SRBC antibody-producing cells by immunization were significantly enhanced by continuous low-dose-rate irradiation at 1.2 mGy hour(-1). CD3- CD4+ T cells, representative of abnormal immune cells, were absent in the chronically low-dose-rate-irradiated mice, while a dose-dependent increase of these cells was found in acutely high-dose-rate-irradiated mice given the same total doses.
Chronic low-dose-rate radiation activated the immune system of the whole body.
分析慢性全身低剂量率照射对各种野生型小鼠品系免疫系统的影响，并与急性高剂量率照射的影响进行比较。
对野生型小鼠品系（C57BL/6、BALB/c、C3H/He、DBA/1、DBA/2和CBA）进行1.2 mGy/小时的慢性低剂量率γ射线照射后，通过对免疫细胞群体及其各种表面分子进行深入分析，以及对有无绵羊红细胞（SRBC）免疫的抗体产生活性进行分析。通过流式细胞术研究骨髓、胸腺、脾脏、淋巴结和外周血中的细胞表面功能分子[分化簇（CD）3、CD4、CD8、CD19、CD45R/B220、细胞间黏附分子（ICAM）-1、Fas、自然杀伤（NK）-1.1、趋化因子[C-X-C基序]受体4（CXCR4）和趋化因子[C-C基序]受体5（CCR5）]以及激活分子[胸腺细胞激活分子（THAM）、CD28、CD40、CD44H、CD70、B7-1、B7-2、OX-40抗原、细胞毒性T淋巴细胞相关蛋白4（CTLA-4）、CD30配体和CD40配体]。
仅通过慢性低剂量率照射，CD4+ T细胞和CD8分子表达显著增加，最高可达30%；而CD40+ B细胞显著减少。1.2 mGy/小时的持续低剂量率照射显著增强了免疫后CD4+ T细胞、CD40+ B细胞和抗SRBC抗体产生细胞的增加。慢性低剂量率照射的小鼠中不存在代表异常免疫细胞的CD3-CD4+ T细胞，而在给予相同总剂量的急性高剂量率照射小鼠中发现这些细胞呈剂量依赖性增加。
慢性低剂量率辐射激活了全身免疫系统。
