Department of Radiation Therapy and Oncology, University of Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany.
Curr Med Chem. 2012;19(12):1741-50. doi: 10.2174/092986712800099866.
During the last decade, a multitude of experimental evidence has accumulated showing that low-dose radiation therapy (single dose 0.5-1 Gy) functionally modulates a variety of inflammatory processes and cellular compounds including endothelial (EC), mononuclear (PBMC) and polymorphonuclear (PMN) cells, respectively. These modulations comprise a hampered leukocyte adhesion to EC, induction of apoptosis, a reduced activity of the inducible nitric oxide synthase, and a lowered oxidative burst in macrophages. Moreover, irradiation with a single dose between 0.5-0.7 Gy has been shown to induce the expression of X-chromosome linked inhibitor of apoptosis and transforming growth factor beta 1, to reduce the expression of E-selectin and L-selectin from EC and PBMC, and to hamper secretion of Interleukin-1, or chemokine CCL20 from macrophages and PMN. Notably, a common feature of most of these responses is that they display discontinuous or biphasic dose dependencies, shared with "non-targeted" effects of low-dose irradiation exposure like the bystander response and hyper-radiosensitivity. Thus, the purpose of the present review is to discuss recent developments in the understanding of low-dose irradiation immune modulating properties with special emphasis on discontinuous dose response relationships.
在过去的十年中，大量的实验证据积累表明，低剂量辐射疗法（单次剂量 0.5-1 Gy）可以分别调节多种炎症过程和细胞化合物，包括内皮细胞（EC）、单核细胞（PBMC）和多形核细胞（PMN）。这些调节包括白细胞与 EC 的黏附受阻、诱导细胞凋亡、诱导型一氧化氮合酶活性降低以及巨噬细胞氧化爆发降低。此外，单次照射 0.5-0.7 Gy 的剂量已被证明可以诱导凋亡抑制因子和转化生长因子β 1 的表达，降低 EC 和 PBMC 中 E-选择素和 L-选择素的表达，并抑制白细胞介素-1 或趋化因子 CCL20 从巨噬细胞和 PMN 的分泌。值得注意的是，这些反应的一个共同特征是，它们表现出不连续或双相剂量依赖性，与低剂量照射的“非靶向”效应（如旁观者效应和超放射敏感性）共享。因此，本综述的目的是讨论对低剂量辐射免疫调节特性的理解的最新进展，特别强调不连续剂量反应关系。
