Journal Article The differential role of human macrophage in triggering secondary bystander effects after either gamma-ray or carbon beam irradiation.

Dong, Chen  ,  He, Mingyuan  ,  Tu, Wenzhi  ,  Konishi, Teruaki  ,  Liu, Weili  ,  Xie, Yuexia  ,  Dang, Bingrong  ,  Li, Wenjian  ,  Uchihori, Yukio  ,  K. Hei, Tom  ,  Shao, Chunlin

363 ( 1 )  , pp.92 - 100 , 2015-04 , Elsevier Inc.
The abscopal effect could be an underlying factor in evaluating prognosis of radiotherapy. This study established an in vitro system to examine whether tumor-generated bystander signals could be transmitted by macrophages to further trigger secondary cellular responses after different irradiations, where human lung cancer NCI-H446 cells were irradiated with either γ-rays or carbon ions and co-cultured with human macrophage U937 cells, then these U937 cells were used as a bystander signal transmitter and co-cultured with human bronchial epithelial cells BEAS-2B. Results showed that U937 cells were only activated by γ-irradiated NCI-H446 cells so that the secondary injuries in BEAS-2B cells under carbon ion irradiation were weaker than γ-rays. Both TNF-α and IL-1α were involved in γ-irradiation induced secondary bystander effect but only TNF-α contributed to the carbon ion induced response. Further assay disclosed that IL-1α but not TNF-α was largely responsible for the activation of macrophages and the formation of micronucleus in BEAS-2B cells. These data suggest that macrophages could transfer secondary bystander signals and play a key role in the secondary bystander effect of photon irradiation while carbon ion irradiation has conspicuous advantage due to its reduced secondary injury.

Number of accesses :  

Other information