title: Dose response of micronuclei induced by combination radiation of α-particles and γ-rays in human lymphoblast cells.
abstract: Combination radiation is a real situation of both nuclear accident exposure and space radiation environment, but its biological dosimetry is still not established. This study investigated the dose-response of micronuclei (MN) induction in lymphocyte by irradiating HMy2.CIR lymphoblast cells with α-particles, γ-rays, and their combinations. Results showed that the dose-response of MN induced by γ-rays was well-fitted with the linear-quadratic model. But for α-particle irradiation, the MN induction had a biphasic phenomenon containing a low dose hypersensitivity characteristic and its dose response could be well-stimulated with a state vector model where radiation-induced bystander effect (RIBE) was involved. For the combination exposure, the dose response of MN was similar to that of α-irradiation. However, the yield of MN was closely related to the sequence of irradiations. When the cells were irradiated with α-particles at first and then γ-rays, a synergistic effect of MN induction was observed. But when the cells were irradiated with γ-rays followed by α-particles, an antagonistic effect of MN was observed in the low dose range although this combination radiation also yielded a synergistic effect at high doses. When the interval between two irradiations was extended to 4h, a cross-adaptive response against the other irradiation was induced by a low dose of γ-rays but not α-particles.
authors: Institute of Radiation Medicine, Fudan University, Shanghai, China.
authors: Ruiping
authors: R
authors: Ren
authors: Mingyuan
authors: M
authors: He
authors: Chen
authors: C
authors: Dong
authors: Yuexia
authors: Y
authors: Xie
authors: Shuang
authors: S
authors: Ye
authors: Dexiao
authors: D
authors: Yuan
authors: Chunlin
authors: C
authors: Shao
mesh_terms: D000222:Adaptation, Physiological / Q000528:radiation effects*; D000512:Alpha Particles / Q000009:adverse effects*; D024201:Bystander Effect / Q000528:radiation effects*; D002467:Cell Nucleus / Q000528:radiation effects; D004307:Dose-Response Relationship, Radiation; D005720:Gamma Rays / Q000009:adverse effects*; D006801:Humans; D008214:Lymphocytes / Q000528:radiation effects*; D048629:Micronuclei, Chromosome-Defective / Q000528:radiation effects*; D015162:Micronucleus Tests