ABSTRACT: Selective irradiation by an ionizing particle of a targeted cell organelle may disclose such mechanisms as signal transactions among cell organelles and cell-to-cell communication in the processes toward an endpoint observed. Bystander effect, existence of which has been clearly evidenced by application of the particle microbeam to biological experiments suggests potential deviation from the conventional risk estimation at low particle fluence rates, such as in an environment of space radiation in the International Space Station. To promote these studies, we started the construction of a microbeam facility (named single-particle irradiation system to cell [SPICE]) by using our HVEE Tandem accelerator (3.4 MeV proton and 5.1 MeV 4He2+). For our primary goal, "irradiation of a cell organelle with a single particle with a position resolution of 2 [mu]m in a reasonable irradiation time," special features are considered. Usage of a triplet Q magnet for focusing the beam to micrometer levels is an outstanding feature compared to facilities of other institutes. Other features are almost similar to those of other institutes. Those are precise position control of a cell dish holder, design of the cell dish, data acquisition of the microscopic image of a cell organelle (cell nucleus), data processing, reliable particle detection, software and hardware to integrate all these related data, and a system to control and irradiate a targeted spot with an exactly determined number of particles.
International Congress Series. 1258:281-285.