An α-particle irradiator, enabling high-precision irradiation of cells for in vitro studies, has been constructed. The irradiation source was a (241)Am source, on which well inserts containing cancer cells growing in monolayer were placed.
The total radioactivity, uniformity, and α-particle spectrum were determined by use of HPGe detector, Gafchromic™ dosimetry film, and PIPS(®) detector measurements, respectively. Monte Carlo simulations were used for dosimetry. Three prostate cancer (LNCaP, DU145, PC3) and three pancreatic cancer (Capan-1, Panc-1, BxPC-3) cell lines were irradiated by α-particles to the absorbed doses 0, 0. 5, 1, and 2 Gy. For reference, cells were irradiated using (137)Cs to the absorbed doses 0, 1, 2, 4, 6, 8, and 10 Gy. Radiation sensitivity was estimated using a tetrazolium salt-based colorimetric assay with absorbance measurements at 450 nm. The relative biological effectiveness for α-particles relative to γ-irradiation at 37% cell survival for the LNCaP, DU145, PC3, Capan-1, Panc-1, and BxPC-3 cells was 7. 9 ± 1. 7, 8. 0 ± 0. 8, 7. 0 ± 1. 1, 12. 5 ± 1. 6, 9. 4 ± 0. 9, and 6. 2 ± 0. 7, respectively. The results show the feasibility of constructing a desktop α-particle irradiator as well as indicate that both prostate and pancreatic cancers are good candidates for further studies of α-particle radioimmunotherapy.
Cancer biotherapy & radiopharmaceuticals. 2015 Nov [Epub]
Jenny Nilsson, Monika Posaric Bauden, Jonas M Nilsson, Sven-Erik Strand, Jörgen Elgqvist
1 Department of Radiation Physics, Gothenburg University , Gothenburg, Sweden . , 2 Department of Surgery, Institution of Clinical Sciences, Lund University , Lund, Sweden . , 3 Department of Medical Radiation Physics, Lund University , Malmö, Sweden . , 4 Department of Medical Radiation Physics, Institution of Clinical Sciences, Lund University , Lund, Sweden . , 4 Department of Medical Radiation Physics, Institution of Clinical Sciences, Lund University , Lund, Sweden .