Survival and DNA damage in Chinese hamster V79 cells exposed to alpha particles emitted by DNA-incorporated astatine-211

Radiat Res. 1998 Sep;150(3):263-8.


Asynchronous Chinese hamster V79 lung fibroblasts were incubated at 37 degrees C for 30 min with the thymidine analog 5-[211At]astato-2'-deoxyuridine (211AtdU, exposure from DNA-incorporated activity) or with [211At]astatide (211At-, exposure from extracellular activity), and DNA-incorporated activity was determined. The 211AtdU content in cellular DNA increased as a function of extracellular concentration. Incorporation of 211At- was less than 1% of that of 211AtdU. After exposure, cells were frozen in the presence of 10% DMSO. One month later, survival was determined by the colony-forming assay, and DNA double-strand breaks (DSBs) were measured by the neutral elution method (pH 9.6). The survival curve for 211AtdU was biphasic (D37 = 2.8 decays per cell), reflecting killing of 211At-DNA-labeled cells and of unlabeled cells irradiated by 211At in neighboring labeled cells. The toxicity of 211At- decaying outside the cell (30-min exposure) was negligible. Analysis of the survival curve produced a D0 of 1.3 decays/cell for 211At-labeled cells. The yield of DSBs from the decay of DNA-incorporated 211At was compared with that from DNA-incorporated 125I. Each decay of 211At produced at least 10 times the number of DSBs as that obtained per 125I decay. The extreme radiotoxicity of DNA-incorporated 211AtdU seems to be associated with considerable damage to the mammalian cell genome.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Astatine / pharmacokinetics*
  • Cell Survival / radiation effects
  • Cells, Cultured / metabolism
  • Cells, Cultured / radiation effects
  • Colony-Forming Units Assay
  • Cricetinae
  • Cricetulus
  • DNA / metabolism
  • DNA / radiation effects
  • DNA Damage*
  • Fibroblasts / cytology
  • Fibroblasts / metabolism
  • Fibroblasts / radiation effects*
  • Idoxuridine / analogs & derivatives*
  • Idoxuridine / pharmacokinetics


  • 5-astato-2'-deoxyuridine
  • DNA
  • Idoxuridine
  • Astatine