Radiation response of cell populations irradiated in situ and separated from a fibrosacroma
A cell separation system involving the centrifugation of cells in linear density gradients of Renografin provides a useful method for the in vivo study of the various clonogenic subpopulations comprising a solid tumor. Following this procedure, two selected elonogenic cell populations were separated from a murine fibrosarcoma after exposure in situ to ionizing radiation. The clonogenicity of each population (Band 2,anti rho = 1.08 g/cm/sup 3/ and Band 4,anti rho = 1.14 g/cm/sup 3/) was determined using a lung colony assay. Survival curves were constructed and compared with data from an unseparated population. The Band 2 population, when irradiated in air-breathing animals, had a relatively large fraction of sensitive cells and a more resistant component whose response was apparent at doses greater than 1000 rad. The D/sub 0/ of this resistant fraction was 459 rad. Comparing the survival curves of Band 4 and unseparated cells, the values of D/sub 0/ were similar (403 and 413 rad, respectively), but the parameters describing the shoulder region of these curves differed significantly (Band 4, D/sub q/ = 644 rad, n = 5.2; and unseparated cells, D/sub q/ = 344 rad, n = 2.3). Under conditions of acute hypoxia, Band 2 cells became significantly more radioresistant. No change in radiation sensitivity was apparent, however, for Band 4 cells. It was concluded that the Band 4 population probably consisted primarily of chronically hypoxic cells since conditions of acute hypoxia had little, in any, effect on their response to radiation.
- Research Organization:
- Univ. of Texas Systems Cancer Center, Houston
- OSTI ID:
- 7343030
- Journal Information:
- Radiat. Res.; (United States), Vol. 66:3
- Country of Publication:
- United States
- Language:
- English
Similar Records
Radiation sensitivity of murine fibrosarcoma cells separated by centrifugal elutriation
Heterogeneity in cytokinetic, clonogenic, and radiation response induced by nutrient deprivation
Related Subjects
FIBROSARCOMAS
BIOLOGICAL RADIATION EFFECTS
TUMOR CELLS
RADIOSENSITIVITY
ANOXIA
CESIUM 137
GAMMA RADIATION
MICE
WHOLE-BODY IRRADIATION
ALKALI METAL ISOTOPES
ANIMAL CELLS
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL EFFECTS
CESIUM ISOTOPES
DISEASES
ELECTROMAGNETIC RADIATION
EXTERNAL IRRADIATION
IONIZING RADIATIONS
IRRADIATION
ISOTOPES
MAMMALS
NEOPLASMS
NUCLEI
ODD-EVEN NUCLEI
RADIATION EFFECTS
RADIATIONS
RADIOISOTOPES
RODENTS
SARCOMAS
VERTEBRATES
YEARS LIVING RADIOISOTOPES
560152* - Radiation Effects on Animals- Animals