Lethal response of HeLa cells to x irradiation in the latter part of the generation cycle

Journal Article · Thu Apr 01 00:00:00 EST 1976 · Biophys. J.; (United States)

DOI:https://doi.org/10.1016/S0006-3495(76)85690-1· OSTI ID:7346937

Griffith, T D; Tolmach, L J

The age-response for the killing of HeLa S3 cells by x rays during the latter part of the generation cycle has been examined in detail. As synchronous cells move from the G1/S boundary through S phase, the relatively high sensitivity of late G1 cells gradually decreases; minimum sensitivity is reached in mid-S and maintained during the remainder of that phase. The response of cells as they progress from S to the point in G2 at which they are temporarily arrested by radiation (or by inhibitors of protein synthesis) was measured in populations free of both S phase cells and late G2 cells that had passed the arrest point: cells retain their high resistance from early G2 up to the arrest point. The response of G2 cells that have passed the arrest point before being irradiated was examined by exposing randomly growing cultures to x rays and collecting cells periodically thereafter, as they entered mitosis. Survival values very close to those of sensitive mitotic cells were found in the 2 h period after irradiation during which unarrested cells continued to reach mitosis. Values typical of late S/early G2 were found only after cells that had been arrested began arriving at mitosis. Thus, HeLa S3 cells undergo an abrupt increase in sensitivity at or near the arrest point. The sensitivity to a second irradiation of cells arrested in G2 by a conditioning x-ray dose increases rapidly in the early part of the arrest period.

• Research Organization: Washington Univ., St. Louis, MO (United States)
• OSTI ID: 7346937
• Journal Information: Biophys. J.; (United States), Vol. 16:4
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
CELL CYCLE
RADIOSENSITIVITY EFFECTS
HELA CELLS
BIOLOGICAL RADIATION EFFECTS
CELL CULTURES
LETHAL IRRADIATION
X RADIATION
BIOLOGICAL EFFECTS
ELECTROMAGNETIC RADIATION
IONIZING RADIATIONS
IRRADIATION
RADIATION EFFECTS
RADIATIONS
560121* - Radiation Effects on Cells- External Source- (-1987)