PURPOSE: To investigate whether delayed chromosomal instability arises in human peripheral T lymphocytes exposed in vivo to gamma-irradiation. MATERIALS AND METHODS: Long-term cultures were established from lymphocytes obtained from subjects involved in the radiological accident in Estonia in 1994. Two individuals exposed to a high dose, one individual with low exposure and one apparently unexposed person were studied. Two Estonian controls not involved with the accident were also analysed. Cells were grown for 6-42 days and chromosomal aberrations were assessed from G-banded metaphases. In addition, FISH chromosome painting analysis was performed on short-term cultures established from whole blood. RESULTS: No obvious sign of chromosomal instability was observed in the in vivo follow-up of the frequencies of chromosomal aberrations in lymphocytes of radiation accident victims performed by the FISH technique (48 h cultures established at different time intervals after the exposure). However, when the lymphocytes were cultured long term in vitro, chromosomal instability was observed. There was no dose-response, and the appearance of chromosomally unstable cells in long-term cultures was also observed in a subject exposed to a dose of less than 0.1 Gy. Moreover, in contrast with previous findings, chromosomal instability was also observed in cells from non-exposed control individuals. The chromosomal changes observed in the controls were less complex than the aberrations in the cultures derived from individuals exposed to high doses. CONCLUSIONS: Chromosomal instability was observed in long-term cultures of donors with in vivo exposure to gamma-radiation. No dose-response was apparent. However, in contrast with previous findings, signs of chromosomal instability were observed also in long-term cultures from non-exposed controls. Further studies are needed to assess possible inter-individual differences in the induction of chromosomal instability.
PURPOSE: To investigate whether delayed chromosomal instability arises in human peripheral T lymphocytes exposed in vivo to gamma-irradiation. MATERIALS AND METHODS: Long-term cultures were established from lymphocytes obtained from subjects involved in the radiological accident in Estonia in 1994. Two individuals exposed to a high dose, one individual with low exposure and one apparently unexposed person were studied. Two Estonian controls not involved with the accident were also analysed. Cells were grown for 6-42 days and chromosomal aberrations were assessed from G-banded metaphases. In addition, FISH chromosome painting analysis was performed on short-term cultures established from whole blood. RESULTS: No obvious sign of chromosomal instability was observed in the in vivo follow-up of the frequencies of chromosomal aberrations in lymphocytes of radiation accident victims performed by the FISH technique (48 h cultures established at different time intervals after the exposure). However, when the lymphocytes were cultured long term in vitro, chromosomal instability was observed. There was no dose-response, and the appearance of chromosomally unstable cells in long-term cultures was also observed in a subject exposed to a dose of less than 0.1 Gy. Moreover, in contrast with previous findings, chromosomal instability was also observed in cells from non-exposed control individuals. The chromosomal changes observed in the controls were less complex than the aberrations in the cultures derived from individuals exposed to high doses. CONCLUSIONS: Chromosomal instability was observed in long-term cultures of donors with in vivo exposure to gamma-radiation. No dose-response was apparent. However, in contrast with previous findings, signs of chromosomal instability were observed also in long-term cultures from non-exposed controls. Further studies are needed to assess possible inter-individual differences in the induction of chromosomal instability.
Authors: E Janet Tawn; Caroline A Whitehouse; Jeanette F Winther; Gillian B Curwen; Gwen S Rees; Marilyn Stovall; Jørgen H Olsen; Per Guldberg; Catherine Rechnitzer; Henrik Schrøder; John D Boice Journal: Mutat Res Date: 2005-06-06 Impact factor: 2.433
Authors: Mark P Little; Richard Wakeford; E Janet Tawn; Simon D Bouffler; Amy Berrington de Gonzalez Journal: Radiology Date: 2009-04 Impact factor: 11.105