Results of Investigation of the Effect of Cosmic Radiation and Other Factors of Cosmic Flight on Lysogenic Bacteria and Human Cell Cultures.

摘要

Single-layer cultures of normal human cells (fibroblasts and amniotic cells) and human cancer cells (Hela strain), together with cultures of lysogenic bacteria (E. coli K-12), have been consistently used as radiation indicators on Soviet spacecraft. Results of these experiments show that repeated exposure of a culture of Hela cells to spaceflight factors on the 'Vostok-4' and 'Vostok-6' flights produced changes in experimental cells as compared with laboratory controls and with Hela cells exposed on one spaceflight only. A longer latent period of recovery of growth capacity and other characteristics were noted in twice-flown cultures. In addition, the coefficient of proliferation for Hela cells exposed on both 'Vostok-4' and 'Vostok-6' was one-half that for intact controls and for Hela cells exposed to spaceflight only once. These data suggest that spaceflight factors have a direct dependence of biological effect on length of spaceflight exposure has not been established in experiments with the other radiation indicator, the lysogenic bacteria E. coli K-12. It is interesting to note that when the same Hela cells used on 'Vostok-4' and 'Vostok-6' were also exposed on 'Voskhod-1', a well-defined drop in the proliferation coefficient was observed in comparison with intact cultures. Other reliable differences were also found between intact controls and thrice-exposed cultures. However, no reliable differences could be detected between thrice-exposed Hela cells and a control strain used only on 'Vostok-6'. It is suggested that the biological effect of spaceflight may be the result of the combined influence of radiation, vibration, and weightlessness.