Radiosensitivity of immune responses to 2.2 BeV protons, gamma-radiation and x-radiation

Autor: Stoner, R. D., Straub, R. F., Moore, W. H., Jesseph, J. E.
Zdroj: Radiation Effects and Defects in Solids; January 1969, Vol. 2 Issue: 2 p97-104, 8p
Abstrakt: Mice were exposed to sublethal radiation with either 2.2 BeV protons, γ-radiation or X-radiation to compare radiation-induced repression of primary and secondary antibody responses and radiationenhanced susceptibility to fatal anaphylactic shock. Five animals at a time were exposed in tandem in a 2.5 cm I.D. Lucite tube to a parallel beam of protons from the Cosmotron. A comparison of doses required to produce 50 per cent repression of normal primary tetanus antitoxin responses indicates that exposure to 1.15 × 109/cm2 protons (38 rads) is as effective in repressing primary responses as 100 rads of γ-radiation and X-radiation. Proton doses of the order of 5 × 100/cm2 (165 rads) and 300 rads of γ-radiation and X-radiation were needed to repress secondary antibody responses by 50 per cent of normal. An average RBE of 2.5 (S.D., 0.58) was obtained for primary responses, whereas an average RBE of 1.5 (S.D., 0.22) was found for secondary responses. Exposure to 4 × 109/cm2 protons (132 rads) and 350 rads of γ-radiation resulted in a similar degree of radiationenhanced susceptibility to fatal anaphylaxis with an RBE of 1.5.
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