| Abstract: | Five experiment series were applied to 38 calves, aged between two-and-a-half and four months, using whole-body exposure to X-ray treatment based on median lethal doses (MLD) between 1.2 Gy and 1.7 Gy. Various methods of immunisation were simultaneously applied, and their effects on irradiation-caused response of gamma globulin concentrations in blood serum were studied. Gamma globulin levels were determined by Kunkel's zinc sulphate turbidity test. Immunisation applied between 14 and 21 days prior to irradiation resulted on obvious stimulation of gamma globulin production. In two experiments with parenteral antigen application, gamma globulin levels increased through about 14 days in apparently irradiated animals declined, after that period of time, but they continued to rise in really irradiated probands. A high lethal dose of 1.7 Gy, however, was followed by significant drop, three weeks after irradiation, that is in concomitance with the climax of the radiation syndrome. When 1.5 Gy were used, rise in gamma globulin concentration was recordable also following oral administration of antigen. Response of irradiated animals was even more clearly pronounced by secondary reaction of antibody formation, following booster action due to experimental infection with homologous germs. The stimulating effect of irradiation upon gamma globulin levels in blood serum, when oral or parenteral immunisation had taken place, prior to irradiation, has been attributed to reaction of the immune-globulin producing system to the release of tissue proteins or tissue antigens. Immunisation, prior to irradiation, stimulated the immunological system which underwent stronger regeneration, after irradiation, or had obviously acquired higher resistance to radiation. |
