Elimination of I¹³¹-labelled heterologous antigen from the blood of chickens after total body X-irradiation

Abstract

A study was made on the effect of ionizing radiation upon the rate of elimination of I¹³¹. labelled human serum albumin (HSA I¹³¹) from the blood and upon antibody formation in chickens irradited with 1,2 00R(i.e.with LD₅₀) and injected with antigen 30 min, 6 days or 14 days after irradiation. The elimination curve from unirradiated control birds followed the typical three-phase pattern. The effect of irradiation was most marked with chickens injected with antigen 6 days after irradiation, resulting in an extension of the second phase with practically no third phase at all. Exposure to irradiation 30 min prior to antigen administration resulted in an extension of the second phase by 2 days as compared to the controls, with the onset of the third phase occurring on day 7. Irradiation 14 days prior to antigen administration resulted in an extension of the second phase by 1 day as compared to the controls, with the onset of the third phase occurring on day 6.

Elimination of HSA I¹³¹ in the second phase was more rapid than that of I¹³¹-labelled chicken serum albumin (CSA I¹³¹) no matter whether the chickens were irradiated or not. This suggests that the capacity of specific antigen uptake is not affected by irradiation.

Antigen elimination curves from control irradiated groups given CSA I¹³¹ followed the same pattern as that found in control unirradiated birds injected with homologous antigen.