Accession Number:

AD0667231

Title:

EFFECTS OF TOTAL-BODY IRRADIATION ON THE IMMUNE ELIMINATION OF I131-HORSE SERUM ALBUMIN IN LAF1 MICE,

Descriptive Note:

Corporate Author:

NAVAL RADIOLOGICAL DEFENSE LAB SAN FRANCISCO CALIF

Report Date:

1968-02-08

Pagination or Media Count:

31.0

Abstract:

The effect of total-body irradiation on the primary antibody response to horse serum albumin in mice was studied. Mice were irradiated with doses ranging from 100 to 400 R and were immunized 24 hours later. At various time intervals thereafter, the antibody response was determined by measuring the elimination of a tracer dose of I131 horse serum albumin from the plasma. From the results of these measurements, the induction period, the slope of the elimination curve and the T99 was calculated. The immune response was expressed in terms of T99, i.e., the time hours required for the elimination of 99 of a given amount of antigen from the plasma. The radiation effects observed consisted in a delay of the onset of immune elimination and a decrease in the rate of appearance of anti-bodies in the plasma. The relationship between T99 and the time of injection of the tracer dose days after immunization in mice irradiated with doses up to 300 R was similar to that observed in non-irradiated immunized mice. However, the initial period during which T99 remained constant was lengthened in mice exposed to 200 and 300 R. In addition, the subsequent linear decrease of T99 with time occurred at a lower rate. The relative immune response, based on the T99 observed when the tracer dose was injected 7 days after immunization, provided a basis for comparison of the radiation injury to the immune system at the various dose levels. When the relative immune response was plotted against the radiation dose, a linear dose-effect curve was obtained. The radiation dose required to obtain a 50 depression of the immune response was found to be 175 R. Author

Subject Categories:

  • Radiobiology

Distribution Statement:

APPROVED FOR PUBLIC RELEASE