Accession Number:

ADA053204

Title:

Radiobiological Aspects of High Altitude Flight: Relative Biological Effectiveness of Fast Neutrons in Suppressing Immune Capacity to an Infective Agent,

Descriptive Note:

Corporate Author:

FEDERAL AVIATION ADMINISTRATION WASHINGTON D C OFFICE OF AVIATION MEDICINE

Report Date:

1978-02-01

Pagination or Media Count:

8.0

Abstract:

We investigated the relative biological effectiveness RBE of fast neutrons compared with X-rays in impeding development of immunity to an infective agent, the intestinal cestode Hymenolepis nana. Mice were irradiated with neutrons or X-rays and 2 days later given an immunizing dose of H. nana eggs. After another 2 days, the mice received a challenge dose of the eggs. Challenge egg doses were also given to sham-irradiated unimmunized and immunized controls. All mice were killed 90 to 92 hours after challenge, and the H. nana larvae cysticercoids that developed in the intestinal tissue were counted. An increased cysticercoid count in the irradiated mice, as compared with the count in unirradiated immunized controls, reflects suppression of immune capacity by the radiation. The results indicate a neutron RBE of 4 at 50 and 101 rad. Author

Subject Categories:

  • Radiobiology
  • Microbiology

Distribution Statement:

APPROVED FOR PUBLIC RELEASE