The Effect of X-Ray Radiation on the Formation of Typhus Fever Antibodies

Abstract

Male guinea-pigs 300—350 Gm. in weight were subjected to 100, 150 and 200 roentgen total body X-radiation in a multiple and single exposures.

Irradiated as well non-irradiated animals were infected with minimal infected dose of R. provvazeki suspension.

1. The animals exposed to two hundred roentgen 5 days before or five days after the whole-body X-radiation showed longer febrile reaction and more abundant rickettsiaemia than in control non-exposed animals.

The difference between irradiated and control animals was not statistically significant when a dose of 100 or 150 roentgen was used. Hundred and hundred fifty roentgen whole-body X-radiation inhibited after infection with R. prowazeki the antibody response only in some animals.

It was much more significant in the animals subjected to 200 r. two days before and 5 days after infection. Four out of six with 200 r. irradiated animals showed no immunity when challenged 6 weeks after infection with two minimal infected doses of R. prowazeki. Two out of those four animals without immunity after infection showed C. F. titters 1:5 and 1 : 10.

2. The subcutaneous vaccination of animals with 3 doses of 0,5 ccm. Cox typhus-vaccine 7 days apart produced 5 times higher C. F. titters in non-irradiated animals after three weeks, fourteen times five weeks and 18 times six weeks after vaccination. Single animals had no C. F. antibodies when irradiated with 200 r. some days before and after radiation.

3. The radiation has a very negative effect at the “booster” response. When the animals were exposed to whole body X-radiation with 200 r. two months before “booster” dose, the C. F. antibody response was three times higher after the booster dose of vaccine. When the animals were irradiated with 200 r. the same day they got »booster« dose of vaccine, the animals showed no rise of C. F. antibodies when measured the day before and one month after the administration of “booster” dose. The “booster” dose was given three months after the primary vaccination against typhus fever.