The acute effects of ionizing radiation on antibody-producing cells (PFC) in mouse spleen during primary and secondary responses to sheep erythrocytes (SRC).

The acute effects of various doses of whole body X-radiation on the splenic PFC of mice responding to primary and secondary immunization with SRC were studied. The results showed that suppression of plaque-forming capacity occurred 2 hours after varying doses of X-rays and was very severe by 6 hours. No differences in sensitivity were seen at any stage of the primary or secondary response examined. This acute depressive effect showed that the maintenance of splenic PFC was highly sensitive to radiation and was associated with a severely reduced uptake of [H]thymidine into the spleen at the same time after irradiation. Since previous studies (Harris and Pelc, 1970) have shown that incorporation of [H]thymidine occurred in non-dividing cells in mouse spleen, it was concluded that this turnover of DNA was important for the development of the capacity of cells to produce specific antibodies and that the acute depressive effects of X-radiation on splenic PFC was primarily due to inhibition of this process.