102 BIOLOGICAL EFFECTS OF LOW LEVEL EXPOSURES
Figure 5.3. Thymic weight as a function of dose and time after irradiation. Adapted from
Anderson and Hendry.18
body irradiation administered to rabbits at various times before or after
primary (Figure 5.5) or secondary (Figure 5.6) immunization with sheep
erythrocytes. As noted previously, the temporal relationship between irradi
ation and antigen injection appears critical to the generation of an aug
mented response. Also important, although apparently not as critical as
timing, are the character of the antigen; the radiation dose; the manner in
which the irradiation is administered; and the age, sex, and genetic compo
sition of the host.
Low-dose radiation can also be utilized to immunize animals against
Figure 5.4. Splenic weight as a function of dose and time after irradiation. Adapted from
Anderson and Hendry.18