FIG. 4.
Proliferative responses stimulated in immunized animals. The spleen cells of vaccinated mice were restimulated with different concentrations of β-Gal for 4 days. Proliferation was assessed by measurement of [3H]thymidine incorporation. The results are expressed as the ratio between values (average of triplicates) from stimulated or nonstimulated samples (stimulation index). SEMs are indicated by vertical lines.