FIG. 3.

Proliferative responses to 10⁸ CFU of gamma-irradiated SRB51 by PBMC from elk vaccinated with saline, 1.2 × 10¹⁰ CFU of SRB51, or 0.8 × 10¹⁰ CFU of S19 (n = seven animals/treatment). Cells were incubated at 37°C and 5% CO₂ for 7 days and pulsed for 18 h with [³H]thymidine. The results are expressed as mean stimulation indexes. Means within a sampling time with different superscripts are significantly different (P < 0.05). The mean response of elk PBMC incubated in the absence of antigen was 1,991 ± 364 cpm. The mean response of elk PBMC incubated with 1 μg of pokeweed mitogen was 103,555 ± 7,550 cpm.