FIG. 4.

Cellular immune responses in mice after vaccination with either nCD or rCD using AdDP as the adjuvant. (A) Proliferation was assessed after 4 days of in vitro restimulation of spleen cells in the presence of the CD protein by measuring [³H]thymidine incorporation (cpm). The data are mean numbers of cpm for triplicate samples after subtraction of background values for nonstimulated cells. (B and C) Total splenocytes were incubated for 40 h in the presence of either nCD or rCD, and the numbers of IL-2-producing cells (B) and IL-4-producing cells (C) were determined by ELISPOT assays. (D) CD4⁺-depleted splenocytes were incubated for 16 h in the presence of either nCD or rCD, and the number of IFN-γ-producing cells was determined by an ELISPOT assay. The data in panels B, C, and D are presented as the numbers of spot-forming units (SFU)/10⁶ cells in stimulated samples after subtraction of the background value for nonstimulated cells. The error bars indicate standard errors of the means. Differences between the experimental groups were statistically significant at P values of <0.05 (one asterisk), <0.01 (two asterisks), and <0.001 (three asterisks).