Fig. 4.

CD8⁺ T cells responses one month post-vaccination. The activity of splenic T cells from C57BL/6 mice (n = 5) was measured one month post-vaccination with 10⁴ p.f.u. of the indicated viruses, or mock-vaccination with PBS in both ear pinnae. (a) The cytolytic activity of splenic T-cells against VACV strain WR-infected EL-4 target cells was determined by ⁵¹Cr release assay. Data are expressed as percentage specific lysis ± SEM. (b and c) The percentage of CD8⁺ T cells expressing IFNγ (b) or TNFα (c) was determined by intracellular cytokine staining. Data are expressed as percentage ± SD. Statistical analyses were performed using the Student’s t-test. ^*P < 0.05, ^**P < 0.01, ^***P < 0.001, ns: not significant. The experiments were conducted at least 3 times and the data shown are representative.