Figure 2.

CD4⁺ T cell Responses Measured by intracellular cytokine staining for interferon (IFN)–γ and interleukin (IL)–2. The percentage of the CD3⁺/CD4⁺ population expressing either cytokine following exposure to Env peptides is depicted. IFN-γ– and IL-2–specific responses are shown for each vaccination group. Note that for group 5, day 70 represents 2 weeks after receipt of the second protein dose, whereas day 182 for the DNA-primed groups represents 2 weeks after receipt of the first protein boost.