FIG. 5.

CTLA-4 expression by gag-specific CD4⁺ T cells during PHI. (A) Following the stimulation of whole blood from a healthy adult control with CMV lysate or from a subject during PHI with either CMV lysate or Gag peptides, in the intracellular cytokine assay, CD4⁺ T cells were simultaneously stained with monoclonal antibodies to IFN-γ and CTLA-4. Representative histograms are shown. (B) Overall results for all cohorts are shown with the number of subjects in each cohort. The results for CTLA-4⁺ cells are expressed as percentages of IFN-γ⁺ CD4⁺ T cells. Box plots depict the 10th, 25th, median, 75th, and 90th percentiles.