Figure 2.
HA307–319 tetramer identification of antigen-specific cells in relation to CFSE fluorescence. Nylon wool–purified T cells, labeled with CFSE before culture with autologous adherent cells and antigen, were stained on day 7 with PE-labeled HA307–319 tetramer and analyzed subsequently by flow cytometry. Each row shows cells from a different stimulating antigen for 2 different individuals: (a) 10 μg/mL HA307–319 peptide, (b) whole influenza vaccine containing 11 μg/mL HA, (c) whole TT at a maximally stimulating dose. In all panels cells are gated on forward and side scatter, the vertical axis shows PE fluorescence of the HA307–319 tetramer, and the horizontal axis shows CFSE fluorescence over a 4-decade logarithmic scale. In addition, the horizontal axis shows the corresponding number of cell divisions, with “P” depicting the undivided parent population. This scale was calculated from the distinct CFSE fluorescence peaks produced by polyclonal stimulation with PHA and IL-2 as described in Methods. Percentages shown in the margins of each panel represent the percent of total cells present in each quadrant. The panels depict results from representative individual experiments.