Increase in IFNγ−IL-2+ Cells in Recent Human CD4 T Cell Responses to 2009 Pandemic H1N1 Influenza
Figure 3
Cytokine patterns of memory CD4 T cells specific for distinct influenza specificities.
PBMC were stimulated with pools of CA/09ni, NC/99ni, and conserved peptides and analyzed by ICS and flow cytometry. (A, top) The total influenza-specific responses (cells positive for all combinations of cytokine/chemokine) and individual TNFα, IFNγ, IL-2, and CCL4 responses were calculated as numbers per million total CD4 T cells after background subtraction. (A, bottom) The percent of the cytokine-producing cells was calculated from the numbers in A, top. (B) Mean frequencies from all subjects for each of the cytokine positive combinations were calculated from a Boolean analysis of cells secreting TNFα (T), IFNγ (G), IL-2 (2) and CCL4 (C) for CA/09ni (left), NC/99ni (middle), and conserved (right) peptides. The black arcs represent the proportion of the cytokine combinations that express IFNγ.