Protection and Polyfunctional T Cells Induced by Ag85B-TB10.4/IC31® against Mycobacterium tuberculosis Is Highly Dependent on the Antigen Dose
Figure 3
Ag85B and TB10.4 specific T cells are polyfunctional.
(A). Cytokine profiles of H4 specific CD4 T cells were determined by first dividing the CD4 T cells into IFN-γ positive (+) or IFN-γ negative (-) cells. Both the IFN-γ+ and IFN-γ− cells were analyzed with respect to the production of TNF-α and IL-2. The numbers in the quadrant gates of the plots denominates each distinct population based on their cytokine production and is color coded as shown. (B–D) The pie charts are grouped after vaccination dose and colour coded according to the cytokine production profile and summarizes the fractions of the CD4+ T cell response (out of the antigen specific CD4 T cells) that are positive for a given cytokine production profile. Every possible combination of cytokines is shown on the x-axis of the bar chart and the percentage of Ag85B, TB10.4 or Ag85B-TB10.4 (H4) specific CD4+ T cells expressing any combination of cytokines is given for each immunization group. The antigen used for in vitro stimulation of the PBMC's is indicated. No responses were seen in the CD8+ T cell subset. (E) The mean fluorescence intensity (MFI) of IFN-γ in the subpopulations expressing this cytokine from animals vaccinated with either 0.5 µg H4 or 5 µg H4. Results are representative of two independent experiments.