Figure 5. The GM-CSF genetic adjuvant increases both the magnitude and breadth of mucosal T cell responses elicited in the lungs and guts following PMED HA DNA vaccination.

HA-specific T cell responses in the (A) lung and (B) gut mucosa of macaques were determined by IFN-γ ELISpot assay 4–11 weeks after the final vaccination with HA DNA (solid bars) or HA DNA+GM-CSF (hatched bars). Individual bars represent the peak number of HA-specific IFN-γ T cells detected in the jejunum and lung tissue of individual animals 4–11 weeks after the final vaccination. (C) Breadth of the IFN-γ T cell response in PBMC, lung, and gut. HA-specific T cell responses in the indicated tissues were measured using a standard IFN-γ ELISpot assay with 6 individual pools of overlapping peptides (11 amino acid overlaps, 103 15-mers per pool) comprising the entire amino acid sequence of the influenza A/New Caledonia/20/99 HA protein. The percent contribution of each peptide-pool specific response to the total response was determined by dividing the mean number of IFN-γ spot forming cells (SFC) measured against each individual peptide pool by the sum of the response against all peptide pools. Results represent the average of 2 time-points tested after the 3^rd DNA dose (weeks 19 and 23). *Measurement below positive threshold level for the assay.