Fragmentation of SIV-gag Vaccine Induces Broader T Cell Responses
Figure 4
Fragmentation augments SIV-gag specific T cell responses.
Purified naive T cells were primed and boosted weekly with Ad5-transduced DC expressing non-ubiquitinated full-length SIV-gag (0xUb), ubiquitinated full-length SIV-gag (1xUb), or ubiquitinated SIV-gag mini genes (MF1–MF7) separately. SIV-specific T cell responses against 125 overlapping SIV-gag peptides were measured using IFN-γ ELISPOT assays on day 21 post initial DC-T cell priming. Spot forming cells (SFC) per one million T cells in cultures that were initially stimulated with 0xUb (closed bars), 1xUb (open bars), or SIV-gag mini fragments (gray bars) are shown for a representative sample in the left panel, where each graph from top to bottom shows responses against individual SIV peptides spanning the mini-fragment regions MF1 to MF7. The data from 4 independent samples are summarised in the right hand side tables where strong responses (>600 SFC/106 cells) are shown in black and medium responses (>400 SFC/106 cells) are highlighted in gray. All data were corrected for background IFN-γ production in response to mock stimulations. Note that sample A represents CD8 specific T cell responses whereas samples B, C, D represent responses using a mixture of CD4 and CD8 T cells. Sequences of all 125 peptides numbered as in these experiments may be found at https://www.aidsreagent.org/search_reagents.cfm.