Figure 8. Efficacy of differentially programmed RhCMV vectors.

(A-E) Assessment of the outcome of SIV infection after repeated, limiting dose SIV_mac239 challenge (see Fig. 6A) of the designated vaccine groups by longitudinal analysis of plasma viral load (left panels) and de novo development of SIVvif-specific CD4⁺ (middle panels) and CD8⁺ (right panels) T cell responses. RMs were challenged until the onset of any sustained above-threshold SIVvif-specific T cell response, with the SIV dose administered 2 or 3 weeks prior to the initial response detection considered the infecting challenge (week 0). The n in each panel reflects the total number of RMs with such documented take of SIV infection during the challenge period. RMs with sustained viremia were considered non-protected (black); RMs with no or transient viremia but demonstrating sustained above-threshold SIVvif-specific T cell responses were considered protected (red) (6–8). Binomial exact p-values are shown where the proportion of protected RMs in a vaccine group differs significantly from the unvaccinated group. (F) Bone marrow (BM), peripheral lymph node (LN) and peripheral blood mononuclear cell (PBMC) samples from all vaccine-protected RMs (red) and 2 non-protected RMs (black) for comparison (left panel), collected from between day 28 and 56 post-SIV infection, were analyzed by nested, quantitative PCR/RT-PCR for cell-associated SIV DNA and RNA. The dotted line indicates the threshold of detection (B.T. = below threshold) with data points below this line reflecting no positive reactions across all replicates.