Figure 3: Anti-SIV efficacy of ddCyCMV/SIV vectors.

(A) Kaplan-Meier curve displaying number of challenges needed for SIV acquisition in the eight ddCMV/SIV vaccinated MCM (black) and eight unvaccinated controls (blue). (B) Measurements of SIV RNA per mL plasma in ddCMV/SIV vaccinated and control MCM post-infection. The last challenge prior to a positive viral load and/or detection of a T cell response against SIV proteins not in the vaccine was determined as the challenge leading to successful infection. Red lines depict protected, vaccinated, MCM; black lines depict unprotected, vaccinated MCM; and blue lines depict unvaccinated, control MCM. Dashed line = limit of quantification at 15 copies/mL. (C) SIV Env- and (D) SIV Vif-specific CD8+ T cell responses post-infection. Responses are following subtraction of response to no stimulation for each animal at each time point. Colors match those in panel B, but for clarity only display the mean response magnitude for the unprotected vaccinated MCM and unvaccinated control MCM. (E) Cell associated viral DNA and (F) viral RNA loads from bone marrow, peripheral lymph node (axillary or inguinal), mesenteric lymph node, and spleen biopsies. Values above the limit of detection are filled while values below the limit of detection are not. Non-circle symbols indicate the specified protected MCM. DNA Minimum Threshold: 0.28 copies DNA/10⁶cells. RNA Minimum Threshold: 0.51 copies RNA/10⁶cells. (G) Anatomical source and number of cells from protected, ddCyCMV/SIV vaccinated MCM that were used for adoptive transfer studies to SIV naïve MCM. (H) Plasma viral loads in four MCM that received the cells listed in panel G. Viral loads depict time post-infection (post-transfer) and each donor/recipient pair is listed on the right. Dashed line = limit of quantification at 50 copies/mL. See also Figure S6 and Table S2.