Fig. 1.

Vaccine-induced immune responses in RM before SIVmac239 challenge. PBMC and sera were isolated from vaccinated RM at baseline (day 0) and during the course of 4 immunizations. PBMC were assessed for Gag(black), Pol(white), Nef(striped) or Env(grey) induced IFN-γ secretion by ELISpot analysis (A). Note the CMI responses induced during the course of multiple immunizations. No SIV CMI responses were detected in controls immunized with Ad5 [E1-, E2b-]-null. An IgG response (baseline-subtracted) was detected against gp120 env in vaccinated RM employing a quantitative ELISA technique (B). No antibody was detected against SIV-gag, pol, or nef.