FIG. 1.

Vaccine-elicited cellular immune responses to SIVmac251 Gag and HIV-1 89.6P Env. PBMCs were isolated at weeks 10 (panel 1, postprime), 28 (panel 2, postboost 1), 45 (panel 3, postboost 2), and 64 (panel 4, day of challenge) postimmunization and assessed in IFN-γ ELISPOT assays following in vitro exposure to peptide pools spanning SIV Gag and HIV-1 89.6P Env proteins. The bars represent the means ± standard error of the means (error bars) of SFC responses to individual viral proteins for six monkeys in each group. PBMCs of the control-vaccinated monkeys demonstrated SFC responses of less than 20/10⁶ PBMC.