FIG. 4.

Codominance of the Gag p11C and Env p41A CTL epitopes elicited by DNA vaccination of rhesus monkeys. Seven Mamu-A∗01⁺ rhesus monkeys were immunized by separate injections with two purified pV1R plasmids expressing either SIVmac239 Gag or HIV-1 89.6P Env. A total of 5 mg of each plasmid was inoculated i.m. at separate sites, and the animals were boosted at 4 and 8 weeks. Four monkeys also received a plasmid expressing an interleukin-2-immunoglobulin fusion protein (4). CTL responses to the SIV Gag p11C and HIV-1 Env p41A epitopes were measured 4 weeks (A to C) and 16 weeks (D to F) after primary immunization. Epitope-specific CTLs were quantitated as described in the legend to Fig. 1 by tetramer staining of PBL in freshly isolated whole blood (A and D), tetramer staining of peptide-stimulated PBL (B and E), and functional specific lysis by peptide-stimulated PBL (C and F). Tetramer staining of freshly isolated PBL and peptide-stimulated PBL utilizing a control Mamu-A∗01/Pol p68A (STPPLVRLV) tetramer was consistently <0.1% (data not shown). Results shown here are representative of assays performed at least three times.