Figure 2. Immune responses in the vaccinated/challenged macaques.

(A) ELISPOTs were performed using HIV_Ba-L, HIV_SF162, and HIV_89.6 Tev peptide pools for the stimulation of macaque blood. ELISPOT responses were also obtained using Concanavalin A, a stimulus to control for cell viability (data not shown).

Antibody titers to Tev (B), Tat(C), Rev(D), and the pooled HIV_Ba-L, SHIV_SF162P3, and SHIV_89.6P Envelope proteins (E). The arrows refer to DNA immunizations (weeks 0, 4, 8), protein boosts (weeks 12, 18), and challenge exposure (week 22); titers to the purified Tev, Tat, Rev, and pooled HIV_Ba-L, HIV_SF162P3, and HIV_89.6P Envelope proteins. The weeks 0, 2, 6, and 10 refer to the weeks post challenge (p.c.). Data from control macaques are not shown.

(F) Overlapping peptides of the entire HIV_89.6 Tev protein whose sequence is depicted in Fig. 1B were used with the sera (1:100 dilution) of the macaques after immunization (weeks 10, 19) and challenge exposure (weeks 2, 5 p.c.) in some of the vaccinated and control macaques. The area included in the dotted line area defines the V1 peptides (16 to 23), proceeded by the peptides derived from the first exon of Tat and followed by the peptides derived from the second exon of Rev.

(G) Sera (1:100 dilution) of all immunized macaques after challenge exposure (weeks 2, 5 p.c.) and the two control macaques L915 and M320 were reacted with overlapping peptides 16–28 for the 89.6 V1.

(H) Amino acid sequences of the 21-24 overlapping peptides recognized by the sera of macaques M308, M316, and M490 and M607 within the V1 region of SHIV_89.6P.

(I): Sera (1:100 dilution) of the immunized macaques M218, M308, M316, and M490 before and after challenge exposure (weeks 10 and 19 and 2, 5 respectively) and the two control macaques. L915 and M320 were reacted with overlapping peptides 16–28 for the SF162 V1 region.