FIG. 2.
Humoral immune response in vCP 250 and vCP1420 ALVAC-immunized macaques. (a) Antibody titers to HIV-1IIIB gp140 protein were measured by ELISA in group A, group B, and group C animals on designated weeks after immunization on weeks 26, 52, 78, 225, and 233. (b) Anti-Tat antibody titers in the serum were measured on weeks 223, 227, and 234 after Tat protein boost in ALVAC-gp120 and ALVAC-gp160 animals. The minimum dilution of serum tested in the assay was 1:25. Values are expressed as mean antibody titers ± the standard errors from six animals from each group. (c) Neutralization of SHIVHXB2 was measured in MT2 cells in the presence of sera from groups A, B, and C macaques collected on weeks 28, 54, 80, and 234. The lowest dilution of serum tested in the assay was 1:10. The results are expressed as dilution of serum inhibiting 50% of infection in MT2 cells and are expressed as mean titers ± the standard errors from six animals of each group.