FIG 9.
Plasmas from immunized monkeys show moderate ADCC and ADCVI activities. (A) ADCC activity. CEM.NKRCCR5 target cells coated with gp120 of isolate 1086 (left) or TV1 (right) were mixed with PBMCs at an E:T ratio of 30:1. A granzyme B substrate and dilution series of the plasma samples were added, and the cells were incubated and assessed by flow cytometry for viable cells showing granzyme B activity. The antibody titer was calculated by interpolating the reciprocal plasma dilution causing a granzyme B activity matching the cutoff value of the assay. Horizontal arrows mark titers exceeding the upper limit of the assay (102,400). Diamonds indicate titers significantly above the week 0 values, and asterisks indicate significant between-group differences (P < 0.05, with appropriate Bonferroni correction). Time points 2 weeks after the last applications of DNA and NYVAC/protein are highlighted by shading. (B) ADCVI activity. CEM.NKRCCR5 target cells were infected with HIV-1 DU156 or DU422 for 3 days. Plasma samples obtained at week 26 and PBMCs at an E:T ratio of 10:1 were added. After 8 days, virus amounts were measured by p24 ELISA, and the % inhibition was calculated as the proportion of p24 obtained in the presence of plasma samples versus week 0 control plasma.