FIG 3

Env-rFc immunization elicits ADCC responses. A fluorescence-based ADCC-GTL assay was used to detect ADCC activity in the sera of Env-rFc- or Env-immunized animals. CEM.NKR_CCR5 target cells were coated with HIV_BaL gp120, which was the immunogen used to immunize animals. Effector cell-derived granzyme B (GzB) is delivered into target cells as a result of antigen-specific antibody-FcγR interactions. Shown here is the percentage of target cells with GzB activity as a result of GzB hydrolysis of a fluorogenic peptide substrate. The cutoff for positivity for GzB activity is 8%. The P value was calculated using the Mann-Whitney test.