Granule release (granzyme B levels) and CAF production from antiviral CD8⁺ cells. Freshly isolated CD8⁺ cells (A) from an HIV-infected patient showing strong CAF activity were left untreated (▪) or were activated with anti-CD3 IM beads (•) and were cultured as described in “Materials and methods.” (B) On day 9 or 11, CD8⁺ cells from anti-CD3 IM bead-activated cultures were washed and then treated as in panel A. At the indicated time points, samples of culture fluid were taken and frozen at -80°C. Granzyme B levels in the culture fluids were measured by ELISA (detection limit, 50 pg/mL). CAF activity in the culture fluids, indicated as the percentage suppression of HIV replication ± SD, was measured in a standardized β-chemokine—insensitive virus acute infection assay (see “Materials and methods”). Data are representative of 2 experiments, each with a different subject.