FIG. 1.

HIV-specific CD8 T cells can potently suppress replication of primary HIV isolates in autologous CD4 cells. (A) Bulk CD8 T cells expanded in vitro from an elite controller (subject 013196g) by stimulation of PBMCs with CD3:CD4-bispecific monoclonal antibody inhibit HIV R5 replication in autologous CD4 T cells at the indicated effector/target cell ratios. The control of uninfected CD4 T cells showed that there were no autologous viruses grown out from the tested subject during the period of the assay. (B) Bulk CD8 T cells directly isolated from peripheral blood of the same subject by positive selection with anti-CD8 antibody-coated magnetic beads suppressed HIV X4 replication in autologous CD4 T cells at a 1:1 ratio of CD8 to CD4 T cells. (C) The Gag epitope KK10-specific, HLA-B*27-restricted CD8 T-cell clone recognized pNL4-3 wild-type virus but did not recognize an engineered escape variant which contains R-to-K and L-to-M mutations within the KK10 epitope and thus abrogates HLA class I binding with the peptide. (D) The B*57-restricted cell line specific for the epitope IW9 in Gag inhibited the R5 and CRF_01 viruses over time, whereas it had no demonstrable effect on HIV SE virus, which contains a single-amino-acid substitution, A-to-P, known to alter the peptide processing.