Differential Potency and Breadth of the Same Epitope-Specific CTLs to Inhibit HIV-1 Replication based on TCR Usage

Abstract

Increasing evidence suggests that the immune control of viral replication by HIV-1-specific cytotoxic T lymphocytes (CTLs) is relevant to the selection of human leukocyte antigen (HLA) allele-restricted antigen-specific CTL repertoire. But the underlying factors accounting for CTL functional difference from T cell receptor (TCR) clonal diversity are currently unclear. Here we found that CTL repertoire specific for HLA-B*27-restricted HIV-1 Gag p24 epitope KK10 (KRWIILGLNK, residues 263-272) selected multiple TCR clonotypes. By dissection of the bulk KK10-specific CTL compartment, differential potency and breadth of KK10-specific CTL clones to inhibit HIV-1 replication was defined due to the distinct TCR usage. Superior control of viral replication of wild-type HIV-1 isolates was observed by the TCR-clonotypic CTLs characteristic of higher ability to produce MIP-1β. A unique TCR-equipped KK10- specific CTLs efficiently controlled wide-type HIV-1 isolates and broadly cross-recognized viral variants. These data suggest that clonally diverse CTL responses to a viral epitope increase the likelihood that multiple divergent strains of viruses may be recognized by cross-reactive CTLs through immunization with only a single viral epitope sequence.