HLA-B*14:02-restricted env-specific CD8+ T-cell activity has highly potent antiviral efficacy associated with immune control of HIV infection. Journal of Virology
Immune control of HIV infection is typically associated with effective Gag-specific CD8+ T-cell responses. To investigate further the potential role of non-Gag-specific CD8+ T-cell responses in control of HIV infection, Leitman et al. focused here on HLA-B*14, where the dominant HIV-specific CD8+ T-cell response is in Env but not Gag specific.
The authors demonstrated that Env-specific HLA-B*14-restricted activity was substantially more efficacious than the subdominant HLA-B*14-restricted Gag response. Env immunodominance over Gag and strong Env-mediated selection pressure on HIV were observed only in subjects expressing HLA-B*14:02, and not HLA-B*14:01. This was reflected by an increased functional avidity of the Env response over Gag, substantially more marked for HLA-B*14:02. Finally, they showed that HLA-B*14:02 was significantly more strongly associated with viremic control than HLA-B*14:01.
In conclusion, the studies indicate that, although Gag-specific CD8+ T-cell responses may usually have greater antiviral efficacy against HIV for the several reasons described above, influences such as functional avidity of individual responses are also critically important factors that may override protein specificity in contributing to immune control of HIV infection. This finding is relevant to the development of vaccines designed to generate effective antiviral CD8+ T-cell responses.