Differential clade-specific HLA-B* 3501 association with HIV-1 disease outcome is linked to immunogenicity of a single Gag epitope

PC Matthews, M Koyanagi, HN Kløverpris… - Journal of …, 2012 - Am Soc Microbiol
PC Matthews, M Koyanagi, HN Kløverpris, M Harndahl, A Stryhn, T Akahoshi, H Gatanaga…
Journal of virology, 2012Am Soc Microbiol
The strongest genetic influence on immune control in HIV-1 infection is the HLA class I
genotype. Rapid disease progression in B-clade infection has been linked to HLA-B* 35
expression, in particular to the less common HLA-B* 3502 and HLA-B* 3503 subtypes but
also to the most prevalent subtype, HLA-B* 3501. In these studies we first demonstrated that
whereas HLA-B* 3501 is associated with a high viral set point in two further B-clade-infected
cohorts, in Japan and Mexico, this association does not hold in two large C-clade-infected …
Abstract
The strongest genetic influence on immune control in HIV-1 infection is the HLA class I genotype. Rapid disease progression in B-clade infection has been linked to HLA-B*35 expression, in particular to the less common HLA-B*3502 and HLA-B*3503 subtypes but also to the most prevalent subtype, HLA-B*3501. In these studies we first demonstrated that whereas HLA-B*3501 is associated with a high viral set point in two further B-clade-infected cohorts, in Japan and Mexico, this association does not hold in two large C-clade-infected African cohorts. We tested the hypothesis that clade-specific differences in HLA associations with disease outcomes may be related to distinct targeting of critical CD8+ T-cell epitopes. We observed that only one epitope was significantly targeted differentially, namely, the Gag-specific epitope NPPIPVGDIY (NY10, Gag positions 253 to 262) (P = 2 × 10−5). In common with two other HLA-B*3501-restricted epitopes, in Gag and Nef, that were not targeted differentially, a response toward NY10 was associated with a significantly lower viral set point. Nonimmunogenicity of NY10 in B-clade-infected subjects derives from the Gag-D260E polymorphism present in ∼90% of B-clade sequences, which critically reduces recognition of the Gag NY10 epitope. These data suggest that in spite of any inherent HLA-linked T-cell receptor repertoire differences that may exist, maximizing the breadth of the Gag-specific CD8+ T-cell response, by the addition of even a single epitope, may be of overriding importance in achieving immune control of HIV infection. This distinction is of direct relevance to development of vaccines designed to optimize the anti-HIV CD8+ T-cell response in all individuals, irrespective of HLA type.
American Society for Microbiology