Association between amino acid mutations in Gag protein and human leukocyte antigen class I alleles in human immunodeficiency virus-1 B' infected Han Chinese people

Abstract

To explore the human leukocyte antigen (HLA)-associated mutations in Gag protein of B' clade (human immunodeficiency virus-1) HIV-1 infected Han Chinese people and evaluate the impact of HLA associated Gag mutations on the disease progression of HIV infection. A total of 95 B' clade HIV-1 infected Han Chinese cases were recruited. The gag sequences were amplified from viral RNA and sequenced directly. HLA-I genotypes were detected with the assay of polymerase chain reaction-sequence specific primer (PCR-SSP). HLA-associated mutations were identified and the relationships between HLA-associated mutations and CD4+ T cell counts or plasma viral loads analyzed. Forty-seven kinds of mutations at 28 sites (15, 18, 26, 30, 34, 46, 62, 67, 81, 84, 90, 102, 118, 121, 122, 125, 146, 147, 173, 176, 252, 357, 374, 376, 437, 470, 471, 478) of Gag protein were significantly associated with particular HLA class I allelotypes (P < 0.05). Among which, 9 sites (26, 30, 81, 84, 125, 146, 147, 357, 437) were located within 13 known cytotoxic T-lymphocyte (CTL) epitopes or flanking regions. The number of HLA-associated mutations was significantly associated with both CD4 T cell counts (r = -0.318, P = 0.002) and viral loads (r = 0.360, P = 0.003). HLA-associated mutations may have a significant impact on HIV disease progression in B' clade HIV-1 infected Han Chinese population.