Bw4 motif expressed on HLA-B antigen affects HIV-1 specific T cell responses induced in patients with acute HIV-1 infection / 中华微生物学和免疫学杂志

ABSTRACT

Objective To investigate whether Bw4 motif expressed on HLA-B affects Gag-specific T cell responses in patients with acute HIV-1 infection.Methods Sequence specific primer polymerase chain reaction ( SSP-PCR) was performed for human leukocyte antigen ( HLA) typing.Peripheral blood mononuclear cells ( PBMCs) from 36 patients with six months of acute HIV-1 infection were stimulated with HIV-1 CRF01_A/E Gag peptides to detect the HIV-1 specific T cell responses by using ELISPOT assay. Results (1) The set point viral load of 18 patients carrying no Bw4 motif on HLA-B was 4.49±0.56 which was higher than that in other 18 patients carrying 1-2 Bw4 motif(s) on HLA-B (3.78±0.75) (P=0.005). (2) T cells from 26 out of 36 patients with acute HIV-1 infection responded to P24 peptides pool including 15 patients carrying no Bw4 motif on HLA-B and 11 patients carrying 1-2 Bw4 motif( s) on HLA-B, but no significant difference was observed between them (P>0.05).The magnitude of P24-specific T cell responses induced in patients carrying no Bw4 motif on HLA-B was (1317.8 ±1238.0) SFC/106 PBMCs which was greater than that induced in patients carrying 1-2 Bw4 motif(s) on HLA-B [(549.9±778.5) SFC/106 PBMCs] ( P=0.032) .The breadth of T cell responses to P24 peptides was 2(0-5) in patients carrying no Bw4 motif on HLA-B which was broader than that of patients carrying 1-2 Bw4 motif(s) on HLA-B [1(0-4)] (P=0.080).(3) The viral loads of HIV-1 infected patients carrying no Bw4 motif on HLA-B were negatively correlated with the magnitude of P24-specific T cell responses (rs=-0.482, P=0.043) and the breadth of responses to P24 peptides (rs=-0.496, P=0.036).No correlations were observed between viral loads and the magnitude or breadth of P24-specific T cell responses in HIV-1 infected patients carrying 1-2 Bw4 motif(s) on HLA-B.Conclusion Compared with HIV-1 infected patients carrying no Bw4 motif on HLA-B, the patients carrying 1-2 Bw4 motif( s) on HLA-B showed lower levels of set point viral load, weak-ened magnitude of P24-specific T cell responses and narrowed breadth of responses to P24 peptides.