Phenotypes and HIV-1-specific T cell responses of KIR3DL1 positive CD8 cells in patients with early HIV-1 infection / 中华微生物学和免疫学杂志

ABSTRACT

Objective To investigate the phenotypes and the HIV-1-specific T cell responses of KIR3DL1 positive CD8 cells in patients with early HIV-1 infection. Methods Fifty-six HIV-1 antibody negative individuals and thirty-two patients with early HIV-1 infection were enrolled in the study. Fluores-cence-activated cell sorting (FACS) was performed to detect the phenotypes of KIR3DL1 receptor expressed on the surface of CD8 cells. The levels of IFN-γwere measured by intracellular cytokine staining assay after the PBMCs were stimulated with an HIV-1 Gag peptide pool. Results The percentages of KIR3DL1+CD8 T cells in HIV-1 negative individuals and patients with early HIV-1 infection were 1. 45% (0. 12%-8. 4%) and 0. 82% (0. 14%-6. 14%), respectively, and there was no significant difference between them. The percentages of KIR3DL1+CD8 Temra cells in HIV-1 negative individuals and patients with early HIV-1 infec-tion were (4. 55±3. 84)% and (6. 71±8. 50)%, respectively, which were significantly higher than the per-centages of KIR3DL1+CD8 Tem cells, which were (0. 50±0. 59)% and (1. 18±1. 39)%, respectively (all P<0. 01). Moreover, the percentages of KIR3DL1+CD8 Tem cells in patients with early HIV-1 infection were higher than those in HIV-1 negative individuals (P=0. 001 2). The percentage of KIR3DL1+CD8 Temra cells was positively correlated with the HIV-1 viral load in patients with early HIV-1 infection ( rs=0. 576,P=0. 000 9). The percentages of KIR3DL1+CD8 Temra cells in HIV-1 patients, whose viral loads were larger than 4. 0log, were much higher than those in HIV-1 patients with viral loads less than 4. 0 log (P=0. 002). Additionally, the levels of IFN-γsecreted by KIR3DL1 positive CD8 cells were much lesser than those secreted by KIR3DL1 negative CD8 cells (P<0. 000 1). Conclusion The receptor of KIR3DL1 was mainly expressed on CD8 Temra cells in both HIV-1 negative subjects and patients with early HIV-1 infec-tion. High HIV-1 viremia was associated with the high percentage of KIR3DL1+CD8 Temra cells. The KIR3DL1 positive CD8 cells induced lower HIV-1-specific T cell responses.