Objective: To explore the expression of CD160, a costimulator, on CD4(+) and CD8(+) T cells in chronic human immunodeficiency virus-1 (HIV-1) infected patients.
Methods: A total of 23 chronic HIV-1 infected patients were enrolled into 302 Hospital of People's Liberation Army from January 2010 to December 2011. Meanwhile, 20 healthy individuals were selected as healthy controls (HC). Peripheral blood was collected, peripheral blood mononuclear cells (PBMC) were isolated by density gradient centrifugation and CD160 was stained with fluorescent antibody. The expressions of CD160 on CD4(+) and CD8(+) T cell subsets were detected by flow cytometry and its correlation with CD4(+) T cell absolute number and HIV RNA viral load were analyzed.
Results: The expressions of CD160 on CD4(+) and CD8(+) T cell increased versus HC (on CD4(+) T cells, percentage: (14.3 ± 7.5)% vs (3.9 ± 2.2)%, median fluorescent intensity (MFI): 26.4 ± 11.0 vs 12.4 ± 2.9; on CD8(+) T cells, percentage: (40.9 ± 13.2)% vs (12.9 ± 6.6)%, MFI: 52.5 ± 17.4 vs 18.2 ± 5.0). Furthermore, the expression of CD160 on CD4(+) T cells was negatively correlated with CD4(+) T cell absolute number (r = -0.550, P = 0.010) and positively with HIV RNA load (r = 0.522, P = 0.015). However, the expression of CD160 on CD8(+) T cells was not correlated with CD4(+) T cell absolute number or HIV RNA load. The expressions of CD160 on CD8(+) T cell subsets Tn, Tcm and Tem in patients with chronic HIV-1 infection increased compared with HC (25.3 ± 17.6 vs 5.0 ± 3.1, 45.8 ± 13.0 vs 20.4 ± 4.3, 37.0 ± 13.6 vs 20.0 ± 10.8). In addition, Tn subset decreased while Tcm subset increased in CD160(+) CD8(+) T cell subset distribution in patients with HIV-1 infection compared with HC subjects.
Conclusion: CD160 may contribute to the exhaustion of CD4(+) and CD8(+) T cells and influence the distribution of memory CD8(+) T cell subsets.