In:
Frontiers in Immunology, Frontiers Media SA, Vol. 12 ( 2021-6-10)
Abstract:
Targeting immune checkpoints for HIV treatment potentially provides a double benefit resulting from the ability to restore viral-specific CD8 + T-cell functions and enhance HIV production from reservoir cells. Despite promising pre-clinical data, PD-1 blockade alone in HIV-1-infected patients with advanced cancer has shown limited benefits in controlling HIV, suggesting the need for additional targets beyond PD-1. CD39 and PD-1 are highly co-expressed on CD8 + T cells in HIV-1 infection. However, the characteristics of CD39 and PD-1 dual-positive CD8 + T-cell subsets in chronic HIV-1 infection remain poorly understood. Methods This study enrolled 72 HIV-1-infected patients, including 40 treatment naïve and 32 ART patients. A total of 11 healthy individuals were included as controls. Different subsets of CD8 + T cells defined by CD39 and/or PD-1 expression were studied by flow cytometry. The relationships between the frequencies of the different subsets and parameters indicating HIV-1 disease progression were analyzed. Functional (i.e., cytokine secretion, viral inhibition) assays were performed to evaluate the impact of the blockade of adenosine and/or PD-1 signaling on CD8 + T cells. Results The proportions of PD-1 + , CD39 + , and PD-1 + CD39 + CD8 + T cells were significantly increased in treatment naïve patients but were partially lowered in patients on antiretroviral therapy. In treatment naïve patients, the proportions of PD-1 + CD39 + CD8 + T cells were negatively correlated with CD4 + T-cell counts and the CD4/CD8 ratio, and were positively correlated with viral load. CD39 + CD8 + T cells expressed high levels of the A2A adenosine receptor and were more sensitive to 2-chloroadenosine-mediated functional inhibition than their CD39 - counterparts. In vitro , a combination of blocking CD39/adenosine and PD-1 signaling showed a synergic effect in restoring CD8 + T-cell function, as evidenced by enhanced abilities to secrete functional cytokines and to kill autologous reservoir cells. Conclusion In patients with chronic HIV-1 infection there are increased frequencies of PD-1 + , CD39 + , and PD-1 + CD39 + CD8 + T cells. In treatment naïve patients, the frequencies of PD-1 + CD39 + CD8 + T cells are negatively correlated with CD4 + T-cell counts and the CD4/CD8 ratio and positively correlated with viral load. Combined blockade of CD39/adenosine and PD-1 signaling in vitro may exert a synergistic effect in restoring CD8 + T-cell function in HIV-1-infected patients.
Type of Medium:
Online Resource
ISSN:
1664-3224
DOI:
10.3389/fimmu.2021.687296
DOI:
10.3389/fimmu.2021.687296.s001
Language:
Unknown
Publisher:
Frontiers Media SA
Publication Date:
2021
detail.hit.zdb_id:
2606827-8
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