Upregulation of PD-L1 on monocytes and dendritic cells by HIV-1 derived TLR ligands.

Partners AIDS Research Center, Massachusetts General Hospital, Division of AIDS, Harvard Medical School, Boston, Massachusetts, USA.
AIDS (London, England) (Impact Factor: 6.56). 04/2008; 22(5):655-8. DOI: 10.1097/QAD.0b013e3282f4de23
Source: PubMed

ABSTRACT Increased PD-L1 expression has been reported in HIV-1-infected individuals, but the mechanisms leading to PD-L1 upregulation remain to be elucidated. Here we demonstrate that HIV-1-derived Toll-like receptor (TLR)7/8 ligands can induce MyD88-dependent upregulation of PD-L1 on plasmacytoid dendritic cells, myeloidic dendritic cells and monocytes. These data suggest a mechanism through which HIV-1-derived TLR ligands might contribute to the functional impairment of virus-specific PD-1-positive T cells by inducing the upregulation of PD-L1 on antigen-presenting cells.

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