USP18 is a significant driver of memory CD4 T-cell reduced viability caused by type I IFN signaling during primary HIV-1 infection

PLoS Pathog. 2019 Oct 28;15(10):e1008060. doi: 10.1371/journal.ppat.1008060. eCollection 2019 Oct.

Abstract

The loss of Memory CD4 T-cells (Mem) is a major hallmark of HIV-1 immuno-pathogenesis and occurs early during the first months of primary infection. A lot of effort has been put into understanding the molecular mechanisms behind this loss, yet they still have not been fully identified. In this study, we unveil the unreported role of USP18 in the deleterious effects of sustained type I IFN signaling on Mem, including HIV-1-specific CD4 T-cells. We find that interfering with IFN-I signaling pathway in infected patients, notably by targeting the interferon-stimulated gene USP18, resulted in reduced PTEN expression similar to those observed in uninfected control donors. We show that AKT activation in response to cytokine treatment, T-cell receptor (TcR) triggering, as well as HIV-1 Gag stimulation was significantly improved in infected patients when PTEN or USP18 were inhibited. Finally, our data demonstrate that higher USP18 in Mem from infected patients prevent proper cell survival and long-lasting maintenance in an AKT-dependent manner. Altogether, we establish a direct role for type I IFN/USP18 signaling in the maintenance of total and virus-specific Mem and provide a new mechanism for the reduced survival of these populations during primary HIV-1 infection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Apoptosis / immunology
  • CD4-Positive T-Lymphocytes / immunology*
  • Cell Survival
  • HIV Infections / immunology
  • HIV Infections / pathology
  • HIV-1 / immunology*
  • HIV-1 / pathogenicity
  • Humans
  • Immunologic Memory / immunology*
  • Interferon Type I / immunology*
  • PTEN Phosphohydrolase / biosynthesis*
  • PTEN Phosphohydrolase / genetics
  • Proto-Oncogene Proteins c-akt / metabolism
  • Receptors, Antigen, T-Cell / immunology
  • Signal Transduction / immunology
  • Ubiquitin Thiolesterase / genetics
  • Ubiquitin Thiolesterase / metabolism*
  • gag Gene Products, Human Immunodeficiency Virus / immunology

Substances

  • Interferon Type I
  • Receptors, Antigen, T-Cell
  • gag Gene Products, Human Immunodeficiency Virus
  • Proto-Oncogene Proteins c-akt
  • PTEN Phosphohydrolase
  • PTEN protein, human
  • USP18 protein, human
  • Ubiquitin Thiolesterase

Grants and funding

This study was supported by FRQ-S (grant number: 261098 to XDL), Banting Research Foundation, and the Natural Sciences and Engineering Research Council of Canada (NSERC). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.