The role of LAT in increased CD8+ T cell exhaustion in trigeminal ganglia of mice latently infected with herpes simplex virus 1

J Virol. 2011 May;85(9):4184-97. doi: 10.1128/JVI.02290-10. Epub 2011 Feb 9.

Abstract

Herpes simplex virus (HSV) infection is a classic example of latent viral infection in humans and experimental animal models. The HSV-1 latency-associated transcript (LAT) plays a major role in the HSV-1 latency reactivation cycle and thus in recurrent disease. Whether the presence of LAT leads to generation of dysfunctional T cell responses in the trigeminal ganglia (TG) of latently infected mice is not known. To address this issue, we used LAT-positive [LAT(+)] and LAT-deficient [LAT(-)] viruses to evaluate the effect of LAT on CD8 T cell exhaustion in TG of latently infected mice. The amount of latency as determined by quantitative reverse transcription-PCR (qRT-PCR) of viral DNA in total TG extracts was 3-fold higher with LAT(+) than with LAT(-) virus. LAT expression and increased latency correlated with increased mRNA levels of CD8, PD-1, and Tim-3. PD-1 is both a marker for exhaustion and a primary factor leading to exhaustion, and Tim-3 can also contribute to exhaustion. These results suggested that LAT(+) TG contain both more CD8(+) T cells and more CD8(+) T cells expressing the exhaustion markers PD-1 and Tim-3. This was confirmed by flow cytometry analyses of expression of CD3/CD8/PD-1/Tim-3, HSV-1, CD8(+) T cell pentamer (specific for a peptide derived from residues 498 to 505 of glycoprotein B [gB(498-505)]), interleukin-2 (IL-2), and tumor necrosis factor alpha (TNF-α). The functional significance of PD-1 and its ligands in HSV-1 latency was demonstrated by the significantly reduced amount of HSV-1 latency in PD-1- and PD-L1-deficient mice. Together, these results may suggest that both PD-1 and Tim-3 are mediators of CD8(+) T cell exhaustion and latency in HSV-1 infection.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Antigens, Differentiation / biosynthesis
  • CD8 Antigens / biosynthesis
  • CD8-Positive T-Lymphocytes / immunology*
  • Flow Cytometry
  • Gene Expression Profiling
  • Hepatitis A Virus Cellular Receptor 2
  • Herpes Simplex / immunology*
  • Herpes Simplex / virology
  • Herpesvirus 1, Human / immunology*
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C57BL
  • MicroRNAs / metabolism*
  • Programmed Cell Death 1 Receptor
  • Receptors, Virus / biosynthesis
  • Trigeminal Ganglion / immunology*
  • Virus Latency*

Substances

  • Antigens, Differentiation
  • CD8 Antigens
  • Havcr2 protein, mouse
  • Hepatitis A Virus Cellular Receptor 2
  • MicroRNAs
  • Pdcd1 protein, mouse
  • Programmed Cell Death 1 Receptor
  • Receptors, Virus
  • latency associated transcript, herpes simplex virus-1