Negative Immune Regulator Tim-3 Is Overexpressed on T Cells in Hepatitis C Virus Infection and Its Blockade Rescues Dysfunctional CD4+ and CD8+ T Cells

L Golden-Mason, BE Palmer, N Kassam… - Journal of …, 2009 - Am Soc Microbiol
L Golden-Mason, BE Palmer, N Kassam, L Townshend-Bulson, S Livingston, BJ McMahon…
Journal of virology, 2009Am Soc Microbiol
ABSTRACT A number of emerging molecules and pathways have been implicated in
mediating the T-cell exhaustion characteristic of chronic viral infection. Not all dysfunctional
T cells express PD-1, nor are they all rescued by blockade of the PD-1/PD-1 ligand pathway.
In this study, we characterize the expression of T-cell immunoglobulin and mucin domain-
containing protein 3 (Tim-3) in chronic hepatitis C infection. For the first time, we found that
Tim-3 expression is increased on CD4+ and CD8+ T cells in chronic hepatitis C virus (HCV) …
Abstract
A number of emerging molecules and pathways have been implicated in mediating the T-cell exhaustion characteristic of chronic viral infection. Not all dysfunctional T cells express PD-1, nor are they all rescued by blockade of the PD-1/PD-1 ligand pathway. In this study, we characterize the expression of T-cell immunoglobulin and mucin domain-containing protein 3 (Tim-3) in chronic hepatitis C infection. For the first time, we found that Tim-3 expression is increased on CD4+ and CD8+ T cells in chronic hepatitis C virus (HCV) infection. The proportion of dually PD-1/Tim-3-expressing cells is greatest in liver-resident T cells, significantly more so in HCV-specific than in cytomegalovirus-specific cytotoxic T lymphocytes. Tim-3 expression correlates with a dysfunctional and senescent phenotype (CD127low CD57high), a central rather than effector memory profile (CD45RAnegative CCR7high), and reduced Th1/Tc1 cytokine production. We also demonstrate the ability to enhance T-cell proliferation and gamma interferon production in response to HCV-specific antigens by blocking the Tim-3-Tim-3 ligand interaction. These findings have implications for the development of novel immunotherapeutic approaches to this common viral infection.
American Society for Microbiology