CXCR4 blockade decreases CD4+ T cell exhaustion and improves survival in a murine model of polymicrobial sepsis

PLoS One. 2017 Dec 12;12(12):e0188882. doi: 10.1371/journal.pone.0188882. eCollection 2017.

Abstract

Sepsis is a dysregulated systemic response to infection involving many inflammatory pathways and the induction of counter-regulatory anti-inflammatory processes that results in a state of immune incompetence and can lead to multi-organ failure. CXCR4 is a chemokine receptor that, following ligation by CXCL12, directs cells to bone marrow niches and also plays an important role in T cell cosignaling and formation of the immunological synapse. Here, we investigated the expression and function of CXCR4 in a murine model of polymicrobial sepsis. Results indicate that CXCR4 is selectively upregulated on naïve CD4+ and CD8+ T cells and CD4+ central memory T cells following the induction of sepsis, and that CXCR4 antagonism resulted in a significant decrease in sepsis-induced mortality. We probed the mechanistic basis for these findings and found that CXCR4 antagonism significantly increased the number of peripheral CD4+ and CD8+ T cells following sepsis. Moreover, mice treated with the CXCR4 antagonist contained fewer PD-1+ LAG-3+ 2B4+ cells, suggesting that blockade of CXCR4 mitigates CD4+ T cell exhaustion during sepsis. Taken together, these results characterize CXCR4 as an important pathway that modulates immune dysfunction and mortality following sepsis, which may hold promise as a target for future therapeutic intervention in septic patients.

MeSH terms

  • Animals
  • CD4-Positive T-Lymphocytes / immunology*
  • CD8-Positive T-Lymphocytes / immunology
  • Disease Models, Animal*
  • Female
  • Flow Cytometry
  • Immunologic Memory
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Receptors, CXCR4 / antagonists & inhibitors*
  • Sepsis / immunology*
  • Sepsis / microbiology
  • Survival Analysis

Substances

  • CXCR4 protein, mouse
  • Receptors, CXCR4