Tim-3 negatively mediates natural killer cell function in LPS-induced endotoxic shock

PLoS One. 2014 Oct 22;9(10):e110585. doi: 10.1371/journal.pone.0110585. eCollection 2014.

Abstract

Sepsis is an exaggerated inflammatory condition response to different microorganisms with high mortality rates and extremely poor prognosis. Natural killer (NK) cells have been reported to be the major producers of IFN-γ and key players in promoting systematic inflammation in lipopolysaccharide (LPS)-induced endotoxic shock. T-cell immunoglobulin and mucin domain (Tim)-3 pathway has been demonstrated to play an important role in the process of sepsis, however, the effect of Tim-3 on NK cell function remains largely unknown. In this study, we observed a dynamic inverse correlation between Tim-3 expression and IFN-γ production in NK cells from LPS-induced septic mice. Blockade of the Tim-3 pathway could increase IFN-γ production and decrease apoptosis of NK cells in vitro, but had no effect on the expression of CD107a. Furthermore, NK cell cytotoxicity against K562 target cells was enhanced after blocking Tim-3 pathway. In conclusion, our results suggest that Tim-3 pathway plays an inhibitory role in NK cell function, which might be a potential target in modulating the excessive inflammatory response of LPS-induced endotoxic shock.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Apoptosis
  • Cytotoxicity, Immunologic
  • Gene Expression
  • Hepatitis A Virus Cellular Receptor 2
  • Humans
  • Interferon-gamma / metabolism
  • K562 Cells
  • Killer Cells, Natural / immunology
  • Killer Cells, Natural / metabolism
  • Lipopolysaccharides / pharmacology*
  • Male
  • Mice, Inbred BALB C
  • Receptors, Virus / physiology*
  • Shock, Septic / immunology*
  • Shock, Septic / metabolism
  • Signal Transduction

Substances

  • Havcr2 protein, mouse
  • Hepatitis A Virus Cellular Receptor 2
  • Lipopolysaccharides
  • Receptors, Virus
  • Interferon-gamma

Grants and funding

This work was supported by the Infectious Diseases Control Project from Ministry of Health of China (2012zx10004-207). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.