5-Lipoxygenase deficiency impairs innate and adaptive immune responses during fungal infection

PLoS One. 2012;7(3):e31701. doi: 10.1371/journal.pone.0031701. Epub 2012 Mar 20.

Abstract

5-Lipoxygenase-derived products have been implicated in both the inhibition and promotion of chronic infection. Here, we sought to investigate the roles of endogenous 5-lipoxygenase products and exogenous leukotrienes during Histoplasma capsulatum infection in vivo and in vitro. 5-LO deficiency led to increased lung CFU, decreased nitric oxide production and a deficient primary immune response during active fungal infection. Moreover, H. capsulatum-infected 5-LO(-/-) mice showed an intense influx of neutrophils and an impaired ability to generate and recruit effector T cells to the lung. The fungal susceptibility of 5-LO(-/-) mice correlated with a lower rate of macrophage ingestion of IgG-H. capsulatum relative to WT macrophages. Conversely, exogenous LTB4 and LTC4 restored macrophage phagocytosis in 5-LO deficient mice. Our results demonstrate that leukotrienes are required to control chronic fungal infection by amplifying both the innate and adaptive immune response during histoplasmosis.

Publication types

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

MeSH terms

  • Animals
  • Arachidonate 5-Lipoxygenase / physiology*
  • Cell Proliferation
  • Cells, Cultured
  • Cytotoxicity, Immunologic
  • Flow Cytometry
  • Histoplasma / immunology*
  • Histoplasmosis / immunology*
  • Histoplasmosis / microbiology
  • Histoplasmosis / mortality
  • Immunity, Humoral
  • Immunity, Innate
  • Leukotriene B4 / metabolism
  • Leukotriene C4 / metabolism
  • Lung / immunology*
  • Lung / microbiology
  • Lymphocyte Activation
  • Macrophages, Peritoneal / cytology
  • Macrophages, Peritoneal / immunology*
  • Macrophages, Peritoneal / microbiology
  • Mice
  • Mice, Knockout
  • Nitric Oxide / metabolism
  • Phagocytosis
  • Survival Rate
  • T-Lymphocytes / immunology*
  • T-Lymphocytes / microbiology

Substances

  • Leukotriene B4
  • Leukotriene C4
  • Nitric Oxide
  • Arachidonate 5-Lipoxygenase