CCR5 controls immune and metabolic functions during Toxoplasma gondii infection

PLoS One. 2014 Aug 13;9(8):e104736. doi: 10.1371/journal.pone.0104736. eCollection 2014.

Abstract

CCR5, an important receptor related to cell recruitment and inflammation, is expressed during experimental Toxoplasma gondii infection. However, its role in the immunopathology of toxoplasmosis is not clearly defined yet. Thus, we inoculated WT and CCR5(-/-) mice with a sub lethal dose of the parasite by oral route. CCR5(-/-) mice were extremely susceptible to infection, presenting higher parasite load and lower tissue expression of IL-12p40, IFN-γ, TNF, IL-6, iNOS, Foxp3, T-bet, GATA-3 and PPARα. Although both groups presented inflammation in the liver with prominent neutrophil infiltration, CCR5(-/-) mice had extensive tissue damage with hepatocyte vacuolization, steatosis, elevated serum triglycerides and transaminases. PPARα agonist Gemfibrozil improved the vacuolization but did not rescue CCR5(-/-) infected mice from high serum triglycerides levels and enhanced mortality. We also found intense inflammation in the ileum of CCR5(-/-) infected mice, with epithelial ulceration, augmented CD4 and decreased frequency of NK cells in the gut lamina propria. Most interestingly, these findings were accompanied by an outstanding accumulation of neutrophils in the ileum, which seemed to be involved in the gut immunopathology, once the depletion of these cells was accompanied by reduced local damage. Altogether, these data demonstrated that CCR5 is essential to the control of T. gondii infection and to maintain the metabolic, hepatic and intestinal integrity. These findings add novel information on the disease pathogenesis and may be relevant for directing future approaches to the treatment of multi-deregulated diseases.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Analysis of Variance
  • Animals
  • Cytokines / metabolism
  • DNA Primers / genetics
  • Female
  • Flow Cytometry
  • Gemfibrozil
  • Gene Knockout Techniques
  • Ileum / immunology
  • Ileum / pathology
  • Immunohistochemistry
  • Kaplan-Meier Estimate
  • Mice
  • Mice, Knockout
  • Neutrophils / immunology
  • Real-Time Polymerase Chain Reaction
  • Receptors, CCR5 / genetics*
  • Receptors, CCR5 / immunology*
  • Statistics, Nonparametric
  • Toxoplasmosis / immunology*
  • Toxoplasmosis / metabolism*
  • Triglycerides / blood

Substances

  • CCR5 protein, mouse
  • Cytokines
  • DNA Primers
  • Receptors, CCR5
  • Triglycerides
  • Gemfibrozil

Grants and funding

The research leading to these results received support and funding from the São Paulo Research Foundation (FAPESP) under grant agreements no. 2012/14524-9 (Thematic Project), 2013/08216-2 (Center for Research in Inflammatory Disease), from the University of São Paulo NAP-DIN under grant agreement n° 11.1.21625.01.0. and from Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.