Trans-10, cis-12 conjugated linoleic acid modulates phagocytic responses of canine peripheral blood polymorphonuclear neutrophilic leukocytes exposed to Clostridium difficile toxin B

Vet Immunol Immunopathol. 2009 Aug 15;130(3-4):178-86. doi: 10.1016/j.vetimm.2009.02.005. Epub 2009 Feb 13.

Abstract

Trans-10, cis-12 conjugated linoleic acid (t10c12-CLA) has been reported to enhance phagocyte function. Clostridium difficile toxin B (TcdB) has been known to inhibit Ras-homologous (Rho) guanosine triphosphatases (GTPases) which play essential roles in neutrophil immune functions. Here, we examined whether in vitro treatment with t10c12-CLA modulates the filamentous actin (F-actin) polymerization, phagocytic capacity, and oxidative burst activity (OBA) of canine peripheral blood polymorphonuclear neutrophilic leukocytes (PMNs) exposed to TcdB. Treatment with t10c12-CLA, but not linoleic acid, enhanced PMN F-actin polymerization, phagocytic capacity, and OBA, while TcdB suppressed these functions. t10c12-CLA reversed the suppressive effects of TcdB on these PMN functions. t10c12-CLA stimulated F-actin polymerization regardless of whether phagocytosis was stimulated by microspheres but only elevated OBA when microspheres were added. We asked whether the effects of t10c12-CLA were associated with changes in the activation of the Rho GTPase Cdc42. Treatment with t10c12-CLA augmented Cdc42 activity in both TcdB-treated and TcdB-naive PMNs during phagocytosis. Thus, t10c12-CLA up-regulates PMN phagocytic responses attenuated by TcdB. This effect is associated with an increase in actin polymerization and may involve the activation of Cdc42.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actins / metabolism
  • Animals
  • Bacterial Proteins / toxicity*
  • Bacterial Toxins / toxicity*
  • Base Sequence
  • Clostridioides difficile / immunology
  • Clostridioides difficile / pathogenicity
  • DNA Primers / genetics
  • Dogs / immunology*
  • Immunity, Innate / drug effects
  • In Vitro Techniques
  • Linoleic Acids, Conjugated / pharmacology*
  • Neutrophils / drug effects*
  • Neutrophils / immunology*
  • Neutrophils / metabolism
  • Phagocytosis / drug effects*
  • Respiratory Burst / drug effects
  • Up-Regulation / drug effects
  • cdc42 GTP-Binding Protein / genetics
  • cdc42 GTP-Binding Protein / metabolism
  • rho GTP-Binding Proteins / antagonists & inhibitors
  • rho GTP-Binding Proteins / immunology

Substances

  • Actins
  • Bacterial Proteins
  • Bacterial Toxins
  • DNA Primers
  • Linoleic Acids, Conjugated
  • toxB protein, Clostridium difficile
  • trans-10,cis-12-conjugated linoleic acid
  • cdc42 GTP-Binding Protein
  • rho GTP-Binding Proteins