How to cite this article: Vet. Res. (2009) 40:64
DOI: 10.1051/vetres/2009045

The mycotoxin deoxynivalenol promotes uptake of Salmonella Typhimurium in porcine macrophages, associated with ERK1/2 induced cytoskeleton reorganization

Virginie Vandenbroucke¹, Siska Croubels¹, Elin Verbrugghe², Filip Boyen², Patrick De Backer¹, Richard Ducatelle², Ivan Rychlik³, Freddy Haesebrouck² and Frank Pasmans<sup>2

1</sup>  Department of Pharmacology, Toxicology and Biochemistry, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium
²  Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium
³  Department of Bacteriology, Laboratory of Salmonella infections, Veterinary Research Institute, Hudcova 70, 612 00 Brno, Czech Republik

Received 15 January 2009; accepted 11 August 2009; published online 13 August 2009

Abstract - Both the mycotoxin deoxynivalenol (DON) and Salmonella Typhimurium are major issues in swine production. This study aimed at examining the interaction between DON and Salmonella Typhimurium at the level of the porcine innate immune system, represented by macrophages. First, we assessed the direct cytotoxic effect of DON on porcine macrophages. Incubation with 0.25 g/mL of DON or higher resulted in a significant cytotoxic effect after 24 h of incubation. Secondly, the direct toxic effect ofDONon the growth and on the expression of Salmonella pathogenicity island 1 (SPI-1) and SPI-2 virulence genes of Salmonella Typhimurium was determined. At low non-cytotoxic concentrations, as can be found in the serum of pigs, DON did not have any effect on either growth or virulence gene expression of Salmonella Typhimurium. However, when the invasion and intracellular survival of Salmonella Typhimurium in macrophages preexposed to 0.025 g/mL of DON was examined, DON significantly promoted the uptake of Salmonella Typhimurium into macrophages. The enhanced uptake coincided with marked F-actin reorganization of the cells, which was due to the activation of extracellular signal-regulated protein kinase 1/2 (ERK1/2). These results suggest that low but relevant concentrations of DON modulate the innate immune system and could thus increase the susceptibility of pigs to infections with Salmonella Typhimurium.

Key words: deoxynivalenol / Salmonella Typhimurium / pig / macrophage / cytoskeleton

Corresponding author: virginie.vandenbroucke@ugent.be

© INRA, EDP Sciences 2009