Intestinally secreted C-type lectin Reg3b attenuates salmonellosis but not listeriosis in mice

The Reg3 protein family, including the human member designated pancreatitis-associated protein (PAP), consists of secreted proteins that contain a C-type lectin domain involved in carbohydrate binding. They are expressed by intestinal epithelial cells. Colonization of germ-free mice and intestinal infection with pathogens increase the expression of Reg3g and Reg3b in the murine ileum. Reg3g is directly bactericidal for Gram-positive bacteria, but the exact role of Reg3b in bacterial infections is unknown. To investigate the possible protective role of Reg3b in intestinal infection, Reg3b knockout (Reg3b-/-) mice and wild-type (WT) mice were orally infected with Gram-negative Salmonella enteritidis or Gram-positive Listeria monocytogenes. At day 2 after oral Listeria infection and at day 4 after oral Salmonella infection, mice were sacrificed to collect intestinal and other tissues for pathogen quantification. Protein expression of Reg3b and Reg3g was determined in intestinal mucosal scrapings of infected and noninfected mice. In addition, ex vivo binding of ileal mucosal Reg3b to Listeria and Salmonella was investigated. Whereas recovery of Salmonella or Listeria from feces of Reg3b-/- mice did not differ from that from feces of WT mice, significantly higher numbers of viable Salmonella, but not Listeria, bacteria were recovered from the colon, mesenteric lymph nodes, spleen, and liver of the Reg3b-/- mice than from those of WT mice. Mucosal Reg3b binds to both bacterial pathogens and may interfere with their mode of action. Reg3b plays a protective role against intestinal translocation of the Gram-negative bacterium S. enteritidis in mice but not against the Gram-positive bacterium L. monocytogenes

Transcription profiling of rat colonic mucosa at different time points following Salmonella infection

Salmonella enteritidis is suggested to translocate in the small intestine. Previously we identified that prebiotics, fermented in the colon, increased Salmonella translocation in rats, suggesting involvement of the colon in translocation. Effects of Salmonella on colonic gene expression in vivo are largely unknown. The aim of this study was to characterize time dependent Salmonella induced changes of colonic mucosal gene expression in rats using whole genome microarrays. Rats were orally infected with Salmonella enteritidis to mimic a foodbore infection and colonic gene expression was determined at day 1, 3 and 6 post-infection (n=8 per timepoint). Agilent rat whole genome microarray (G4131A Agilent Technologies) were used. Results indicate that colon is clearly a target tissue for Salmonella considering the abundant changes in mucosal gene expression observed

Transcription profiling of rat colonic mucosa at different time points following Salmonella infection

Salmonella enteritidis is suggested to translocate in the small intestine. Previously we identified that prebiotics, fermented in the colon, increased Salmonella translocation in rats, suggesting involvement of the colon in translocation. Effects of Salmonella on colonic gene expression in vivo are largely unknown. The aim of this study was to characterize time dependent Salmonella induced changes of colonic mucosal gene expression in rats using whole genome microarrays. Rats were orally infected with Salmonella enteritidis to mimic a foodbore infection and colonic gene expression was determined at day 1, 3 and 6 post-infection (n=8 per timepoint). Agilent rat whole genome microarray (G4131A Agilent Technologies) were used. Results indicate that colon is clearly a target tissue for Salmonella considering the abundant changes in mucosal gene expression observed

Colonic gene expression upon dietary treatment

To increase our knowledge of the effects of Fructo oligosaccharides (FOS) on the intestinal barrier function in rats, a controlled rat infection study was performed. Two groups of rats were adapted to a diet with or without FOS. mRNA was collected from the mucosa of the colon and changes in gene expression were assessed using an agilent rat whole genome microarray (G4131A Agilent Technologies). Results indicate that dietary FOS influences energy metabolism, which will most likely play a role in the effects of FOS on the intestinal barrier

Colonic gene expression upon dietary treatment

To increase our knowledge of the effects of Fructo oligosaccharides (FOS) on the intestinal barrier function in rats, a controlled rat infection study was performed. Two groups of rats were adapted to a diet with or without FOS. mRNA was collected from the mucosa of the colon and changes in gene expression were assessed using an agilent rat whole genome microarray (G4131A Agilent Technologies). Results indicate that dietary FOS influences energy metabolism, which will most likely play a role in the effects of FOS on the intestinal barrier

Colonic gene expression upon Salmonella infection and dietary treatment

To increase our knowledge of the effects of Fructo oligosaccharides (FOS) on Salmonella infection in fats, a controlle rat infection study was performed. Two groups of 12 rats were adapted for 14 days to a cellulose diet and one group of 12 rats to a FOS diet. One cellulose-fed group and the FOS-fed group were infected with Salmonella. Two days post infection mRNA was collected from the mucosa of the colon and changes in gene expression were assessed using an Agilent rat whole genome microarray (G4131A Agilent Technologies). Results indicate that Salmonella affects colonic mucosal gene expression, which is further enhanded by dietary FOS