Pig SISP jejunal segments: Lactobacillus plantarum and msa/srt mutant strains vs control, perfusion 4 or 8 hours

Mannose-specific interactions of Lactobacillus plantarum 299v with jejunal epithelium were investigated using an in situ pig small intestinal segment perfusion (SISP) model. L. plantarum 299v wildtype strain was compared to two isogenic mutant strains either lacking the gene encoding for the mannose-specific adhesin (msa) or sortase (srtA; responsible for anchoring of cell surface proteins like Msa to the cell wall). Salmonella typhimurium served as a positive control for gene expression analysis. Scrapings from jejunal segments were collected after perfusion with bacterial suspensions or PBS (control) for 4 or 8 hours, and host gene expression was assessed using a home-made cDNA porcine microarray. Keywords: host-microbe interaction, Lactobacillus plantarum, mannose-specific adhesion A Small Intestinal Segment Perfusion (SISP) test was performed using 4 pigs. 10 segments were prepared in the jejunum of each pig and perfused with Lactobacillus plantarum 299v wildtype, Lactobacillus plantarum 299v msa mutant strain, Lactobacillus plantarum 299v srtA mutant strain, Salmonella typhimurium or PBS (control) for 4 or 8 hours. Pooled samples from each treatment at each timepoint were used for microarray analysis. 8 comparisons were done: L. plantarum wildtype vs control (4 hours), L. plantarum wildtype vs control (8 hours), L. plantarum msa mutant vs control (4 hours), L. plantarum msa mutant vs control (8 hours), L. plantarum srt mutant vs control (4 hours), L. plantarum srt mutant vs control (8 hours), S. typhimurium vs control (8 hours), samples taken at the beginning of the experiment vs control (8 hours). Dye-swaps were performed for each comparison.