Porcine stomachs with and without gastric ulcer differ in Lactobacillus load and strain characteristics.

Although Lactobacillus species are recognized as normal inhabitants of porcine gastric mucosa, the association of these bacteria with health status or gastric ulcer disease has never been considered. We investigated the bacterial load of Lactobacillus isolated from the antrum, corpus, and pars esophagea of stomachs with (n = 13) and without (n = 10) ulcer of the pars esophagea of slaughtered pigs. We also evaluated in vitro antagonistic properties against typical pathogens of strains isolated from stomachs without ulcer. To quantify Lactobacillus, gastric mucosa samples obtained with 5 mm biopsy punches were smeared on MRS agar and colonies were counted after 48 h of incubation under anaerobic conditions. The score of Lactobacillus was significantly greater in the antrum and corpus of stomachs without ulcer (P < 0.001 for both) when compared with stomachs with ulcer. Fingerprint profiles, obtained by repetitive sequence-based PCR using (GTG)5 primers, showed that the isolates were highly diverse. The reduction of Lactobacillus load in porcine stomachs may be a contributing factor for gastric ulcer. Strains isolated from healthy stomachs, which showed a wide spectrum of antagonistic activity against pathogens, may be viewed as an untapped source of bacteria with potential beneficial properties that deserve to be further investigated.

Toll-like receptor (TLR2, TLR4 and TLR5) gene polymorphisms and Helicobacter pylori infection in children with and without duodenal ulcer.

Helicobacter pylori infection is mainly acquired in childhood, and polymorphisms in the host genes coding for Toll-like receptors (TLRs) may influence the innate and adaptive immune response to the infection, affecting the susceptibility to H. pylori or the disease outcomes. Our aim was to investigate whether TLR4, TLR2, and TLR5 polymorphisms were associated with H. pylori susceptibility and risk for duodenal ulcer in children. Gastric biopsy specimens were obtained at endoscopy for evaluation of H. pylori status, TLR4, TLR2 and TLR5 polymorphisms from 486 children (254 H. pylori-negative and 232 H. pylori-positive: 72 with and 160 without duodenal ulcer). cagA status of H. pylori infection was investigated by PCR. The levels of gastric cytokines were detected by ELISA. H. pylori-positivity or duodenal ulcer were not associated with TLR2, TLR4 or TLR5 polymorphisms. Otherwise, the presence of TLR4 polymorphic allele was associated with infection by cagA-positive strains and with increased gastric levels of interleukin-8 and interleukin-10. TLR4 polymorphism might ultimately contribute to more severe consequences of the infection in adulthood since it was associated with susceptibility to cagA-positive H. pylori infection early in life.