Bacterial biofilm within diseased pancreatic and biliary tracts

Abstract

Background: Bacterial community structures in human pancreatic and biliary tracts were evaluated. Methods: Gall bladder stones from 153 patients, 20 gall bladder walls, six common duct stones, 52 biliary stents, 21 duodenal biopsies, nine pancreatic duct biopsies, and five bile ducts were investigated using fluorescence in situ hybridisation (FISH) with ribosomal RNA targeted Cy3/Cy5 (carbocyanine) labelled oligonucleotide probes. Result: Duodenal, gall bladder, and bile duct walls were free of bacteria. A dense multispecies bacterial biofilm was present within the pancreatic duct of patients with calcific pancreatitis and within biliary stents, irrespective of diagnosis. The concentration, density, and amenability of the biofilm to FISH and DNA staining declined progressively with the grade of stent occlusion. The lowest detectable bacterial concentrations were found by FISH in completely occluded stents and brown/mixed gall stones. Bacteria were not detectable with FISH in cholesterol gall stones. Conclusions: A wide range of different branches and groups of bacteria participate in the development of biofilms on the surfaces of foreign bodies, such as biliary stents, mixed gall stones, or calcific pancreatic ducts, but not on the surface of pure cholesterol gall stones. Occlusion of stents leads to progressive extinction of the biofilm and mummification of its components. Deposition of cholesterol or other substances within the biofilm matrix may be a novel mechanism of host defence against bacteria present in these biofilms.

Epithelial Cells Augment Barrier Function via Activation of the Toll-Like Receptor 2/Phosphatidylinositol 3-Kinase Pathway upon Recognition of Salmonella enterica Serovar Typhimurium Curli Fibrils in the Gut

“…This is in part because of the difficulties in constructing bacterial strains deficient in lipoprotein production due to its high abundance and the deleterious effects of these mutations on bacteria. Bacteria form biofilms to provide protection from environmental insults in various niches, including the gastrointestinal tract (78)(79)(80)(81). Bacterial species express amyloid fibrils as a major component of their extracellular matrix in biofilms.…”

Microbiota, Oral Microbiome, and Pancreatic Cancer

“…These studies have reported a high number of bacteria present in the calcified pancreatic duct epithelium and in pancreatic abscess (33-37). Some of the bacteria isolated from pancreatic tissues are also known members of the oral microbiome (34, 35, 38, 39). Bacterial dissemination from the mouth to the pancreas may include the colon via bacterial translocation, general circulation, biliary duct, duodenum, and the lymphatic system (33, 40-43).…”

Plasma antibodies to oral bacteria and risk of pancreatic cancer in a large European prospective cohort study

“…Using culture methods, the microbiota isolated from the pancreas had similarities to oral microbiota, particularly in the case of pancreatitis 8–11. Bacteria reaching the pancreatic tissues by dissemination has been documented in both animal models and human subjects 9 12 13. Additionally, multiple observations have shown that oral microbiota overlap with the digestive tract microbiota, providing multiple avenues for dissemination in dysbiosis 14–17.…”