Journal of Bacteriology & Parasitology

Host Helicobacter interactions in the mucus niche

3^rd International Congress on Bacteriology and Infectious Diseases

August 04-06, 2015 Valencia, Spain

Sara K Linden1, Chunsheng Jin1, Barbara Adamczyk1, Bram Flahou2, Ellen De Bruyne2, Annemieke Smet2, Freddy Haesebrouck2, Niclas GKarlsson1 and Medea Padra1

Posters-Accepted Abstracts: J Bacteriol Parasitol

Abstract:

Helicobacter pylori chronically infect half of the world’s human population and is the main etiological agent causing gastric
ulcers and cancer. Gastric cancer is globally the second most prevalent cause of death due to malignancy. Helicobacter
suiscolonizes the gastric mucosa and in pigs it is associated with gastritis, decreased daily weight gain and possibly gastric
ulcer disease. Helicobactersuisis also the most prevalent non-Helicobacter pylori Helicobacter species in the human stomach
(6%) and is associated with peptic ulcer disease, gastric mucosa-associated lymphoid tissue lymphoma and chronic gastritis.
Helicobacters are prone to developing antibiotic resistance and recurrence frequently occurs. H. pylori-infected rhesus monkeys
and human children secreting mucins with less H. pylori binding capacity develop higher H. pylori density infections and
gastritis supporting that the ability of secreted mucins to bind to H. pylori protects the gastric epithelium. Gastric mucin
turnover is impaired during H. pylori infection which in turn creates a more stable environment for H. pylori to colonize long
term.H. pylori and H. suis bound to human and pig mucins via the mucinglycans, albeit with distinctly different specificites: The
most notable difference being that, H. suis bound to neutral glycans with an acidic pH optimum. This unusual binding mode
may be the reason for that H. suis in addition to colonizing the mucus layer also colonizes the acid producing parietal cells. We
found over 300 glycan structures on mucins from 16 humansand each individual carried 60-120 structures whereas we found
around 250 structures in four pigs. Mucinsdifferently regulate Helicobacter proliferation, gene expression and downstream
interactions with host cells. This regulation appeared to occur via at least three glycan response pathways. Both in primate
and pig models of infection, host glycosylation were altered during infection which affected the ability of these pathogens
to interact with their hosts and the outcome of the interaction. In conclusion, when aHelicobacteren counter the mucins that
builds up the mucus layer its behavior changes in a host specific manner in response to the mucinglycans. This “changed”
pathogen then interacts with the host epithelial cells which respond by changing its mucins and mucinglycans which in turn
changes the pathogen again in a constant host-pathogen adaptation and response process.