Comparison between in vivo and in vitro chemokine production in Helicobacter pylori infection

Background: Enhanced gastric mucosal chemokine activity has been demonstrat ed in patients with Helicobacter pylori infection. However, little is known about the mechanisms involved in this phenomenon. Aim: To examine whether in vivo chemokine activity is similar to in vitro r esponse of gastric epithelial cells infected by H. pylori. Patients and Methods: Antral biopsy specimens were obtained from patients w ith H. pylori infection for organ culture, isolation of H. pylori and histo logical examination. Results: In organ cultures of mucosal tissues, the levels of interleukin-8 and growth-related gene product a were elevated in patients with peptic ulc er disease compared with those with erosive gastritis or endoscopically nor mal mucosa. However, there were no significant differences in in vitro cult ures of MKN45 or KATO III cells that were infected with H. pylori isolated from these same patients. These in vivo and in vitro alpha-chemokine levels showed no significant association with the presence of cagA gene and CagA protein, ureB genotype, or binding capacity to MKN45 or KATO III cells in i ndividual H. pylori isolates. In contrast, in vivo mucosal alpha-chemokine activity correlated with H. pylori colonization density. Conclusion: Mucosal chemokine profiles and inflammatory responses in H. pyl ori infection may be associated more closely with host factors, including t hose determining bacterial adhesiveness, than with differences in H. pylori strains.