Background: Little information is currently available on the contribution of locally generated inflammatory and chemotactic cytokines to endothelial cell activation and subsequent neutrophil transendothelial migration in patients with Helicobacter pylori (H. pylori)-associated gastritis.
Methods: The contents of interleukin (IL)-1beta and IL-8 in the organ culture supernatants of antral mucosal tissues were measured with an enzyme-linked immunosorbent assay. The effects of the endogenous IL-1beta and IL-8 in mucosal tissues on neutrophil adherence and transendothelial migration were investigated using an experimental model of human umbilical vein endothelial cells (HUVEC).
Results: The contents of IL-1beta and IL-8 in organ cultures of antral mucosal tissues were significantly higher in patients with H. pylori infection than in those without infection. The organ culture supernatants from H. pylori-positive patients induced the expression of intercellular adhesion molecule-1 mRNA in HUVEC with increased binding of neutrophils, and these stimulatory effects were inhibited when HUVEC were pretreated with a nuclear factor-kappaB inhibitor, MG-132. Moreover, neutrophil adherence to HUVEC induced by the supernatants decreased after preincubation with neutralizing anti-IL-1beta antibody. As compared with the supernatants from H. pylori-negative patients, the samples from H. pylori-positive patients exhibited a significantly higher chemotactic activity for neutrophils, which was inhibited almost completely by preincubation of the supernatants with anti-IL-8 antibody.
Conclusions: Locally generated IL-1beta and IL-8 could coordinate with each other during the process of neutrophil infiltration into the gastric mucosa in patients with H. pylori infection.