Expression of Neutrophil-activating Chemokines in Human Neutrophils by Helicobacter pylori Water Extract

Kim, Joo Sung; Jun, Hyun Chae; Kim, Jung Mogg; Choi, Il Ju; Song, In Sung; Kim, Chung Yong

Abstract

BACKGROUND/AIMS: To elucidate mechanisms of the persistent neutrophil recruitment in Helicobacter pylori (H. pylori)-infected gastric mucosa, we evaluated the activation of human neutrophils and expression of neutrophil-activating chemokines in neutrophils by H. pylori water extract (HPWE).
METHODS
HPWE was prepared from extraction of H. pylori surface proteins in distilled water. Human neutrophils were obtained from healthy volunteers by Ficoll-Hypaque density gradient separation. After neutrophils were stimulated with HPWE, mobilization of intracellular free calcium, expression of lymphocyte function-associated antigen-1beta and secretion of myeloperoxidase (MPO) were determined in neutrophils. Electron microscopic findings and MPO levels were also evaluated in H. pylori-infected gastric mucosa. Expression of interleukin-8 (IL-8) and growth-related oncogenes (GROs; GRO alpha, GRObeta and GROgamma) mRNA and protein was assessed by quantitative reverse transcription-polymerase chain reaction or enzyme linked immunosorbent assay.
RESULTS
HPWE enhanced the neutrophil activity in vitro and MPO levels in gastric mucosa were significantly correlated with H. pylori density or neutrophil activity. HPWE also upregulated the expression of IL-8 and GROs mRNA and protein by neutrophils.
CONCLUSIONS
H. pylori-induced neutrophil recruitment may be mediated via neutrophil-activating chemokines expressed by neutrophils activated by H. pylori water-soluble surface proteins.