M. Noshiro et al., Gastric metaplasia in the duodenal bulb shows increased mucosal interleukin-8 activity in Helicobacter pylori-positive duodenal ulcer patients, SC J GASTR, 35(5), 2000, pp. 482-489
Background: Although increased levels of interleukin (IL)-8 are known to be
associated with infiltration of neutrophils in the gastric mucosa with Hel
icobacter pylori infection, no study has investigated the relationship betw
een local IL-8 levels and neutrophil infiltration in the duodenal mucosa of
patients with duodenal ulcer (DU). Methods: Duodenal mucosal biopsy specim
ens with and without gastric metaplasia (GM) were obtained from patients wi
th DU and controls with an endoscopic methylene blue (MB) staining method.
Levels of IL-8 secreted in the organ cultures of biopsy specimens were meas
ured with an enzyme-linked immunosorbent assay. The number of myeloperoxido
se-positive neutrophils infiltrating the lamina propria was determined in i
mmunohistochemically stained tissue sections. Results: Histologic assessmen
t showed that there was a strong correlation between the absence of endosco
pic MB staining and the extent of GM. The levels of IL-8 in both duodenal a
nd antral mucosal tissues were significantly higher in patients with H. pyl
ori infection than in those without infection. In patients with DU the duod
enal mucosal tissues with GM (MB-unstained mucosa) showed significantly hig
her levels of IL-8 than those without GM (MB-stained mucosa) or the antral
mucosa. The number of neutrophils showed similar variations among DU and co
ntrol patients with a positive correlation with IL-S activity. The levels o
f IL-I and the number of neutrophils decreased after H. pylori eradication
in both duodenal and antral mucosal tissues, and these changes were more re
markable in the duodenal mucosal tissues with GM. Conclusions: Increased IL
-8 activity in the duodenal mucosa with GM may be important for ulcerogenes
is in H. pylori-positive DU patients.