interleukin-8 and Duodenitis

There is no direct evidence for an animal model of Helicobacter pylori induced duodenal ulcer.. In this study we evaluated the roles of bacterial strain and age of experimental animals in induction of duodenitis and duodenal ulcer in Mongolian gerbils after H pylori infection.. Specific pathogen free Mongolian gerbils were inoculated orally with three bacterial strains (H pylori ATCC 43504, TN2GF4, and K-6, a clinical isolate from a patient with gastric cancer in our clinic). These strains have both the cagA gene and VacA. Five week old gerbils were used to emulate prematurity infection and 14 week old animals were used as mature test subjects. Animals were observed for 12 weeks after inoculation. Interleukin 8 (IL-8) production in gastric epithelial cells (MKN74) after coculture with the H pylori strains was measured by ELISA.. Gastritis and gastric ulcers were found in all gerbils infected with the three strains. However, duodenitis and gastric metaplasia were seen more frequently in gerbils infected with TN2GF4 and K-6 strains than in the ATCC 43504 infected or control groups (p<0.05). Superficial duodenal ulcers with severe duodenitis and gastric metaplasia were found in two gerbils inoculated at 14 weeks with the TN2GF4 strain but none at five weeks. The TN2GF4 strain stimulated significantly higher levels of IL-8 than ATCC 43504 and K6 strains (p=0.0039).. When injected into adult Mongolian gerbils, a specific strain (TN2GF4) of H pylori can induce duodenitis with gastric metaplasia and superficial duodenal ulcers. Induction of duodenal ulcer in an animal model fulfills the requirements of Koch's postulates for establishing a role for H pylori as a causative agent.

Topics: Age Factors; Animals; Coculture Techniques; Disease Models, Animal; Duodenal Ulcer; Duodenitis; Gastric Mucosa; Gerbillinae; Helicobacter Infections; Helicobacter pylori; Interleukin-8; Male; Metaplasia

Helicobacter pylori (H. pylori) appears to initiate an inflammatory cascade. Thus, phagocytes are accumulated in the gastric mucosa, in inflammatory conditions. Further, a potent chemotactic mediator, interleukin 8 (IL-8) is synthesized at such sites. The recently described IL-8 autoantibodies may, however, counteract the pro-inflammatory actions of IL-8. The aim was to study the correlation between H. pylori infection and IL-8, together with IL-8 autoantibodies in two different populations from a developed and a developing country.. Two different endoscopically characterized populations (65 Danes and 89 Albanians) were examined. IL-8 and IL-8 autoantibodies were detected by ELISA techniques, and H. pylori was identified by histological examinations.. Significantly more Albanian controls and dyspeptic patients (80 out of 89 persons) were H. pylori positive as compared to 24 of 65 Danes (p < 0.001). The median IL-8 level among Albanian controls 349 pg/mg protein was significantly higher than among Danes < 61 pg/mg protein (p < 0.001), and was at the same level as found in Danish peptic ulcer patients (p > 0.05). Further, H. pylori positive patients from both countries had significantly higher levels of IL-8 as compared to H. pylori negative patients (p < 0.001). However, significantly higher levels of IL-8 autoantibodies were found in the Albanian sub-population (median 138 O.D. units versus 52 O.D. units among Danes) (p < 0.001).. In H. pylori related disorders, a high mucosal IL-8 production has been found. However, this investigation further demonstrates higher levels of IL-8 autoantibodies among dyspeptic patients from a developing country, which might possibly counteract the pro-inflammatory actions of IL-8 by binding the molecule. The physiological significance of an altered immune response as described here needs to be elucidated in future studies.

Topics: Adolescent; Adult; Aged; Autoantibodies; Duodenal Ulcer; Duodenitis; Female; Gastric Mucosa; Gastritis; Helicobacter Infections; Helicobacter pylori; Humans; Interleukin-8; Male; Middle Aged; Stomach Ulcer

To investigate the expression of interleukin-8 (IL-8) in Helicobacter pylori infected normal and neoplastic gastroduodenal mucosa, and in established gastric cancer cell lines.. Immunofluorescence techniques were used to localise IL-8 in cryosections of gastric (n = 25) and duodenal (n = 17) endoscopic biopsy specimens an in resected gastric tumour tissue samples from 16 patients. Two gastric cancer cell lines (Kato 3 and MKN 45) were examined for IL-8 protein expression by immunofluorescence and for the presence of IL-8 mRNA by reverse transcription followed by the polymerase chain reaction (RT-PCR).. IL-8 was localised to the epithelium in histologically normal gastric mucosa, with particularly strong expression in the surface cells. IL-8 expression was also a feature of surface epithelium in the duodenal bulb, but was much reduced in the second part of the duodenum. In chronic H pylori-associated gastritis gastritis gastric epithelial IL-8 expression was increased and expression of IL-8 within the lamina propria was evident. By contrast, large areas of IL-8 negative epithelium were observed in the body mucosa of a subject with Ménétrier's disease. In gastric carcinoma the tumour cells were positive for IL-8. IL-8 was also detected by immunofluorescence in unstimulated Kato 3 and MKN 45 cells, and constitutive IL-8 gene expression in these cell lines was confirmed by detection of IL-8 mRNA by RT-PCR.. Immunoreactive IL-8, a potent neutrophil chemotactic and activating factor, is present in the epithelium of both normal and inflamed gastric mucosa with increased expression in the latter. There is site dependent variation in epithelial IL-8 expression within the gastroduodenal mucosa. The expression of the pro-inflammatory cytokine IL-8 in gastric carcinoma cells may influence peritumoural cellular infiltrates.

Topics: Base Sequence; Chronic Disease; Duodenitis; Duodenum; Fluorescent Antibody Technique; Gastric Mucosa; Gastritis; Helicobacter Infections; Helicobacter pylori; Humans; Interleukin-8; Intestinal Mucosa; Molecular Sequence Data; RNA, Neoplasm; Stomach Diseases; Stomach Neoplasms; Tumor Cells, Cultured