Background: Subjects with atrophic body gastritis have a high prevalence of Helicobacter pylori seropositivity and a low prevalence of H. pylori infection. Disappearance of the organism appears to correlate with the development of intestinal metaplasia. To investigate this point, intestinal metaplasia was biochemically subclassified into complete and incomplete types by the Tes-Tape method, and tissue IgA and IgG antibodies against H. pylori were measured by enzyme-linked immunosorbent assay (ELISA).
Methods: Twenty-five stomachs resected for gastric cancer were examined using the Tes-Tape method. Serum H. pylori IgA and IgG antibodies and tissue IgA and IgG antibodies against H. pylori and tissue secretory IgA (sc-IgA) were examined in areas of intestinal metaplasia, nonmetaplastic gastric mucosa, and gastric carcinoma by ELISA:
Results: Tissue H. pylori IgA antibody was positive in 6 of 19 (32%) specimens taken from complete and 2 of 7 (29%) incomplete types of intestinal metaplasia and was positive in 6 of 14 (43%) nonmetaplastic gastric mucosa from the antrum and 14 of 23 (61%) from the body. Duodenal mucosa and cancer tissue were positive for tissue IgA antibody in 1 of 6 (17%) and 0 of 17 (0%), respectively. Tissue H. pylori IgG antibody was negative in all the tissues examined. sc-IgA in the areas of intestinal metaplasia was 120 +/- 65 (mean +/- standard error; ng/mg wet weight) and in the nonmetaplastic gastric mucosa was 113 +/- 72, showing no difference. Positivity and negativity of serum IgA and IgG antibodies against H. pylori coincided with presence or absence of tissue IgA antibody in nonmetaplastic gastric mucosa in 15 of 19 (79%) and 16 of 19 (84%) patients examined, respectively.
Conclusion: Positivity rates of tissue IgA antibody against H. pylori were lower in the mucosa of intestinal metaplasia than in nonmetaplastic gastric mucosa and were negative in carcinoma. No significant difference in levels of sc-IgA between intestinal metaplasia and non-metaplastic gastric mucosa was found.