MUCOSAL IGA ANTIBODY AGAINST HELICOBACTER-PYLORI IN CHRONIC GASTRITISAND INTESTINAL METAPLASIA DETECTED BY THE TES-TAPE METHOD IN RESECTION SPECIMENS AFTER GASTRECTOMY FOR GASTRIC-CANCER

Background. Subjects with atrophic body gastritis have a high prevalen ce of Helicobacter pylori seropositivity and a low prevalence of H. py lori infection. Disappearance of the organism appears to correlate wit h the development of intestinal metaplasia. To investigate this point, intestinal metaplasia was biochemically subclassified into complete a nd incomplete types by the Tes-Tape method, and tissue IgA and IgG ant ibodies against H. pylori were measured by enzyme-linked immunosorbent assay (ELISA). Methods. Twenty-five stomachs resected for gastric can cer were examined using the Tes-Tape method. Serum H. pylori IgA and I gG antibodies and tissue IgA and IgG antibodies against H. pylori and tissue secretory IgA (sc-IgA) were examined in areas of intestinal met aplasia, 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 in testinal metaplasia and was positive in 6 of 14 (43%) nonmetaplastic g astric mucosa from the antrum and 14 of 23 (61%) from the body. Duoden al mucosa and cancer tissue were positive for tissue IgA antibody in 1 of 6 (17%) and 6 of 17 (0%), respectively. Tissue H. pylori IgG antib ody was negative in all the tissues examined. sc-IgA in the areas of i ntestinal metaplasia was 120 +/- 65 (mean +/- standard error; ng/mg we t weight) and in the nonmetaplastic gastric mucosa was 113 +/- 72, sho wing no difference. Positivity and negativity of serum IgA and IgG ant ibodies against H. pylori coincided with presence or absence of tissue IgA antibody in nonmetaplastic gastric mucosa in 15 of 19 (79%) and 1 6 of 19 (84%) patients examined, respectively. Conclusion. Positivity rates of tissue IgA antibody against H. pylori were lower in the mucos a of intestinal metaplasia than in nonmetaplastic gastric mucosa and w ere negative in carcinoma. No significant difference in levels of sc-I gA between intestinal metaplasia and nonmetaplastic gastric mucosa was found.