ERADICATION OF HELICOBACTER-PYLORI BY LOC AL SECRETORY IMMUNE-RESPONSE

54 patients (22 females, 32 males, age 21-79, mean 45 years) referred for upper gastrointestinal endoscopy were investigated. Helicobacter p ylori (HP) infection was determined using histology (H&E and Giemsa st ain), rapid urease test (CLO) and serology (Cobas Core Anti-H. pylori EIA). Density of HP colonization was determined in gastric antral (3 b iopsy specimens) and body mucosa (2 biobsy specimens) and semiquantita tively graded on a scale of 0 to 3. Gastric colonization was obtained by addition of the two scores. IgA anti-HP concentration was determine d by ELISA using the same FPLC purified HP-antigen mixture as for sero logy Gastric juice IgA anti-HP concentration in HP-positive patients ( n = 40) was significantly higher than in HP-negative (n = 14) patients (38,3+/-4,6 vs. 5,4+/-1,2 relative units, p<0.001). Comparison of HP- colonization density of gastric mucosa with gastric juice IgA anti-HP concentration of the 54 patients by binominal regression analysis yiel ded a correlation coefficient of 0.65 (p<0.01). The biphasic course of the curve suggests a mutual relationship of HP-colonization density a nd IgA immune response. Increasing colonization densities seemed to in duce increasing secretory immune responses. Half-maximal and higher im mune responses, however, seemed to suppress further HP colonization in vivo without eradicating the infection.