Site-specific differences in T lymphocyte composition of the gastric mucosa after Helicobacter pylori eradication

In our earlier work, we revealed that inflammation of the lesser curvature of the gastric body and antrum could constitute independent risk factors for gastric cancer development, while inflammation of the greater curvature was not. The aims of this study were as follows: first, to reveal the differences between T lymphocyte populations of the gastric antrum and the greater and lesser curvatures of the gastric body in patients after Helicobacter pylori eradication; second, to analyze the correlation between the composition of the stomach-resident T lymphocytes and time from H. pylori eradication; and third, to evaluate the sex differences in T lymphocyte subsets after H. pylori eradication. To investigate site-specific differences in stomach-resident T lymphocytes after H. pylori eradication, we performed flow cytometry analysis on samples taken from the gastric antrum, greater curvature of the gastric body, and lesser curvature of the gastric body of 20 patients. We also analyzed the correlation between the composition of the stomach-resident T lymphocytes and the time from H. pylori eradication. The lymphocyte subsets of the antrum and lesser curvature of the body were similar. In contrast, compared to those in the greater curvature of the gastric body, CD4(+)/CD3(+) lymphocyte subsets (43.8 ± 19.4% vs 31.7 ± 14.6%) were elevated in the lesser curvature of the body, whereas CD8(+)/CD3(+) (67.1 ± 21.3% vs 80.4 ± 12.0%), CD7(+)/CD3(+) (91.2 ± 4.6% vs 93.7 ± 3.8%), CCR4(+)/CD3(+) (7.7 ± 8.1% vs 10.4 ± 7.0%), CD45RA(+)/CD3(+)CD4(+) (27.2 ± 24.8% vs 39.5 ± 20.8%), and CD45RA(+)/CD3(+)CD4(−) (14.2 ± 11.1% vs 18.7 ± 11.5) were lower. Linear regression analysis showed a negative correlation between the time after H. pylori eradication and CD4(+)/CD3(+) (P < .05, R(2) = 0.198). There were no significant differences between men and women with respect to the lymphocyte populations. These results indicate that there are site-specific differences in lymphocyte composition in the stomach after H. pylori eradication.