Increased Frequency of Antral CD4⁺ T and CD19⁺ B Cells in Patients with Helicobacter pylori‐Related Peptic Ulcer Disease

Abstract

Only a fraction of Helicobacter pylori (HP)-infected individuals develop clinical disease. Recent research indicates that immunological mechanisms may be important for understanding the pathophysiology of HP infection. Differences in the individual cellular immune response may reflect the clinical diversity. The aim of the present study was to investigate the cellular immune response against HP in three clinically well-defined patient groups: HP-positive peptic ulcer, HP-positive and HP-negative gastritis. Biopsies from gastric mucosa were processed for analysis by flow cytometry and histology. The number of T lymphocytes (CD3 þ ) was significantly higher in HP-positive peptic ulcer (13.8%) than in HP-positive nonulcer gastritis (6.3%). A nonsignificant increase for B lymphocytes (CD19 þ ) was noted as well. Furthermore, a significant difference was seen in mucosal CD4/CD8 ratio between HP ulcer (2.4) and nonulcer HP gastritis (1.0) patients. Thus, B cells (CD19 þ ) and T-helper cells (CD4 þ ) were dominant in gastric mucosa from peptic ulcer patients, and cytotoxic T cells (CD8 þ ) were relatively dominant in gastric mucosa from nonulcer patients. In conclusion, distinct differences in the T-cell subset distribution of mucosal lymphocytes were detected in patients with HP infection, strongly correlated with the presence or absence of peptic ulcer.

Characterization and Functional Properties of Gastric Tissue-Resident Memory T Cells from Children, Adults, and the Elderly

“…Therefore, there was an inversion in the CD4/CD8 ratio in LPMC (~1:3) compared to PBMC (~3:1). These results confirmed and extended those reported by others (16, 19, 20) by showing that these differences were observed in all age groups (Figure 3B). When CD4 + T cells in LPMC of children and the elderly were compared to adults, children showed a significantly higher frequency of these cells (Figure 3B).…”

“…Consistent with previous reports, the frequency of CD3 + cells was lower as a percentage of total LPMC cells in the gastric mucosa than in PBMC (19, 31). Additionally, CD4 + and CD8 + T cells from gastric LPMC were found at similar frequencies as reported by others (14, 16) and the vast majority of gastric CD8 + and CD4 + T cells showed a T EM phenotype (CD62L − , CD45RA − ).…”

“…For example, intestinal Mϕ is more phagocytic and bactericidal but secrete less pro-inflammatory cytokines than their peripheral blood counterparts (18). Additionally, the CD4 + /CD8 + ratio is inverted (~1:3) in gastric LPMC (from healthy volunteers) compared to peripheral blood mononuclear cells (PBMC) (~3:1) (16, 19, 20). Despite these observations, very little is known about the different T cell subsets present in the gastric mucosa of healthy humans.…”

Helicobacter pylori Infection Increases Frequency of PDCA-1+ (CD317+) B-cell Subsets

“…Therefore, this study characterized the relative frequency of the different CD19 þ subsets in peripheral blood. We found that compared to uninfected subjects, H. pylori infection is associated with expansion of these cells in line with the previous observations (23,24). Importantly, however, we now report that this increase is at least partly mediated by increase in the PDCA-1 þ B-cell compartment.…”

Cathepsin X-deficient Gastric Epithelial Cells in Co-culture with Macrophages

“…In addition to macrophages, T-and B-lymphocytes were recruited in the wake of inflammatory response (26). Our gene expression microarray analysis of H. pylori-infected WT and Ctsx Ϫ/Ϫ epithelial cells revealed B-and T-cell specific gene expression signatures that clearly discriminated from uninfected cells.…”