PT  - JOURNAL ARTICLE
AU  - Cook, Katherine W
AU  - Letley, Darren P
AU  - Ingram, Richard J M
AU  - Staples, Emily
AU  - Skjoldmose, Helle
AU  - Atherton, John C
AU  - Robinson, Karen
TI  - CCL20/CCR6-mediated migration of regulatory T cells to the <em>Helicobacter pylori</em>-infected human gastric mucosa
AID  - 10.1136/gutjnl-2013-306253
DP  - 2014 Oct 01
TA  - Gut
PG  - 1550--1559
VI  - 63
IP  - 10
4099  - http://gut.bmj.com/content/63/10/1550.short
4100  - http://gut.bmj.com/content/63/10/1550.full
SO  - Gut2014 Oct 01; 63
AB  - Background Helicobacter pylori-induced peptic ulceration is less likely to occur in patients with a strong gastric anti-inflammatory regulatory T cell (Treg) response. Migration of Tregs into the gastric mucosa is therefore important. Objective To identify the homing receptors involved in directing Tregs to the gastric mucosa, and investigate how H pylori stimulates the relevant chemokine responses. Design Gastric biopsy samples and peripheral blood were donated by 84 H pylori-infected and 46 uninfected patients. Luminex assays quantified gastric biopsy chemokine concentrations. Flow cytometry was used to characterise homing receptors on CD4+CD25hi Tregs. H pylori wild-type and isogenic mutants were used to investigate the signalling mechanisms behind CCL20 and IL-8 induction in gastric epithelial cell lines. Transwell assays were used to quantify Treg migration towards chemokines in vitro. Results CCL20, CXCL1-3 and IL-8 concentrations were significantly increased in gastric biopsy samples from H pylori-infected patients. CCR6 (CCL20 receptor), CXCR1 and CXCR2 (IL-8 and CXCL1-3 receptors) were expressed by a higher proportion of peripheral blood Tregs in infected patients. Most gastric Tregs expressed these receptors. H pylori induced CCL20 production by gastric epithelial cells via cag pathogenicity island (cagPAI)-dependent NF-κB signalling. Foxp3+, but not Foxp3−, CD4 cells from infected mice migrated towards recombinant CCL20 in vitro. Conclusions As well as increasing Treg numbers, H pylori infection induces a change in their characteristics. Expression of CCR6, CXCR1 and CXCR2 probably enables their migration towards CCL20 and IL-8 in the infected gastric mucosa. Such qualitative changes may also explain how H pylori protects against some extragastric inflammatory disorders.