RESEARCH HIGHLIGHTS Nature Reviews Gastroenterology & Hepatology 11, 141 (2014); published online 4 February 2014; doi:10.1038/nrgastro.2014.13
HELICOBACTER PYLORI INFECTION
Helicobacter pylori induces changes in regulatory T cells
Courtesy of K. Robinson
Helicobacter pylori is able to induce changes in the characteristics of regulatory T (TREG) cells, according to a study published in Gut. “This might mean that people with H. pylori are more likely to have a well-controlled immune system, and have TREG cells that function in different ways from those who have never had the infection,” says Karen Robinson, corresponding author. TREG cells have an immunosuppressive function, and people infected with H. pylori tend to have increased numbers
of these cells in their gastric mucosa. Notably, Robinson and colleagues have previously shown that people with a poor TREG response are more likely to develop peptic ulceration. “We therefore wished to understand more about this response, how it is generated, and what drives these immunosuppressive cells to accumulate in the gastric mucosa,” explains Robinson. First, the researchers used an immunoassay to gather data on which chemokines might attract TREG cells to migrate out of the bloodstream and into the mucosa. Next, flow cytometry was used to investigate the types of chemokine receptors and other adhesion molecules expressed by TREG cells in the peripheral blood of infected and uninfected patients. One of the most notable findings from the study is that almost all TREG cells in the gastric mucosa of patients infected with H. pylori express the chemokine receptor CCR6, which enables them to respond to its ligand CCL20. “The bacteria trigger the expression of much more CCL20
NATURE REVIEWS | GASTROENTEROLOGY & HEPATOLOGY © 2014 Macmillan Publishers Limited. All rights reserved
in the gastric mucosa if they possess an important virulence factor called the cag pathogenicity island,” reports Robinson. The research team also demonstrated that TREG cells migrate towards a gradient of CCL20 in vitro, confirming that this cytokine is an important chemoattractant for these cells. These data on the differences in TREG cells between infected and uninfected patients could be behind some of the recent findings that H. pylori might actually be beneficial in preventing allergies and asthma in some cases. “We are investigating the quantitative and qualitative differences in TREG cell populations from infected and uninfected patients and looking at their associations with allergy,” concludes Robinson. Isobel Leake Original article Cook, K. W. et al. CCL20/CCR6-mediated migration of regulatory T cells to the Helicobacter pyloriinfected human gastric mucosa. Gut doi:10.1136/ gutjnl-2013-306253
VOLUME 11 | MARCH 2014
HELICOBACTER PYLORI INFECTION
Helicobacter pylori induces changes in regulatory T cells
Courtesy of K. Robinson
Helicobacter pylori is able to induce changes in the characteristics of regulatory T (TREG) cells, according to a study published in Gut. “This might mean that people with H. pylori are more likely to have a well-controlled immune system, and have TREG cells that function in different ways from those who have never had the infection,” says Karen Robinson, corresponding author. TREG cells have an immunosuppressive function, and people infected with H. pylori tend to have increased numbers
of these cells in their gastric mucosa. Notably, Robinson and colleagues have previously shown that people with a poor TREG response are more likely to develop peptic ulceration. “We therefore wished to understand more about this response, how it is generated, and what drives these immunosuppressive cells to accumulate in the gastric mucosa,” explains Robinson. First, the researchers used an immunoassay to gather data on which chemokines might attract TREG cells to migrate out of the bloodstream and into the mucosa. Next, flow cytometry was used to investigate the types of chemokine receptors and other adhesion molecules expressed by TREG cells in the peripheral blood of infected and uninfected patients. One of the most notable findings from the study is that almost all TREG cells in the gastric mucosa of patients infected with H. pylori express the chemokine receptor CCR6, which enables them to respond to its ligand CCL20. “The bacteria trigger the expression of much more CCL20
NATURE REVIEWS | GASTROENTEROLOGY & HEPATOLOGY © 2014 Macmillan Publishers Limited. All rights reserved
in the gastric mucosa if they possess an important virulence factor called the cag pathogenicity island,” reports Robinson. The research team also demonstrated that TREG cells migrate towards a gradient of CCL20 in vitro, confirming that this cytokine is an important chemoattractant for these cells. These data on the differences in TREG cells between infected and uninfected patients could be behind some of the recent findings that H. pylori might actually be beneficial in preventing allergies and asthma in some cases. “We are investigating the quantitative and qualitative differences in TREG cell populations from infected and uninfected patients and looking at their associations with allergy,” concludes Robinson. Isobel Leake Original article Cook, K. W. et al. CCL20/CCR6-mediated migration of regulatory T cells to the Helicobacter pyloriinfected human gastric mucosa. Gut doi:10.1136/ gutjnl-2013-306253
VOLUME 11 | MARCH 2014
