Dataset Information

Mucosal-Associated Invariant T Cells in the Human Gastric Mucosa and Blood: Role in Helicobacter pylori Infection.

ABSTRACT: Mucosal-associated invariant T (MAIT) cells represent a class of antimicrobial innate-like T cells that have been characterized in human blood, liver, lungs, and intestine. Here, we investigated, for the first time, the presence of MAIT cells in the stomach of children, adults, and the elderly undergoing routine endoscopy and assessed their reactivity to Helicobacter pylori (H. pylori?-?Hp), a major gastric pathogen. We observed that MAIT cells are present in the lamina propria compartment of the stomach and display a similar memory phenotype to blood MAIT cells. We then demonstrated that gastric and blood MAIT cells are able to recognize H. pylori. We found that CD8(+) and CD4(-)CD8(-) (double negative) MAIT cell subsets respond to H. pylori-infected macrophages stimulation in a MR-1 restrictive manner by producing cytokines (IFN-?, TNF-?, IL-17A) and exhibiting cytotoxic activity. Interestingly, we observed that blood MAIT cell frequency in Hp(+ve) individuals was significantly lower than in Hp(-ve) individuals. However, gastric MAIT cell frequency was not significantly different between Hp(+ve) and Hp(-ve) individuals, demonstrating a dichotomy between blood and gastric tissues. Further, we observed that the majority of gastric MAIT cells (>80%) expressed tissue-resident markers (CD69(+) CD103(+)), which were only marginally present on PBMC MAIT cells (<3%), suggesting that gastric MAIT cells are readily available to respond quickly to pathogens. These results contribute important new information to the understanding of MAIT cells function on peripheral and mucosal tissues and its possible implications in the host response to H. pylori.

SUBMITTER: Booth JS

PROVIDER: S-EPMC4585133 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Mucosal-Associated Invariant T Cells in the Human Gastric Mucosa and Blood: Role in Helicobacter pylori Infection.

Booth Jayaum S JS Salerno-Goncalves Rosangela R Blanchard Thomas G TG Patil Seema A SA Kader Howard A HA Safta Anca M AM Morningstar Lindsay M LM Czinn Steven J SJ Greenwald Bruce D BD Sztein Marcelo B MB

Frontiers in immunology 20150917

Mucosal-associated invariant T (MAIT) cells represent a class of antimicrobial innate-like T cells that have been characterized in human blood, liver, lungs, and intestine. Here, we investigated, for the first time, the presence of MAIT cells in the stomach of children, adults, and the elderly undergoing routine endoscopy and assessed their reactivity to Helicobacter pylori (H. pylori - Hp), a major gastric pathogen. We observed that MAIT cells are present in the lamina propria compartment of th ...[more]

PMID: 26441971

Similar Datasets

Project description:BackgroundOngoing Helicobacter pylori (HP) infection triggers a chronic active gastritis. Eradicating HP reduces gastric inflammation, but does not eliminate it. We sought to characterize this persistent gastritis, and demonstrate the persistence of HP-specific Th17 responses in individuals previously infected with HP but who no longer had evidence of ongoing infection.Methodology/principal findingsStudy subjects were divided into 3 groups 55 individuals had active HP infection (group A), 41 were diagnosed with previous HP infection (group P), and 59 were naïve to HP (group N). Blood and gastric tissue were obtained with written informed consent from all subjects, and immune responses were evaluated using flow cytometry, semi-quantitative real time PCR, immunofluorescent staining, ELISA, and multiplex cytometric bead array for cytokine quantification. Elevated IL-17A responses were observed in patients from group A compared to group N. Interestingly, IL-17A responses remained persistently elevated in the blood and gastric mucosa of individuals from group P, despite the absence of ongoing HP infection. Using purified CD4(+) T cells as effectors and antibodies that blocked antigen presentation by MHC Class II, we showed that these persistent IL-17A responses were mediated primarily by HP-specific Th17 cells, rather than other immune cells that have also been described to secrete IL-17A. Gastric mucosal IL-1? levels were also persistently elevated in group P, and neutralisation of IL-1? reduced the HP-specific IL-17A response of purified CD4(+) T cells to autologous HP-pulsed antigen presenting cells in vitro, suggesting a functional association between IL-1? and the persistent Th17 response in group P patients.Conclusions/significanceDespite lack of ongoing HP infection, HP-specific Th17 cells persist in the blood and gastric mucosa of individuals with past HP infection. We speculate that this persistent inflammation might contribute to gastric mucosal pathology, for example, persistent increased gastric cancer risk despite eradication of HP.

Dataset Information

Mucosal-Associated Invariant T Cells in the Human Gastric Mucosa and Blood: Role in Helicobacter pylori Infection.

Publications

Mucosal-Associated Invariant T Cells in the Human Gastric Mucosa and Blood: Role in Helicobacter pylori Infection.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets