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Detrimental effect of systemic antimicrobial CD4⁺ T-cell reactivity on gut epithelial integrity.

ABSTRACT: Healthy host-microbe mutualism relies on compartmentalization and proper regulation of systemic and mucosal immune responses. Nevertheless, the systemic immune system is frequently exposed to bouts of bacteraemia, which can trigger systemic antimicrobial immune reactivity including CD4⁺ T cells. Low-level bacteraemia can occur when immune compartmentalization is compromised, for example in the presence of innate immune deficiency or following use of non-steroidal anti-inflammatory drugs. We generated an Escherichia coli strain expressing a defined T helper neo-epitope to study systemic antigen-specific antimicrobial CD4⁺ T cells and their potential involvement in the pathogenisis of inflammatory bowel diseases. We found that the dose of bacteria required for the induction of systemic antimicrobial CD4⁺ T-cell proliferation was high and not easily reached under physiological conditions. Importantly, however, when intestinal barrier function was compromised by induced damage to the intestinal epithelium, the presence of systemic antimicrobial CD4⁺ T cells specific for a single neo-antigen resulted in dramatically increased levels of bacterial translocation. This study therefore demonstrates that systemic antimicrobial CD4⁺ T-cell reactivity might impact adversely on the mucosa under conditions of reduced barrier function and that despite strong mucosal immune regulation, antigen-specific recognition is still sensitive.

SUBMITTER: Kwong Chung CK

PROVIDER: S-EPMC5214769 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Detrimental effect of systemic antimicrobial CD4<sup>+</sup> T-cell reactivity on gut epithelial integrity.

Kwong Chung Cheong K C CK Ronchi Francesca F Geuking Markus B MB

Immunology 20161125 2

Healthy host-microbe mutualism relies on compartmentalization and proper regulation of systemic and mucosal immune responses. Nevertheless, the systemic immune system is frequently exposed to bouts of bacteraemia, which can trigger systemic antimicrobial immune reactivity including CD4<sup>+</sup> T cells. Low-level bacteraemia can occur when immune compartmentalization is compromised, for example in the presence of innate immune deficiency or following use of non-steroidal anti-inflammatory dru ...[more]

PMID: 27779311

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Dataset Information

Detrimental effect of systemic antimicrobial CD4⁺ T-cell reactivity on gut epithelial integrity.

Publications

Detrimental effect of systemic antimicrobial CD4<sup>+</sup> T-cell reactivity on gut epithelial integrity.

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Dataset Information

Detrimental effect of systemic antimicrobial CD4+ T-cell reactivity on gut epithelial integrity.

Publications

Detrimental effect of systemic antimicrobial CD4<sup>+</sup> T-cell reactivity on gut epithelial integrity.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets

Detrimental effect of systemic antimicrobial CD4⁺ T-cell reactivity on gut epithelial integrity.