The Bacterial Species Campylobacter jejuni Induce Diverse Innate Immune Responses in Human and Avian Intestinal Epithelial Cells

ABSTRACT Enterohepatic Helicobacter species infect the intestinal tracts and biliary trees of various mammals, including mice and humans, and are associated with chronic inflammatory diseases of the intestine, gallstone formation, and malignant transformation. The recent analysis of the whole genome sequence of the mouse enterohepatic species Helicobacter hepaticus allowed us to perform a functional analysis of bacterial factors that may play a role in these diseases. We tested the hypothesis that H. hepaticus suppresses or evades innate immune responses of mouse intestinal epithelial cells, which allows this pathogen to induce or contribute to chronic inflammatory disease. We demonstrated in the present study that the innate immune responses of intestinal epithelial cells to lipopolysaccharide (LPS) via Toll-like receptor 4 (TLR4) and to flagellin-mediated activation via TLR5 are reduced by H. hepaticus infection through soluble bacterial factors. In particular, H. hepaticus lysate and the soluble component LPS antagonized TLR4- and TLR5-mediated immune responses of intestinal epithelial cells. H. hepaticus lysate and LPS inhibited development of endotoxin tolerance to Escherichia coli LPS. Suppression of innate immune responses by H. hepaticus LPS thus may affect intestinal responses to the resident microbial flora, epithelial homeostasis, and intestinal inflammatory conditions.

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Microarray analysis of differentially expressed transcripts in porcine intestinal epithelial cells (IPEC-J2) infected with porcine sapelovirus as a model to study innate immune responses to enteric viruses

Archives of Virology ◽

10.1007/s00705-013-1638-2 ◽

2013 ◽

Vol 158 (7) ◽

pp. 1467-1475 ◽

Cited By ~ 7

Author(s):

Daoliang Lan ◽

Cheng Tang ◽

Hua Yue ◽

Huan Sun ◽

Li Cui ◽

...

Keyword(s):

Epithelial Cells ◽

Immune Responses ◽

Microarray Analysis ◽

Intestinal Epithelial Cells ◽

Enteric Viruses ◽

Innate Immune ◽

Differentially Expressed ◽

Intestinal Epithelial ◽

Innate Immune Responses ◽

Porcine Sapelovirus

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A30 DIFFERENCES BETWEEN HUMAN AND MOUSE INTESTINAL EPITHELIAL CELLS IN THEIR INNATE IMMUNE RESPONSES TO BACTERIAL AND HOST STIMULI.

Journal of the Canadian Association of Gastroenterology ◽

10.1093/jcag/gwab002.029 ◽

2021 ◽

Vol 4 (Supplement_1) ◽

pp. 2-3

Author(s):

J M Allaire ◽

A Poon ◽

S M Crowley ◽

X Han ◽

M Stahl ◽

...

Keyword(s):

Epithelial Cells ◽

Immune Responses ◽

Inflammatory Responses ◽

Intestinal Epithelial Cells ◽

Innate Immune ◽

Negative Regulator ◽

Intestinal Epithelial ◽

Innate Immune Responses ◽

Transformed Cell Lines ◽

First Time

Abstract Background Intestinal epithelial cells (IEC) reside in close contact with the gut microbiota. It is thus important that IEC are hypo-responsive to bacterial products to prevent maladaptive inflammatory responses in the gut, such as those seen in Inflammatory bowel diseases (IBD). This suppression of innate immune signaling in IEC is in part due to their strong expression of Single Ig IL1 related receptor (SIGIRR), a negative regulator of interleukin (IL)-1 and toll-like receptor (TLR) signaling. IL37, a newly recognized anti-inflammatory cytokine has been shown to strongly inhibit innate signaling in cells by binding to, and signaling through SIGIRR, leading to suppression of various forms of inflammation in mice. Few studies have looked at the function of IL-37/SIGIRR in IEC and their potential use to balance inflammatory responses. Notably, while many groups have studied IEC immune response in vitro, using transformed IEC lines, our focus is on primary-derived IEC which more accurately reflect in vivo responses. Aims To characterize IEC intrinsic and species-specific immune responses elicited by bacteria and host products as well as the role of IL37/SIGIRR in regulating this innate signaling. Methods We used organoid to study the innate immune responses of primary IEC derived from human or mouse colon (colonoids). After stimulation with inflammatory stimuli (IL1β, FliC and LPS), qPCR, ELISA, Milliplex Multiplex Assay and Western blot were used to determine modification in signalling pathway and cytokine/chemokine secretion. Results Using colonoids derived from healthy donors, we demonstrated that unlike transformed cell lines or mouse IEC, human IEC respond only to the bacterial product FliC, and not to LPS or IL1β. We further characterized human colonoid innate immune responses and despite significant inter-individual variability upon FliC stimulation, all organoids released several chemokines (IL8, CXCL1, CXCL2, CCL2 and CCL20). We showed for the first time that IL37 attenuated these innate immune responses through inhibition of intracellular signaling pathways (p38 and NFkB). Using colonoids derived from wildtype and Sigirr deficient mice, we found that mice IEC were responsive to IL1b and FliC and that the suppressive effects of IL37 were Sigirr dependent. Conclusions Our results show that human IEC show variability among individuals in the magnitude of their innate immune responses, and these responses differ from those obtained from transformed cells and primary mouse IEC. For the first time, we show that IL37 suppresses IEC innate immune responses, through its ability to signal through Sigirr. Further investigations will assess the ability of IL37 to control inflammation of IEC derived from IBD patients, as a potential therapeutic to promote gut health. Funding Agencies CAG, CIHRMSFHR

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Ligilactobacillus salivarius Strains Isolated From the Porcine Gut Modulate Innate Immune Responses in Epithelial Cells and Improve Protection Against Intestinal Viral-Bacterial Superinfection

Frontiers in Immunology ◽

10.3389/fimmu.2021.652923 ◽

2021 ◽

Vol 12 ◽

Author(s):

Yuhki Indo ◽

Shugo Kitahara ◽

Mikado Tomokiyo ◽

Shota Araki ◽

Md. Aminul Islam ◽

...

Keyword(s):

Immune Response ◽

Epithelial Cells ◽

Immune Responses ◽

Innate Immune ◽

Intestinal Epithelial ◽

Innate Immune Responses ◽

Rotavirus Infection ◽

Intestinal Infections ◽

Immune Health

Previously, we constructed a library of Ligilactobacillus salivarius strains from the intestine of wakame-fed pigs and reported a strain-dependent capacity to modulate IFN-β expression in porcine intestinal epithelial (PIE) cells. In this work, we further characterized the immunomodulatory activities of L. salivarius strains from wakame-fed pigs by evaluating their ability to modulate TLR3- and TLR4-mediated innate immune responses in PIE cells. Two strains with a remarkable immunomodulatory potential were selected: L. salivarius FFIG35 and FFIG58. Both strains improved IFN-β, IFN-λ and antiviral factors expression in PIE cells after TLR3 activation, which correlated with an enhanced resistance to rotavirus infection. Moreover, a model of enterotoxigenic E. coli (ETEC)/rotavirus superinfection in PIE cells was developed. Cells were more susceptible to rotavirus infection when the challenge occurred in conjunction with ETEC compared to the virus alone. However, L. salivarius FFIG35 and FFIG58 maintained their ability to enhance IFN-β, IFN-λ and antiviral factors expression in PIE cells, and to reduce rotavirus replication in the context of superinfection. We also demonstrated that FFIG35 and FFIG58 strains regulated the immune response of PIE cells to rotavirus challenge or ETEC/rotavirus superinfection through the modulation of negative regulators of the TLR signaling pathway. In vivo studies performed in mice models confirmed the ability of L. salivarius FFIG58 to beneficially modulate the innate immune response and protect against ETEC infection. The results of this work contribute to the understanding of beneficial lactobacilli interactions with epithelial cells and allow us to hypothesize that the FFIG35 or FFIG58 strains could be used for the development of highly efficient functional feed to improve immune health status and reduce the severity of intestinal infections and superinfections in weaned piglets.

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Campylobacter jejuni Translocation across Intestinal Epithelial Cells Is Facilitated by Ganglioside-Like Lipooligosaccharide Structures

Infection and Immunity ◽

10.1128/iai.06270-11 ◽

2012 ◽

Vol 80 (9) ◽

pp. 3307-3318 ◽

Cited By ~ 26

Author(s):

Rogier Louwen ◽

Edward E. S. Nieuwenhuis ◽

Leonie van Marrewijk ◽

Deborah Horst-Kreft ◽

Lilian de Ruiter ◽

...

Keyword(s):

Epithelial Cells ◽

Campylobacter Jejuni ◽

Intestinal Epithelial Cells ◽

Bacterial Species ◽

Intestinal Epithelial ◽

Content Type ◽

Epithelial Cell Lines ◽

Severe Gastroenteritis ◽

Bloody Stools ◽

Human Nerve

ABSTRACTTranslocation across intestinal epithelial cells is an established pathogenic feature of the zoonotic bacterial speciesCampylobacter jejuni. The number ofC. jejunivirulence factors known to be involved in translocation is limited. In the present study, we investigated whether sialylation ofC. jejunilipooligosaccharide (LOS) structures, generating human nerve ganglioside mimics, is important for intestinal epithelial translocation. We here show thatC. jejuniisolates expressing ganglioside-like LOS bound in larger numbers to the Caco-2 intestinal epithelial cells thanC. jejuniisolates lacking such structures. Next, we found that ganglioside-like LOS facilitated endocytosis of bacteria into Caco-2 cells, as visualized by quantitative microscopy using the early and late endosomal markers early endosome-associated protein 1 (EEA1), Rab5, and lysosome-associated membrane protein 1 (LAMP-1). This increased endocytosis was associated with larger numbers of surviving and translocating bacteria. Next, we found that two different intestinal epithelial cell lines (Caco-2 and T84) responded with an elevated secretion of the T-cell attractant CXCL10 to infection by ganglioside-like LOS-expressingC. jejuniisolates. We conclude thatC. jejunitranslocation across Caco-2 cells is facilitated by ganglioside-like LOS, which is of clinical relevance sinceC. jejuniganglioside-like LOS-expressing isolates are linked with severe gastroenteritis and bloody stools inC. jejuni-infected patients.

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Intestinal Innate Immunity to Campylobacter jejuni Results in Induction of Bactericidal Human Beta-Defensins 2 and 3

Infection and Immunity ◽

10.1128/iai.73.11.7281-7289.2005 ◽

2005 ◽

Vol 73 (11) ◽

pp. 7281-7289 ◽

Cited By ~ 57

Author(s):

Matthias Zilbauer ◽

Nick Dorrell ◽

Parjeet K. Boughan ◽

Andrew Harris ◽

Brendan W. Wren ◽

...

Keyword(s):

Immune Responses ◽

Antimicrobial Peptides ◽

Campylobacter Jejuni ◽

Bactericidal Effect ◽

Immune Defense ◽

Innate Immune ◽

Intestinal Epithelial ◽

Innate Immune Responses ◽

Innate Defense ◽

Peptide Expression

ABSTRACT Campylobacter jejuni is the most prevalent cause of bacterial diarrhea worldwide. Despite the serious health problems caused by this bacterium, human innate immune responses to C. jejuni infection remain poorly defined. Human β-defensins, a family of epithelial antimicrobial peptides, are a major component of host innate defense at the gastrointestinal mucosal surface. In this study, the effect of two different C. jejuni wild-type strains on human intestinal epithelial innate responses was investigated. Up-regulation of β-defensin gene and peptide expression during infection was observed and recombinant β-defensins were shown to have a direct bactericidal effect against C. jejuni through disruption of cell wall integrity. Further studies using an isogenic capsule-deficient mutant showed that, surprisingly, the absence of the bacterial polysaccharide capsule did not change the innate immune responses induced by C. jejuni or the ability of C. jejuni to survive exposure to recombinant β-defensins. This study suggests a major role for this family of antimicrobial peptides in the innate immune defense against this human pathogen.

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Luminal-Applied Flagellin Is Internalized by Polarized Intestinal Epithelial Cells and Elicits Immune Responses via the TLR5 Dependent Mechanism

PLoS ONE ◽

10.1371/journal.pone.0024869 ◽

2011 ◽

Vol 6 (9) ◽

pp. e24869 ◽

Cited By ~ 10

Author(s):

Tonyia Eaves-Pyles ◽

Heng-Fu Bu ◽

Xiao-di Tan ◽

Yingzi Cong ◽

Jignesh Patel ◽

...

Keyword(s):

Epithelial Cells ◽

Immune Responses ◽

Intestinal Epithelial Cells ◽

Intestinal Epithelial ◽

Dependent Mechanism

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A σ28-Regulated Nonflagella Gene Contributes to Virulence of Campylobacter jejuni 81-176

Infection and Immunity ◽

10.1128/iai.74.1.769-772.2006 ◽

2006 ◽

Vol 74 (1) ◽

pp. 769-772 ◽

Cited By ~ 35

Author(s):

Scarlett Goon ◽

Cheryl P. Ewing ◽

Maria Lorenzo ◽

Dawn Pattarini ◽

Gary Majam ◽

...

Keyword(s):

Epithelial Cells ◽

Campylobacter Jejuni ◽

Diarrheal Disease ◽

Intestinal Epithelial Cells ◽

Disease Model ◽

Intestinal Epithelial ◽

Model Expression

ABSTRACT A Campylobacter jejuni 81-176 mutant in Cj0977 was fully motile but reduced >3 logs compared to the parent in invasion of intestinal epithelial cells in vitro. The mutant was also attenuated in a ferret diarrheal disease model. Expression of Cj0977 protein was dependent on a minimal flagella structure.

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