1
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Ra YE, Bang YJ. Balancing Act of the Intestinal Antimicrobial Proteins on Gut Microbiota and Health. J Microbiol 2024; 62:167-179. [PMID: 38630349 DOI: 10.1007/s12275-024-00122-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2023] [Revised: 02/15/2024] [Accepted: 02/16/2024] [Indexed: 05/15/2024]
Abstract
The human gut houses a diverse and dynamic microbiome critical for digestion, metabolism, and immune development, exerting profound effects on human health. However, these microorganisms pose a potential threat by breaching the gut barrier, entering host tissues, and triggering infections, uncontrolled inflammation, and even sepsis. The intestinal epithelial cells form the primary defense, acting as a frontline barrier against microbial invasion. Antimicrobial proteins (AMPs), produced by these cells, serve as innate immune effectors that regulate the gut microbiome by directly killing or inhibiting microbes. Abnormal AMP production, whether insufficient or excessive, can disturb the microbiome equilibrium, contributing to various intestinal diseases. This review delves into the complex interactions between AMPs and the gut microbiota and sheds light on the role of AMPs in governing host-microbiota interactions. We discuss the function and mechanisms of action of AMPs, their regulation by the gut microbiota, microbial evasion strategies, and the consequences of AMP dysregulation in disease. Understanding these complex interactions between AMPs and the gut microbiota is crucial for developing strategies to enhance immune responses and combat infections within the gut microbiota. Ongoing research continues to uncover novel aspects of this intricate relationship, deepening our understanding of the factors shaping gut health. This knowledge has the potential to revolutionize therapeutic interventions, offering enhanced treatments for a wide range of gut-related diseases.
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Affiliation(s)
- Ye Eun Ra
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, 03080, Republic of Korea
| | - Ye-Ji Bang
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, 03080, Republic of Korea.
- Department of Microbiology and Immunology, Seoul National University College of Medicine, Seoul, 03080, Republic of Korea.
- Institute of Infectious Diseases, Seoul National University College of Medicine, Seoul, 03080, Republic of Korea.
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2
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Brabec T, Vobořil M, Schierová D, Valter E, Šplíchalová I, Dobeš J, Březina J, Dobešová M, Aidarova A, Jakubec M, Manning J, Blumberg R, Waisman A, Kolář M, Kubovčiak J, Šrůtková D, Hudcovic T, Schwarzer M, Froňková E, Pinkasová T, Jabandžiev P, Filipp D. IL-17-driven induction of Paneth cell antimicrobial functions protects the host from microbiota dysbiosis and inflammation in the ileum. Mucosal Immunol 2023; 16:373-385. [PMID: 36739089 DOI: 10.1016/j.mucimm.2023.01.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 01/11/2023] [Indexed: 02/05/2023]
Abstract
Interleukin (IL)-17 protects epithelial barriers by inducing the secretion of antimicrobial peptides. However, the effect of IL-17 on Paneth cells (PCs), the major producers of antimicrobial peptides in the small intestine, is unclear. Here, we show that the targeted ablation of the IL-17 receptor (IL-17R) in PCs disrupts their antimicrobial functions and decreases the frequency of ileal PCs. These changes become more pronounced after colonization with IL-17 inducing segmented filamentous bacteria. Mice with PCs that lack IL-17R show an increased inflammatory transcriptional profile in the ileum along with the severity of experimentally induced ileitis. These changes are associated with a decrease in the diversity of gut microbiota that induces a severe ileum pathology upon transfer to genetically susceptible mice, which can be prevented by the systemic administration of IL-17a/f in microbiota recipients. In an exploratory analysis of a small cohort of pediatric patients with Crohn's disease, we have found that a portion of these patients exhibits a low number of lysozyme-expressing ileal PCs and a high ileitis severity score, resembling the phenotype of mice with IL-17R-deficient PCs. Our study identifies IL-17R-dependent signaling in PCs as an important mechanism that maintains ileal homeostasis through the prevention of dysbiosis.
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Affiliation(s)
- Tomáš Brabec
- Laboratory of Immunobiology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic; Department of Cell Biology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Matouš Vobořil
- Laboratory of Immunobiology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Dagmar Schierová
- Laboratory of Anaerobic Microbiology, Institute of Animal Physiology and Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Evgeny Valter
- Laboratory of Immunobiology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Iva Šplíchalová
- Laboratory of Immunobiology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Jan Dobeš
- Department of Cell Biology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Jiří Březina
- Laboratory of Immunobiology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Martina Dobešová
- Laboratory of Immunobiology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Aigerim Aidarova
- Laboratory of Immunobiology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Martin Jakubec
- Laboratory of Immunobiology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Jasper Manning
- Laboratory of Immunobiology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Richard Blumberg
- Brigham and Women's Hospital, Gastroenterology Division, Boston, USA
| | - Ari Waisman
- Institute for Molecular Medicine, University Medical Center of the Johannes Gutenberg University of Mainz, Mainz, Germany
| | - Michal Kolář
- Laboratory of Genomics and Bioinformatics, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Jan Kubovčiak
- Laboratory of Genomics and Bioinformatics, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Dagmar Šrůtková
- Laboratory of Gnotobiology, Institute of Microbiology of the Czech Academy of Sciences, Novy Hradek, Czech Republic
| | - Tomáš Hudcovic
- Laboratory of Gnotobiology, Institute of Microbiology of the Czech Academy of Sciences, Novy Hradek, Czech Republic
| | - Martin Schwarzer
- Laboratory of Gnotobiology, Institute of Microbiology of the Czech Academy of Sciences, Novy Hradek, Czech Republic
| | - Eva Froňková
- Department of Paediatric Haematology and Oncology, Second Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Tereza Pinkasová
- Department of Pediatric, University Hospital Brno, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Petr Jabandžiev
- Department of Pediatric, University Hospital Brno, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Dominik Filipp
- Laboratory of Immunobiology, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic.
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3
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Wang R, Cao S, Bashir MEH, Hesser LA, Su Y, Hong SMC, Thompson A, Culleen E, Sabados M, Dylla NP, Campbell E, Bao R, Nonnecke EB, Bevins CL, Wilson DS, Hubbell JA, Nagler CR. Treatment of peanut allergy and colitis in mice via the intestinal release of butyrate from polymeric micelles. Nat Biomed Eng 2023; 7:38-55. [PMID: 36550307 PMCID: PMC9870785 DOI: 10.1038/s41551-022-00972-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Accepted: 10/26/2022] [Indexed: 12/24/2022]
Abstract
The microbiome modulates host immunity and aids the maintenance of tolerance in the gut, where microbial and food-derived antigens are abundant. Yet modern dietary factors and the excessive use of antibiotics have contributed to the rising incidence of food allergies, inflammatory bowel disease and other non-communicable chronic diseases associated with the depletion of beneficial taxa, including butyrate-producing Clostridia. Here we show that intragastrically delivered neutral and negatively charged polymeric micelles releasing butyrate in different regions of the intestinal tract restore barrier-protective responses in mouse models of colitis and of peanut allergy. Treatment with the butyrate-releasing micelles increased the abundance of butyrate-producing taxa in Clostridium cluster XIVa, protected mice from an anaphylactic reaction to a peanut challenge and reduced disease severity in a T-cell-transfer model of colitis. By restoring microbial and mucosal homoeostasis, butyrate-releasing micelles may function as an antigen-agnostic approach for the treatment of allergic and inflammatory diseases.
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Affiliation(s)
- Ruyi Wang
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, USA
- Department of Chemistry, University of Chicago, Chicago, IL, USA
| | - Shijie Cao
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, USA
| | | | - Lauren A Hesser
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, USA
| | - Yanlin Su
- Biological Sciences Division, University of Chicago, Chicago, IL, USA
- Department of Pathology, University of Chicago, Chicago, IL, USA
| | - Sung Min Choi Hong
- Biological Sciences Division, University of Chicago, Chicago, IL, USA
- Department of Pathology, University of Chicago, Chicago, IL, USA
| | - Andrew Thompson
- Biological Sciences Division, University of Chicago, Chicago, IL, USA
- Department of Pathology, University of Chicago, Chicago, IL, USA
| | - Elliot Culleen
- Biological Sciences Division, University of Chicago, Chicago, IL, USA
- Department of Pathology, University of Chicago, Chicago, IL, USA
| | - Matthew Sabados
- Biological Sciences Division, University of Chicago, Chicago, IL, USA
| | - Nicholas P Dylla
- Duchossois Family Institute, University of Chicago, Chicago, IL, USA
| | - Evelyn Campbell
- Biological Sciences Division, University of Chicago, Chicago, IL, USA
- Committee on Microbiology, University of Chicago, Chicago, IL, USA
| | - Riyue Bao
- Department of Pediatrics, University of Chicago, Chicago, IL, USA
- UPMC Hillman Cancer Center, Pittsburgh, PA, USA
- Department of Medicine, University of Pittsburgh, Pittsburgh, PA, USA
| | - Eric B Nonnecke
- Department of Microbiology and Immunology, School of Medicine, University of California, Davis, CA, USA
| | - Charles L Bevins
- Department of Microbiology and Immunology, School of Medicine, University of California, Davis, CA, USA
| | - D Scott Wilson
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, USA
- Department of Biomedical Engineering, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Jeffrey A Hubbell
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, USA.
- Committee on Immunology, University of Chicago, Chicago, IL, USA.
- Committee on Cancer Biology, University of Chicago, Chicago, IL, USA.
| | - Cathryn R Nagler
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL, USA.
- Biological Sciences Division, University of Chicago, Chicago, IL, USA.
- Department of Pathology, University of Chicago, Chicago, IL, USA.
- Committee on Immunology, University of Chicago, Chicago, IL, USA.
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4
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Xia X, Xie Y, Gong Y, Zhan M, He Y, Liang X, Jin Y, Yang Y, Ding W. Electroacupuncture promoted intestinal defensins and rescued the dysbiotic cecal microbiota of high-fat diet-induced obese mice. Life Sci 2022; 309:120961. [PMID: 36116529 DOI: 10.1016/j.lfs.2022.120961] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2022] [Revised: 09/08/2022] [Accepted: 09/10/2022] [Indexed: 10/31/2022]
Abstract
Obesity is currently one of the most important challenges to public health worldwide. Acupuncture has been widely used to treat obesity. However, whether acupuncture regulates intestinal innate immunity via intestinal microbiota against obesity remains to be elucidated. In this study, electroacupuncture (EA) effectively reduced body weight and fat accumulation in obese mice persistently fed a high-fat diet. Full-length 16S rDNA sequencing showed dysbiotic microbiota in the cecum of obese mice. The composition and function of the cecal microbiota of obese mice were markedly restored after EA treatment. After 21 d of EA intervention, the expression of defensin alpha 5 (Defa5) was restored to healthy controls, whereas fat digestion and absorption genes including fabp1 were markedly decreased in the jejunum of obese mice. The Defa5 levels were positively correlated with the family Lachnospiraceae and negatively correlated with obesity indexes. EA also reduced tissue inflammation, ameliorated misaligned glucose tolerance, and inhibited key genes for intestinal lipid absorption. In summary, EA exerted an anti-obesity effect by promoting intestinal defensins, rescuing dysbiotic cecal microbiota, and reducing lipid absorption in a synergistic mode. We present for the first time the key role of alpha defensins in the relationship between gut microbiota and disease during electroacupuncture treatment of obesity. The mucosal innate immunity seems to have a stronger ability to shape the microbiota than dietary factors.
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Affiliation(s)
- Xiuwen Xia
- Chengdu University of Traditional Chinese Medicine, Wenjiang District, Chengdu, Sichuan, China.
| | - Ya Xie
- Chengdu University of Traditional Chinese Medicine, Wenjiang District, Chengdu, Sichuan, China
| | - Yanju Gong
- Chengdu University of Traditional Chinese Medicine, Wenjiang District, Chengdu, Sichuan, China
| | - Meng Zhan
- Chengdu University of Traditional Chinese Medicine, Wenjiang District, Chengdu, Sichuan, China
| | - Yan He
- Chengdu University of Traditional Chinese Medicine, Wenjiang District, Chengdu, Sichuan, China
| | - Xinyu Liang
- Chengdu University of Traditional Chinese Medicine, Wenjiang District, Chengdu, Sichuan, China
| | - Yue Jin
- Chengdu University of Traditional Chinese Medicine, Wenjiang District, Chengdu, Sichuan, China
| | - Youjun Yang
- Chengdu University of Traditional Chinese Medicine, Wenjiang District, Chengdu, Sichuan, China
| | - Weijun Ding
- Chengdu University of Traditional Chinese Medicine, Wenjiang District, Chengdu, Sichuan, China.
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5
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Nonnecke EB, Castillo PA, Akahoshi DT, Goley SM, Bevins CL, Lönnerdal B. Characterization of an intelectin-1 ( Itln1) knockout mouse model. Front Immunol 2022; 13:894649. [PMID: 36072603 PMCID: PMC9441953 DOI: 10.3389/fimmu.2022.894649] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Accepted: 07/28/2022] [Indexed: 01/26/2023] Open
Abstract
Intelectins are carbohydrate-binding proteins implicated in innate immunity and highly conserved across chordate evolution, including both ascidians and humans. Human intelectin-1 (ITLN1) is highly abundant within the intestinal mucosa and binds microbial but not host glycans. Genome-wide association studies identified SNPs in ITLN1 that are linked to susceptibility for Crohn's disease. Moreover, ITLN1 has been implicated in the pathophysiology of obesity and associated metabolic disease. To gain insight on biological activities of human ITLN1 in vivo, we developed a C57BL/6 mouse model genetically targeting the gene encoding the functional mouse ortholog. In wild-type C57BL/6 mice, both mRNA and protein analysis showed high expression of Itln1 in the small intestine, but manifold lower levels in colon and other extraintestinal tissues. Whereas intestinal expression of human ITLN1 localizes to goblet cells, our data confirm that mouse Itln1 is expressed in Paneth cells. Compared to wild-type littermate controls, mice homozygous for the Itln1 hypomorphic trapping allele had reduced expression levels of Itln1 expression (~10,000-fold). The knockout mice exhibited increased susceptibility in an acute model of experimentally induced colitis with 2% w/v dextran sulfate sodium (DSS). In a model of chronic colitis using a lower dose of DSS (1.5% w/v), which enabled a detailed view of disease activity across a protracted period, no differences were observed in body weight, fecal texture, hemoccult scores, food/water intake, or colon length at necropsy, but there was a statistically significant genotype over time effect for the combined fecal scores of disease activity. In model of diet-induced obesity, using two western-style diets, which varied in amounts of sugar (as sucrose) and saturated fat (as lard), mice with Itln1 expression ablated showed no increased susceptibility, in terms of weight gain, food intake, plasma markers of obesity compared to wildtype littermates. While the mouse genetic knockout model for Itln1 holds promise for elucidating physiological function(s) for mammalian intelectins, results reported here suggest that Itln1, a Paneth cell product in C57BL/6 mice, likely plays a minor role in the pathophysiology of chemically induced colitis or diet-induced obesity.
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Affiliation(s)
- Eric B. Nonnecke
- Department of Microbiology and Immunology, School of Medicine, University of California, Davis, Davis, CA, United States,*Correspondence: Eric B. Nonnecke, ; Charles L. Bevins,
| | - Patricia A. Castillo
- Department of Microbiology and Immunology, School of Medicine, University of California, Davis, Davis, CA, United States
| | - Douglas T. Akahoshi
- Department of Microbiology and Immunology, School of Medicine, University of California, Davis, Davis, CA, United States
| | - Stephanie M. Goley
- Department of Nutrition, University of California, Davis, Davis, CA, United States
| | - Charles L. Bevins
- Department of Microbiology and Immunology, School of Medicine, University of California, Davis, Davis, CA, United States,*Correspondence: Eric B. Nonnecke, ; Charles L. Bevins,
| | - Bo Lönnerdal
- Department of Nutrition, University of California, Davis, Davis, CA, United States
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6
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Toxoplasma gondii Infection Decreases Intestinal 5-Lipoxygenase Expression, while Exogenous LTB 4 Controls Parasite Growth. Infect Immun 2022; 90:e0002922. [PMID: 35658510 DOI: 10.1128/iai.00029-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
5-Lipoxygenase (5-LO) is an enzyme required for the production of leukotrienes and lipoxins and interferes with parasitic infections. In vitro, Toxoplasma gondii inhibits leukotriene B4 (LTB4) production, and mice deficient in 5-LO are highly susceptible to infection. The aim of this study was to investigate the effects of the pharmacological inhibition of the 5-LO pathway and exogenous LTB4 supplementation during experimental toxoplasmosis. For this purpose, susceptible C57BL/6 mice were orally infected with T. gondii and treated with LTB4 or MK886 (a selective leukotriene inhibitor through inhibition of 5-LO-activating protein [FLAP]). The parasitism, histology, and immunological parameters were analyzed. The infection decreased 5-LO expression in the small intestine, and treatment with MK886 reinforced this reduction during infection; in addition, MK886-treated infected mice presented higher intestinal parasitism, which was associated with lower local interleukin-6 (IL-6), interferon gamma (IFN-γ), and tumor necrosis factor (TNF) production. In contrast, treatment with LTB4 controlled parasite replication in the small intestine, liver, and lung and decreased pulmonary pathology. Interestingly, treatment with LTB4 also preserved the number of Paneth cells and increased α-defensins expression and IgA levels in the small intestine of infected mice. Altogether, these data demonstrated that T. gondii infection is associated with a decrease in 5-LO expression, and on the other hand, treatment with the 5-LO pathway product LTB4 resulted in better control of parasite growth in the organs, adding to the knowledge about the pathogenesis of T. gondii infection.
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7
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A potent HNF4α agonist reveals that HNF4α controls genes important in inflammatory bowel disease and Paneth cells. PLoS One 2022; 17:e0266066. [PMID: 35385524 PMCID: PMC8985954 DOI: 10.1371/journal.pone.0266066] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 03/11/2022] [Indexed: 11/19/2022] Open
Abstract
HNF4α has been implicated in IBD through a number of genome-wide association studies. Recently, we developed potent HNF4α agonists, including N-trans caffeoyltyramine (NCT). NCT was identified by structural similarity to previously the previously identified but weak HNF4α agonists alverine and benfluorex. Here, we administered NCT to mice fed a high fat diet, with the goal of studying the role of HNF4α in obesity-related diseases. Intestines from NCT-treated mice were examined by RNA-seq to determine the role of HNF4α in that organ. Surprisingly, the major classes of genes altered by HNF4α were involved in IBD and Paneth cell biology. Multiple genes downregulated in IBD were induced by NCT. Paneth cells identified by lysozyme expression were reduced in high fat fed mice. NCT reversed the effect of high fat diet on Paneth cells, with multiple markers being induced, including a number of defensins, which are critical for Paneth cell function and intestinal barrier integrity. NCT upregulated genes that play important role in IBD and that are downregulated in that disease. It reversed the loss of Paneth cell markers that occurred in high fat diet fed mice. These data suggest that HNF4α could be a therapeutic target for IBD and that the agonists that we have identified could be candidate therapeutics.
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8
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Nonnecke EB, Castillo PA, Johansson MEV, Hollox EJ, Shen B, Lönnerdal B, Bevins CL. Human intelectin-2 (ITLN2) is selectively expressed by secretory Paneth cells. FASEB J 2022; 36:e22200. [PMID: 35182405 PMCID: PMC9262044 DOI: 10.1096/fj.202101870r] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 01/20/2022] [Accepted: 01/26/2022] [Indexed: 01/04/2023]
Abstract
Intelectins (intestinal lectins) are highly conserved across chordate evolution and have been implicated in various human diseases, including Crohn's disease (CD). The human genome encodes two intelectin genes, intelectin-1 (ITLN1) and intelectin-2 (ITLN2). Other than its high sequence similarity with ITLN1, little is known about ITLN2. To address this void in knowledge, we report that ITLN2 exhibits discrete, yet notable differences from ITLN1 in primary structure, including a unique amino terminus, as well as changes in amino acid residues associated with the glycan-binding activity of ITLN1. We identified that ITLN2 is a highly abundant Paneth cell-specific product, which localizes to secretory granules, and is expressed as a multimeric protein in the small intestine. In surgical specimens of ileal CD, ITLN2 mRNA levels were reduced approximately five-fold compared to control specimens. The ileal expression of ITLN2 was unaffected by previously reported disease-associated variants in ITLN2 and CD-associated variants in neighboring ITLN1 as well as NOD2 and ATG16L1. ITLN2 mRNA expression was undetectable in control colon tissue; however, in both ulcerative colitis (UC) and colonic CD, metaplastic Paneth cells were found to express ITLN2. Together, the data reported establish the groundwork for understanding ITLN2 function(s) in the intestine, including its possible role in CD.
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Affiliation(s)
- Eric B Nonnecke
- Department of Microbiology and Immunology, School of Medicine, University of California, Davis, Davis, California, USA
| | - Patricia A Castillo
- Department of Microbiology and Immunology, School of Medicine, University of California, Davis, Davis, California, USA
| | - Malin E V Johansson
- Department of Medical Biochemistry and Cell Biology, Institute of Biomedicine, University of Gothenburg, Gothenburg, Sweden
| | - Edward J Hollox
- Department of Genetics and Genome Biology, University of Leicester, Leicester, UK
| | - Bo Shen
- Department of Gastroenterology, Hepatology and Nutrition, Digestive Diseases and Surgery Institute, Cleveland Clinic, Cleveland, Ohio, USA
| | - Bo Lönnerdal
- Department of Nutrition, University of California, Davis, Davis, California, USA
| | - Charles L Bevins
- Department of Microbiology and Immunology, School of Medicine, University of California, Davis, Davis, California, USA
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9
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Rivera CA, Randrian V, Richer W, Gerber-Ferder Y, Delgado MG, Chikina AS, Frede A, Sorini C, Maurin M, Kammoun-Chaari H, Parigi SM, Goudot C, Cabeza-Cabrerizo M, Baulande S, Lameiras S, Guermonprez P, Reis e Sousa C, Lecuit M, Moreau HD, Helft J, Vignjevic DM, Villablanca EJ, Lennon-Duménil AM. Epithelial colonization by gut dendritic cells promotes their functional diversification. Immunity 2022; 55:129-144.e8. [PMID: 34910930 PMCID: PMC8751639 DOI: 10.1016/j.immuni.2021.11.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 08/19/2021] [Accepted: 11/15/2021] [Indexed: 12/23/2022]
Abstract
Dendritic cells (DCs) patrol tissues and transport antigens to lymph nodes to initiate adaptive immune responses. Within tissues, DCs constitute a complex cell population composed of distinct subsets that can exhibit different activation states and functions. How tissue-specific cues orchestrate DC diversification remains elusive. Here, we show that the small intestine included two pools of cDC2s originating from common pre-DC precursors: (1) lamina propria (LP) CD103+CD11b+ cDC2s that were mature-like proinflammatory cells and (2) intraepithelial cDC2s that exhibited an immature-like phenotype as well as tolerogenic properties. These phenotypes resulted from the action of food-derived retinoic acid (ATRA), which enhanced actomyosin contractility and promoted LP cDC2 transmigration into the epithelium. There, cDC2s were imprinted by environmental cues, including ATRA itself and the mucus component Muc2. Hence, by reaching distinct subtissular niches, DCs can exist as immature and mature cells within the same tissue, revealing an additional mechanism of DC functional diversification.
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Affiliation(s)
- Claudia A Rivera
- Institut Curie, INSERM U932, PSL Research University, 75005 Paris, France
| | - Violaine Randrian
- Institut Curie, INSERM U932, PSL Research University, 75005 Paris, France
| | - Wilfrid Richer
- Institut Curie, INSERM U932, PSL Research University, 75005 Paris, France
| | | | | | - Aleksandra S Chikina
- Institut Curie, INSERM U932, PSL Research University, 75005 Paris, France; Institut Curie, CNRS UMR 144, PSL Research University, 75005 Paris, France
| | - Annika Frede
- Immunology and Allergy division, Department of Medicine, Solna, Karolinska Institutet and University Hospital, 17176 Stockholm, Sweden; Center of Molecular Medicine, 17176 Stockholm, Sweden
| | - Chiara Sorini
- Immunology and Allergy division, Department of Medicine, Solna, Karolinska Institutet and University Hospital, 17176 Stockholm, Sweden; Center of Molecular Medicine, 17176 Stockholm, Sweden
| | - Mathieu Maurin
- Institut Curie, INSERM U932, PSL Research University, 75005 Paris, France
| | - Hana Kammoun-Chaari
- Biology of Infection Unit, Institut Pasteur, INSERM U1117, 75015 Paris, France
| | - Sara M Parigi
- Immunology and Allergy division, Department of Medicine, Solna, Karolinska Institutet and University Hospital, 17176 Stockholm, Sweden; Center of Molecular Medicine, 17176 Stockholm, Sweden
| | - Christel Goudot
- Institut Curie, INSERM U932, PSL Research University, 75005 Paris, France
| | | | - Sylvain Baulande
- ICGex Next-Generation Sequencing Platform, Institut Curie, PSL Research University, 75005 Paris, France
| | - Sonia Lameiras
- ICGex Next-Generation Sequencing Platform, Institut Curie, PSL Research University, 75005 Paris, France
| | - Pierre Guermonprez
- Université de Paris, Centre for Inflammation Research, CNRS ERL8252, INSERM1149, Paris, France
| | | | - Marc Lecuit
- Biology of Infection Unit, Institut Pasteur, INSERM U1117, 75015 Paris, France; Université de Paris, Necker-Enfants Malades University Hospital, Department of Infectious Diseases and Tropical Medicine, APHP, Institut Imagine, Paris, France
| | - Hélène D Moreau
- Institut Curie, INSERM U932, PSL Research University, 75005 Paris, France
| | - Julie Helft
- Institut Curie, INSERM U932, PSL Research University, 75005 Paris, France
| | | | - Eduardo J Villablanca
- Immunology and Allergy division, Department of Medicine, Solna, Karolinska Institutet and University Hospital, 17176 Stockholm, Sweden; Center of Molecular Medicine, 17176 Stockholm, Sweden
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10
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Araujo A, Safronova A, Burger E, López-Yglesias A, Giri S, Camanzo ET, Martin AT, Grivennikov S, Yarovinsky F. IFN-γ mediates Paneth cell death via suppression of mTOR. eLife 2021; 10:60478. [PMID: 34633285 PMCID: PMC8570691 DOI: 10.7554/elife.60478] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2020] [Accepted: 10/10/2021] [Indexed: 12/12/2022] Open
Abstract
Paneth cells constitutively produce antimicrobial peptides and growth factors that allow for intestinal homeostasis, host protection, and intestinal stem cell replication. Paneth cells rely heavily on the glycolytic metabolic program, which is in part controlled by the kinase complex Mechanistic target of rapamycin (mTORC1). Yet, little is known about mTOR importance in Paneth cell integrity under steady-state and inflammatory conditions. Our results demonstrate that IFN-γ, a crucial mediator of the intestinal inflammation, acts directly on murine Paneth cells to alter their mitochondrial integrity and membrane potential, resulting in an TORC1-dependent cell death mechanism distinct from canonical cell death pathways including apoptosis, necroptosis, and pyroptosis. These results were established with the purified cytokine and a physiologically relevant common Th1-inducing human parasite Toxoplasma gondii. Given the crucial role for IFN-γ, which is a cytokine frequently associated with the development of inflammatory bowel disease and compromised Paneth cell functions, the identified mechanisms underlying mTORC1-dependent Paneth cell death downstream of IFN-γ may provide promising novel approaches for treating intestinal inflammation.
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Affiliation(s)
- Alessandra Araujo
- Center for Vaccine Biology and Immunology, Department of Microbiology and Immunology, University of Rochester Medical Center, New York, United States
| | - Alexandra Safronova
- Center for Vaccine Biology and Immunology, Department of Microbiology and Immunology, University of Rochester Medical Center, New York, United States
| | - Elise Burger
- Center for Vaccine Biology and Immunology, Department of Microbiology and Immunology, University of Rochester Medical Center, New York, United States
| | - Américo López-Yglesias
- Center for Vaccine Biology and Immunology, Department of Microbiology and Immunology, University of Rochester Medical Center, New York, United States
| | - Shilpi Giri
- Center for Vaccine Biology and Immunology, Department of Microbiology and Immunology, University of Rochester Medical Center, New York, United States
| | - Ellie T Camanzo
- Center for Vaccine Biology and Immunology, Department of Microbiology and Immunology, University of Rochester Medical Center, New York, United States
| | - Andrew T Martin
- Center for Vaccine Biology and Immunology, Department of Microbiology and Immunology, University of Rochester Medical Center, New York, United States
| | - Sergei Grivennikov
- Department of Medicine and Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, United States.,Cancer Prevention and Control Program, Fox Chase Cancer Center, Philadelphia, United States
| | - Felix Yarovinsky
- Center for Vaccine Biology and Immunology, Department of Microbiology and Immunology, University of Rochester Medical Center, New York, United States
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11
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Extensive variation in the intelectin gene family in laboratory and wild mouse strains. Sci Rep 2021; 11:15548. [PMID: 34330944 PMCID: PMC8324875 DOI: 10.1038/s41598-021-94679-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 07/13/2021] [Indexed: 12/30/2022] Open
Abstract
Intelectins are a family of multimeric secreted proteins that bind microbe-specific glycans. Both genetic and functional studies have suggested that intelectins have an important role in innate immunity and are involved in the etiology of various human diseases, including inflammatory bowel disease. Experiments investigating the role of intelectins in human disease using mouse models are limited by the fact that there is not a clear one-to-one relationship between intelectin genes in humans and mice, and that the number of intelectin genes varies between different mouse strains. In this study we show by gene sequence and gene expression analysis that human intelectin-1 (ITLN1) has multiple orthologues in mice, including a functional homologue Itln1; however, human intelectin-2 has no such orthologue or homologue. We confirm that all sub-strains of the C57 mouse strain have a large deletion resulting in retention of only one intelectin gene, Itln1. The majority of laboratory strains have a full complement of six intelectin genes, except CAST, SPRET, SKIVE, MOLF and PANCEVO strains, which are derived from different mouse species/subspecies and encode different complements of intelectin genes. In wild mice, intelectin deletions are polymorphic in Mus musculus castaneus and Mus musculus domesticus. Further sequence analysis shows that Itln3 and Itln5 are polymorphic pseudogenes due to premature truncating mutations, and that mouse Itln1 has undergone recent adaptive evolution. Taken together, our study shows extensive diversity in intelectin genes in both laboratory and wild-mice, suggesting a pattern of birth-and-death evolution. In addition, our data provide a foundation for further experimental investigation of the role of intelectins in disease.
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12
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Secretory Sorcery: Paneth Cell Control of Intestinal Repair and Homeostasis. Cell Mol Gastroenterol Hepatol 2021; 12:1239-1250. [PMID: 34153524 PMCID: PMC8446800 DOI: 10.1016/j.jcmgh.2021.06.006] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 06/08/2021] [Accepted: 06/09/2021] [Indexed: 12/18/2022]
Abstract
Paneth cells are professional secretory cells that classically play a role in the innate immune system by secreting antimicrobial factors into the lumen to control enteric bacteria. In this role, Paneth cells are able to sense cues from luminal bacteria and respond by changing production of these factors to protect the epithelial barrier. Paneth cells rely on autophagy to regulate their secretory capability and capacity. Disruption of this pathway through mutation of genes, such as Atg16L1, results in decreased Paneth cell function, dysregulated enteric microbiota, decreased barrier integrity, and increased risk of diseases such as Crohn's disease in humans. Upon differentiation Paneth cells migrate downward and intercalate among active intestinal stem cells at the base of small intestinal crypts. This localization puts them in a unique position to interact with active intestinal stem cells, and recent work shows that Paneth cells play a critical role in influencing the intestinal stem cell niche. This review discusses the numerous ways Paneth cells can influence intestinal stem cells and their niche. We also highlight the ways in which Paneth cells can alter cells and other organ systems.
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13
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Nonnecke EB, Castillo PA, Dugan AE, Almalki F, Underwood MA, De La Motte CA, Yuan W, Lu W, Shen B, Johansson MEV, Kiessling LL, Hollox EJ, Lönnerdal B, Bevins CL. Human intelectin-1 (ITLN1) genetic variation and intestinal expression. Sci Rep 2021; 11:12889. [PMID: 34145348 PMCID: PMC8213764 DOI: 10.1038/s41598-021-92198-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 06/07/2021] [Indexed: 12/13/2022] Open
Abstract
Intelectins are ancient carbohydrate binding proteins, spanning chordate evolution and implicated in multiple human diseases. Previous GWAS have linked SNPs in ITLN1 (also known as omentin) with susceptibility to Crohn's disease (CD); however, analysis of possible functional significance of SNPs at this locus is lacking. Using the Ensembl database, pairwise linkage disequilibrium (LD) analyses indicated that several disease-associated SNPs at the ITLN1 locus, including SNPs in CD244 and Ly9, were in LD. The alleles comprising the risk haplotype are the major alleles in European (67%), but minor alleles in African superpopulations. Neither ITLN1 mRNA nor protein abundance in intestinal tissue, which we confirm as goblet-cell derived, was altered in the CD samples overall nor when samples were analyzed according to genotype. Moreover, the missense variant V109D does not influence ITLN1 glycan binding to the glycan β-D-galactofuranose or protein-protein oligomerization. Taken together, our data are an important step in defining the role(s) of the CD-risk haplotype by determining that risk is unlikely to be due to changes in ITLN1 carbohydrate recognition, protein oligomerization, or expression levels in intestinal mucosa. Our findings suggest that the relationship between the genomic data and disease arises from changes in CD244 or Ly9 biology, differences in ITLN1 expression in other tissues, or an alteration in ITLN1 interaction with other proteins.
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Affiliation(s)
- Eric B Nonnecke
- Department of Microbiology and Immunology, School of Medicine, University of California, Davis, Davis, CA, 95616, USA.
| | - Patricia A Castillo
- Department of Microbiology and Immunology, School of Medicine, University of California, Davis, Davis, CA, 95616, USA
- Elanco Animal Health, Fort Dodge, IA, 50501, USA
| | - Amanda E Dugan
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Faisal Almalki
- Department of Genetics and Genome Biology, University of Leicester, Leicester, UK
- Medical Laboratories Technology Department, College of Applied Medical Sciences, Taibah University, Almadinah Almunwarah, Saudi Arabia
| | - Mark A Underwood
- Department of Pediatrics, School of Medicine, University of California, Davis, Sacramento, CA, 95817, USA
| | - Carol A De La Motte
- Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH, 44195, USA
| | - Weirong Yuan
- Institute of Human Virology, Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Wuyuan Lu
- Institute of Human Virology, Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
- Fudan University, Shanghai, China
| | - Bo Shen
- Department of Gastroenterology, Hepatology and Nutrition, Digestive Diseases and Surgery Institute, Cleveland Clinic, Cleveland, OH, 44195, USA
- Department of Surgery, Columbia University Vagelos College of Physicians and Surgeons, New York, NY, 10032, USA
| | - Malin E V Johansson
- Institute of Biomedicine, Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Gothenburg, Sweden
| | - Laura L Kiessling
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
- The Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA
| | - Edward J Hollox
- Department of Genetics and Genome Biology, University of Leicester, Leicester, UK
| | - Bo Lönnerdal
- Department of Nutrition, University of California, Davis, Davis, CA, 95616, USA
| | - Charles L Bevins
- Department of Microbiology and Immunology, School of Medicine, University of California, Davis, Davis, CA, 95616, USA.
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14
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Astaxanthin Alleviates Ochratoxin A-Induced Cecum Injury and Inflammation in Mice by Regulating the Diversity of Cecal Microbiota and TLR4/MyD88/NF- κB Signaling Pathway. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2021; 2021:8894491. [PMID: 33505592 PMCID: PMC7806395 DOI: 10.1155/2021/8894491] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 11/10/2020] [Accepted: 12/17/2020] [Indexed: 12/12/2022]
Abstract
Ochratoxin A (OTA) is a common environmental pollutant found in a variety of foods and grains, and excessive OTA consumption causes serious global health effects on animals and humans. Astaxanthin (AST) is a natural carotenoid that has anti-inflammatory, antiapoptotic, immunomodulatory, antitumor, antidiabetes, and other biological activities. The present study is aimed at investigating the effects of AST on OTA-induced cecum injury and its mechanism of action. Eighty C57 mice were randomly divided into four groups, including the control group, OTA group (5 mg/kg body weight), AST group (100 mg/kg body weight), and AST intervention group (100 mg/kg body weight AST+5 mg/kg body weight OTA). It was found that AST decreased the endotoxin content, effectively prevented the shortening of mouse cecum villi, and increased the expression levels of tight junction (TJ) proteins, consisting of occludin, claudin-1, and zonula occludens-1 (ZO-1). AST increased the number of goblet cells, the contents of mucin-2 (MUC2), and defensins (Defa5 and β-pD2) significantly, while the expression of mucin-1 (MUC1) decreased significantly. The 16S rRNA sequencing showed that AST affected the richness and diversity of cecum flora, decreased the proportion of lactobacillus, and also decreased the contents of short-chain fatty acids (SCFAs) (acetate and butyrate). In addition, AST significantly decreased the expression of TLR4, MyD88, and p-p65, while increasing the expression of p65. Meanwhile, the expression of inflammatory factors including TNF-α and INF-γ decreased, while the expression of IL-10 increased. In conclusion, AST reduced OTA-induced cecum injury by regulating the cecum barrier function and TLR4/MyD88/NF-κB signaling pathway.
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15
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Nakamura K, Yokoi Y, Fukaya R, Ohira S, Shinozaki R, Nishida T, Kikuchi M, Ayabe T. Expression and Localization of Paneth Cells and Their α-Defensins in the Small Intestine of Adult Mouse. Front Immunol 2020; 11:570296. [PMID: 33154750 PMCID: PMC7590646 DOI: 10.3389/fimmu.2020.570296] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2020] [Accepted: 09/15/2020] [Indexed: 12/12/2022] Open
Abstract
Paneth cells contribute to intestinal innate immunity by sensing bacteria and secreting α-defensin. In Institute of Cancer Research (ICR) mice, α-defensin termed cryptdin (Crp) in Paneth cells consists of six major isoforms, Crp1 to 6. Despite accumulating evidences that α-defensin functions in controlling the intestinal microbiota, topographical localization of Paneth cells in the small intestine in relation to functions of α-defensin remains to be determined. In this study, we examined the expression level of messenger RNA (mRNA) encoding six Crp-isoforms and Crp immunoreactivities using singly isolated crypts together with bactericidal activities of Paneth cell secretions from isolated crypts of duodenum, jejunum, and ileum. Here we showed that levels of Crp mRNAs in the single crypt ranged from 5 x 103 to 1 x 106 copies per 5 ng RNA. For each Crp isoform, the expression level in ileum was 4 to 50 times higher than that in duodenum and jejunum. Furthermore, immunohistochemical analysis of isolated crypts revealed that the average number of Paneth cell per crypt in the small intestine increased from proximal to distal, three to seven-fold, respectively. Both Crp1 and 4 expressed greater in ileal Paneth cells than those in duodenum or jejunum. Bactericidal activities in secretions of ileal Paneth cell exposed to bacteria were significantly higher than those of duodenum or jejunum. In germ-free mice, Crp expression in each site of the small intestine was attenuated and bactericidal activities released by ileal Paneth cells were decreased compared to those in conventional mice. Taken together, Paneth cells and their α-defensin in adult mouse appeared to be regulated topographically in innate immunity to control intestinal integrity.
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Affiliation(s)
- Kiminori Nakamura
- Innate Immunity Laboratory, Department of Cell Biological Science, Graduate School of Life Science, Hokkaido University, Sapporo, Japan.,Innate Immunity Laboratory, Department of Cell Biological Science, Faculty of Advanced Life Science, Hokkaido University, Sapporo, Japan
| | - Yuki Yokoi
- Innate Immunity Laboratory, Department of Cell Biological Science, Faculty of Advanced Life Science, Hokkaido University, Sapporo, Japan
| | - Rie Fukaya
- Innate Immunity Laboratory, Department of Cell Biological Science, Graduate School of Life Science, Hokkaido University, Sapporo, Japan
| | - Shuya Ohira
- Innate Immunity Laboratory, Department of Cell Biological Science, Graduate School of Life Science, Hokkaido University, Sapporo, Japan
| | - Ryuga Shinozaki
- Innate Immunity Laboratory, Department of Cell Biological Science, Graduate School of Life Science, Hokkaido University, Sapporo, Japan
| | - Takuto Nishida
- Innate Immunity Laboratory, Department of Cell Biological Science, Graduate School of Life Science, Hokkaido University, Sapporo, Japan
| | - Mani Kikuchi
- Innate Immunity Laboratory, Department of Cell Biological Science, Faculty of Advanced Life Science, Hokkaido University, Sapporo, Japan
| | - Tokiyoshi Ayabe
- Innate Immunity Laboratory, Department of Cell Biological Science, Graduate School of Life Science, Hokkaido University, Sapporo, Japan.,Innate Immunity Laboratory, Department of Cell Biological Science, Faculty of Advanced Life Science, Hokkaido University, Sapporo, Japan
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16
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Puértolas-Balint F, Schroeder BO. Does an Apple a Day Also Keep the Microbes Away? The Interplay Between Diet, Microbiota, and Host Defense Peptides at the Intestinal Mucosal Barrier. Front Immunol 2020; 11:1164. [PMID: 32655555 PMCID: PMC7325984 DOI: 10.3389/fimmu.2020.01164] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 05/12/2020] [Indexed: 12/13/2022] Open
Abstract
A crucial mechanism of intestinal defense includes the production and secretion of host defense peptides (HDPs). HDPs control pathogens and commensals at the intestinal interface by direct killing, by sequestering vital ions, or by causing bacterial cells to aggregate in the mucus layer. Accordingly, the combined activity of various HDPs neutralizes gut bacteria before reaching the mucosa and thus helps to maintain the homeostatic balance between the host and its microbes at the mucosal barrier. Defects in the mucosal barrier have been associated with various diseases that are on the rise in the Western world. These include metabolic diseases, such as obesity and type 2 diabetes, and inflammatory intestinal disorders, including ulcerative colitis and Crohn's disease, the two major entities of inflammatory bowel disease. While the etiology of these diseases is multifactorial, highly processed Western-style diet (WSD) that is rich in carbohydrates and fat and low in dietary fiber content, is considered to be a contributing lifestyle factor. As such, WSD does not only profoundly affect the resident microbes in the intestine, but can also directly alter HDP function, thereby potentially contributing to intestinal mucosal barrier dysfunction. In this review we aim to decipher the complex interaction between diet, microbiota, and HDPs. We discuss how HDP expression can be modulated by specific microbes and their metabolites as well as by dietary factors, including fibers, lipids, polyphenols and vitamins. We identify several dietary compounds that lead to reduced HDP function, but also factors that stimulate HDP production in the intestine. Furthermore, we argue that the effect of HDPs against commensal bacteria has been understudied when compared to pathogens, and that local environmental conditions also need to be considered. In addition, we discuss the known molecular mechanisms behind HDP modulation. We believe that a better understanding of the diet-microbiota-HDP interdependence will provide insights into factors underlying modern diseases and will help to identify potential dietary interventions or probiotic supplementation that can promote HDP-mediated intestinal barrier function in the Western gut.
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Affiliation(s)
- Fabiola Puértolas-Balint
- Laboratory for Molecular Infection Medicine Sweden (MIMS) -The Nordic EMBL Partnership for Molecular Medicine, Umeå University, Umeå, Sweden.,Department of Molecular Biology, Umeå University, Umeå, Sweden
| | - Bjoern O Schroeder
- Laboratory for Molecular Infection Medicine Sweden (MIMS) -The Nordic EMBL Partnership for Molecular Medicine, Umeå University, Umeå, Sweden.,Department of Molecular Biology, Umeå University, Umeå, Sweden
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