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Ignacio A, Czyz S, McCoy KD. Early life microbiome influences on development of the mucosal innate immune system. Semin Immunol 2024; 73:101885. [PMID: 38788491 DOI: 10.1016/j.smim.2024.101885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 05/11/2024] [Accepted: 05/16/2024] [Indexed: 05/26/2024]
Abstract
The gut microbiota is well known to possess immunomodulatory capacities, influencing a multitude of cellular signalling pathways to maintain host homeostasis. Although the formation of the immune system initiates before birth in a sterile environment, an emerging body of literature indicates that the neonatal immune system is influenced by a first wave of external stimuli that includes signals from the maternal microbiota. A second wave of stimulus begins after birth and must be tightly regulated during the neonatal period when colonization of the host occurs concomitantly with the maturation of the immune system, requiring a fine adjustment between establishing tolerance towards the commensal microbiota and preserving inflammatory responses against pathogenic invaders. Besides integrating cues from commensal microbes, the neonatal immune system must also regulate responses triggered by other environmental signals, such as dietary antigens, which become more complex with the introduction of solid food during the weaning period. This "window of opportunity" in early life is thought to be crucial for the proper development of the immune system, setting the tone of subsequent immune responses in adulthood and modulating the risk of developing chronic and metabolic inflammatory diseases. Here we review the importance of host-microbiota interactions for the development and maturation of the immune system, particularly in the early-life period, highlighting the known mechanisms involved in such communication. This discussion is focused on recent data demonstrating microbiota-mediated education of innate immune cells and its role in the development of lymphoid tissues.
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Affiliation(s)
- Aline Ignacio
- Department of Physiology and Pharmacology, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Sonia Czyz
- Department of Physiology and Pharmacology, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Kathy D McCoy
- Department of Physiology and Pharmacology, Snyder Institute for Chronic Diseases, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.
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2
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Serafini N, Di Santo JP. Group 3 innate lymphoid cells: A trained Gutkeeper. Immunol Rev 2024; 323:126-137. [PMID: 38491842 DOI: 10.1111/imr.13322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2024]
Abstract
Group 3 innate lymphoid cells (ILC3s) are tissue-resident immune lymphocytes that critically regulate intestinal homeostasis, organogenesis, and immunity. ILC3s possess the capacity to "sense" the inflammatory environment within tissues, especially in the context of pathogen challenges that imprints durable non-antigen-specific changes in ILC3 function. As such, ILC3s become a new actor in the emerging field of trained innate immunity. Here, we summarize recent discoveries regarding ILC3 responses to bacterial challenges and the role these encounters play in triggering trained innate immunity. We further discuss how signaling events throughout ILC3 ontogeny potentially control the development and function of trained ILC3s. Finally, we highlight the open questions surrounding ILC3 "training" the answers to which may reveal new insights into innate immunity. Understanding the fundamental concepts behind trained innate immunity could potentially lead to the development of new strategies for improving immunity-based modulation therapies for inflammation, infectious diseases, and cancer.
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Affiliation(s)
- Nicolas Serafini
- Innate Immunity Unit, Institut Pasteur, Université Paris Cité, Inserm U1223, Paris, France
| | - James P Di Santo
- Innate Immunity Unit, Institut Pasteur, Université Paris Cité, Inserm U1223, Paris, France
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3
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López-Fandiño R, Molina E, Lozano-Ojalvo D. Intestinal factors promoting the development of RORγt + cells and oral tolerance. Front Immunol 2023; 14:1294292. [PMID: 37936708 PMCID: PMC10626553 DOI: 10.3389/fimmu.2023.1294292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 10/09/2023] [Indexed: 11/09/2023] Open
Abstract
The gastrointestinal tract has to harmonize the two seemingly opposite functions of fulfilling nutritional needs and avoiding the entry of pathogens, toxins and agents that can cause physical damage. This balance requires a constant adjustment of absorptive and defending functions by sensing environmental changes or noxious substances and initiating adaptive or protective mechanisms against them through a complex network of receptors integrated with the central nervous system that communicate with cells of the innate and adaptive immune system. Effective homeostatic processes at barrier sites take the responsibility for oral tolerance, which protects from adverse reactions to food that cause allergic diseases. During a very specific time interval in early life, the establishment of a stable microbiota in the large intestine is sufficient to prevent pathological events in adulthood towards a much larger bacterial community and provide tolerance towards diverse food antigens encountered later in life. The beneficial effects of the microbiome are mainly exerted by innate and adaptive cells that express the transcription factor RORγt, in whose generation, mediated by different bacterial metabolites, retinoic acid signalling plays a predominant role. In addition, recent investigations indicate that food antigens also contribute, analogously to microbial-derived signals, to educating innate immune cells and instructing the development and function of RORγt+ cells in the small intestine, complementing and expanding the tolerogenic effect of the microbiome in the colon. This review addresses the mechanisms through which microbiota-produced metabolites and dietary antigens maintain intestinal homeostasis, highlighting the complementarity and redundancy between their functions.
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Affiliation(s)
- Rosina López-Fandiño
- Instituto de Investigación en Ciencias de la Alimentación (CIAL), CSIC-UAM, Madrid, Spain
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4
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Koprivica I, Stanisavljević S, Mićanović D, Jevtić B, Stojanović I, Miljković Đ. ILC3: a case of conflicted identity. Front Immunol 2023; 14:1271699. [PMID: 37915588 PMCID: PMC10616800 DOI: 10.3389/fimmu.2023.1271699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2023] [Accepted: 10/02/2023] [Indexed: 11/03/2023] Open
Abstract
Innate lymphoid cells type 3 (ILC3s) are the first line sentinels at the mucous tissues, where they contribute to the homeostatic immune response in a major way. Also, they have been increasingly appreciated as important modulators of chronic inflammatory and autoimmune responses, both locally and systemically. The proper identification of ILC3 is of utmost importance for meaningful studies on their role in immunity. Flow cytometry is the method of choice for the detection and characterization of ILC3. However, the analysis of ILC3-related papers shows inconsistency in ILC3 phenotypic definition, as different inclusion and exclusion markers are used for their identification. Here, we present these discrepancies in the phenotypic characterization of human and mouse ILC3s. We discuss the pros and cons of using various markers for ILC3 identification. Furthermore, we consider the possibilities for the efficient isolation and propagation of ILC3 from different organs and tissues for in-vitro and in-vivo studies. This paper calls upon uniformity in ILC3 definition, isolation, and propagation for the increased possibility of confluent interpretation of ILC3's role in immunity.
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Affiliation(s)
| | | | | | | | | | - Đorđe Miljković
- Department of Immunology, Institute for Biological Research “Siniša Stanković” - National Institute of Republic of Serbia, University of Belgrade, Belgrade, Serbia
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5
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Liang B, Xing D. Unveiling the mystery of ILC3s: Their functions and interactions in mucosal immunity. Int Immunopharmacol 2023; 123:110772. [PMID: 37552906 DOI: 10.1016/j.intimp.2023.110772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Revised: 08/02/2023] [Accepted: 08/03/2023] [Indexed: 08/10/2023]
Abstract
Innate lymphoid cells (ILCs) are a recently discovered subset of immune cells that play a crucial role in preserving tissue health and combating infections. Among these, ILC3s are particularly vital in regulating mucosal immunity across multiple organs such as the gut, lungs, and skin. The purpose of this article is to present a comprehensive and detailed overview of current knowledge on ILC3s, with a specific emphasis on their intricate interactions with various components of the intestinal microenvironment. Recent research on the complex, bidirectional communication pathways between ILC3s and intestinal epithelial cells, stromal cells, immune cells, microbiota, their metabolites, and diet are highlighted. Furthermore, this review comprehensively examines the diverse functions of ILC3s, which include lymphoid tissue development, tissue repair, infection, inflammation, and metabolic diseases, as well as the effector molecules that facilitate these functions. Overall, this review provides valuable insights into the biological and functional aspects of ILC3s and underscores their potential for developing innovative therapies for immune-mediated disorders, while also acknowledging the remaining knowledge gaps and challenges that need to be addressed.
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Affiliation(s)
- Bing Liang
- Cancer Institute, The Affiliated Hospital of Qingdao University, Qingdao, China; Qingdao Cancer Institute, Qingdao University, Qingdao, China.
| | - Dongming Xing
- Cancer Institute, The Affiliated Hospital of Qingdao University, Qingdao, China; Qingdao Cancer Institute, Qingdao University, Qingdao, China; School of Life Sciences, Tsinghua University, Beijing, China
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6
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Yoo JS, Oh SF. Unconventional immune cells in the gut mucosal barrier: regulation by symbiotic microbiota. Exp Mol Med 2023; 55:1905-1912. [PMID: 37696893 PMCID: PMC10545787 DOI: 10.1038/s12276-023-01088-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 07/19/2023] [Accepted: 08/08/2023] [Indexed: 09/13/2023] Open
Abstract
The mammalian gut is the most densely colonized organ by microbial species, which are in constant contact with the host throughout life. Hosts have developed multifaceted cellular and molecular mechanisms to distinguish and respond to benign and pathogenic bacteria. In addition to relatively well-characterized innate and adaptive immune cells, a growing body of evidence shows additional important players in gut mucosal immunity. Among them, unconventional immune cells, including innate lymphoid cells (ILCs) and unconventional T cells, are essential for maintaining homeostasis. These cells rapidly respond to bacterial signals and bridge the innate immunity and adaptive immunity in the mucosal barrier. Here, we focus on the types and roles of these immune cells in physiological and pathological conditions as prominent mechanisms by which the host immune system communicates with the gut microbiota in health and diseases.
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Affiliation(s)
- Ji-Sun Yoo
- Center for Experimental Therapeutics and Reperfusion Injury, Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women's Hospital, Boston, MA, USA
| | - Sungwhan F Oh
- Center for Experimental Therapeutics and Reperfusion Injury, Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women's Hospital, Boston, MA, USA.
- Graduate Program in Immunology, Harvard Medical School, Boston, MA, USA.
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7
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Cheng B, Sun Q, Li X, Xiao M, Wei X, Wang S. Vitamin A deficiency from maternal gestation may contribute to autistic-like behaviors and gastrointestinal dysfunction in rats through the disrupted purine and tryptophan metabolism. Behav Brain Res 2023; 452:114520. [PMID: 37268252 DOI: 10.1016/j.bbr.2023.114520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 05/18/2023] [Accepted: 05/29/2023] [Indexed: 06/04/2023]
Abstract
Vitamin A deficiency (VAD) has been linked to autism spectrum disorder (ASD) in multiple studies, and autistic children with gastrointestinal (GI) symptoms have been found to have lower VA levels than those without GI symptoms. However, the exact mechanism by which VAD causes both core symptoms and GI symptoms in ASD is ill defined. We constructed VAD and vitamin A normal (VAN) rat models from maternal gestation onwards. Autism-related behaviors were tested using the open-field test and the three-chamber test, and GI function was assessed with the GI transit time, the colonic transit time and fecal water content. Untargeted metabolomic analysis on the prefrontal cortex (PFC) and fecal samples was performed. VAD rats displayed autistic-like behaviors and impaired GI function compared to VAN rats. Metabolic profiles of both PFC and feces from VAD and VAN rats were significantly different. The differential metabolites in both PFC and feces between the VAN and VAD rats were mostly enriched in the purine metabolic pathway. Moreover, the most significantly affected metabolic pathway in PFC of VAD rats was the phenylalanine, tyrosine and tryptophan biosynthesis pathway, and the most remarkably altered metabolic pathway in the feces of VAD rats was the tryptophan metabolism pathway. These results indicate that VAD starting from maternal gestation might be linked to core symptoms of ASD and its GI co-occurring disorders through the purine and tryptophan-related metabolism disorders.
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Affiliation(s)
- Boli Cheng
- Department of Pediatrics, Affiliated Hospital of North Sichuan Medical College, Nanchong, China; Department of Clinical Medicine, North Sichuan Medical College, Nanchong, China
| | - Qunying Sun
- Department of Pediatrics, Affiliated Hospital of North Sichuan Medical College, Nanchong, China; Department of Clinical Medicine, North Sichuan Medical College, Nanchong, China
| | - Xinghui Li
- Department of Pediatrics, Affiliated Hospital of North Sichuan Medical College, Nanchong, China
| | - Meng Xiao
- Department of Pediatrics, Affiliated Hospital of North Sichuan Medical College, Nanchong, China
| | - Xiaoqin Wei
- Department of Medical Imaging, North Sichuan Medical College, Nanchong, China
| | - Si Wang
- Department of Pediatrics, Affiliated Hospital of North Sichuan Medical College, Nanchong, China; Department of Clinical Medicine, North Sichuan Medical College, Nanchong, China.
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8
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Li JH, Hepworth MR, O'Sullivan TE. Regulation of systemic metabolism by tissue-resident immune cell circuits. Immunity 2023; 56:1168-1186. [PMID: 37315533 PMCID: PMC10321269 DOI: 10.1016/j.immuni.2023.05.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 04/11/2023] [Accepted: 05/02/2023] [Indexed: 06/16/2023]
Abstract
Recent studies have demonstrated that tissue homeostasis and metabolic function are dependent on distinct tissue-resident immune cells that form functional cell circuits with structural cells. Within these cell circuits, immune cells integrate cues from dietary contents and commensal microbes in addition to endocrine and neuronal signals present in the tissue microenvironment to regulate structural cell metabolism. These tissue-resident immune circuits can become dysregulated during inflammation and dietary overnutrition, contributing to metabolic diseases. Here, we review the evidence describing key cellular networks within and between the liver, gastrointestinal tract, and adipose tissue that control systemic metabolism and how these cell circuits become dysregulated during certain metabolic diseases. We also identify open questions in the field that have the potential to enhance our understanding of metabolic health and disease.
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Affiliation(s)
- Joey H Li
- Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine at UCLA, Los Angeles, CA 900953, USA; Medical Scientist Training Program, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Matthew R Hepworth
- Division of Immunology, Immunity to Infection and Respiratory Medicine, Faculty of Biology, Medicine and Health, Manchester Collaborative Centre for Inflammation Research, Lydia Becker Institute of Immunology and Inflammation, Manchester Academic Health Science Centre, The University of Manchester, Manchester, UK
| | - Timothy E O'Sullivan
- Department of Microbiology, Immunology, and Molecular Genetics, David Geffen School of Medicine at UCLA, Los Angeles, CA 900953, USA.
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Feng J, Shan L, Miao C, Xue Y, Yue X, Jia F. The association of vitamin A, zinc and copper levels with clinical symptoms in children with autism spectrum disorders in Jilin Province, China. BMC Pediatr 2023; 23:173. [PMID: 37055789 PMCID: PMC10099696 DOI: 10.1186/s12887-023-03987-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 04/03/2023] [Indexed: 04/15/2023] Open
Abstract
BACKGROUND This study evaluated vitamin A (VA), copper (Cu), and zinc (Zn) levels in the population with autism spectrum disorder (ASD) in Jilin Province, China. Furthermore, we examined their links to core symptoms and neurodevelopment, as well as gastrointestinal (GI) comorbidities and sleep disorders. METHODS This study included 181 children with autism and 205 typically developing (TD) children. The participants had not taken vitamin/mineral supplements in the prior three months. High-performance liquid chromatography was used to measure serum VA levels. By using inductively coupled plasma-mass spectrometry, Zn and Cu concentrations in plasma were determined. Importantly, the Childhood Autism Rating Scale, the Social Responsiveness Scale, and the Autism Behavior Checklist were used to measure core ASD symptoms. However, the Griffith Mental Development Scales-Chinese were used to measure neurodevelopment. GI comorbidities and sleep abnormalities were assessed with the 6 Item-Gastrointestinal Severity Index and Children's Sleep Habits Questionnaire, respectively. Children with ASD with GI issues were grouped according to severity (low GI severity and high GI severity groups). RESULTS (i) The difference in VA, Zn, Cu levels and the Zn/Cu ratio between ASD and TD children is small. But children with ASD had lower VA levels and Zn/Cu ratio, higher Cu levels than TD children. Cu levels in children with ASD were associated with the severity of core symptoms. (ii) Children with ASD were much more likely than their TD counterparts to suffer from GI comorbidities or sleep problems. Furthermore, it was observed that high GI severity was associated with lower levels of VA, whereas low GI severity was associated with higher levels of VA. (iii) The children with ASD who had both lower VA and lower Zn/Cu ratio had more severe scores on the Autism Behavior Checklist, but not on other measures. CONCLUSION Children with ASD had lower VA and Zn/Cu ratio, and higher Cu levels. Cu levels in children with ASD were weakly correlated with one subscale on social or self-help. ASD children with lower VA levels may face more serious GI comorbidities. Children with ASD combined VA-Zn/Cu lower had more severe core symptoms. TRIAL REGISTRATION Registration number: ChiCTR-OPC-17013502. Date of registration: 2017-11-23.
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Affiliation(s)
- Junyan Feng
- Department of Developmental and Behavioral Pediatrics, The First Hospital of Jilin University, Changchun, 130021, China
| | - Ling Shan
- Department of Developmental and Behavioral Pediatrics, The First Hospital of Jilin University, Changchun, 130021, China
| | - Chunyue Miao
- Department of Developmental and Behavioral Pediatrics, The First Hospital of Jilin University, Changchun, 130021, China
| | - Yang Xue
- Department of Developmental and Behavioral Pediatrics, The First Hospital of Jilin University, Changchun, 130021, China
| | - Xiaojing Yue
- Department of Developmental and Behavioral Pediatrics, The First Hospital of Jilin University, Changchun, 130021, China
| | - Feiyong Jia
- Department of Developmental and Behavioral Pediatrics, The First Hospital of Jilin University, Changchun, 130021, China.
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10
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Zhang Y, Feng X, Chen J, Liu J, Wu J, Tan H, Mi Z, Rong P. Controversial role of ILC3s in intestinal diseases: A novelty perspective on immunotherapy. Front Immunol 2023; 14:1134636. [PMID: 37063879 PMCID: PMC10090672 DOI: 10.3389/fimmu.2023.1134636] [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: 12/30/2022] [Accepted: 03/13/2023] [Indexed: 03/31/2023] Open
Abstract
ILC3s have been identified as crucial immune regulators that play a role in maintaining host homeostasis and modulating the antitumor response. Emerging evidence supports the idea that LTi cells play an important role in initiating lymphoid tissue development, while other ILC3s can promote host defense and orchestrate adaptive immunity, mainly through the secretion of specific cytokines and crosstalk with other immune cells or tissues. Additionally, dysregulation of ILC3-mediated overexpression of cytokines, changes in subset abundance, and conversion toward other ILC subsets are closely linked with the occurrence of tumors and inflammatory diseases. Regulation of ILC3 cytokines, ILC conversion and LTi-induced TLSs may be a novel strategy for treating tumors and intestinal or extraintestinal inflammatory diseases. Herein, we discuss the development of ILCs, the biology of ILC3s, ILC plasticity, the correlation of ILC3s and adaptive immunity, crosstalk with the intestinal microenvironment, controversial roles of ILC3s in intestinal diseases and potential applications for treatment.
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Affiliation(s)
- Yunshu Zhang
- Department of Radiology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
- Xiangya School of Medicine, Central South University, Changsha, China
| | - Xuefei Feng
- Department of Government & Public Administration, The Chinese University of Hong Kong, Hong Kong, Hong Kong SAR, China
| | - Juan Chen
- Department of Radiology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Jiahao Liu
- Department of Radiology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Jianmin Wu
- Department of Radiology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Hongpei Tan
- Department of Radiology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
| | - Ze Mi
- Department of Radiology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
- *Correspondence: Ze Mi, ; Pengfei Rong,
| | - Pengfei Rong
- Department of Radiology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, China
- Key Laboratory of Biological Nanotechnology of National Health Commission, Xiangya Hospital, Central South University, Changsha, Hunan, China
- *Correspondence: Ze Mi, ; Pengfei Rong,
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11
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Asahi T, Abe S, Tajika Y, Rodewald HR, Sexl V, Takeshima H, Ikuta K. Retinoic acid receptor activity is required for the maintenance of type 1 innate lymphoid cells. Int Immunol 2023; 35:147-155. [PMID: 36480702 DOI: 10.1093/intimm/dxac057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2022] [Accepted: 12/05/2022] [Indexed: 12/13/2022] Open
Abstract
Group 1 innate lymphoid cells (G1-ILCs) are innate immune effectors critical for the response to intracellular pathogens and tumors. G1-ILCs comprise circulating natural killer (NK) cells and tissue-resident type 1 ILCs (ILC1s). ILC1s mainly reside in barrier tissues and provide the initial sources of interferon-γ (IFN-γ) to prime the protecting responses against infections, which are followed by the response of recruited NK cells. Despite such distribution differences, whether local environmental factors influence the behavior of NK cells and ILC1s is unclear. Here, we show that the signaling of retinoic acid (RA), active metabolites of vitamin A, is essential for the maintenance of ILC1s in the periphery. Mice expressing RARα403, a truncated form of retinoic acid receptor α (RARα) that exerts dominant negative activity, in a lymphoid cell- or G1-ILC-specific manner showed remarkable reductions of peripheral ILC1s while NK cells were unaffected. Lymphoid cell-specific inhibition of RAR activity resulted in the reduction of PD-1+ ILC progenitors (ILCPs), but not of common lymphoid progenitors (CLPs), suggesting the impaired commitment and differentiation of ILC1s. Transcriptome analysis revealed that RARα403-expressing ILC1s exhibited impaired proliferative states and declined expression of effector molecules. Thus, our findings demonstrate that cell-intrinsic RA signaling is required for the homeostasis and the functionality of ILC1s, which may present RA as critical environmental cue targeting local type 1 immunity against infection and cancer.
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Affiliation(s)
- Takuma Asahi
- Laboratory of Immune Regulation, Department of Virus Research, Institute for Life and Medical Sciences, Kyoto University, Kyoto 606-8507, Japan.,Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - Shinya Abe
- Laboratory of Immune Regulation, Department of Virus Research, Institute for Life and Medical Sciences, Kyoto University, Kyoto 606-8507, Japan.,Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - Yuya Tajika
- Laboratory of Immune Regulation, Department of Virus Research, Institute for Life and Medical Sciences, Kyoto University, Kyoto 606-8507, Japan.,Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan
| | - Hans-Reimer Rodewald
- Division of Cellular Immunology, German Cancer Research Center, Heidelberg 69120, Germany
| | - Veronika Sexl
- Institute of Pharmacology and Toxicology, University of Veterinary Medicine Vienna, 1210 Vienna, Austria
| | - Hiroshi Takeshima
- Department of Biological Chemistry, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan
| | - Koichi Ikuta
- Laboratory of Immune Regulation, Department of Virus Research, Institute for Life and Medical Sciences, Kyoto University, Kyoto 606-8507, Japan
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12
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Zhao N, Liu C, Li N, Zhou S, Guo Y, Yang S, Liu H. Role of Interleukin-22 in ulcerative colitis. Biomed Pharmacother 2023; 159:114273. [PMID: 36696801 DOI: 10.1016/j.biopha.2023.114273] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 01/16/2023] [Accepted: 01/17/2023] [Indexed: 01/25/2023] Open
Abstract
Ulcerative Colitis (UC) is a chronic disease, in the progression of which an immune overreaction may play an important role. IL-22 is a member of the IL-10 superfamily of cytokines and is pleiotropic in immune regulation and inflammatory responses. IL-22 can produce protective effects, promote wound healing and tissue regeneration, while it can also induce inflammatory reactions when it is chronically overexpressed. Extensive literatures reported that IL-22 played an essential role in the pathogenic development of UC. IL-22 participates in the whole disease process of UC involving signaling pathways, gene expression regulation, and intestinal flora imbalance, making IL-22 a possible candidate for the treatment of UC. In this paper, the latest knowledge to further elucidate the role of IL-22 in UC was summarized and analyzed.
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Affiliation(s)
- Nan Zhao
- College of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan 250355, PR China.
| | - Chuanguo Liu
- Experimental Center, Shandong University of Traditional Chinese Medicine, Jinan 250355, PR China.
| | - Ning Li
- College of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan 250355, PR China.
| | - Shuang Zhou
- College of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan 250355, PR China.
| | - Yuting Guo
- College of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan 250355, PR China.
| | - Shihua Yang
- Department of Oncology, The Fifth People's Hospital of Jinan, Jinan 250022, PR China.
| | - Huimin Liu
- College of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan 250355, PR China.
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13
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Bastos-Amador P, Duarte EL, Torres J, Caldeira AT, Silva I, Salvador C, Assunção R, Alvito P, Ferreira M. Maternal dietary exposure to mycotoxin aflatoxin B 1 promotes intestinal immune alterations and microbiota modifications increasing infection susceptibility in mouse offspring. Food Chem Toxicol 2023; 173:113596. [PMID: 36603704 DOI: 10.1016/j.fct.2022.113596] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 12/19/2022] [Accepted: 12/28/2022] [Indexed: 01/03/2023]
Abstract
Mycotoxins are secondary metabolites produced by fungi occurring in food that are toxic to animals and humans. Early-life mycotoxins exposure has been linked to diverse pathologies. However, how maternal exposure to mycotoxins impacts on the intestinal barrier function of progeny has not been explored. Here, exposure of pregnant and lactating C57Bl/6J female mice to aflatoxin B1 (AFB1; 400 μg/kg body weight/day; 3 times a week) in gelatine pellets, from embryonic day (E)11.5 until weaning (postnatal day 21), led to gut immunological changes in progeny. The results showed an overall increase of lymphocyte number in intestine, a reduction of expression of epithelial genes related to microbial defence, as well as a decrease in cytokine production by intestinal type 2 innate lymphoid cells (ILC2). While susceptibility to chemically induced colitis was not worsened, immune alterations were associated with changes in gut microbiota and with a higher vulnerability to infection by the protozoan Eimeria vermiformis at early-life. Together these results show that maternal dietary exposure to AFB1 can dampen intestinal barrier homeostasis in offspring decreasing their capability to tackle intestinal pathogens. These data provide insights to understand AFB1 potential harmfulness in early-life health in the context of intestinal infections.
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Affiliation(s)
- Patricia Bastos-Amador
- Food and Nutrition Department, National Institute of Health Dr. Ricardo Jorge, 1649-016, Lisbon, Portugal; Champalimaud Foundation, Champalimaud Centre for the Unknown, 1400-038, Lisbon, Portugal
| | - Elsa Leclerc Duarte
- University of Évora, School of Science and Technology, 7000-671, Évora, Portugal; MED-Mediterranean Institute for Agriculture, Environment and Development, 7006-554, Évora, Portugal
| | - Júlio Torres
- University of Coimbra, Center for Innovative Biomedicine and Biotechnology, Center for Neuroscience and Cell Biology, 3004-504, Coimbra, Portugal
| | | | - Inês Silva
- University of Évora, School of Science and Technology, 7000-671, Évora, Portugal; MED-Mediterranean Institute for Agriculture, Environment and Development, 7006-554, Évora, Portugal; HERCULES Laboratory, Universidade de Évora, 7000-809, Évora, Portugal
| | - Cátia Salvador
- HERCULES Laboratory, Universidade de Évora, 7000-809, Évora, Portugal
| | - Ricardo Assunção
- IUEM, Instituto Universitário Egas Moniz, Egas Moniz-Cooperativa de Ensino Superior, CRL, 2829 - 511, Caparica, Portugal; University of Aveiro, CESAM - Centre for Environmental and Marine Studies, 3810-193, Aveiro, Portugal
| | - Paula Alvito
- Food and Nutrition Department, National Institute of Health Dr. Ricardo Jorge, 1649-016, Lisbon, Portugal; University of Aveiro, CESAM - Centre for Environmental and Marine Studies, 3810-193, Aveiro, Portugal
| | - Manuela Ferreira
- Champalimaud Foundation, Champalimaud Centre for the Unknown, 1400-038, Lisbon, Portugal; University of Coimbra, Center for Innovative Biomedicine and Biotechnology, Center for Neuroscience and Cell Biology, 3004-504, Coimbra, Portugal.
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14
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Higashiyama M, Miura S, Hokari R. Modulation by luminal factors on the functions and migration of intestinal innate immunity. Front Immunol 2023; 14:1113467. [PMID: 36860849 PMCID: PMC9968923 DOI: 10.3389/fimmu.2023.1113467] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 01/25/2023] [Indexed: 02/15/2023] Open
Abstract
Luminal antigens, nutrients, metabolites from commensal bacteria, bile acids, or neuropeptides influence the function and trafficking of immune cells in the intestine. Among the immune cells in the gut, innate lymphoid cells, including macrophages, neutrophils, dendritic cells, mast cells, and innate lymphoid cells, play an important role for the maintenance of intestinal homeostasis through a rapid immune response to luminal pathogens. These innate cells are influenced by several luminal factors, possibly leading to dysregulated gut immunity and intestinal disorders such as inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), and intestinal allergy. Luminal factors are sensed by distinct neuro-immune cell units, which also have a strong impact on immunoregulation of the gut. Immune cell trafficking from the blood stream through the lymphatic organ to lymphatics, an essential function for immune responses, is also modulated by luminal factors. This mini-review examines knowledge of luminal and neural factors that regulate and modulate response and migration of leukocytes including innate immune cells, some of which are clinically associated with pathological intestinal inflammation.
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Affiliation(s)
- Masaaki Higashiyama
- Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan,*Correspondence: Masaaki Higashiyama,
| | - Soichiro Miura
- International University of Health and Welfare, Tokyo, Japan
| | - Ryota Hokari
- Department of Internal Medicine, National Defense Medical College, Tokorozawa, Japan
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15
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Zhou J, Yue J, Yao Y, Hou P, Zhang T, Zhang Q, Yi L, Mi M. Dihydromyricetin Protects Intestinal Barrier Integrity by Promoting IL-22 Expression in ILC3s through the AMPK/SIRT3/STAT3 Signaling Pathway. Nutrients 2023; 15:nu15020355. [PMID: 36678226 PMCID: PMC9861697 DOI: 10.3390/nu15020355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 01/06/2023] [Accepted: 01/08/2023] [Indexed: 01/12/2023] Open
Abstract
BACKGROUND Previous studies indicate that dihydromyricetin (DHM) could alleviate intestinal inflammation and improve intestinal barrier integrity, yet the underlying mechanism remains obscure. METHODS C57BL/6 male mice were fed with a control diet, high-fat diet (HFD), or HFD + DHM diet for 12 weeks. The intestinal permeability and expression of intestinal tight junction (TJ) protein were detected to evaluate the effects of DHM on intestinal barrier integrity. The interleukin 22 (IL-22) production of group 3 innate lymphoid cells (ILC3s) in small intestine lamina propria was tested to clarify the effects of DHM on ILC3s. In addition, an MNK3 cell line, which expresses the same transcription factors and cytokines as ILC3, was used to investigate the molecular mechanism under DHM-induced IL-22 expression. RESULTS DHM effectively protected HFD-fed mice against intestinal barrier destruction by promoting ILC3 activation and IL-22 secretion, and IL-22 expression increased the expression levels of TJ molecules to protect intestinal barrier integrity. Moreover, DHM increased activation of the AMPK/SIRT3/STAT3 pathway, which in turn promoted IL-22 expression in MNK3 cells. CONCLUSIONS DHM improved IL-22 production in ILC3 cells to alleviate HFD-induced intestinal barrier destruction via the AMPK/SIRT3/STAT3 pathway.
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Affiliation(s)
| | | | | | | | | | | | - Long Yi
- Correspondence: (L.Y.); or mantian (M.M.); Tel./Fax: +86-2368771549 (M.M.)
| | - Mantian Mi
- Correspondence: (L.Y.); or mantian (M.M.); Tel./Fax: +86-2368771549 (M.M.)
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16
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Ghilas S, O’Keefe R, Mielke LA, Raghu D, Buchert M, Ernst M. Crosstalk between epithelium, myeloid and innate lymphoid cells during gut homeostasis and disease. Front Immunol 2022; 13:944982. [PMID: 36189323 PMCID: PMC9524271 DOI: 10.3389/fimmu.2022.944982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 08/29/2022] [Indexed: 12/05/2022] Open
Abstract
The gut epithelium not only provides a physical barrier to separate a noxious outside from a sterile inside but also allows for highly regulated interactions between bacteria and their products, and components of the immune system. Homeostatic maintenance of an intact epithelial barrier is paramount to health, requiring an intricately regulated and highly adaptive response of various cells of the immune system. Prolonged homeostatic imbalance can result in chronic inflammation, tumorigenesis and inefficient antitumor immune control. Here we provide an update on the role of innate lymphoid cells, macrophages and dendritic cells, which collectively play a critical role in epithelial barrier maintenance and provide an important linkage between the classical innate and adaptive arm of the immune system. These interactions modify the capacity of the gut epithelium to undergo continuous renewal, safeguard against tumor formation and provide feedback to the gut microbiome, which acts as a seminal contributor to cellular homeostasis of the gut.
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Affiliation(s)
- Sonia Ghilas
- Mucosal Immunity Laboratory, Olivia Newton-John Cancer Research Institute, and La Trobe University - School of Cancer Medicine, Heidelberg, VIC, Australia
| | - Ryan O’Keefe
- Cancer and Inflammation Program, Olivia Newton-John Cancer Research Institute, and La Trobe University - School of Cancer Medicine, Heidelberg, VIC, Australia
| | - Lisa Anna Mielke
- Mucosal Immunity Laboratory, Olivia Newton-John Cancer Research Institute, and La Trobe University - School of Cancer Medicine, Heidelberg, VIC, Australia
| | - Dinesh Raghu
- Mucosal Immunity Laboratory, Olivia Newton-John Cancer Research Institute, and La Trobe University - School of Cancer Medicine, Heidelberg, VIC, Australia
| | - Michael Buchert
- Cancer and Inflammation Program, Olivia Newton-John Cancer Research Institute, and La Trobe University - School of Cancer Medicine, Heidelberg, VIC, Australia
- *Correspondence: Michael Buchert, ; Matthias Ernst,
| | - Matthias Ernst
- Cancer and Inflammation Program, Olivia Newton-John Cancer Research Institute, and La Trobe University - School of Cancer Medicine, Heidelberg, VIC, Australia
- *Correspondence: Michael Buchert, ; Matthias Ernst,
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17
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Jowett GM, Read E, Roberts LB, Coman D, Vilà González M, Zabinski T, Niazi U, Reis R, Trieu TJ, Danovi D, Gentleman E, Vallier L, Curtis MA, Lord GM, Neves JF. Organoids capture tissue-specific innate lymphoid cell development in mice and humans. Cell Rep 2022; 40:111281. [PMID: 36044863 PMCID: PMC9638027 DOI: 10.1016/j.celrep.2022.111281] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 01/06/2022] [Accepted: 08/05/2022] [Indexed: 12/21/2022] Open
Abstract
Organoid-based models of murine and human innate lymphoid cell precursor (ILCP) maturation are presented. First, murine intestinal and pulmonary organoids are harnessed to demonstrate that the epithelial niche is sufficient to drive tissue-specific maturation of all innate lymphoid cell (ILC) groups in parallel, without requiring subset-specific cytokine supplementation. Then, more complex human induced pluripotent stem cell (hiPSC)-based gut and lung organoid models are used to demonstrate that human epithelial cells recapitulate maturation of ILC from a stringent systemic human ILCP population, but only when the organoid-associated stromal cells are depleted. These systems offer versatile and reductionist models to dissect the impact of environmental and mucosal niche cues on ILC maturation. In the future, these could provide insight into how ILC activity and development might become dysregulated in chronic inflammatory diseases.
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Affiliation(s)
- Geraldine M Jowett
- School for Immunology and Microbial Sciences, King's College London, London SE1 9RT, UK; Centre for Host Microbiome Interactions, King's College London, London SE1 9RT, UK; Centre for Craniofacial and Regenerative Biology, King's College London, London SE1 9RT, UK; Centre for Gene Therapy & Regenerative Medicine, King's College London, London SE1 9RT, UK; Wellcome Trust Cell Therapies and Regenerative Medicine Ph.D. Programme, London SE1 9RT, UK
| | - Emily Read
- School for Immunology and Microbial Sciences, King's College London, London SE1 9RT, UK; Centre for Host Microbiome Interactions, King's College London, London SE1 9RT, UK; Centre for Gene Therapy & Regenerative Medicine, King's College London, London SE1 9RT, UK
| | - Luke B Roberts
- School for Immunology and Microbial Sciences, King's College London, London SE1 9RT, UK
| | - Diana Coman
- Centre for Host Microbiome Interactions, King's College London, London SE1 9RT, UK
| | - Marta Vilà González
- Wellcome and MRC Cambridge Stem Cell Institute, Puddicombe Way, Cambridge CB2 0AW, UK; Department of Surgery, University of Cambridge and NIHR Cambridge Biomedical Research Centre, Hills Road, Cambridge CB2 0QQ, UK
| | - Tomasz Zabinski
- School for Immunology and Microbial Sciences, King's College London, London SE1 9RT, UK
| | - Umar Niazi
- Guy's and St. Thomas' National Health Service Foundation Trust and King's College London National Institute for Health and Care Research Biomedical Research Centre Translational Bioinformatics Platform, Guy's Hospital, London SE1 9RT, UK
| | - Rita Reis
- School for Immunology and Microbial Sciences, King's College London, London SE1 9RT, UK
| | - Tung-Jui Trieu
- Centre for Host Microbiome Interactions, King's College London, London SE1 9RT, UK; Centre for Craniofacial and Regenerative Biology, King's College London, London SE1 9RT, UK
| | - Davide Danovi
- Centre for Craniofacial and Regenerative Biology, King's College London, London SE1 9RT, UK; bit.bio, Babraham Research Campus, The Dorothy Hodgkin Building, Cambridge CB22 3FH, UK
| | - Eileen Gentleman
- Centre for Craniofacial and Regenerative Biology, King's College London, London SE1 9RT, UK
| | - Ludovic Vallier
- Wellcome and MRC Cambridge Stem Cell Institute, Puddicombe Way, Cambridge CB2 0AW, UK; Department of Surgery, University of Cambridge and NIHR Cambridge Biomedical Research Centre, Hills Road, Cambridge CB2 0QQ, UK
| | - Michael A Curtis
- Centre for Host Microbiome Interactions, King's College London, London SE1 9RT, UK
| | - Graham M Lord
- School for Immunology and Microbial Sciences, King's College London, London SE1 9RT, UK; Faculty of Biology, Medicine and Health, University of Manchester, Oxford Road, Manchester M13 9PL, UK
| | - Joana F Neves
- School for Immunology and Microbial Sciences, King's College London, London SE1 9RT, UK; Centre for Host Microbiome Interactions, King's College London, London SE1 9RT, UK.
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18
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Surace L, Di Santo JP. Local and systemic features of ILC immunometabolism. Curr Opin Hematol 2022; 29:209-217. [PMID: 35787549 DOI: 10.1097/moh.0000000000000722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE OF REVIEW Innate lymphoid cells (ILCs) are specialized immune cells that rapidly sense environmental perturbations and regulate immune responses and tissue homeostasis. ILCs are mainly tissue resident and their crosstalk within tissue microenvironments influences both local and systemic metabolism. Reciprocally, metabolic status conditions ILC phenotype and effector function. In this review, we discuss the role of ILCs as metabolic sentinels and describe how ILC subset-specific activities influence homeostasis and disease. Finally, we highlight emerging challenges in the field of ILC immunometabolism. RECENT FINDINGS Accumulating evidence suggests that ILCs metabolism, phenotype, and function are shaped by signals from the tissue microenvironment. Dietary, endogenous, and microbial metabolites are sensed by ILC subsets and can impact on ILC-mediated immune responses. Recent studies have found that mitochondria are central regulators of ILC effector function. Furthermore, ILCs have emerged as crucial sensors of metabolic stress, suggesting they might act as metabolic sentinels, coordinating tissue and host metabolism. SUMMARY Our understanding how ILCs mechanistically regulate host metabolism and defenses is still incomplete. Unraveling critical metabolic features of ILCs may lead to novel therapeutic strategies that target these cells in the context of disease.
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Affiliation(s)
- Laura Surace
- Institute of Clinical Chemistry and Clinical Pharmacology, University Hospital Bonn, , Bonn, Germany
| | - James P Di Santo
- Institut Pasteur, Université Paris Cité, Inserm, Paris, France
- Innate Immunity Unit, Institut Pasteur, Université Paris Cité, Inserm U1223, Paris, France
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19
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Pelletier A, Stockmann C. The Metabolic Basis of ILC Plasticity. Front Immunol 2022; 13:858051. [PMID: 35572512 PMCID: PMC9099248 DOI: 10.3389/fimmu.2022.858051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 04/04/2022] [Indexed: 11/17/2022] Open
Abstract
Innate Lymphoid Cells (ILCs) are the innate counterpart of adaptive lymphoid T cells. They are key players in the regulation of tissues homeostasis and early inflammatory host responses. ILCs are divided into three groups, and further subdivided into five subsets, that are characterised by distinct transcription factors, surface markers and their cytokine expression profiles. Group 1 ILCs, including natural killer (NK) cells and non-NK cell ILC1s, express T-bet and produce IFN-γ. Group 2 ILCs depend on GATA3 and produce IL-4, IL-5 and IL-13. Group 3 ILCs, composed of ILC3s and Lymphoid Tissue Inducer (LTi) cells, express RORγt and produce IL-17 and IL-22. Even though, the phenotype of each subset is well defined, environmental signals can trigger the interconversion of phenotypes and the plasticity of ILCs, in both mice and humans. Several extrinsic and intrinsic drivers of ILC plasticity have been described. However, the changes in cellular metabolism that underlie ILC plasticity remain largely unexplored. Given that metabolic changes critically affect fate and effector function of several immune cell types, we, here, review recent findings on ILC metabolism and discuss the implications for ILC plasticity.
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20
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Sidell N, Kane MA. Actions of Retinoic Acid in the Pathophysiology of HIV Infection. Nutrients 2022; 14:nu14081611. [PMID: 35458172 PMCID: PMC9029687 DOI: 10.3390/nu14081611] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 04/01/2022] [Accepted: 04/02/2022] [Indexed: 02/05/2023] Open
Abstract
The vitamin A metabolite all-trans retinoic acid (RA) plays a key role in tissue homeostasis and mucosal immunity. RA is produced by gut-associated dendritic cells, which are among the first cells encountered by HIV. Acute HIV infection results in rapid reduction of RA levels and dysregulation of immune cell populations whose identities and function are largely controlled by RA. Here, we discuss the potential link between the roles played by RA in shaping intestinal immune responses and the manifestations and pathogenesis of HIV-associated enteropathy and similar conditions observed in SIV-infected non-human primate models. We also present data demonstrating the ability of RA to enhance the activation of replication-competent viral reservoirs from subjects on suppressive anti-retroviral therapy. The data suggest that retinoid supplementation may be a useful adjuvant for countering the pathologic condition of the gastro-intestinal tract associated with HIV infection and as part of a strategy for reactivating viral reservoirs as a means of depleting latent viral infection.
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Affiliation(s)
- Neil Sidell
- Department of Obstetrics and Gynecology, Emory University School of Medicine, Atlanta, GA 30322, USA
- Correspondence: (N.S.); (M.A.K.)
| | - Maureen A. Kane
- Department of Pharmaceutical Sciences, University of Maryland School of Pharmacy, Baltimore, MD 21201, USA
- Correspondence: (N.S.); (M.A.K.)
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21
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Tai SL, Mortha A. Macrophage control of Crohn's disease. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2022; 367:29-64. [PMID: 35461659 DOI: 10.1016/bs.ircmb.2022.01.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
The intestinal tract is the body's largest mucosal surface and permanently exposed to microbial and environmental signals. Maintaining a healthy intestine requires the presence of sentinel grounds keeper cells, capable of controlling immunity and tissue homeostasis through specialized functions. Intestinal macrophages are such cells and important players in steady-state functions and during acute and chronic inflammation. Crohn's disease, a chronic inflammatory condition of the intestinal tract is proposed to be the consequence of an altered immune system through microbial and environmental stimulation. This hypothesis suggests an involvement of macrophages in the regulation of this pathology. Within this chapter, we will discuss intestinal macrophage development and highlight data suggesting their implication in chronic intestinal pathologies like Crohn's disease.
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Affiliation(s)
- Siu Ling Tai
- Department of Immunology, University of Toronto, Toronto, ON, Canada
| | - Arthur Mortha
- Department of Immunology, University of Toronto, Toronto, ON, Canada.
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22
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Cairo C, Webb TJ. Effective Barriers: The Role of NKT Cells and Innate Lymphoid Cells in the Gut. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2022; 208:235-246. [PMID: 35017213 DOI: 10.4049/jimmunol.2100799] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 10/19/2021] [Indexed: 06/14/2023]
Abstract
The critical role of commensal microbiota in regulating the host immune response has been established. In addition, it is known that host-microbial interactions are bidirectional, and this interplay is tightly regulated to prevent chronic inflammatory disease. Although many studies have focused on the role of classic T cell subsets, unconventional lymphocytes such as NKT cells and innate lymphoid cells also contribute to the regulation of homeostasis at mucosal surfaces and influence the composition of the intestinal microbiota. In this review, we discuss the mechanisms involved in the cross-regulation between NKT cells, innate lymphoid cells, and the gut microbiota. Moreover, we highlight how disruptions in homeostasis can lead to immune-mediated disorders.
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Affiliation(s)
- Cristiana Cairo
- Department of Medicine, University of Maryland School of Medicine, Baltimore, MD;
- Institute of Human Virology, University of Maryland School of Medicine, Baltimore, MD
| | - Tonya J Webb
- Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD; and
- Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland School of Medicine, Baltimore, MD
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23
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Research Progress in Vitamin A and Autism Spectrum Disorder. Behav Neurol 2021; 2021:5417497. [PMID: 34917197 PMCID: PMC8670912 DOI: 10.1155/2021/5417497] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 10/15/2021] [Indexed: 12/12/2022] Open
Abstract
Autism spectrum disorder (ASD) is a highly heterogeneous neurodevelopmental disorder. Over the past few decades, many studies have investigated the effects of VA supplementation in ASD patients and the relationship between vitamin A (VA) levels and ASD. VA is an essential micronutrient that plays an important role in various systems and biological processes in the form of retinoic acid (RA). Recent studies have shown that serum VA concentration is negatively correlated with the severity of ASD. The lack of VA during pregnancy or early fetal development can affect brain development and lead to long-term or even permanent impairment in the learning process, memory formation, and cognitive function. In addition, VA deficiency has been reported to have a major impact on the gastrointestinal function of children with ASD, while VA supplementation has been shown to improve the symptoms of ASD to a certain extent. This paper provides a comprehensive review of the relationship between VA and ASD.
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24
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Elemam NM, Ramakrishnan RK, Hundt JE, Halwani R, Maghazachi AA, Hamid Q. Innate Lymphoid Cells and Natural Killer Cells in Bacterial Infections: Function, Dysregulation, and Therapeutic Targets. Front Cell Infect Microbiol 2021; 11:733564. [PMID: 34804991 PMCID: PMC8602108 DOI: 10.3389/fcimb.2021.733564] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 10/19/2021] [Indexed: 12/12/2022] Open
Abstract
Infectious diseases represent one of the largest medical challenges worldwide. Bacterial infections, in particular, remain a pertinent health challenge and burden. Moreover, such infections increase over time due to the continuous use of various antibiotics without medical need, thus leading to several side effects and bacterial resistance. Our innate immune system represents our first line of defense against any foreign pathogens. This system comprises the innate lymphoid cells (ILCs), including natural killer (NK) cells that are critical players in establishing homeostasis and immunity against infections. ILCs are a group of functionally heterogenous but potent innate immune effector cells that constitute tissue-resident sentinels against intracellular and extracellular bacterial infections. Being a nascent subset of innate lymphocytes, their role in bacterial infections is not clearly understood. Furthermore, these pathogens have developed methods to evade the host immune system, and hence permit infection spread and tissue damage. In this review, we highlight the role of the different ILC populations in various bacterial infections and the possible ways of immune evasion. Additionally, potential immunotherapies to manipulate ILC responses will be briefly discussed.
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Affiliation(s)
- Noha Mousaad Elemam
- Sharjah Institute for Medical Research, College of Medicine, University of Sharjah, Sharjah, United Arab Emirates.,Department of Clinical Sciences, College of Medicine, University of Sharjah, Sharjah, United Arab Emirates
| | - Rakhee K Ramakrishnan
- Sharjah Institute for Medical Research, College of Medicine, University of Sharjah, Sharjah, United Arab Emirates.,Department of Clinical Sciences, College of Medicine, University of Sharjah, Sharjah, United Arab Emirates
| | - Jennifer E Hundt
- Lübeck Institute for Experimental Dermatology, University of Lübeck, Lübeck, Germany
| | - Rabih Halwani
- Sharjah Institute for Medical Research, College of Medicine, University of Sharjah, Sharjah, United Arab Emirates.,Department of Clinical Sciences, College of Medicine, University of Sharjah, Sharjah, United Arab Emirates.,Prince Abdullah Ben Khaled Celiac Disease Chair, Department of Pediatrics, Faculty of Medicine, King Saud University, Riyadh, Saudi Arabia
| | - Azzam A Maghazachi
- Sharjah Institute for Medical Research, College of Medicine, University of Sharjah, Sharjah, United Arab Emirates.,Department of Clinical Sciences, College of Medicine, University of Sharjah, Sharjah, United Arab Emirates
| | - Qutayba Hamid
- Sharjah Institute for Medical Research, College of Medicine, University of Sharjah, Sharjah, United Arab Emirates.,Department of Clinical Sciences, College of Medicine, University of Sharjah, Sharjah, United Arab Emirates.,Meakins-Christie Laboratories, McGill University, Montreal, QC, Canada
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25
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Orimo K, Tamari M, Saito H, Matsumoto K, Nakae S, Morita H. Characteristics of tissue-resident ILCs and their potential as therapeutic targets in mucosal and skin inflammatory diseases. Allergy 2021; 76:3332-3348. [PMID: 33866593 DOI: 10.1111/all.14863] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 03/30/2021] [Accepted: 04/12/2021] [Indexed: 12/11/2022]
Abstract
Discovery of innate lymphoid cells (ILCs), which are non-T and non-B lymphocytes that have no antigen-specific receptors, changed the classical concept of the mechanism of allergy, which had been explained mainly as antigen-specific acquired immunity based on IgE and Th2 cells. The discovery led to dramatic improvement in our understanding of the mechanism of non-IgE-mediated allergic inflammation. Numerous studies conducted in the past decade have elucidated the characteristics of each ILC subset in various organs and tissues and their ontogeny. We now know that each ILC subset exhibits heterogeneity. Moreover, the functions and activating/suppressing factors of each ILC subset were found to differ among both organs and types of tissue. Therefore, in this review, we summarize our current knowledge of ILCs by focusing on the organ/tissue-specific features of each subset to understand their roles in various organs. We also discuss ILCs' involvement in human inflammatory diseases in various organs and potential therapeutic/preventive strategies that target ILCs.
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Affiliation(s)
- Keisuke Orimo
- Department of Allergy and Clinical Immunology National Research Institute for Child Health and Development Tokyo Japan
| | - Masato Tamari
- Department of Allergy and Clinical Immunology National Research Institute for Child Health and Development Tokyo Japan
| | - Hirohisa Saito
- Department of Allergy and Clinical Immunology National Research Institute for Child Health and Development Tokyo Japan
| | - Kenji Matsumoto
- Department of Allergy and Clinical Immunology National Research Institute for Child Health and Development Tokyo Japan
| | - Susumu Nakae
- Graduate School of Integrated Sciences for Life Hiroshima University Hiroshima Japan
- Precursory Research for Embryonic Science and Technology Japan Science and Technology Agency Saitama Japan
| | - Hideaki Morita
- Department of Allergy and Clinical Immunology National Research Institute for Child Health and Development Tokyo Japan
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26
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Džopalić T, Božić-Nedeljković B, Jurišić V. The role of vitamin A and vitamin D in modulation of the immune response with a focus on innate lymphoid cells. Cent Eur J Immunol 2021; 46:264-269. [PMID: 34764797 PMCID: PMC8568032 DOI: 10.5114/ceji.2021.103540] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2020] [Accepted: 01/03/2021] [Indexed: 01/21/2023] Open
Abstract
The immune system with its numerous and complex interactions helps to protect the host from pathogenic microorganisms, and enables cleaning of damaged tissues. It is also associated with constant "monitoring" of the appearance of malignant cells and their elimination that can occur in the human body. Such a role depends on many factors including adequate intake of nutrients, including vitamins. The effect of vitamin supplementation on the modulation of the immune response has always been the focus of numerous studies. Vitamins A and D have been shown to have the greatest immune-modulatory effect. In this review, we discuss and consider the possible roles of vitamins A and D on the immune response through innate and adaptive immune cells, with special focus on the cell population recently characterized as innate lymphoid cells. Recent literature data indicate that vitamin A and its metabolites modulate the balance between Th1 and Th2 immunity. In addition, vitamin D expresses protective effects on the innate immune system and inhibitory effects on adaptive immunity.
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Affiliation(s)
- Tanja Džopalić
- Department of Immunology, University of Niš, Medical Faculty, Niš, Serbia
| | - Biljana Božić-Nedeljković
- Institute for Physiology and Biochemistry “Ivan Djaja” Belgrade, Faculty of Biology, University of Belgrade, Serbia
| | - Vladimir Jurišić
- Faculty of Medical Sciences, University of Kragujevac, Kragujevac, Serbia
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27
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Group 3 innate lymphoid cells mediate host defense against attaching and effacing pathogens. Curr Opin Microbiol 2021; 63:83-91. [PMID: 34274597 DOI: 10.1016/j.mib.2021.06.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 06/22/2021] [Accepted: 06/24/2021] [Indexed: 01/03/2023]
Abstract
Group 3 innate lymphoid cells (ILC3) are innate effector cells that have essential roles in lymphoid organogenesis and maintenance of tissue homeostasis under steady-state and pathogenic conditions. ILC3 also promote immune defense, notably during bacterial breach of epithelial barriers, including those caused by attaching and effacing (A/E) pathogens for which Citrobacter rodentium infection in mice is a relevant pre-clinical model. Through their ability to sustain interactions with tissue-resident immune cells, epithelial cells, neurons or stromal cells, ILC3 constitute a key orchestrator that maintains the intestinal barrier. In this review, we will examine the function of murine ILC3 in host defense against C. rodentium infection and provide a discussion of recent advances that help elucidate the specific roles of these novel innate immune effector cells at mucosal surfaces.
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Caffaratti C, Plazy C, Mery G, Tidjani AR, Fiorini F, Thiroux S, Toussaint B, Hannani D, Le Gouellec A. What We Know So Far about the Metabolite-Mediated Microbiota-Intestinal Immunity Dialogue and How to Hear the Sound of This Crosstalk. Metabolites 2021; 11:406. [PMID: 34205653 PMCID: PMC8234899 DOI: 10.3390/metabo11060406] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2021] [Revised: 06/15/2021] [Accepted: 06/16/2021] [Indexed: 12/25/2022] Open
Abstract
Trillions of microorganisms, termed the "microbiota", reside in the mammalian gastrointestinal tract, and collectively participate in regulating the host phenotype. It is now clear that the gut microbiota, metabolites, and intestinal immune function are correlated, and that alterations of the complex and dynamic host-microbiota interactions can have deep consequences for host health. However, the mechanisms by which the immune system regulates the microbiota and by which the microbiota shapes host immunity are still not fully understood. This article discusses the contribution of metabolites in the crosstalk between gut microbiota and immune cells. The identification of key metabolites having a causal effect on immune responses and of the mechanisms involved can contribute to a deeper insight into host-microorganism relationships. This will allow a better understanding of the correlation between dysbiosis, microbial-based dysmetabolism, and pathogenesis, thus creating opportunities to develop microbiota-based therapeutics to improve human health. In particular, we systematically review the role of soluble and membrane-bound microbial metabolites in modulating host immunity in the gut, and of immune cells-derived metabolites affecting the microbiota, while discussing evidence of the bidirectional impact of this crosstalk. Furthermore, we discuss the potential strategies to hear the sound of such metabolite-mediated crosstalk.
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Affiliation(s)
- Clément Caffaratti
- Faculty of Medicine, CNRS, Grenoble INP, CHU Grenoble-Alpes, University Grenoble Alpes, TIMC (UMR5525), 38000 Grenoble, France; (C.C.); (C.P.); (G.M.); (A.-R.T.); (S.T.); (B.T.)
| | - Caroline Plazy
- Faculty of Medicine, CNRS, Grenoble INP, CHU Grenoble-Alpes, University Grenoble Alpes, TIMC (UMR5525), 38000 Grenoble, France; (C.C.); (C.P.); (G.M.); (A.-R.T.); (S.T.); (B.T.)
- Service de Biochimie Biologie Moléculaire Toxicologie Environnementale, UM Biochimie des Enzymes et des Protéines, Institut de Biologie et Pathologie, CHU Grenoble-Alpes, 38000 Grenoble, France
- Plateforme de Métabolomique GEMELI-GExiM, Institut de Biologie et Pathologie, CHU Grenoble-Alpes, 38000 Grenoble, France;
| | - Geoffroy Mery
- Faculty of Medicine, CNRS, Grenoble INP, CHU Grenoble-Alpes, University Grenoble Alpes, TIMC (UMR5525), 38000 Grenoble, France; (C.C.); (C.P.); (G.M.); (A.-R.T.); (S.T.); (B.T.)
- Department of Infectiology-Pneumology, CHU Grenoble-Alpes, 38000 Grenoble, France
| | - Abdoul-Razak Tidjani
- Faculty of Medicine, CNRS, Grenoble INP, CHU Grenoble-Alpes, University Grenoble Alpes, TIMC (UMR5525), 38000 Grenoble, France; (C.C.); (C.P.); (G.M.); (A.-R.T.); (S.T.); (B.T.)
| | - Federica Fiorini
- Plateforme de Métabolomique GEMELI-GExiM, Institut de Biologie et Pathologie, CHU Grenoble-Alpes, 38000 Grenoble, France;
| | - Sarah Thiroux
- Faculty of Medicine, CNRS, Grenoble INP, CHU Grenoble-Alpes, University Grenoble Alpes, TIMC (UMR5525), 38000 Grenoble, France; (C.C.); (C.P.); (G.M.); (A.-R.T.); (S.T.); (B.T.)
| | - Bertrand Toussaint
- Faculty of Medicine, CNRS, Grenoble INP, CHU Grenoble-Alpes, University Grenoble Alpes, TIMC (UMR5525), 38000 Grenoble, France; (C.C.); (C.P.); (G.M.); (A.-R.T.); (S.T.); (B.T.)
- Service de Biochimie Biologie Moléculaire Toxicologie Environnementale, UM Biochimie des Enzymes et des Protéines, Institut de Biologie et Pathologie, CHU Grenoble-Alpes, 38000 Grenoble, France
- Plateforme de Métabolomique GEMELI-GExiM, Institut de Biologie et Pathologie, CHU Grenoble-Alpes, 38000 Grenoble, France;
| | - Dalil Hannani
- Faculty of Medicine, CNRS, Grenoble INP, CHU Grenoble-Alpes, University Grenoble Alpes, TIMC (UMR5525), 38000 Grenoble, France; (C.C.); (C.P.); (G.M.); (A.-R.T.); (S.T.); (B.T.)
| | - Audrey Le Gouellec
- Faculty of Medicine, CNRS, Grenoble INP, CHU Grenoble-Alpes, University Grenoble Alpes, TIMC (UMR5525), 38000 Grenoble, France; (C.C.); (C.P.); (G.M.); (A.-R.T.); (S.T.); (B.T.)
- Service de Biochimie Biologie Moléculaire Toxicologie Environnementale, UM Biochimie des Enzymes et des Protéines, Institut de Biologie et Pathologie, CHU Grenoble-Alpes, 38000 Grenoble, France
- Plateforme de Métabolomique GEMELI-GExiM, Institut de Biologie et Pathologie, CHU Grenoble-Alpes, 38000 Grenoble, France;
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Stojanović I, Saksida T, Miljković Đ, Pejnović N. Modulation of Intestinal ILC3 for the Treatment of Type 1 Diabetes. Front Immunol 2021; 12:653560. [PMID: 34149694 PMCID: PMC8209467 DOI: 10.3389/fimmu.2021.653560] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 05/18/2021] [Indexed: 11/22/2022] Open
Abstract
Gut-associated lymphoid tissue (GALT) is crucial for the maintenance of the intestinal homeostasis, but it is also the potential site of the activation of autoreactive cells and initiation/propagation of autoimmune diseases in the gut and in the distant organs. Type 3 innate lymphoid cells (ILC3) residing in the GALT integrate signals from food ingredients and gut microbiota metabolites in order to control local immunoreactivity. Notably, ILC3 secrete IL-17 and GM-CSF that activate immune cells in combating potentially pathogenic microorganisms. ILC3 also produce IL-22 that potentiates the strength and integrity of epithelial tight junctions, production of mucus and antimicrobial peptides thus enabling the proper function of the intestinal barrier. The newly discovered function of small intestine ILC3 is the secretion of IL-2 and the promotion of regulatory T cell (Treg) generation and function. Since the intestinal barrier dysfunction, together with the reduction in small intestine ILC3 and Treg numbers are associated with the pathogenesis of type 1 diabetes (T1D), the focus of this article is intestinal ILC3 modulation for the therapy of T1D. Of particular interest is free fatty acids receptor 2 (FFAR2), predominantly expressed on intestinal ILC3, that can be stimulated by available selective synthetic agonists. Thus, we propose that FFAR2-based interventions by boosting ILC3 beneficial functions may attenuate autoimmune response against pancreatic β cells during T1D. Also, it is our opinion that treatments based on ILC3 stimulation by functional foods can be used as prophylaxis in individuals that are genetically predisposed to develop T1D.
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Affiliation(s)
- Ivana Stojanović
- Department of Immunology, Institute for Biological Research "Siniša Stanković" - National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Tamara Saksida
- Department of Immunology, Institute for Biological Research "Siniša Stanković" - National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Đorđe Miljković
- Department of Immunology, Institute for Biological Research "Siniša Stanković" - National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Nada Pejnović
- Department of Immunology, Institute for Biological Research "Siniša Stanković" - National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia
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30
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Wagner C, Torow N, Hornef MW, Lelouard H. Spatial and temporal key steps in early-life intestinal immune system development and education. FEBS J 2021; 289:4731-4757. [PMID: 34076962 DOI: 10.1111/febs.16047] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 04/15/2021] [Accepted: 06/01/2021] [Indexed: 12/15/2022]
Abstract
Education of our intestinal immune system early in life strongly influences adult health. This education strongly relies on series of events that must occur in well-defined time windows. From initial colonization by maternal-derived microbiota during delivery to dietary changes from mother's milk to solid foods at weaning, these early-life events have indeed long-standing consequences on our immunity, facilitating tolerance to environmental exposures or, on the contrary, increasing the risk of developing noncommunicable diseases such as allergies, asthma, obesity, and inflammatory bowel diseases. In this review, we provide an outline of the recent advances in our understanding of these events and how they are mechanistically related to intestinal immunity development and education. First, we review the susceptibility of neonates to infections and inflammatory diseases, related to their immune system and microbiota changes. Then, we highlight the maternal factors involved in protection and education of the mucosal immune system of the offspring, the role of the microbiota, and the nature of neonatal immune system until weaning. We also present how the development of some immune responses is intertwined in temporal and spatial windows of opportunity. Finally, we discuss pending questions regarding the neonate particular immune status and the activation of the intestinal immune system at weaning.
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Affiliation(s)
- Camille Wagner
- Aix Marseille Univ, CNRS, INSERM, CIML, Marseille, France
| | - Natalia Torow
- Institute of Medical Microbiology, RWTH University Hospital, Aachen, Germany
| | - Mathias W Hornef
- Institute of Medical Microbiology, RWTH University Hospital, Aachen, Germany
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31
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Shi Z, Ohno H, Satoh-Takayama N. Dietary Derived Micronutrients Modulate Immune Responses Through Innate Lymphoid Cells. Front Immunol 2021; 12:670632. [PMID: 33995407 PMCID: PMC8116705 DOI: 10.3389/fimmu.2021.670632] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Accepted: 04/06/2021] [Indexed: 12/12/2022] Open
Abstract
Innate lymphoid cells (ILCs) are a group of innate immune cells that possess overlapping features with T cells, although they lack antigen-specific receptors. ILCs consist of five subsets-ILC1, ILC2, ILC3, lymphoid tissue inducer (LTi-like) cells, and natural killer (NK) cells. They have significant functions in mediating various immune responses, protecting mucosal barrier integrity and maintaining tissue homeostasis in the lung, skin, intestines, and liver. ILCs react immediately to signals from internal and external sources. Emerging evidence has revealed that dietary micronutrients, such as various vitamins and minerals can significantly modulate immune responses through ILCs and subsequently affect human health. It has been demonstrated that micronutrients control the development and proliferation of different types of ILCs. They are also potent immunoregulators in several autoimmune diseases and play vital roles in resolving local inflammation. Here, we summarize the interplay between several essential micronutrients and ILCs to maintain epithelial barrier functions in various mucosal tissues and discuss their limitations and potentials for promoting human health.
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Affiliation(s)
- Zhengzheng Shi
- Laboratory for Intestinal Ecosystem, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan.,Laboratory for Immune Regulation, Graduate School of Medical and Pharmaceutical Sciences, Chiba University, Chiba, Japan
| | - Hiroshi Ohno
- Laboratory for Intestinal Ecosystem, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan.,Laboratory for Immune Regulation, Graduate School of Medical and Pharmaceutical Sciences, Chiba University, Chiba, Japan.,Immunobiology Laboratory, Graduate School of Medical Life Science, Yokohama City University, Yokohama, Japan.,Intestinal Microbiota Project, Kanagawa Institute of Industrial Science and Technology, Kawasaki, Japan
| | - Naoko Satoh-Takayama
- Laboratory for Intestinal Ecosystem, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan.,Immunobiology Laboratory, Graduate School of Medical Life Science, Yokohama City University, Yokohama, Japan
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32
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Miljković Đ, Jevtić B, Stojanović I, Dimitrijević M. ILC3, a Central Innate Immune Component of the Gut-Brain Axis in Multiple Sclerosis. Front Immunol 2021; 12:657622. [PMID: 33912185 PMCID: PMC8071931 DOI: 10.3389/fimmu.2021.657622] [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: 01/23/2021] [Accepted: 03/15/2021] [Indexed: 12/12/2022] Open
Abstract
Gut immune cells have been increasingly appreciated as important players in the central nervous system (CNS) autoimmunity in animal models of multiple sclerosis (MS). Among the gut immune cells, innate lymphoid cell type 3 (ILC3) is of special interest in MS research, as they represent the innate cell counterpart of the major pathogenic cell population in MS, i.e. T helper (Th)17 cells. Importantly, these cells have been shown to stimulate regulatory T cells (Treg) and to counteract pathogenic Th17 cells in animal models of autoimmune diseases. Besides, they are also well known for their ability to stabilize the intestinal barrier and to shape the immune response to the gut microbiota. Thus, proper maintenance of the intestinal barrier and the establishment of the regulatory milieu in the gut performed by ILC3 may prevent activation of CNS antigen-specific Th17 cells by the molecular mimicry. Recent findings on the role of ILC3 in the gut-CNS axis and their relevance for MS pathogenesis will be discussed in this paper. Possibilities of ILC3 functional modulation for the benefit of MS patients will be addressed, as well.
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Affiliation(s)
- Đorđe Miljković
- Department of Immunology, Institute for Biological Research "Siniša Stanković" - National Institute of Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Bojan Jevtić
- Department of Immunology, Institute for Biological Research "Siniša Stanković" - National Institute of Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Ivana Stojanović
- Department of Immunology, Institute for Biological Research "Siniša Stanković" - National Institute of Republic of Serbia, University of Belgrade, Belgrade, Serbia
| | - Mirjana Dimitrijević
- Department of Immunology, Institute for Biological Research "Siniša Stanković" - National Institute of Republic of Serbia, University of Belgrade, Belgrade, Serbia
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33
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Mamareli P, Kruse F, Lu CW, Guderian M, Floess S, Rox K, Allan DSJ, Carlyle JR, Brönstrup M, Müller R, Berod L, Sparwasser T, Lochner M. Targeting cellular fatty acid synthesis limits T helper and innate lymphoid cell function during intestinal inflammation and infection. Mucosal Immunol 2021; 14:164-176. [PMID: 32355319 DOI: 10.1038/s41385-020-0285-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 03/13/2020] [Accepted: 03/24/2020] [Indexed: 02/04/2023]
Abstract
CD4+ T cells contribute critically to a protective immune response during intestinal infections, but have also been implicated in the aggravation of intestinal inflammatory pathology. Previous studies suggested that T helper type (Th)1 and Th17 cells depend on de novo fatty acid (FA) synthesis for their development and effector function. Here, we report that T-cell-specific targeting of the enzyme acetyl-CoA carboxylase 1 (ACC1), a major checkpoint controlling FA synthesis, impaired intestinal Th1 and Th17 responses by limiting CD4+ T-cell expansion and infiltration into the lamina propria in murine models of colitis and infection-associated intestinal inflammation. Importantly, pharmacological inhibition of ACC1 by the natural compound soraphen A mirrored the anti-inflammatory effects of T-cell-specific targeting, but also enhanced susceptibility toward infection with C. rodentium. Further analysis revealed that deletion of ACC1 in RORγt+ innate lymphoid cells (ILC), but not dendritic cells or macrophages, decreased resistance to infection by interfering with IL-22 production and intestinal barrier function. Together, our study suggests pharmacological targeting of ACC1 as an effective approach for metabolic immune modulation of T-cell-driven intestinal inflammatory responses, but also reveals an important role of ACC1-mediated lipogenesis for the function of RORγt+ ILC.
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Affiliation(s)
- Panagiota Mamareli
- Institute of Infection Immunology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Germany.,Institute of Medical Microbiology and Hygiene, University Medical Center, Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Friederike Kruse
- Institute of Infection Immunology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Germany
| | - Chia-Wen Lu
- Institute of Infection Immunology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Germany.,Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Hannover, Germany
| | - Melanie Guderian
- Institute of Infection Immunology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Germany.,Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Hannover, Germany
| | - Stefan Floess
- Department of Experimental Immunology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Katharina Rox
- Department of Chemical Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany.,German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, Braunschweig, Germany
| | - David S J Allan
- Department of Immunology, University of Toronto, Toronto, ON, Canada
| | - James R Carlyle
- Department of Immunology, University of Toronto, Toronto, ON, Canada
| | - Mark Brönstrup
- Department of Chemical Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Rolf Müller
- Helmholtz Institute for Pharmaceutical Research, Helmholtz Centre for Infection Research, Saarland University, Saarbrücken, Germany.,Department of Pharmaceutical Biotechnology, Saarland University, Saarbrücken, Germany
| | - Luciana Berod
- Institute of Infection Immunology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Germany
| | - Tim Sparwasser
- Institute of Infection Immunology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Germany.,Institute of Medical Microbiology and Hygiene, University Medical Center, Johannes Gutenberg-University Mainz, Mainz, Germany
| | - Matthias Lochner
- Institute of Infection Immunology, TWINCORE, Centre for Experimental and Clinical Infection Research, Hannover, Germany. .,Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School, Hannover, Germany.
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Vitamin A deficiency increases the risk of gastrointestinal comorbidity and exacerbates core symptoms in children with autism spectrum disorder. Pediatr Res 2021; 89:211-216. [PMID: 32225174 DOI: 10.1038/s41390-020-0865-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 02/20/2020] [Accepted: 02/24/2020] [Indexed: 11/09/2022]
Abstract
BACKGROUND Autism spectrum disorder (ASD) is a neurodevelopmental disorder, and many individuals with ASD have gastrointestinal (GI) comorbidities. Vitamin A (VA) is an essential micronutrient that plays an important role in brain development and GI function. METHODS A total of 323 children with ASD and 180 control children were enrolled in this study. Symptoms of ASD were assessed with the Child Autism Rating Scale (CARS), the Social Responsiveness Scale (SRS), and the Autism Behavior Checklist (ABC). Caregivers of the children completed questionnaires about GI symptoms. Serum retinol levels were detected with high-performance liquid chromatography (HPLC). RESULTS Children with ASD and with GI comorbidity and constipation had considerably lower serum VA levels than autistic children without these symptoms. VA level was associated with CARS, SRS, and ABC scores, whereas GI symptoms were associated some SRS and ABC scores. The interaction of VAD and GI symptoms appeared to aggravate some of the core symptoms of children with ASD. CONCLUSIONS VAD exacerbates core symptoms in children with ASD, and ASD children with GI comorbidities also have more serious core symptoms than ASD children without GI comorbidities. VAD comorbid with GI symptoms aggravates autistic children's core symptoms. IMPACT VAD exacerbates core symptoms in children with ASD. ASD children with GI comorbidities have more serious core symptoms than ASD children without GI comorbidities. VAD comorbid with GI symptoms aggravates autistic children's core symptoms. We speculate that VAD might be related to a subtype of ASD that involves GI comorbidities. We believe that our findings will be of fundamental importance to the scientific community.
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Midha IK, Kumar N, Kumar A, Madan T. Mega doses of retinol: A possible immunomodulation in Covid-19 illness in resource-limited settings. Rev Med Virol 2020; 31:1-14. [PMID: 33382930 PMCID: PMC7883262 DOI: 10.1002/rmv.2204] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 11/30/2020] [Accepted: 12/01/2020] [Indexed: 12/13/2022]
Abstract
Of all the nutrients, vitamin A has been the most extensively evaluated for its impact on immunity. There are three main forms of vitamin A, retinol, retinal and retinoic acid (RA) with the latter being most biologically active and all‐trans‐RA (ATRA) its main derivative. Vitamin A is a key regulator of the functions of various innate and adaptive immune cells and promotes immune‐homeostasis. Importantly, it augments the interferon‐based innate immune response to RNA viruses decreasing RNA virus replication. Several clinical trials report decreased mortality in measles and Ebola with vitamin A supplementation.During the Covid‐19 pandemic interventions such as convalescent plasma, antivirals, monoclonal antibodies and immunomodulator drugs have been tried but most of them are difficult to implement in resource‐limited settings. The current review explores the possibility of mega dose vitamin A as an affordable adjunct therapy for Covid‐19 illness with minimal reversible side effects. Insight is provided into the effect of vitamin A on ACE‐2 expression in the respiratory tract and its association with the prognosis of Covid‐19 patients. Vitamin A supplementation may aid the generation of protective immune response to Covid‐19 vaccines. An overview of the dosage and safety profile of vitamin A is presented along with recommended doses for prophylactic/therapeutic use in randomised controlled trials in Covid‐19 patients.
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Affiliation(s)
| | - Nilesh Kumar
- Saint Vincent Hospital, Worcester, Massachusetts, USA
| | - Amit Kumar
- Dwight D. Eisenhower VA Medical Center, Leavenworth, Kansas, USA
| | - Taruna Madan
- Department of Innate Immunity, ICMR-National Institute for Research in Reproductive Health, Mumbai, India
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Xian Y, Lv X, Xie M, Xiao F, Kong C, Ren Y. Physiological function and regulatory signal of intestinal type 3 innate lymphoid cell(s). Life Sci 2020; 262:118504. [PMID: 32991877 DOI: 10.1016/j.lfs.2020.118504] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Revised: 09/19/2020] [Accepted: 09/23/2020] [Indexed: 02/07/2023]
Abstract
Of the three groups of innate lymphoid cells, the type 3 innate lymphoid cell(s) (ILC3) include the subgroup of enteric ILC3 that participates in many physiological functions of the organism, such as promoting the repair of damaged mucosa, maintaining the homeostasis of gut symbiotic microorganisms, and presenting specific antigens. ILC3 also includes splenic and decidual ILC3. Like other physiological processes in the organism, enteric ILC3 functions are precisely regulated at the endogenous and exogenous levels. However, there has been no review on the physiological functions and regulatory signals of intestinal ILC3. In this paper, based on the current research on the physiological functions of enteric ILC3 in animals and the human, we summarize the signals that regulate cytokine secretion, antigen presentation and the quantity of ILC3 under normal intestinal conditions. We discuss for the first time the classification of the promoting mechanism of secretagogues of ILC3 into direct and indirect types. We also propose that ILC3 can promote intestinal homeostasis, and intestinal homeostasis can ensure the physiological phenotype of ILC3. If homeostasis is disturbed, ILC3 may participate in intestinal pathological changes. Therefore, regulating ILC3 and maintaining intestinal homeostasis are critical to the body.
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Affiliation(s)
- Yin Xian
- Department of General Surgery, and Institute of Hepato-Biliary-Pancreas and Intestinal Disease, Affiliated Hospital of North Sichuan Medical College, Nanchong 637000, PR China
| | - Xiaodong Lv
- Department of General Surgery, and Institute of Hepato-Biliary-Pancreas and Intestinal Disease, Affiliated Hospital of North Sichuan Medical College, Nanchong 637000, PR China
| | - Minjia Xie
- School of Clinical Medicine, North Sichuan Medical College, Nanchong 637000, PR China
| | - Fuyang Xiao
- School of Clinical Medicine, North Sichuan Medical College, Nanchong 637000, PR China
| | - Chenyang Kong
- School of Clinical Medicine, North Sichuan Medical College, Nanchong 637000, PR China
| | - Yixing Ren
- Department of General Surgery, and Institute of Hepato-Biliary-Pancreas and Intestinal Disease, Affiliated Hospital of North Sichuan Medical College, Nanchong 637000, PR China.
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Song D, Lai L, Ran Z. Metabolic Regulation of Group 3 Innate Lymphoid Cells and Their Role in Inflammatory Bowel Disease. Front Immunol 2020; 11:580467. [PMID: 33193381 PMCID: PMC7649203 DOI: 10.3389/fimmu.2020.580467] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 09/30/2020] [Indexed: 12/16/2022] Open
Abstract
Inflammatory bowel disease (IBD) is characterized by chronic and relapsing inflammatory disorder of the intestine. IBD is associated with complex pathogenesis, and considerable data suggest that innate lymphoid cells contribute to the development and progression of the condition. Group 3 innate lymphoid cells (ILC3s) not only play a protective role in maintaining intestinal homeostasis and gut barrier function, but also a pathogenic role in intestinal inflammation. ILC3s can sense environmental and host-derived signals and combine these cues to modulate cell expansion, migration and function, and transmit information to the broader immune system. Herein, we review current knowledge of how ILC3s can be regulated by dietary nutrients, microbiota and their metabolites, as well as other metabolites. In addition, we describe the phenotypic and functional alterations of ILC3s in IBD and discuss the therapeutic potential of ILC3s in the treatment of IBD.
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Affiliation(s)
- Dongjuan Song
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, Inflammatory Bowel Disease Research Center, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Institute of Digestive Disease, Shanghai, China
| | - Lijie Lai
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, Inflammatory Bowel Disease Research Center, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Institute of Digestive Disease, Shanghai, China
| | - Zhihua Ran
- Division of Gastroenterology and Hepatology, Key Laboratory of Gastroenterology and Hepatology, Ministry of Health, Inflammatory Bowel Disease Research Center, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai Institute of Digestive Disease, Shanghai, China
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Innate Lymphoid Cells: Important Regulators of Host-Bacteria Interaction for Border Defense. Microorganisms 2020; 8:microorganisms8091342. [PMID: 32887435 PMCID: PMC7563982 DOI: 10.3390/microorganisms8091342] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 08/29/2020] [Accepted: 08/31/2020] [Indexed: 12/12/2022] Open
Abstract
Innate lymphoid cells (ILCs) are a recently discovered type of innate immune lymphocyte. They include three different groups classified by the nature of the transcription factors required for their development and by the cytokines they produce. ILCs mainly reside in tissues close to the mucosal barrier such as the respiratory and gastrointestinal tracts. Due to their close proximity to the mucosal surface, ILCs are exposed to a variety of both commensal and pathogenic bacteria. Under non-pathological conditions, ILCs have been shown to be important regulators for the maintenance of tissue homeostasis by mutual interactions with the microbiome. Besides these important functions at homeostasis, several studies have also provided emerging evidence that ILCs contribute to defense against pathogenic bacterial infection by responding rapidly to the pathogens as well as orchestrating other immune cells. In this review, we summarize recent advances in our understanding of the interactions of ILCs and bacteria, with special focus on the function of the different ILC subsets in bacterial infections.
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39
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Zhou W, Sonnenberg GF. Activation and Suppression of Group 3 Innate Lymphoid Cells in the Gut. Trends Immunol 2020; 41:721-733. [PMID: 32646594 PMCID: PMC7395873 DOI: 10.1016/j.it.2020.06.009] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 06/15/2020] [Accepted: 06/15/2020] [Indexed: 12/12/2022]
Abstract
Group 3 innate lymphoid cells (ILC3s) have emerged as master regulators of intestinal health and tissue homeostasis in mammals. Through a diverse array of cytokines and cellular interactions, ILC3s crucially orchestrate lymphoid organogenesis, promote tissue protection or regeneration, facilitate antimicrobial responses, and directly regulate adaptive immunity. Further, translational studies have found that ILC3 responses are altered in the intestine of defined patient populations with chronic infectious, inflammatory, or metabolic diseases. Therefore, it is essential to broadly understand the signals that activate, suppress, or fine-tune ILC3s in the gut. Here, we discuss recent exciting advances in this field, integrate them into our current understanding of ILC3 biology, and highlight fundamental gaps in knowledge that require additional investigation.
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Affiliation(s)
- Wenqing Zhou
- Joan and Sanford I. Weill Department of Medicine, Division of Gastroenterology, Weill Cornell Medicine, Cornell University, New York, NY, USA; Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, New York, NY, USA; Jill Roberts Institute for Research in Inflammatory Bowel Disease, Weill Cornell Medicine, Cornell University, New York, NY, USA
| | - Gregory F Sonnenberg
- Joan and Sanford I. Weill Department of Medicine, Division of Gastroenterology, Weill Cornell Medicine, Cornell University, New York, NY, USA; Department of Microbiology and Immunology, Weill Cornell Medicine, Cornell University, New York, NY, USA; Jill Roberts Institute for Research in Inflammatory Bowel Disease, Weill Cornell Medicine, Cornell University, New York, NY, USA.
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40
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Iyer N, Grizotte-Lake M, Duncan K, Gordon SR, Palmer ACS, Calvin C, Zhong G, Isoherranen N, Vaishnava S. Epithelium intrinsic vitamin A signaling co-ordinates pathogen clearance in the gut via IL-18. PLoS Pathog 2020; 16:e1008360. [PMID: 32330185 PMCID: PMC7202665 DOI: 10.1371/journal.ppat.1008360] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 05/06/2020] [Accepted: 01/27/2020] [Indexed: 01/17/2023] Open
Abstract
Intestinal epithelial cells (IECs) are at the forefront of host-pathogen interactions, coordinating a cascade of immune responses to protect against pathogens. Here we show that IEC-intrinsic vitamin A signaling restricts pathogen invasion early in the infection and subsequently activates immune cells to promote pathogen clearance. Mice blocked for retinoic acid receptor (RAR) signaling selectively in IECs (stopΔIEC) showed higher Salmonella burden in colonic tissues early in the infection that associated with higher luminal and systemic loads of the pathogen at later stages. Higher pathogen burden in stopΔIEC mice correlated with attenuated mucosal interferon gamma (IFNγ) production by underlying immune cells. We found that, at homeostasis, the intestinal epithelium of stopΔIEC mice produced significantly lower amounts of interleukin 18 (IL-18), a potent inducer of IFNγ. Regulation of IL-18 by vitamin A was also observed in a dietary model of vitamin A supplementation. IL-18 reconstitution in stopΔIEC mice restored resistance to Salmonella by promoting epithelial cell shedding to eliminate infected cells and limit pathogen invasion early in infection. Further, IL-18 augmented IFNγ production by underlying immune cells to restrict pathogen burden and systemic spread. Our work uncovers a critical role for vitamin A in coordinating a biphasic immune response to Salmonella infection by regulating IL-18 production by IECs. Epithelial cells line the intestinal lumen, forming a barrier between the body and dietary and microbial contents in the lumen. Apart from absorbing nutrients from diet, these epithelial cells help mediate a stable, symbiotic relationship between commensal bacteria and the immune cells. During infection, they help co-ordinate the immune response to counter the infection. How dietary micronutrients, such as vitamin A, inform epithelial cell function during infection is poorly understood. Using a model where epithelial cells in the gut cannot respond to vitamin A signals, we find that epithelial vitamin A signaling promotes resistance to Salmonella infection. We show that, vitamin A increases the production of a key cytokine, interleukin 18, by epithelial cells. IL-18 promotes shedding of infected epithelial cells to reduce the pathogen invasion while also inducing the production of interferon gamma by immune cells to mediate pathogen clearance. Thus, epithelial cells dynamically respond to dietary vitamin A to regulate interleukin 18 production and potentiate resistance to infection.
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Affiliation(s)
- Namrata Iyer
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, United States of America
| | - Mayara Grizotte-Lake
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, United States of America
| | - Kellyanne Duncan
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, United States of America
| | - Sarah R. Gordon
- Department of Molecular Biology, Cell Biology and Biochemistry, Brown University, Providence, RI, United States of America
| | - Ana C. S. Palmer
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, United States of America
| | - Crystle Calvin
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, United States of America
| | - Guo Zhong
- Department of Pharmaceutics, University of Washington, Seattle, WA, United States of America
| | - Nina Isoherranen
- Department of Pharmaceutics, University of Washington, Seattle, WA, United States of America
| | - Shipra Vaishnava
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI, United States of America
- * E-mail:
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41
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Abidi A, Laurent T, Bériou G, Bouchet-Delbos L, Fourgeux C, Louvet C, Triki-Marrakchi R, Poschmann J, Josien R, Martin J. Characterization of Rat ILCs Reveals ILC2 as the Dominant Intestinal Subset. Front Immunol 2020; 11:255. [PMID: 32140157 PMCID: PMC7043102 DOI: 10.3389/fimmu.2020.00255] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2019] [Accepted: 01/30/2020] [Indexed: 12/17/2022] Open
Abstract
Innate lymphoid cells (ILCs) are tissue-resident lymphocytes that lack antigen-specific receptors and exhibit innate effector functions such as cytokine production that play an important role in immediate responses to pathogens especially at mucosal sites. Mouse and human ILC subsets have been extensively characterized in various tissues and in blood. In this study, we present the first characterization of ILCs and ILC subsets in rat gut and secondary lymphoid organs using flow cytometry and single cell RNA sequencing. Our results show that phenotype and function of rat ILC subsets are conserved as compared to human and mouse ILCs. However, and in contrast to human and mouse, our study unexpectedly revealed that ILC2 and not ILC3 was the dominant ILC subset in the rat intestinal lamina propria. ILC2 predominance in the gut was independent of rat strain, sex or housing facility. In contrast, ILC3 was the predominant ILC subset in mesenteric lymph nodes and Peyer patches. In conclusion, our study demonstrates that in spite of highly conserved phenotype and function between mice, rat and humans, the distribution of ILC subsets in the intestinal mucosa is dependent on the species likely in response to both genetic and environmental factors.
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Affiliation(s)
- Ahmed Abidi
- Université de Nantes, Inserm, CHU Nantes, Centre de Recherche en Transplantation et Immunologie, UMR 1064, ITUN, Nantes, France.,Université de Tunis El Manar, Laboratoire de Génétique, Immunologie et Pathologies Humaines, Faculté des Sciences de Tunis, Tunis, Tunisia
| | - Thomas Laurent
- Université de Nantes, Inserm, CHU Nantes, Centre de Recherche en Transplantation et Immunologie, UMR 1064, ITUN, Nantes, France
| | - Gaëlle Bériou
- Université de Nantes, Inserm, CHU Nantes, Centre de Recherche en Transplantation et Immunologie, UMR 1064, ITUN, Nantes, France
| | - Laurence Bouchet-Delbos
- Université de Nantes, Inserm, CHU Nantes, Centre de Recherche en Transplantation et Immunologie, UMR 1064, ITUN, Nantes, France
| | - Cynthia Fourgeux
- Université de Nantes, Inserm, CHU Nantes, Centre de Recherche en Transplantation et Immunologie, UMR 1064, ITUN, Nantes, France
| | - Cédric Louvet
- Université de Nantes, Inserm, CHU Nantes, Centre de Recherche en Transplantation et Immunologie, UMR 1064, ITUN, Nantes, France
| | - Raja Triki-Marrakchi
- Université de Tunis El Manar, Laboratoire de Génétique, Immunologie et Pathologies Humaines, Faculté des Sciences de Tunis, Tunis, Tunisia
| | - Jeremie Poschmann
- Université de Nantes, Inserm, CHU Nantes, Centre de Recherche en Transplantation et Immunologie, UMR 1064, ITUN, Nantes, France
| | - Régis Josien
- Université de Nantes, Inserm, CHU Nantes, Centre de Recherche en Transplantation et Immunologie, UMR 1064, ITUN, Nantes, France.,CHU Nantes, Laboratoire d'Immunologie, Nantes, France
| | - Jérôme Martin
- Université de Nantes, Inserm, CHU Nantes, Centre de Recherche en Transplantation et Immunologie, UMR 1064, ITUN, Nantes, France.,CHU Nantes, Laboratoire d'Immunologie, Nantes, France
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42
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Domingues RG, Hepworth MR. Immunoregulatory Sensory Circuits in Group 3 Innate Lymphoid Cell (ILC3) Function and Tissue Homeostasis. Front Immunol 2020; 11:116. [PMID: 32117267 PMCID: PMC7015949 DOI: 10.3389/fimmu.2020.00116] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 01/16/2020] [Indexed: 12/12/2022] Open
Abstract
Recent years have seen a revolution in our understanding of how cells of the immune system are modulated and regulated not only via complex interactions with other immune cells, but also through a range of potent inputs derived from diverse and varied biological systems. Within complex tissue environments, such as the gastrointestinal tract and lung, these systems act to orchestrate and temporally align immune responses, regulate cellular function, and ensure tissue homeostasis and protective immunity. Group 3 Innate Lymphoid Cells (ILC3s) are key sentinels of barrier tissue homeostasis and critical regulators of host-commensal mutualism—and respond rapidly to damage, inflammation and infection to restore tissue health. Recent findings place ILC3s as strategic integrators of environmental signals. As a consequence, ILC3s are ideally positioned to detect perturbations in cues derived from the environment—such as the diet and microbiota—as well as signals produced by the host nervous, endocrine and circadian systems. Together these cues act in concert to induce ILC3 effector function, and form critical sensory circuits that continually function to reinforce tissue homeostasis. In this review we will take a holistic, organismal view of ILC3 biology and explore the tissue sensory circuits that regulate ILC3 function and align ILC3 responses with changes within the intestinal environment.
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Affiliation(s)
- Rita G Domingues
- Division of Infection, Immunity and Respiratory Medicine, Faculty of Biology, Medicine and Health, Manchester Collaborative Centre for Inflammation Research, Lydia Becker Institute of Immunology and Inflammation, Manchester Academic Health Science Centre, The University of Manchester, Manchester, United Kingdom
| | - Matthew R Hepworth
- Division of Infection, Immunity and Respiratory Medicine, Faculty of Biology, Medicine and Health, Manchester Collaborative Centre for Inflammation Research, Lydia Becker Institute of Immunology and Inflammation, Manchester Academic Health Science Centre, The University of Manchester, Manchester, United Kingdom
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43
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Anatomical Uniqueness of the Mucosal Immune System (GALT, NALT, iBALT) for the Induction and Regulation of Mucosal Immunity and Tolerance. MUCOSAL VACCINES 2020. [PMCID: PMC7149644 DOI: 10.1016/b978-0-12-811924-2.00002-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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44
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Willinger T. Metabolic Control of Innate Lymphoid Cell Migration. Front Immunol 2019; 10:2010. [PMID: 31507605 PMCID: PMC6713999 DOI: 10.3389/fimmu.2019.02010] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Accepted: 08/08/2019] [Indexed: 12/24/2022] Open
Abstract
Innate lymphoid cells (ILCs) are specialized immune cells that rapidly respond to environmental challenges, such as infection and tissue damage. ILCs play an important role in organ homeostasis, tissue repair, and host defense in the mucosal tissues intestine and lung. ILCs are sentinels of healthy tissue function, yet it is poorly understood how ILCs are recruited, strategically positioned, and maintained within tissues. Accordingly, ILC migration is an area that has recently come into focus and it is important to define the signals that control ILC migration to and within tissues. In this context, signals from the local tissue microenvironment are relevant. For example, ILCs in the intestine are exposed to an environment that is rich in dietary, microbial, and endogenous metabolites. It has been shown that the Vitamin A metabolite retinoic acid promotes ILC1 and ILC3 homing to the intestine. In addition, recent studies have discovered cholesterol metabolites (oxysterols) as a novel class of molecules that regulate ILC migration through the receptor GPR183. ILCs are considered to be largely tissue-resident cells, yet recent data indicate that ILCs actively migrate during inflammation. Furthermore, the discovery of circulating ILC precursors in humans and their presence within tissues has fueled the concept of local ILC-poiesis. However, it is unclear how circulating ILCs enter tissue during embryogenesis and inflammation and how they are directed to local tissue niches. In this review, I will discuss the metabolic signals that regulate ILC homing and their strategic positioning in healthy and inflamed tissues. It is becoming increasingly clear that ILC function is closely linked to their tissue localization. Therefore, understanding the tissue signals that control ILC migration could open new avenues for the treatment of chronic inflammatory diseases and cancer.
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Affiliation(s)
- Tim Willinger
- Department of Medicine Huddinge, Center for Infectious Medicine, Karolinska Institutet, Stockholm, Sweden
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45
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Bourke CD, Jones KDJ, Prendergast AJ. Current Understanding of Innate Immune Cell Dysfunction in Childhood Undernutrition. Front Immunol 2019; 10:1728. [PMID: 31417545 PMCID: PMC6681674 DOI: 10.3389/fimmu.2019.01728] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 07/09/2019] [Indexed: 12/13/2022] Open
Abstract
Undernutrition affects millions of children in low- and middle-income countries (LMIC) and underlies almost half of all deaths among children under 5 years old. The growth deficits that characterize childhood undernutrition (stunting and wasting) result from simultaneous underlying defects in multiple physiological processes, and current treatment regimens do not completely normalize these pathways. Most deaths among undernourished children are due to infections, indicating that their anti-pathogen immune responses are impaired. Defects in the body's first-line-of-defense against pathogens, the innate immune system, is a plausible yet understudied pathway that could contribute to this increased infection risk. In this review, we discuss the evidence for innate immune cell dysfunction from cohort studies of childhood undernutrition in LMIC, highlighting knowledge gaps in almost all innate immune cell types. We supplement these gaps with insights from relevant experimental models and make recommendations for how human and animal studies could be improved. A better understanding of innate immune function could inform future tractable immune-targeted interventions for childhood undernutrition to reduce mortality and improve long-term health, growth and development.
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Affiliation(s)
- Claire D Bourke
- Centre for Genomics & Child Health, Blizard Institute, Queen Mary University of London, London, United Kingdom.,Zvitambo Institute for Maternal and Child Health Research, Harare, Zimbabwe
| | - Kelsey D J Jones
- Kennedy Institute for Rheumatology, University of Oxford, Oxford, United Kingdom.,Department of Paediatric Gastroenterology & Nutrition, University of Oxford NHS Foundation Trust, Oxford, United Kingdom
| | - Andrew J Prendergast
- Centre for Genomics & Child Health, Blizard Institute, Queen Mary University of London, London, United Kingdom.,Zvitambo Institute for Maternal and Child Health Research, Harare, Zimbabwe
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46
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Branzk N, Gronke K, Diefenbach A. Innate lymphoid cells, mediators of tissue homeostasis, adaptation and disease tolerance. Immunol Rev 2019; 286:86-101. [PMID: 30294961 DOI: 10.1111/imr.12718] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 09/05/2018] [Indexed: 02/06/2023]
Abstract
Innate lymphoid cells (ILC) are a recently identified group of tissue-resident innate lymphocytes. Available data support the view that ILC or their progenitors are deposited and retained in tissues early during ontogeny. Thereby, ILC become an integral cellular component of tissues and organs. Here, we will review the intriguing relationships between ILC and basic developmental and homeostatic processes within tissues. Studying ILC has already led to the appreciation of the integral roles of immune cells in tissue homeostasis, morphogenesis, metabolism, regeneration, and growth. This area of immunology has not yet been studied in-depth but is likely to reveal important networks contributing to disease tolerance and may be harnessed for future therapeutic approaches.
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Affiliation(s)
- Nora Branzk
- Laboratory of Innate Immunity, Department of Microbiology, Infectious Diseases and Immunology, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Berlin Institute of Health (BIH), Berlin, Germany.,Mucosal and Developmental Immunology, Deutsches Rheuma-Forschungszentrum, Berlin, Germany
| | - Konrad Gronke
- Laboratory of Innate Immunity, Department of Microbiology, Infectious Diseases and Immunology, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Berlin Institute of Health (BIH), Berlin, Germany.,Mucosal and Developmental Immunology, Deutsches Rheuma-Forschungszentrum, Berlin, Germany
| | - Andreas Diefenbach
- Laboratory of Innate Immunity, Department of Microbiology, Infectious Diseases and Immunology, Charité - Universitätsmedizin Berlin, Berlin, Germany.,Berlin Institute of Health (BIH), Berlin, Germany.,Mucosal and Developmental Immunology, Deutsches Rheuma-Forschungszentrum, Berlin, Germany
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47
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Shao L, Pan S, Zhang QP, Jamal M, Chen LH, Yin Q, Wu YJ, Xiong J, Xiao RJ, Kwong YL, Zhou FL, Lie AKW. An Essential Role of Innate Lymphoid Cells in the Pathophysiology of Graft-vs.-Host Disease. Front Immunol 2019; 10:1233. [PMID: 31244831 PMCID: PMC6563595 DOI: 10.3389/fimmu.2019.01233] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2018] [Accepted: 05/15/2019] [Indexed: 12/14/2022] Open
Abstract
Allogeneic hematopoietic stem cell transplantation (Allo-HSCT) is the only curative treatment for multiple hematologic malignancies and non-malignant hematological diseases. However, graft-vs.-host disease (GVHD), one of the main complications after allo-HSCT, remains the major reason for morbidity and non-relapse mortality. Emerging evidence has demonstrated that innate lymphoid cells (ILCs) play a non-redundant role in the pathophysiology of GVHD. In this review, we will summarize previously published data regarding the role of ILCs in the pathogenesis of GVHD.
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Affiliation(s)
- Liang Shao
- Department of Hematology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Shan Pan
- Department of Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Qiu-Ping Zhang
- Department of Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Muhammad Jamal
- Department of Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Lu-Hua Chen
- Department of Medicine, Li Ka Shing Faculty of Medicine, Faculty of Social Sciences, The University of Hong Kong, Hong Kong, China
| | - Qian Yin
- Department of Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Ying-Jie Wu
- Department of Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Jie Xiong
- Department of Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Rui-Jing Xiao
- Department of Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, China
| | - Yok-Lam Kwong
- Division of Hematology & BMT Center, Queen Mary Hospital, Hong Kong, China
| | - Fu-Ling Zhou
- Department of Hematology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Albert K W Lie
- Division of Hematology & BMT Center, Queen Mary Hospital, Hong Kong, China
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48
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Poholek CH, Dulson SJ, Zajac AJ, Harrington LE. IL-21 Controls ILC3 Cytokine Production and Promotes a Protective Phenotype in a Mouse Model of Colitis. Immunohorizons 2019; 3:194-202. [PMID: 31356165 PMCID: PMC6788290 DOI: 10.4049/immunohorizons.1900005] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 05/14/2019] [Indexed: 01/26/2023] Open
Abstract
Group 3 innate lymphoid cells (ILC3s) have dual roles in intestinal health, acting in both protective and pathogenic capacities, and importantly, modulations in this population of innate lymphoid cells have been implicated in inflammatory bowel disease. Further, subpopulations of ILC3s have been described as serving specific functions in maintaining homeostasis or responding to infection, and aberrant activation of one or more of these subpopulations could exacerbate inflammatory bowel disease. However, the signals that enforce the protective and pathogenic features of ILC3s are not fully elucidated. In this article, we show that IL-21, a cytokine primarily produced by CD4 T cells, acts on a subpopulation of intestinal ILC3s to promote a protective phenotype. IL-21 signaling does not affect the MHC class II-expressing ILC3 subset but promotes ILC3s that express Tbet and are poised to produce IL-22. Consistent with a protective phenotype, IL-21 deficiency dampens cytokine-induced IL-17A production. We show that exacerbated colitis develops in mice lacking the IL-21 receptor, in agreement with a protective role for IL-21 signaling on ILC3s. To our knowledge, these data reveal a novel role for IL-21 in shaping innate lymphoid cell responses in the intestine and provide one mechanism by which effector CD4 T cells can influence innate immunity.
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Affiliation(s)
- Catherine H Poholek
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294; and
| | - Sarah J Dulson
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294; and
| | - Allan J Zajac
- Department of Microbiology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Laurie E Harrington
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294; and
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49
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Abstract
Cholesterol is an essential molecule for life. It is a component of the cell membrane, and it is a precursor molecule for bile acids, vitamin D and steroid hormones. Cholesterol is actively metabolized, but the impact of endogenous cholesterol metabolites on immune function, especially in the intestine, is poorly understood. In this review, I focus on oxysterols, hydroxylated forms of cholesterol, and their specialized functions in intestinal immunity. Oxysterols act through various intracellular and extracellular receptors and serve as key metabolic signals, coordinating immune activity and inflammation. Our recent work has identified an unexpected link between cholesterol metabolism, innate lymphoid cell function and intestinal homeostasis. We discovered that oxysterol sensing through the G protein-coupled receptor 183 (GPR183) directs the migration of innate lymphoid cells, which is essential for the formation of lymphoid tissue in the colon. Moreover, we found that the interaction of GPR183 with oxysterols regulates intestinal inflammation. I will discuss the therapeutic potential of oxysterols and future possibilities of treating inflammatory bowel disease through the modulation of cholesterol metabolism.
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Affiliation(s)
- T Willinger
- Department of Medicine Huddinge, Center for Infectious Medicine, Karolinska Institutet, Stockholm, Sweden
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50
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Magrone T, Jirillo E. Development and Organization of the Secondary and Tertiary Lymphoid Organs: Influence of Microbial and Food Antigens. Endocr Metab Immune Disord Drug Targets 2019; 19:128-135. [DOI: 10.2174/1871530319666181128160411] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 02/26/2018] [Accepted: 02/28/2018] [Indexed: 12/11/2022]
Abstract
Background:Secondary lymphoid organs (SLO) are distributed in many districts of the body and, especially, lymph nodes, spleen and gut-associated lymphoid tissue are the main cellular sites. On the other hand, tertiary lymphoid organs (TLO) are formed in response to inflammatory, infectious, autoimmune and neoplastic events. </P><P> Developmental Studies: In the present review, emphasis will be placed on the developmental differences of SLO and TLO between small intestine and colon and on the role played by various chemokines and cell receptors. Undoubtedly, microbiota is indispensable for the formation of SLO and its absence leads to their poor formation, thus indicating its strict interaction with immune and non immune host cells. Furthermore, food antigens (for example, tryptophan derivatives, flavonoids and byphenils) bind the aryl hydrocarbon receptor on innate lymphoid cells (ILCs), thus promoting the development of postnatal lymphoid tissues. Also retinoic acid, a metabolite of vitamin A, contributes to SLO development during embryogenesis. Vitamin A deficiency seems to account for reduction of ILCs and scarce formation of solitary lymphoid tissue. </P><P> Translational Studies: The role of lymphoid organs with special reference to intestinal TLO in the course of experimental and human disease will also be discussed. </P><P> Future Perspectives: Finally, a new methodology, the so-called “gut-in-a dish”, which has facilitated the in vitro interaction study between microbe and intestinal immune cells, will be described.
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Affiliation(s)
- Thea Magrone
- Department of Basic Medical Sciences, Neuroscience and Sensory Organs, University of Bari, School of Medicine, Bari, Italy
| | - Emilio Jirillo
- Department of Basic Medical Sciences, Neuroscience and Sensory Organs, University of Bari, School of Medicine, Bari, Italy
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