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Nature Reviews. Immunology Mar 2016The intestinal mucosa is a particularly dynamic environment in which the host constantly interacts with trillions of commensal microorganisms, known as the microbiota,... (Review)
Review
The intestinal mucosa is a particularly dynamic environment in which the host constantly interacts with trillions of commensal microorganisms, known as the microbiota, and periodically interacts with pathogens of diverse nature. In this Review, we discuss how mucosal immunity is controlled in response to enteric bacterial pathogens, with a focus on the species that cause morbidity and mortality in humans. We explain how the microbiota can shape the immune response to pathogenic bacteria, and we detail innate and adaptive immune mechanisms that drive protective immunity against these pathogens. The vast diversity of the microbiota, pathogens and immune responses encountered in the intestines precludes discussion of all of the relevant players in this Review. Instead, we aim to provide a representative overview of how the intestinal immune system responds to pathogenic bacteria.
Topics: Bacteria; Humans; Immunity, Innate; Immunity, Mucosal; Intestinal Mucosa
PubMed: 26898110
DOI: 10.1038/nri.2015.17 -
Journal of Molecular Medicine (Berlin,... Jan 2021Mucosal immunity has crucial roles in human diseases such as respiratory tract infection, inflammatory bowel diseases (IBD), and colorectal cancer (CRC). Recent studies... (Review)
Review
Mucosal immunity has crucial roles in human diseases such as respiratory tract infection, inflammatory bowel diseases (IBD), and colorectal cancer (CRC). Recent studies suggest that the mononuclear phagocyte system, cancer cells, bacteria, and viruses induce the mucosal immune reaction by various pathways, and can be major factors in the pathogenesis of these diseases. Transfer RNA (tRNA) and its fragments, including tRNA-derived RNA fragments (tRFs) and tRNA-derived stress-induced RNAs (tiRNAs), have emerged as a hot topic in recent years. They not only are verified as essential for transcription and translation but also play roles in cellular homeostasis and functions, such as cell metastasis, proliferation, and apoptosis. However, the specific relationship between their biological regulation and mucosal immunity remains unclear to date. In the present review, we carry out a comprehensive discussion on the specific roles of tRNA, tRFs, and tiRNAs relevant to mucosal immunity and related diseases.
Topics: Humans; Immunity, Mucosal; RNA, Transfer
PubMed: 33200232
DOI: 10.1007/s00109-020-02008-4 -
Frontiers in Immunology 2021
Topics: Animals; Cytokines; Humans; Immunity, Mucosal; Intestinal Mucosa
PubMed: 34054881
DOI: 10.3389/fimmu.2021.698693 -
World Journal of Gastroenterology Aug 2021As the gastrointestinal tract may also be a crucial entry or interaction site of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the role of the gut... (Review)
Review
As the gastrointestinal tract may also be a crucial entry or interaction site of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the role of the gut mucosal immune system as a first-line physical and immunological defense is critical. Furthermore, gastrointestinal involvement and symptoms in coronavirus disease 2019 (COVID-19) patients have been linked to worse clinical outcomes. This review discusses recent data on the interactions between the virus and the immune cells and molecules in the mucosa during the infection. By carrying out appropriate investigations, the mucosal immune system role in SARS-CoV-2 infection in therapy and prevention can be established. In line with this, COVID-19 vaccines that stimulate mucosal immunity against the virus may have more advantages than the others.
Topics: COVID-19; COVID-19 Vaccines; Gastrointestinal Tract; Humans; Immunity, Mucosal; Mucous Membrane; SARS-CoV-2
PubMed: 34497434
DOI: 10.3748/wjg.v27.i30.5047 -
Immunological Reviews Mar 2023Mucosal tissues are constantly exposed to the outside environment. They receive signals from the commensal microbiome and tissue-specific triggers including alimentary... (Review)
Review
Mucosal tissues are constantly exposed to the outside environment. They receive signals from the commensal microbiome and tissue-specific triggers including alimentary and airborne elements and are tasked to maintain balance in the absence of inflammation and infection. Here, we present neutrophils as sentinel cells in mucosal immunity. We discuss the roles of neutrophils in mucosal homeostasis and overview clinical susceptibilities in patients with neutrophil defects. Finally, we present concepts related to specification of neutrophil responses within specific mucosal tissue microenvironments.
Topics: Humans; Neutrophils; Immunity, Mucosal; Mucous Membrane; Inflammation; Microbiota
PubMed: 36404627
DOI: 10.1111/imr.13171 -
Internal and Emergency Medicine Sep 2023The intestinal mucosa represents the most extensive human barrier having a defense function against microbial and food antigens. This barrier is represented externally... (Review)
Review
The intestinal mucosa represents the most extensive human barrier having a defense function against microbial and food antigens. This barrier is represented externally by a mucus layer, consisting mainly of mucins, antimicrobial peptides, and secretory immunoglobulin A (sIgA), which serves as the first interaction with the intestinal microbiota. Below is placed the epithelial monolayer, comprising enterocytes and specialized cells, such as goblet cells, Paneth cells, enterochromaffin cells, and others, each with a specific protective, endocrine, or immune function. This layer interacts with both the luminal environment and the underlying lamina propria, where mucosal immunity processes primarily take place. Specifically, the interaction between the microbiota and an intact mucosal barrier results in the activation of tolerogenic processes, mainly mediated by FOXP3 regulatory T cells, underlying intestinal homeostasis. Conversely, the impairment of the mucosal barrier function, the alteration of the normal luminal microbiota composition (dysbiosis), or the imbalance between pro- and anti-inflammatory mucosal factors may result in inflammation and disease. Another crucial component of the intestinal barrier is the gut-vascular barrier, formed by endothelial cells, pericytes, and glial cells, which regulates the passage of molecules into the bloodstream. The aim of this review is to examine the various components of the intestinal barrier, assessing their interaction with the mucosal immune system, and focus on the immunological processes underlying homeostasis or inflammation.
Topics: Humans; Immunity, Mucosal; Endothelial Cells; Intestinal Mucosa; Inflammation; Homeostasis
PubMed: 37402104
DOI: 10.1007/s11739-023-03329-1 -
Oral Surgery, Oral Medicine, Oral... Nov 2013Oral keratinocytes and dendritic cells of the oral mucosa, through molecular pattern recognition receptors, distinguish between commensal and pathogenic microorganisms... (Review)
Review
Oral keratinocytes and dendritic cells of the oral mucosa, through molecular pattern recognition receptors, distinguish between commensal and pathogenic microorganisms and mediate the generation of protective immunoinflammatory responses to potentially invading pathogens or mediate immune tolerance toward commensal microorganisms. Oral immune tolerance is the result either of lack of activation of T cells in response to immunogenic presentation of antigens or of suppression of activity of effector T cells by regulatory T cells. Secretory immunoglobulin A (sIgA) antibodies at oral mucosal sites contribute to oral immunity by limiting colonization of microorganisms and their invasion of the epithelium. Ig isotype class switching to IgA is either dependent on or independent of T helper cells and is facilitated by cytokines secreted by dendritic cells and monocytes.
Topics: Cellular Microenvironment; Gingival Crevicular Fluid; Humans; Immune Tolerance; Immunity, Mucosal; Lymphoid Tissue; Mouth Mucosa; Saliva
PubMed: 24119522
DOI: 10.1016/j.oooo.2013.07.013 -
Science Immunology Jun 2022In this issue of , Barreto de Albuquerque track immune responsiveness to the foodborne pathogen during oral infection. Their findings extend the notion of... (Review)
Review
In this issue of , Barreto de Albuquerque track immune responsiveness to the foodborne pathogen during oral infection. Their findings extend the notion of compartmentalized immunity within the gastrointestinal tract to the oral cavity and provide previously unkown insights into regional specialization of oral immunity.
Topics: Gastrointestinal Tract; Humans; Immunity, Mucosal; Listeria monocytogenes; Listeriosis; Mouth Mucosa
PubMed: 35714199
DOI: 10.1126/sciimmunol.abp8632 -
Frontiers in Immunology 2023
Topics: Immunity, Mucosal; Immune System Diseases
PubMed: 37228613
DOI: 10.3389/fimmu.2023.1208798 -
Frontiers in Immunology 2023
Topics: Humans; Female; Immunity, Mucosal; Bacterial Proteins
PubMed: 37854596
DOI: 10.3389/fimmu.2023.1282709