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1.
Molecules ; 25(21)2020 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-33105830

RESUMO

Inflammation is a biological response to the activation of the immune system by various infectious or non-infectious agents, which may lead to tissue damage and various diseases. Gut commensal bacteria maintain a symbiotic relationship with the host and display a critical function in the homeostasis of the host immune system. Disturbance to the gut microbiota leads to immune dysfunction both locally and at distant sites, which causes inflammatory conditions not only in the intestine but also in the other organs such as lungs and brain, and may induce a disease state. Probiotics are well known to reinforce immunity and counteract inflammation by restoring symbiosis within the gut microbiota. As a result, probiotics protect against various diseases, including respiratory infections and neuroinflammatory disorders. A growing body of research supports the beneficial role of probiotics in lung and mental health through modulating the gut-lung and gut-brain axes. In the current paper, we discuss the potential role of probiotics in the treatment of viral respiratory infections, including the COVID-19 disease, as major public health crisis in 2020, and influenza virus infection, as well as treatment of neurological disorders like multiple sclerosis and other mental illnesses.


Assuntos
Infecções por Coronavirus/terapia , Influenza Humana/terapia , Transtornos Mentais/terapia , Esclerose Múltipla/terapia , Pneumonia Viral/terapia , Probióticos/uso terapêutico , Infecções Respiratórias/terapia , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/patogenicidade , Betacoronavirus/fisiologia , Encéfalo/imunologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/microbiologia , Infecções por Coronavirus/virologia , Microbioma Gastrointestinal/imunologia , Trato Gastrointestinal/imunologia , Trato Gastrointestinal/microbiologia , Humanos , Imunomodulação , Influenza Humana/imunologia , Influenza Humana/microbiologia , Influenza Humana/virologia , Pulmão/imunologia , Transtornos Mentais/imunologia , Transtornos Mentais/microbiologia , Consórcios Microbianos/imunologia , Esclerose Múltipla/imunologia , Esclerose Múltipla/microbiologia , Orthomyxoviridae/efeitos dos fármacos , Orthomyxoviridae/patogenicidade , Orthomyxoviridae/fisiologia , Pandemias , Pneumonia Viral/imunologia , Pneumonia Viral/microbiologia , Pneumonia Viral/virologia , Infecções Respiratórias/imunologia , Infecções Respiratórias/microbiologia , Simbiose/imunologia
2.
Front Immunol ; 11: 2192, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33072084

RESUMO

During the last years probiotics gained the attention of clinicians for their use in the prevention and treatment of multiple diseases. Probiotics main mechanisms of action include enhanced mucosal barrier function, direct antagonism with pathogens, inhibition of bacterial adherence and invasion capacity in the intestinal epithelium, boosting of the immune system and regulation of the central nervous system. It is accepted that there is a mutual communication between the gut microbiota and the liver, the so-called "microbiota-gut-liver axis" as well as a reciprocal communication between the intestinal microbiota and the central nervous system through the "microbiota-gut-brain axis." Moreover, recently the "gut-lung axis" in bacterial and viral infections is considerably discussed for bacterial and viral infections, as the intestinal microbiota amplifies the alveolar macrophage activity having a protective role in the host defense against pneumonia. The importance of the normal human intestinal microbiota is recognized in the preservation of health. Disease states such as, infections, autoimmune conditions, allergy and other may occur when the intestinal balance is disturbed. Probiotics seem to be a promising approach to prevent and even reduce the symptoms of such clinical states as an adjuvant therapy by preserving the balance of the normal intestinal microbiota and improving the immune system. The present review states globally all different disorders in which probiotics can be given. To date, Stronger data in favor of their clinical use are provided in the prevention of gastrointestinal disorders, antibiotic-associated diarrhea, allergy and respiratory infections. We hereby discuss the role of probiotics in the reduction of the respiratory infection symptoms and we focus on the possibility to use them as an adjuvant to the therapeutic approach of the pandemic COVID-19. Nevertheless, it is accepted by the scientific community that more clinical studies should be undertaken in large samples of diseased populations so that the assessment of their therapeutic potential provide us with strong evidence for their efficacy and safety in clinical use.


Assuntos
Bactérias/imunologia , Betacoronavirus/imunologia , Infecções por Coronavirus , Microbioma Gastrointestinal/imunologia , Pandemias , Pneumonia Viral , Probióticos/uso terapêutico , Aderência Bacteriana/imunologia , Encéfalo/imunologia , Encéfalo/microbiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/microbiologia , Infecções por Coronavirus/terapia , Humanos , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Pneumonia Viral/epidemiologia , Pneumonia Viral/imunologia , Pneumonia Viral/microbiologia , Pneumonia Viral/terapia
3.
Proc Natl Acad Sci U S A ; 117(38): 23674-23683, 2020 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-32907933

RESUMO

The gut microbiome has garnered attention as an effective target to boost immunity and improve cancer immunotherapy. We found that B cell-defective (BCD) mice, such as µ-membrane targeted deletion (µMT) and activation-induced cytidine deaminase (AID) knockouts (KOs), have elevated antitumor immunity under specific pathogen-free but not germ-free conditions. Microbial dysbiosis in these BCD mice enriched the type I IFN (IFN) signature in mucosal CD8+ T cells, resulting in up-regulation of the type I IFN-inducible protein stem cell antigen-1 (Sca-1). Among CD8+ T cells, naïve cells predominantly circulate from the gut to the periphery, and those that had migrated from the mesenteric lymph nodes (mLNs) to the periphery had significantly higher expression of Sca-1. The gut-educated Sca-1+ naïve subset is endowed with enhanced mitochondrial activity and antitumor effector potential. The heterogeneity and functional versatility of the systemic naïve CD8+ T cell compartment was revealed by single-cell analysis and functional assays of CD8+ T cell subpopulations. These results indicate one of the potential mechanisms through which microbial dysbiosis regulates antitumor immunity.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Microbioma Gastrointestinal/imunologia , Interferon Tipo I/imunologia , Neoplasias Experimentais/imunologia , Animais , Antígenos Ly/imunologia , Antígenos Ly/metabolismo , Linfócitos B , Linhagem Celular Tumoral , Células Cultivadas , Disbiose/imunologia , Imunoglobulina A/imunologia , Imunoglobulina A/metabolismo , Interferon Tipo I/metabolismo , Linfonodos/citologia , Proteínas de Membrana/imunologia , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais/imunologia
4.
Nature ; 585(7826): 509-517, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32968260

RESUMO

Colorectal cancer (CRC) is a heterogeneous disease of the intestinal epithelium that is characterized by the accumulation of mutations and a dysregulated immune response. Up to 90% of disease risk is thought to be due to environmental factors such as diet, which is consistent with a growing body of literature that describes an 'oncogenic' CRC-associated microbiota. Whether this dysbiosis contributes to disease or merely represents a bystander effect remains unclear. To prove causation, it will be necessary to decipher which specific taxa or metabolites drive CRC biology and to fully characterize the underlying mechanisms. Here we discuss the host-microbiota interactions in CRC that have been reported so far, with particular focus on mechanisms that are linked to intestinal barrier disruption, genotoxicity and deleterious inflammation. We further comment on unknowns and on the outstanding challenges in the field, and how cutting-edge technological advances might help to overcome these. More detailed mechanistic insights into the complex CRC-associated microbiota would potentially reveal avenues that can be exploited for clinical benefit.


Assuntos
Neoplasias Colorretais/microbiologia , Neoplasias Colorretais/fisiopatologia , Microbioma Gastrointestinal , Animais , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/terapia , Disbiose/metabolismo , Disbiose/microbiologia , Microbioma Gastrointestinal/imunologia , Humanos , Inflamação/microbiologia , Mutagênese
5.
PLoS Biol ; 18(9): e3000813, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32991574

RESUMO

Short-chain fatty acids (SCFAs) produced by gastrointestinal microbiota regulate immune responses, but host molecular mechanisms remain unknown. Unbiased screening using SCFA-conjugated affinity nanobeads identified apoptosis-associated speck-like protein (ASC), an adaptor protein of inflammasome complex, as a noncanonical SCFA receptor besides GPRs. SCFAs promoted inflammasome activation in macrophages by binding to its ASC PYRIN domain. Activated inflammasome suppressed survival of Salmonella enterica serovar Typhimurium (S. Typhimurium) in macrophages by pyroptosis and facilitated neutrophil recruitment to promote bacterial elimination and thus inhibit systemic dissemination in the host. Administration of SCFAs or dietary fibers, which are fermented to SCFAs by gut bacteria, significantly prolonged the survival of S. Typhimurium-infected mice through ASC-mediated inflammasome activation. SCFAs penetrated into the inflammatory region of the infected gut mucosa to protect against infection. This study provided evidence that SCFAs suppress Salmonella infection via inflammasome activation, shedding new light on the therapeutic activity of dietary fiber.


Assuntos
Proteínas Adaptadoras de Sinalização CARD/metabolismo , Ácidos Graxos Voláteis/metabolismo , Inflamassomos/imunologia , Inflamassomos/metabolismo , Receptores Acoplados a Proteínas-G/metabolismo , Infecções por Salmonella/prevenção & controle , Animais , Proteínas Adaptadoras de Sinalização CARD/genética , Feminino , Microbioma Gastrointestinal/imunologia , Células HEK293 , Humanos , Imunidade Inata/fisiologia , Ativação de Macrófagos/genética , Ativação de Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ligação Proteica , Receptores Acoplados a Proteínas-G/genética , Infecções por Salmonella/genética , Infecções por Salmonella/imunologia , Infecções por Salmonella/metabolismo , Salmonella typhimurium/imunologia , Células U937
6.
Nat Commun ; 11(1): 4457, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901017

RESUMO

Innate lymphoid cells (ILCs) and CD4+ T cells produce IL-22, which is critical for intestinal immunity. The microbiota is central to IL-22 production in the intestines; however, the factors that regulate IL-22 production by CD4+ T cells and ILCs are not clear. Here, we show that microbiota-derived short-chain fatty acids (SCFAs) promote IL-22 production by CD4+ T cells and ILCs through G-protein receptor 41 (GPR41) and inhibiting histone deacetylase (HDAC). SCFAs upregulate IL-22 production by promoting aryl hydrocarbon receptor (AhR) and hypoxia-inducible factor 1α (HIF1α) expression, which are differentially regulated by mTOR and Stat3. HIF1α binds directly to the Il22 promoter, and SCFAs increase HIF1α binding to the Il22 promoter through histone modification. SCFA supplementation enhances IL-22 production, which protects intestines from inflammation. SCFAs promote human CD4+ T cell IL-22 production. These findings establish the roles of SCFAs in inducing IL-22 production in CD4+ T cells and ILCs to maintain intestinal homeostasis.


Assuntos
Ácidos Graxos Voláteis/imunologia , Microbioma Gastrointestinal/imunologia , Imunidade Inata , Interleucinas/biossíntese , Animais , Butiratos/imunologia , Butiratos/metabolismo , Butiratos/farmacologia , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/microbiologia , Citrobacter rodentium , Colite/imunologia , Colite/microbiologia , Colite/prevenção & controle , Infecções por Enterobacteriaceae/imunologia , Infecções por Enterobacteriaceae/microbiologia , Infecções por Enterobacteriaceae/prevenção & controle , Ácidos Graxos Voláteis/metabolismo , Ácidos Graxos Voláteis/farmacologia , Microbioma Gastrointestinal/fisiologia , Inibidores de Histona Desacetilases/farmacologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Técnicas In Vitro , Interleucinas/deficiência , Interleucinas/genética , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Linfócitos/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Regiões Promotoras Genéticas , Receptores de Hidrocarboneto Arílico/metabolismo , Receptores Acoplados a Proteínas-G/metabolismo
7.
Nat Commun ; 11(1): 4475, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901029

RESUMO

Tissue resident memory CD8+ T cells (Trm) are poised for immediate reactivation at sites of pathogen entry and provide optimal protection of mucosal surfaces. The intestinal tract represents a portal of entry for many infectious agents; however, to date specific strategies to enhance Trm responses at this site are lacking. Here, we present TMDI (Transient Microbiota Depletion-boosted Immunization), an approach that leverages antibiotic treatment to temporarily restrain microbiota-mediated colonization resistance, and favor intestinal expansion to high densities of an orally-delivered Listeria monocytogenes strain carrying an antigen of choice. By augmenting the local chemotactic gradient as well as the antigenic load, this procedure generates a highly expanded pool of functional, antigen-specific intestinal Trm, ultimately enhancing protection against infectious re-challenge in mice. We propose that TMDI is a useful model to dissect the requirements for optimal Trm responses in the intestine, and also a potential platform to devise novel mucosal vaccination approaches.


Assuntos
Microbioma Gastrointestinal/imunologia , Imunidade nas Mucosas , Administração Oral , Animais , Antígenos/administração & dosagem , Linfócitos T CD8-Positivos/imunologia , Quimiotaxia/imunologia , Feminino , Microbioma Gastrointestinal/efeitos dos fármacos , Interações entre Hospedeiro e Microrganismos/imunologia , Imunidade nas Mucosas/efeitos dos fármacos , Memória Imunológica , Listeria monocytogenes/crescimento & desenvolvimento , Listeria monocytogenes/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ovalbumina/administração & dosagem , Estreptomicina/administração & dosagem
8.
Proc Natl Acad Sci U S A ; 117(35): 21536-21545, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32817490

RESUMO

The building evidence for the contribution of microbiota to human disease has spurred an effort to develop therapies that target the gut microbiota. This is particularly evident in inflammatory bowel diseases (IBDs), where clinical trials of fecal microbiota transplantation have shown some efficacy. To aid the development of novel microbiota-targeted therapies and to better understand the biology underpinning such treatments, we have used gnotobiotic mice to model microbiota manipulations in the context of microbiotas from humans with inflammatory bowel disease. Mice colonized with IBD donor-derived microbiotas exhibit a stereotypical set of phenotypes, characterized by abundant mucosal Th17 cells, a deficit in the tolerogenic RORγt+ regulatory T (Treg) cell subset, and susceptibility to disease in colitis models. Transplanting healthy donor-derived microbiotas into mice colonized with human IBD microbiotas led to induction of RORγt+ Treg cells, which was associated with an increase in the density of the microbiotas following transplant. Microbiota transplant reduced gut Th17 cells in mice colonized with a microbiota from a donor with Crohn's disease. By culturing strains from this microbiota and screening them in vivo, we identified a specific strain that potently induces Th17 cells. Microbiota transplants reduced the relative abundance of this strain in the gut microbiota, which was correlated with a reduction in Th17 cells and protection from colitis.


Assuntos
Transplante de Microbiota Fecal , Doenças Inflamatórias Intestinais/microbiologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Animais , Colite/prevenção & controle , Colo/microbiologia , Doença de Crohn/metabolismo , Doença de Crohn/microbiologia , Citocinas/imunologia , Modelos Animais de Doenças , Fezes/microbiologia , Feminino , Microbioma Gastrointestinal/imunologia , Humanos , Doenças Inflamatórias Intestinais/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T Reguladores/microbiologia , Células Th17/microbiologia
9.
Nat Commun ; 11(1): 4142, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32811831

RESUMO

Glycans are involved in various life processes and represent critical targets of biomedical developments. Nevertheless, the accessibility to long glycans with precise structures remains challenging. Here we report on the synthesis of glycans consisting of [→4)-α-Rha-(1 → 3)-ß-Man-(1 → ] repeating unit, which are relevant to the O-antigen of Bacteroides vulgatus, a common component of gut microbiota. The optimal combination of assembly strategy, protecting group arrangement, and glycosylation reaction has enabled us to synthesize up to a 128-mer glycan. The synthetic glycans are accurately characterized by advanced NMR and MS approaches, the 3D structures are defined, and their potent binding activity with human DC-SIGN, a receptor associated with the gut lymphoid tissue, is disclosed.


Assuntos
Bacteroides/química , Antígenos O/química , Polissacarídeos/síntese química , Bacteroides/imunologia , Bacteroides/metabolismo , Microbioma Gastrointestinal/imunologia , Humanos , Lipopolissacarídeos/química , Lipopolissacarídeos/imunologia , Espectroscopia de Ressonância Magnética , Antígenos O/imunologia , Antígenos O/metabolismo , Polissacarídeos/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
10.
J Vis Exp ; (161)2020 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-32773765

RESUMO

Gut microbiota exert pleiotropic roles in human health and disease. Fecal microbiota transplantation (FMT) is an effective method to investigate the biological function of intestinal bacteria as a whole or at the species level. Several different FMT methods have been published. Here, we present an FMT protocol that successfully depletes gut microbiota in a matter of days, followed by transplantation of fecal microbiota from fresh or frozen donor intestinal contents to conventional mice. Real time-PCR is applied to test the efficacy of bacterial depletion. Sequencing of the 16S ribosomal RNA (rRNA) is then applied to test the relative abundance and identity of gut microbiota in recipient mice. We also present a flow cytometry-based detection method of immunoglobulin A (IgA)-coated bacteria in the gut.


Assuntos
Transplante de Microbiota Fecal/métodos , Microbioma Gastrointestinal/imunologia , Imunoglobulina A/metabolismo , Animais , Humanos , Camundongos , Prevalência
11.
PLoS One ; 15(8): e0237086, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764782

RESUMO

Paramylon is a novel ß-glucan that is stored by Euglena gracilis Z, which is a unicellular photosynthesizing green alga with characteristics of both animals and plants. Recent studies have indicated that paramylon functions as an immunomodulator or a dietary fiber. Currently, chronic kidney disease (CKD) is a global health problem, and there is no effective preventive treatment for CKD progression. However, paramylon may suppress the progression of CKD via the elimination of uremic toxins or modulation of gut microbiota, leading to the alleviation of inflammation. The aim of this study was to evaluate the effect of paramylon in CKD rat model. Eight-week-old male Wistar rats with a 5/6 nephrectomy were given either a normal diet or a diet containing 5% paramylon for 8 weeks. Proteinuria was measured intermittently. Serum and kidney tissues were harvested after sacrifice. We performed a renal molecular and histopathological investigation, serum metabolome analysis, and gut microbiome analysis. The results showed that paramylon attenuated renal function, glomerulosclerosis, tubulointerstitial injury, and podocyte injury in the CKD rat model. Renal fibrosis, tubulointerstitial inflammatory cell infiltration, and proinflammatory cytokine gene expression levels tended to be suppressed with paramylon treatment. Further, paramylon inhibited the accumulation of uremic toxins, including tricarboxylic acid (TCA) cycle-related metabolites and modulated a part of CKD-related gut microbiota in the CKD rat model. In conclusion, we suggest that paramylon mainly inhibited the absorption of non-microbiota-derived uremic solutes, leading to protect renal injury via anti-inflammatory and anti-fibrotic effects. Paramylon may be a novel compound that can act against CKD progression.


Assuntos
Glucanos/farmacologia , Rim/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Proteinúria/tratamento farmacológico , Insuficiência Renal Crônica/tratamento farmacológico , Administração Oral , Animais , Ciclo do Ácido Cítrico/efeitos dos fármacos , Citocinas/metabolismo , Modelos Animais de Doenças , Euglena gracilis/química , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/imunologia , Glucanos/isolamento & purificação , Glucanos/uso terapêutico , Humanos , Mediadores da Inflamação/metabolismo , Absorção Intestinal/efeitos dos fármacos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia , Rim/imunologia , Rim/patologia , Masculino , Substâncias Protetoras/isolamento & purificação , Substâncias Protetoras/uso terapêutico , Proteinúria/sangue , Proteinúria/patologia , Ratos , Ratos Wistar , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/patologia , Insuficiência Renal Crônica/urina , Toxinas Biológicas/sangue , Toxinas Biológicas/metabolismo
12.
PLoS One ; 15(8): e0237118, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32764795

RESUMO

The objective of this study was to evaluate the effect of supplementation with 100ppm sodium monensin or 0.15% of a blend of functional oils (cashew nut oil + castor oil) on the intestinal microbiota of broilers challenged with three different Eimeria spp. The challenge was accomplished by inoculating broiler chicks with sporulated oocysts of Eimeria tenella, Eimeria acervulina, and Eimeria maxima via oral gavage. A total of 864, day-old male broiler chicks (Cobb) were randomly assigned to six treatments (eight pens/treatment; 18 broilers/pen) in a 3 × 2 factorial arrangement, composed of three additives (control, monensin or blend), with or without Eimeria challenge. Intestinal contents was collected at 28 days of age for microbiota analysis by sequencing 16s rRNA in V3 and V4 regions using the Illumina MiSeq platform. Taxonomy was assigned through the SILVA database version 132, using the QIIME 2 software version 2019.1. No treatment effects (p > 0.05) were observed in the microbial richness at the family level estimated by Chao1 and the biodiversity assessed by Simpson's index, except for Shannon's index (p < 0.05). The intestinal microbiota was dominated by members of the order Clostridiales and Lactobacillales, followed by the families Ruminococcaceae, Bacteroidaceae, and Lactobacillaceae, regardless of treatment. When the controls were compared, in the challenged control group there was an increase in Erysipelotrichaceae, Lactobacillaceae, Bacteroidaceae, Streptococcaceae, and Peptostreptococcaceae, and a decrease in Ruminococcaceae. Similar results were found for a challenged group that received monensin, while the blend partially mitigated this variation. Therefore, the blend alleviated the impact of coccidiosis challenge on the microbiome of broilers compared to monensin.


Assuntos
Coccidiose/veterinária , Eimeria/isolamento & purificação , Microbioma Gastrointestinal/efeitos dos fármacos , Monensin/administração & dosagem , Óleos Vegetais/administração & dosagem , Doenças das Aves Domésticas/dietoterapia , Anacardium/química , Ração Animal , Animais , Galinhas/parasitologia , Coccidiose/dietoterapia , Coccidiose/imunologia , Coccidiose/parasitologia , DNA de Protozoário/isolamento & purificação , Eimeria/genética , Eimeria/imunologia , Eimeria/patogenicidade , Microbioma Gastrointestinal/imunologia , Masculino , Oocistos/patogenicidade , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/parasitologia , RNA Ribossômico 16S/genética , Ricinus/química
13.
Nature ; 585(7823): 102-106, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32848245

RESUMO

Accumulating evidence indicates that gut microorganisms have a pathogenic role in autoimmune diseases, including in multiple sclerosis1. Studies of experimental autoimmune encephalomyelitis (an animal model of multiple sclerosis)2,3, as well as human studies4-6, have implicated gut microorganisms in the development or severity of multiple sclerosis. However, it remains unclear how gut microorganisms act on the inflammation of extra-intestinal tissues such as the spinal cord. Here we show that two distinct signals from gut microorganisms coordinately activate autoreactive T cells in the small intestine that respond specifically to myelin oligodendrocyte glycoprotein (MOG). After induction of experimental autoimmune encephalomyelitis in mice, MOG-specific CD4+ T cells are observed in the small intestine. Experiments using germ-free mice that were monocolonized with microorganisms from the small intestine demonstrated that a newly isolated strain in the family Erysipelotrichaceae acts similarly to an adjuvant to enhance the responses of T helper 17 cells. Shotgun sequencing of the contents of the small intestine revealed a strain of Lactobacillus reuteri that possesses peptides that potentially mimic MOG. Mice that were co-colonized with these two strains showed experimental autoimmune encephalomyelitis symptoms that were more severe than those of germ-free or monocolonized mice. These data suggest that the synergistic effects that result from the presence of these microorganisms should be considered in the pathogenicity of multiple sclerosis, and that further study of these microorganisms may lead to preventive strategies for this disease.


Assuntos
Encefalomielite Autoimune Experimental/microbiologia , Microbioma Gastrointestinal/imunologia , Inflamação/patologia , Medula Espinal/patologia , Linfócitos T/imunologia , Linfócitos T/patologia , Animais , Modelos Animais de Doenças , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/patologia , Encefalomielite Autoimune Experimental/prevenção & controle , Feminino , Vida Livre de Germes , Inflamação/imunologia , Intestino Delgado/imunologia , Intestino Delgado/microbiologia , Intestino Delgado/patologia , Lactobacillus reuteri/química , Lactobacillus reuteri/imunologia , Lactobacillus reuteri/patogenicidade , Masculino , Camundongos , Esclerose Múltipla/imunologia , Esclerose Múltipla/microbiologia , Esclerose Múltipla/patologia , Glicoproteína Mielina-Oligodendrócito/química , Glicoproteína Mielina-Oligodendrócito/imunologia , Medula Espinal/imunologia , Células Th17/imunologia , Células Th17/patologia
14.
Science ; 369(6506): 936-942, 2020 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-32820119

RESUMO

Intestinal microbiota have been proposed to induce commensal-specific memory T cells that cross-react with tumor-associated antigens. We identified major histocompatibility complex (MHC) class I-binding epitopes in the tail length tape measure protein (TMP) of a prophage found in the genome of the bacteriophage Enterococcus hirae Mice bearing E. hirae harboring this prophage mounted a TMP-specific H-2Kb-restricted CD8+ T lymphocyte response upon immunotherapy with cyclophosphamide or anti-PD-1 antibodies. Administration of bacterial strains engineered to express the TMP epitope improved immunotherapy in mice. In renal and lung cancer patients, the presence of the enterococcal prophage in stools and expression of a TMP-cross-reactive antigen by tumors correlated with long-term benefit of PD-1 blockade therapy. In melanoma patients, T cell clones recognizing naturally processed cancer antigens that are cross-reactive with microbial peptides were detected.


Assuntos
Antígenos de Neoplasias/imunologia , Bacteriófagos/imunologia , Streptococcus faecium ATCC 9790/virologia , Microbioma Gastrointestinal/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Imunoterapia/métodos , Neoplasias/terapia , Proteínas da Cauda Viral/imunologia , Animais , Anticorpos Monoclonais/uso terapêutico , Antineoplásicos Alquilantes/uso terapêutico , Linfócitos T CD8-Positivos/imunologia , Reações Cruzadas , Ciclofosfamida/uso terapêutico , Epitopos/imunologia , Fezes/virologia , Antígenos H-2/imunologia , Humanos , Camundongos , Neoplasias/dietoterapia , Neoplasias/imunologia , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/imunologia , Proteínas da Cauda Viral/uso terapêutico
15.
PLoS Pathog ; 16(8): e1008766, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32857822

RESUMO

Pathogens commonly disrupt the intestinal epithelial barrier; however, how the epithelial immune system senses the loss of intestinal barrier as a danger signal to activate self-defense is unclear. Through an unbiased approach in the model nematode Caenorhabditis elegans, we found that the EGL-44/TEAD transcription factor and its transcriptional activator YAP-1/YAP (Yes-associated protein) were activated when the intestinal barrier was disrupted by infections with the pathogenic bacterium Pseudomonas aeruginosa PA14. Gene Ontology enrichment analysis of the genes containing the TEAD-binding sites revealed that "innate immune response" and "defense response to Gram-negative bacterium" were two top significantly overrepresented terms. Genetic inactivation of yap-1 and egl-44 significantly reduced the survival rate and promoted bacterial accumulation in worms after bacterial infections. Furthermore, we found that disturbance of the E-cadherin-based adherens junction triggered the nuclear translocation and activation of YAP-1/YAP in the gut of worms. Although YAP is a major downstream effector of the Hippo signaling, our study revealed that the activation of YAP-1/YAP was independent of the Hippo pathway during disruption of intestinal barrier. After screening 10 serine/threonine phosphatases, we identified that PP2A phosphatase was involved in the activation of YAP-1/YAP after intestinal barrier loss induced by bacterial infections. Additionally, our study demonstrated that the function of YAP was evolutionarily conserved in mice. Our study highlights how the intestinal epithelium recognizes the loss of the epithelial barrier as a danger signal to deploy defenses against pathogens, uncovering an immune surveillance program in the intestinal epithelium.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Permeabilidade da Membrana Celular , Células Epiteliais/imunologia , Microbioma Gastrointestinal/imunologia , Salmonelose Animal/imunologia , Salmonella typhimurium/imunologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Caenorhabditis elegans , Proteínas de Caenorhabditis elegans/genética , Células Epiteliais/metabolismo , Células Epiteliais/microbiologia , Células Epiteliais/patologia , Camundongos , Salmonelose Animal/metabolismo , Salmonelose Animal/microbiologia , Salmonelose Animal/patologia , Transdução de Sinais
16.
J Immunother Cancer ; 8(2)2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32675312

RESUMO

BACKGROUND: Pandemic COVID-19 by severe acute respiratory syndrome (SARS) coronavirus 2 (SARS-CoV-2) infection is facilitated by the ACE2 receptor and protease TMPRSS2. Modestly sized case series have described clinical factors associated with COVID-19, while ACE2 and TMPRSS2 expression analyses have been described in some cell types. Patients with cancer may have worse outcomes to COVID-19. METHODS: We performed an integrated study of ACE2 and TMPRSS2 gene expression across and within organ systems, by normal versus tumor, across several existing databases (The Cancer Genome Atlas, Census of Immune Single Cell Expression Atlas, The Human Cell Landscape, and more). We correlated gene expression with clinical factors (including but not limited to age, gender, race, body mass index, and smoking history), HLA genotype, immune gene expression patterns, cell subsets, and single-cell sequencing as well as commensal microbiome. RESULTS: Matched normal tissues generally display higher ACE2 and TMPRSS2 expression compared with cancer, with normal and tumor from digestive organs expressing the highest levels. No clinical factors were consistently identified to be significantly associated with gene expression levels though outlier organ systems were observed for some factors. Similarly, no HLA genotypes were consistently associated with gene expression levels. Strong correlations were observed between ACE2 expression levels and multiple immune gene signatures including interferon-stimulated genes and the T cell-inflamed phenotype as well as inverse associations with angiogenesis and transforming growth factor-ß signatures. ACE2 positively correlated with macrophage subsets across tumor types. TMPRSS2 was less associated with immune gene expression but was strongly associated with epithelial cell abundance. Single-cell sequencing analysis across nine independent studies demonstrated little to no ACE2 or TMPRSS2 expression in lymphocytes or macrophages. ACE2 and TMPRSS2 gene expression associated with commensal microbiota in matched normal tissues particularly from colorectal cancers, with distinct bacterial populations showing strong associations. CONCLUSIONS: We performed a large-scale integration of ACE2 and TMPRSS2 gene expression across clinical, genetic, and microbiome domains. We identify novel associations with the microbiota and confirm host immunity associations with gene expression. We suggest caution in interpretation regarding genetic associations with ACE2 expression suggested from smaller case series.


Assuntos
Betacoronavirus/imunologia , Infecções por Coronavirus/imunologia , Neoplasias/imunologia , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/imunologia , Serina Endopeptidases/metabolismo , Idoso , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Conjuntos de Dados como Assunto , Feminino , Microbioma Gastrointestinal/imunologia , Regulação Neoplásica da Expressão Gênica/imunologia , Antígenos HLA/sangue , Antígenos HLA/imunologia , Humanos , Macrófagos/imunologia , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/microbiologia , Neoplasias/patologia , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , RNA-Seq
18.
Nat Med ; 26(7): 1089-1095, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32632193

RESUMO

Modern lifestyles increase the risk of chronic diseases, in part by modifying the microbiome, but the health effects of lifestyles enforced on ethnic minorities are understudied1-3. Lifestyle affects the microbiome early in life, when the microbiome is assembled and the immune system is undergoing maturation4-6. Moreover, the influence of lifestyle has been separated from genetic and geographic factors by studies of genetically similar populations and ethnically distinct groups living in the same geographic location7-11. The lifestyle of Irish Travellers, an ethnically distinct subpopulation, changed with legislation in 2002 that effectively ended nomadism and altered their living conditions. Comparative metagenomics of gut microbiomes shows that Irish Travellers retain a microbiota similar to that of non-industrialized societies. Their microbiota is associated with non-dietary factors and is proportionately linked with risk of microbiome-related metabolic disease. Our findings suggest there are microbiome-related public health implications when ethnic minorities are pressured to change lifestyles.


Assuntos
Doença Crônica/epidemiologia , Microbioma Gastrointestinal/genética , Sistema Imunitário/imunologia , Estilo de Vida , Adulto , Grupos Étnicos/genética , Fezes/microbiologia , Microbioma Gastrointestinal/imunologia , Genética Populacional , Humanos , Sistema Imunitário/microbiologia , Irlanda/epidemiologia , Masculino , Metagenômica/métodos , Microbiota/genética , Microbiota/imunologia , Filogenia , Roma/genética , Migrantes
19.
Virus Res ; 286: 198103, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32717345

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has evolved into a major pandemic called coronavirus disease 2019 (COVID-19) that has created unprecedented global health emergencies, and emerged as a serious threat due to its strong ability for human-to-human transmission. The reports indicate the ability of SARS-CoV-2 to affect almost any organ due to the presence of a receptor known as angiotensin converting enzyme 2 (ACE2) across the body. ACE2 receptor is majorly expressed in the brush border of gut enterocytes along with the ciliated cells and alveolar epithelial type II cells in the lungs. The amino acid transport function of ACE2 has been linked to gut microbial ecology in gastrointestinal (GI) tract, thereby suggesting that COVID-19 may, to some level, be linked to the enteric microbiota. The significant number of COVID-19 patients shows extra-pulmonary symptoms in the GI tract. Many subsequent studies revealed viral RNA of SARS-CoV-2 in fecal samples of COVID-19 patients. This presents a new challenge in the diagnosis and control of COVID-19 infection with a caution for proper sanitation and hygiene. Here, we aim to discuss the immunological co-ordination between gut and lungs that facilitates SARS-CoV-2 to infect and multiply in the inflammatory bowel disease (IBD) and non-IBD patients.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/imunologia , Síndrome da Liberação de Citocina/imunologia , Disbiose/imunologia , Trato Gastrointestinal/imunologia , Doenças Inflamatórias Intestinais/imunologia , Pulmão/imunologia , Pneumonia Viral/imunologia , Anticorpos Monoclonais/uso terapêutico , Antivirais/uso terapêutico , Betacoronavirus/imunologia , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/microbiologia , Infecções por Coronavirus/virologia , Síndrome da Liberação de Citocina/tratamento farmacológico , Síndrome da Liberação de Citocina/microbiologia , Síndrome da Liberação de Citocina/virologia , Citocinas/antagonistas & inibidores , Citocinas/genética , Citocinas/imunologia , Disbiose/tratamento farmacológico , Disbiose/microbiologia , Disbiose/virologia , Microbioma Gastrointestinal/imunologia , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/microbiologia , Trato Gastrointestinal/virologia , Expressão Gênica , Interações Hospedeiro-Patógeno/imunologia , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/microbiologia , Doenças Inflamatórias Intestinais/virologia , Pulmão/efeitos dos fármacos , Pulmão/microbiologia , Pulmão/virologia , Pandemias , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/imunologia , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/microbiologia , Pneumonia Viral/virologia , Receptores Virais/genética , Receptores Virais/imunologia
20.
Nature ; 582(7812): 421-425, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32499646

RESUMO

The antigen-binding variable regions of the B cell receptor (BCR) and of antibodies are encoded by exons that are assembled in developing B cells by V(D)J recombination1. The BCR repertoires of primary B cells are vast owing to mechanisms that create diversity at the junctions of V(D)J gene segments that contribute to complementarity-determining region 3 (CDR3), the region that binds antigen1. Primary B cells undergo antigen-driven BCR affinity maturation through somatic hypermutation and cellular selection in germinal centres (GCs)2,3. Although most GCs are transient3, those in intestinal Peyer's patches (PPs)-which depend on the gut microbiota-are chronic4, and little is known about their BCR repertoires or patterns of somatic hypermutation. Here, using a high-throughput assay that analyses both V(D)J segment usage and somatic hypermutation profiles, we elucidate physiological BCR repertoires in mouse PP GCs. PP GCs from different mice expand public BCR clonotypes (clonotypes that are shared between many mice) that often have canonical CDR3s in the immunoglobulin heavy chain that, owing to junctional biases during V(D)J recombination, appear much more frequently than predicted in naive B cell repertoires. Some public clonotypes are dependent on the gut microbiota and encode antibodies that are reactive to bacterial glycans, whereas others are independent of gut bacteria. Transfer of faeces from specific-pathogen-free mice to germ-free mice restored germ-dependent clonotypes, directly implicating BCR selection. We identified somatic hypermutations that were recurrently selected in such public clonotypes, indicating that affinity maturation occurs in mouse PP GCs under homeostatic conditions. Thus, persistent gut antigens select recurrent BCR clonotypes to seed chronic PP GC responses.


Assuntos
Afinidade de Anticorpos/genética , Centro Germinativo/citologia , Centro Germinativo/imunologia , Nódulos Linfáticos Agregados/citologia , Nódulos Linfáticos Agregados/imunologia , Receptores de Antígenos de Linfócitos B/imunologia , Receptores de Antígenos de Linfócitos B/metabolismo , Animais , Fezes/microbiologia , Microbioma Gastrointestinal/imunologia , Genes de Cadeia Pesada de Imunoglobulina/genética , Vida Livre de Germes , Homeostase , Humanos , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/imunologia , Camundongos , Seleção Genética , Hipermutação Somática de Imunoglobulina/genética , Recombinação V(D)J/genética
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