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1.
Anticancer Res ; 40(10): 5457-5462, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32988867

RESUMO

BACKGROUND/AIM: Several studies have found elevated soluble CD40 Ligand (sCD40L) in the serum of patients with malignancies as well as those with inflammatory bowel disease (IBD). Our goal was to determine the possible causal role of sCD40L in colitis-associated colorectal cancer (CAC) by using the well-established azoxymethane/dextran sulfate sodium (AOM/DSS) protocol. MATERIALS AND METHODS: Twelve wild type (WT) and twelve TLR4 knock out (KO) female C57BL6 mice were divided into 4 experimental groups. Six WT and six TLR4 KO mice were treated with a single intraperitoneal dose (10 mg/kg of body weight) of AOM followed by three 7-day cycles of oral 2.5% DSS. The other two groups included 6 WT and 6 TLR4 KO mice that received only water and served as the control groups. The mice were sacrificed after 84 days. RESULTS: All mice in the AOM/DSS WT group developed CAC while all mice from the AOM/DSS TLR4 KO group were protected from CAC. We measured the serum and pathologic tissue levels of sCD40L with quantitative sandwich enzyme-linked immunoassay (ELISA) and found that serum sCD40L was significantly higher in wild-type mice that developed CAC compared to their healthy counterparts (wild-type and TLR-4 KO controls). In comparison, serum sCD40L levels were comparable between TLR-4 KO mice, which are protected from developing CAC, and their healthy counterparts (wild-type and TLR-4 KO controls). Of note, tissue levels of sCD40L were not affected by the development of CAC. CONCLUSION: Our findings point to the presence of an axis between TLR-4 and sCD40L, which may lead to decreased immunosurveillance and the subsequent development of colitis-associated cancer.


Assuntos
Ligante de CD40/genética , Colite/imunologia , Neoplasias Colorretais/induzido quimicamente , Receptor 4 Toll-Like/genética , Animais , Azoximetano/toxicidade , Colite/induzido quimicamente , Colite/genética , Colite/patologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Humanos , Imunidade Inata/genética , Camundongos , Camundongos Knockout
2.
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
3.
PLoS Pathog ; 16(8): e1008763, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32834002

RESUMO

The various sub-species of Salmonella enterica cause a range of disease in human hosts. The human-adapted Salmonella enterica serovar Typhi enters the gastrointestinal tract and invades systemic sites to cause enteric (typhoid) fever. In contrast, most non-typhoidal serovars of Salmonella are primarily restricted to gut tissues. Across Africa, invasive non-typhoidal Salmonella (iNTS) have emerged with an ability to spread beyond the gastrointestinal tract and cause systemic bloodstream infections with increased morbidity and mortality. To investigate this evolution in pathogenesis, we compared the genomes of African iNTS isolates with other Salmonella enterica serovar Typhimurium and identified several macA and macB gene variants unique to African iNTS. MacAB forms a tripartite efflux pump with TolC and is implicated in Salmonella pathogenesis. We show that macAB transcription is upregulated during macrophage infection and after antimicrobial peptide exposure, with macAB transcription being supported by the PhoP/Q two-component system. Constitutive expression of macAB improves survival of Salmonella in the presence of the antimicrobial peptide C18G. Furthermore, these macAB variants affect replication in macrophages and influence fitness during colonization of the murine gastrointestinal tract. Importantly, the infection outcome resulting from these macAB variants depends upon both the Salmonella Typhimurium genetic background and the host gene Nramp1, an important determinant of innate resistance to intracellular bacterial infection. The variations we have identified in the MacAB-TolC efflux pump in African iNTS may reflect evolution within human host populations that are compromised in their ability to clear intracellular Salmonella infections.


Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Proteínas de Bactérias/genética , Colite/patologia , Variação Genética , Macrófagos/imunologia , Salmonelose Animal/patologia , Salmonella typhimurium/imunologia , Transportadores de Cassetes de Ligação de ATP/metabolismo , Animais , Proteínas de Bactérias/metabolismo , Linhagem da Célula , Colite/induzido quimicamente , Colite/imunologia , Colite/microbiologia , Análise Mutacional de DNA , Modelos Animais de Doenças , Macrófagos/metabolismo , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos C57BL , Salmonelose Animal/imunologia , Salmonelose Animal/microbiologia , Replicação Viral
4.
Nat Commun ; 11(1): 4076, 2020 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-32796851

RESUMO

Group 3 innate lymphoid cells (ILC3) are an important regulator for immunity, inflammation and tissue homeostasis in the intestine, but how ILC3 activation is regulated remains elusive. Here we identify a new circular RNA (circRNA) circKcnt2 that is induced in ILC3s during intestinal inflammation. Deletion of circKcnt2 causes gut ILC3 activation and severe colitis in mice. Mechanistically, circKcnt2, as a nuclear circRNA, recruits the nucleosome remodeling deacetylase (NuRD) complex onto Batf promoter to inhibit Batf expression; this in turn suppresses Il17 expression and thereby ILC3 inactivation to promote innate colitis resolution. Furthermore, Mbd3-/-Rag1-/- and circKcnt2-/-Rag1-/- mice develop severe innate colitis following dextran sodium sulfate (DSS) treatments, while simultaneous deletion of Batf promotes colitis resolution. In summary, our data support a function of the circRNA circKcnt2 in regulating ILC3 inactivation and resolution of innate colitis.


Assuntos
Colite/imunologia , Colite/metabolismo , Linfócitos/metabolismo , Canais de Potássio Ativados por Sódio/metabolismo , RNA Circular/metabolismo , Animais , Colite/patologia , Proteínas de Ligação a DNA/genética , Modelos Animais de Doenças , Feminino , Proteínas de Homeodomínio/genética , Homeostase , Humanos , Imunidade Inata , Inflamação/imunologia , Inflamação/patologia , Intestinos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Camundongos Knockout , Canais de Potássio Ativados por Sódio/genética , RNA Circular/genética , RNA não Traduzido/genética , RNA não Traduzido/metabolismo , Fatores de Transcrição/genética
6.
PLoS One ; 15(7): e0235706, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32639988

RESUMO

During type 1 immune responses, CD4 T helper 1 (Th1) cells and CD8 T cells are activated via IL-12 and contribute to the elimination of intracellular pathogens through interferon gamma (IFNγ) production. In this study, we identified Placenta-specific 8 (Plac8) as a gene that is uniquely expressed in Th1 CD4 T cells relative to other CD4 T cell subsets and hypothesized that Plac8 may represent a novel therapeutic target in Th1 CD4 T cells. First, we determined that Plac8 mRNA in CD4 T cells was induced following IL-12 stimulation via an indirect route that required new protein synthesis. Upon evaluating the functional relevance of Plac8 expression in Th1 CD4 T cells, we discovered that Plac8 was important for suppressing IFNγ mRNA and protein production by CD4 T cells 24 hours after IL-12 stimulation, however Plac8 did not contribute to pathogenic CD4 T cell function during two models of intestinal inflammation. We also noted relatively high basal expression of Plac8 in CD8 T cells which could be further induced following IL-12 stimulation in CD8 T cells. Furthermore, Plac8 expression was important for establishing an optimal CD8 T cell response against influenza A virus via a T cell-intrinsic manner. Altogether, these results implicate Plac8 as a potential regulator of Th1 CD4 and CD8 T cell responses during Th1 T cell-driven inflammation.


Assuntos
Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Interferon gama/metabolismo , Proteínas/metabolismo , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Colite/imunologia , Colite/patologia , Modelos Animais de Doenças , Interferon gama/genética , Interleucina-12/farmacologia , Antígenos Comuns de Leucócito/genética , Antígenos Comuns de Leucócito/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infecções por Orthomyxoviridae/imunologia , Infecções por Orthomyxoviridae/patologia , Proteínas/genética , RNA Mensageiro/metabolismo , Regulação para Cima/efeitos dos fármacos
7.
Am J Med Sci ; 360(2): 176-191, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32553747

RESUMO

BACKGROUND: This study aimed to investigate the role of Clostridium butyricum (C. butyricum) in conjunction with the Toll-like receptor2 (TLR2) signaling pathway and T helper 17 (Th17) cells in dextran sodium sulfate (DSS)-induced colitis in mice. METHODS: Forty 8-week-old BALB/c mice were randomly divided into 5 groups of 8 mice for 7 days: control, DSS (5% DSS), DSS+C. butyricum (1 × 109 CFU), DSS+C. butyricum (1 × 108 CFU) and DSS+C. butyricum (1 × 107 CFU) groups. We assessed the disease activity index (DAI) and histological damage scores. The expression levels of TLR2, myeloid differentiation factor 88 (MyD88), nuclear factor kappa-B p65 (NF-κBp65), interleukin (IL) 17 (IL17), IL23 and retineic acid receptor related orphan nuclear receptor gamma t (RORγt) were determined through immunohistochemical staining, western blot and quantitative real-time PCR (qRT-PCR). The expression levels of CD3+CD4+IL17+ cells in peripheral blood were measured by flow cytometry. RESULTS: C. butyricum dose-dependently decreased DAI and histological damage scores in DSS mice and down-regulated the mRNA and protein levels of TLR2, MyD88 and NF-κBp65 in mouse colon tissue (all P < 0.05). In addition, C. butyricum dose-dependently decreased the levels of CD3+CD4+IL17+ cells in peripheral blood and down-regulated the mRNA and protein levels of IL17, IL23 and RORγt in mouse colon tissue (all P < 0.05). Moreover, the effect of C. butyricum on TLR2 was positively correlated with IL17, IL23 and RORγt. CONCLUSIONS: C. butyricum exerts a dose-dependently protective effect on acute intestinal inflammation induced by DSS in mice, by inhibiting the TLR2 signaling pathway, down-regulating the expression of IL23 and RORγt, and inhibiting the secretion of IL17.


Assuntos
Clostridium butyricum , Colite/imunologia , Fator 88 de Diferenciação Mieloide/imunologia , Probióticos , Células Th17/imunologia , Receptor 2 Toll-Like/imunologia , Fator de Transcrição RelA/imunologia , Animais , Peso Corporal , Colite/induzido quimicamente , Sulfato de Dextrana/toxicidade , Modelos Animais de Doenças , Comportamento de Ingestão de Líquido , Comportamento Alimentar , Feminino , Microbioma Gastrointestinal , Doenças Inflamatórias Intestinais/imunologia , Interleucina-17/genética , Interleucina-17/imunologia , Interleucina-17/metabolismo , Interleucina-23/genética , Interleucina-23/imunologia , Interleucina-23/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Fator 88 de Diferenciação Mieloide/genética , Fator 88 de Diferenciação Mieloide/metabolismo , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , RNA Mensageiro/metabolismo , Distribuição Aleatória , Transdução de Sinais , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Fator de Transcrição RelA/genética , Fator de Transcrição RelA/metabolismo
8.
Nature ; 583(7816): 447-452, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32499651

RESUMO

Genetic variations underlying susceptibility to complex autoimmune and allergic diseases are concentrated within noncoding regulatory elements termed enhancers1. The functions of a large majority of disease-associated enhancers are unknown, in part owing to their distance from the genes they regulate, a lack of understanding of the cell types in which they operate, and our inability to recapitulate the biology of immune diseases in vitro. Here, using shared synteny to guide loss-of-function analysis of homologues of human enhancers in mice, we show that the prominent autoimmune and allergic disease risk locus at chromosome 11q13.52-7 contains a distal enhancer that is functional in CD4+ regulatory T (Treg) cells and required for Treg-mediated suppression of colitis. The enhancer recruits the transcription factors STAT5 and NF-κB to mediate signal-driven expression of Lrrc32, which encodes the protein glycoprotein A repetitions predominant (GARP). Whereas disruption of the Lrrc32 gene results in early lethality, mice lacking the enhancer are viable but lack GARP expression in Foxp3+ Treg cells, which are unable to control colitis in a cell-transfer model of the disease. In human Treg cells, the enhancer forms conformational interactions with the promoter of LRRC32 and enhancer risk variants are associated with reduced histone acetylation and GARP expression. Finally, functional fine-mapping of 11q13.5 using CRISPR-activation (CRISPRa) identifies a CRISPRa-responsive element in the vicinity of risk variant rs11236797 capable of driving GARP expression. These findings provide a mechanistic basis for association of the 11q13.5 risk locus with immune-mediated diseases and identify GARP as a potential target in their therapy.


Assuntos
Cromossomos Humanos Par 11/genética , Colite/genética , Colite/imunologia , Elementos Facilitadores Genéticos/genética , Predisposição Genética para Doença/genética , Linfócitos T Reguladores/imunologia , Acetilação , Alelos , Animais , Cromossomos de Mamíferos/genética , Feminino , Fatores de Transcrição Forkhead/metabolismo , Histonas/metabolismo , Humanos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Sintenia/genética
9.
Nature ; 585(7826): 591-596, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32526765

RESUMO

Recent clinical and experimental evidence has evoked the concept of the gut-brain axis to explain mutual interactions between the central nervous system and gut microbiota that are closely associated with the bidirectional effects of inflammatory bowel disease and central nervous system disorders1-4. Despite recent advances in our understanding of neuroimmune interactions, it remains unclear how the gut and brain communicate to maintain gut immune homeostasis, including in the induction and maintenance of peripheral regulatory T cells (pTreg cells), and what environmental cues prompt the host to protect itself from development of inflammatory bowel diseases. Here we report a liver-brain-gut neural arc that ensures the proper differentiation and maintenance of pTreg cells in the gut. The hepatic vagal sensory afferent nerves are responsible for indirectly sensing the gut microenvironment and relaying the sensory inputs to the nucleus tractus solitarius of the brainstem, and ultimately to the vagal parasympathetic nerves and enteric neurons. Surgical and chemical perturbation of the vagal sensory afferents at the hepatic afferent level reduced the abundance of colonic pTreg cells; this was attributed to decreased aldehyde dehydrogenase (ALDH) expression and retinoic acid synthesis by intestinal antigen-presenting cells. Activation of muscarinic acetylcholine receptors directly induced ALDH gene expression in both human and mouse colonic antigen-presenting cells, whereas genetic ablation of these receptors abolished the stimulation of antigen-presenting cells in vitro. Disruption of left vagal sensory afferents from the liver to the brainstem in mouse models of colitis reduced the colonic pTreg cell pool, resulting in increased susceptibility to colitis. These results demonstrate that the novel vago-vagal liver-brain-gut reflex arc controls the number of pTreg cells and maintains gut homeostasis. Intervention in this autonomic feedback feedforward system could help in the development of therapeutic strategies to treat or prevent immunological disorders of the gut.


Assuntos
Encéfalo/citologia , Intestinos/citologia , Intestinos/inervação , Fígado/citologia , Fígado/inervação , Neurônios/fisiologia , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/imunologia , Vias Aferentes , Animais , Células Apresentadoras de Antígenos/imunologia , Colite/imunologia , Colite/metabolismo , Colite/patologia , Homeostase , Humanos , Intestinos/imunologia , Masculino , Camundongos , Ratos , Receptores Muscarínicos/metabolismo , Baço/citologia , Baço/imunologia , Nervo Vago/fisiologia
10.
PLoS One ; 15(5): e0233044, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32453801

RESUMO

Mice deficient in the transcription factor Runx3 develop a multitude of immune system defects, including early onset colitis. This paper demonstrates that Runx3 is expressed in colonic mononuclear phagocytes (MNP), including resident macrophages (RM) and dendritic cell subsets (cDC2). Runx3 deletion in MNP causes early onset colitis due to their impaired maturation. Mechanistically, the resulting MNP subset imbalance leads to up-regulation of pro-inflammatory genes as occurs in IL10R-deficient RM. In addition, RM and cDC2 display a marked decrease in expression of anti-inflammatory/TGF ß-regulated genes and ß-catenin signaling associated genes, respectively. MNP transcriptome and ChIP-seq data analysis suggest that a significant fraction of genes affected by Runx3 loss are direct Runx3 targets. Collectively, Runx3 imposes intestinal immune tolerance by regulating maturation of colonic anti-inflammatory MNP, befitting the identification of RUNX3 as a genome-wide associated risk gene for various immune-related diseases in humans, including gastrointestinal tract diseases such as Crohn's disease and celiac.


Assuntos
Colite/imunologia , Colo/imunologia , Subunidade alfa 3 de Fator de Ligação ao Core/genética , Sistema Fagocitário Mononuclear/imunologia , Animais , Diferenciação Celular , Colite/genética , Modelos Animais de Doenças , Humanos , Camundongos , Receptores de Interleucina-10/genética , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo , Regulação para Cima , beta Catenina/metabolismo
11.
Nat Commun ; 11(1): 2361, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32398640

RESUMO

The development of thymic regulatory T cells (Treg) is mediated by Aire-regulated self-antigen presentation on medullary thymic epithelial cells (mTECs) and dendritic cells (DCs), but the cooperation between these cells is still poorly understood. Here we show that signaling through Toll-like receptors (TLR) expressed on mTECs regulates the production of specific chemokines and other genes associated with post-Aire mTEC development. Using single-cell RNA-sequencing, we identify a new thymic CD14+Sirpα+ population of monocyte-derived dendritic cells (CD14+moDC) that are enriched in the thymic medulla and effectively acquire mTEC-derived antigens in response to the above chemokines. Consistently, the cellularity of CD14+moDC is diminished in mice with MyD88-deficient TECs, in which the frequency and functionality of thymic CD25+Foxp3+ Tregs are decreased, leading to aggravated mouse experimental colitis. Thus, our findings describe a TLR-dependent function of mTECs for the recruitment of CD14+moDC, the generation of Tregs, and thereby the establishment of central tolerance.


Assuntos
Colite/imunologia , Células Dendríticas/imunologia , Células Epiteliais/imunologia , Linfócitos T Reguladores/imunologia , Timo/imunologia , Transferência Adotiva , Animais , Apresentação do Antígeno , Autoantígenos/imunologia , Separação Celular , Quimiocinas/imunologia , Quimiocinas/metabolismo , Modelos Animais de Doenças , Células Epiteliais/metabolismo , Citometria de Fluxo , Receptores de Lipopolissacarídeos/metabolismo , Camundongos , Receptores Imunológicos/metabolismo , Tolerância a Antígenos Próprios , Análise de Sequência de RNA , Transdução de Sinais/imunologia , Análise de Célula Única , Linfócitos T Reguladores/transplante , Timo/citologia , Receptores Toll-Like/metabolismo , Regulação para Cima
12.
Nat Commun ; 11(1): 2608, 2020 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-32451418

RESUMO

IL-22 has dual functions during tumorigenesis. Short term IL-22 production protects against genotoxic stress, whereas uncontrolled IL-22 activity promotes tumor growth; therefore, tight regulation of IL-22 is essential. TGF-ß1 promotes the differentiation of Th17 cells, which are known to be a major source of IL-22, but the effect of TGF-ß signaling on the production of IL-22 in CD4+ T cells is controversial. Here we show an increased presence of IL-17+IL-22+ cells and TGF-ß1 in colorectal cancer compared to normal adjacent tissue, whereas the frequency of IL-22 single producing cells is not changed. Accordingly, TGF-ß signaling in CD4+ T cells (specifically Th17 cells) promotes the emergence of IL-22-producing Th17 cells and thereby tumorigenesis in mice. IL-22 single producing T cells, however, are not dependent on TGF-ß signaling. We show that TGF-ß, via AhR induction, and PI3K signaling promotes IL-22 production in Th17 cells.


Assuntos
Colite/complicações , Neoplasias do Colo/etiologia , Interleucinas/biossíntese , Células Th17/imunologia , Fator de Crescimento Transformador beta/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Carcinogênese/imunologia , Diferenciação Celular , Colite/imunologia , Neoplasias do Colo/imunologia , Neoplasias do Colo/patologia , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Feminino , Humanos , Interleucina-17/genética , Interleucina-17/metabolismo , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Fosfatidilinositol 3-Quinases/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Transdução de Sinais/imunologia , Células Th17/patologia , Fator de Crescimento Transformador beta1/metabolismo
13.
J Appl Microbiol ; 129(5): 1389-1401, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32473073

RESUMO

AIMS: To investigate the anti-inflammatory activity of an invasive and Hp65-producing strain Lactococcus lactis NCDO2118 FnBPA+ (pXYCYT:Hsp65) in acute 2,4,6-trinitrobenzene sulphonic acid (TNBS)-induced colitis in mice as an innovative therapeutic strategy against Crohn's disease (CD). METHODS AND RESULTS: The pXYCYT:Hsp65 plasmid was transformed into the L. lactis NCDO2118 FnBPA+ strain, resulting in the L. lactis NCDO2118 FnBPA+ (pXYCYT:Hsp65) strain. Then, the functionality of the strain was evaluated in vitro for Hsp65 production by Western blotting and for invasion into Caco-2 cells. The results demonstrated that the strain was able to produce Hsp65 and efficiently invade eukaryotic cells. Subsequently, in vivo, the anti-inflammatory capacity of the recombinant strain was evaluated in colitis induced with TNBS in BALB/c mice. Oral administration of the recombinant strain was able to attenuated the severity of colitis by mainly reducing IL-12 and IL-17 levels and increasing IL-10 and secretory immunoglobulin A levels. CONCLUSIONS: The L. lactis NCDO2118 FnBPA+ (pXYCYT:Hsp65) strain contributed to a reduction in inflammatory damage in experimental CD. SIGNIFICANCE AND IMPACT OF THE STUDY: This study, which used L. lactis for the production and delivery of Hsp65, has scientific relevance because it shows the efficacy of this new strategy based on therapeutic protein delivery into mammalian enterocytes.


Assuntos
Proteínas de Bactérias/metabolismo , Chaperonina 60/metabolismo , Colite/terapia , Imunoglobulina A Secretora/metabolismo , Interleucina-10/metabolismo , Lactococcus lactis/fisiologia , Administração Oral , Animais , Proteínas de Bactérias/genética , Células CACO-2 , Chaperonina 60/genética , Colite/induzido quimicamente , Colite/imunologia , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Inflamação/terapia , Lactococcus lactis/genética , Lactococcus lactis/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Ácido Trinitrobenzenossulfônico/toxicidade
14.
Nat Commun ; 11(1): 1522, 2020 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-32251280

RESUMO

Foxp3+ regulatory T (Treg) cells are essential for maintaining peripheral tolerance and preventing autoimmunity. While genetic factors may predispose for autoimmunity, additional environmental triggers, such as viral infections, are usually required to initiate the onset of disease. Here, we show that viral infection with LCMV results in type I IFN-dependent Treg cell loss that is rapidly compensated by the conversion and expansion of Vß5+ conventional T cells into iTreg cells. Using Vß5-deficient mice, we show that these Vß5+ iTreg cells are dispensable for limiting anti-viral immunity. Rather, the delayed replenishment of Treg cells in Vß5-deficient mice compromises suppression of microbiota-dependent activation of CD8+ T cells, resulting in colitis. Importantly, recovery from clinical symptoms in IBD patients is marked by expansion of the corresponding Vß2+ Treg population in humans. Collectively, we provide a link between a viral trigger and an impaired Treg cell compartment resulting in the initiation of immune pathology.


Assuntos
Infecções por Arenaviridae/imunologia , Autoimunidade , Linfócitos T CD8-Positivos/imunologia , Colite/imunologia , Vírus da Coriomeningite Linfocítica/imunologia , Linfócitos T Reguladores/imunologia , Animais , Infecções por Arenaviridae/complicações , Linhagem Celular , Colite/microbiologia , Colo/imunologia , Colo/microbiologia , Fatores de Transcrição Forkhead/metabolismo , Microbioma Gastrointestinal/imunologia , Voluntários Saudáveis , Interações entre Hospedeiro e Microrganismos/imunologia , Humanos , Interferon Tipo I/imunologia , Interferon Tipo I/metabolismo , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Ativação Linfocitária/genética , Masculino , Camundongos , Camundongos Knockout , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Linfócitos T Reguladores/metabolismo
15.
Biochem Biophys Res Commun ; 526(4): 1157-1163, 2020 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-32321642

RESUMO

The pathogenesis of inflammation bowel disease (IBD) involves exaggerated effector T cell responses and impaired regulatory T cell functions. We previously found that sauchinone (SAU) ameliorated experimental colitis via facilitating Th17 cell production of IL-10, but how SAU regulated Th17 cell differentiation remains unknown. MicroRNAs (miR) have been recognized as a crucial regulator of T cell biology and play a considerable role in IBD. Here, we demonstrated that SAU significantly suppressed miR-340 expression in Th17 cells, and enforced miR-340 expression abrogated SAU inhibition of Th17 differentiation. miR-340 itself was found to facilitate Th17 differentiation, especially the pathogenic "Th1-like" subset. In human IBD, miR-340 was intimately correlated with the disease severity. SAU markedly decreased miR-340 in the inflamed mucosa tissues from IBD patients. Scaffold/matrix-associated region-binding protein 1 (SMAR1) was identified as a target gene of miR-340. We revealed that blockade of miR-340 significantly reduced mucosal damage and Th17 responses in the lamina propria in a mouse colitis model. Our findings suggest that miR-340 negatively affects SAU inhibition of Th17 differentiation and might play a crucial role in the regulation of pathogenic "Th1-like" Th17 cell generation, which might serve as a novel therapeutic target of IBD.


Assuntos
Benzopiranos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Dioxóis/farmacologia , Inflamação/imunologia , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/imunologia , Intestinos/patologia , MicroRNAs/metabolismo , Células Th17/patologia , Sequência de Bases , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Colite/induzido quimicamente , Colite/imunologia , Colite/patologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Suscetibilidade a Doenças , Regulação para Baixo/efeitos dos fármacos , Fatores de Transcrição Forkhead/metabolismo , Humanos , MicroRNAs/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Índice de Gravidade de Doença , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Células Th1/efeitos dos fármacos , Células Th1/patologia , Células Th17/efeitos dos fármacos , Células Th17/imunologia , Ácido Trinitrobenzenossulfônico , Regulação para Cima/efeitos dos fármacos
16.
Adv Exp Med Biol ; 1244: 247-253, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32301019

RESUMO

Immune checkpoint inhibitors (ICIs) have shown significant benefit in cancer patients. Their success, however, is associated with immune-related adverse events (irAEs), which commonly affect the gastrointestinal tract, resulting in diarrhea and colitis. IrAEs range from mild self-limiting to severe life-threatening diseases and potentially limit the use of these medications. Diagnosis of ICI-induced enterocolitis is based on clinical symptoms, physical examination, stool tests, endoscopic and histologic evaluation, and/or imaging. Current management strategy is mainly anti-diarrheal agents for mild symptoms and immunosuppressants (e.g., corticosteroids, and infliximab or vedolizumab) for more severe diseases.


Assuntos
Colite/induzido quimicamente , Diarreia/induzido quimicamente , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/patologia , Imunoterapia/efeitos adversos , Neoplasias/tratamento farmacológico , Colite/tratamento farmacológico , Colite/imunologia , Colite/patologia , Diarreia/tratamento farmacológico , Diarreia/imunologia , Diarreia/patologia , Humanos , Neoplasias/imunologia
17.
PLoS One ; 15(3): e0228221, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32155151

RESUMO

Inflammatory bowel diseases (IBD) are complex, multifactorial disorders characterized by chronic relapsing intestinal inflammation. IBD is diagnosed around 1 in 1000 individuals in Western countries with globally increasing incident rates. Association studies have identified hundreds of genes that are linked to IBD and potentially regulate its pathology. The further dissection of the genetic network underlining IBD pathogenesis and pathophysiology is hindered by the limited capacity to functionally characterize each genetic association, including generating knockout animal models for every associated gene. Cutting-edge CRISPR/Cas9-based technology may transform the field of IBD research by efficiently and effectively introducing genetic alterations. In the present study, we used CRISPR/Cas9-based technologies to genetically modify hematopoietic stem cells. Through cell sorting and bone marrow transplantation, we established a system to knock out target gene expression by over 90% in the immune system of reconstituted animals. Using a CD40-mediated colitis model, we further validated our CRISPR/Cas9-based platform for investigating gene function in experimental IBD. In doing so, we developed a model system that delivers genetically modified mice in a manner much faster than conventional methodology, significantly reducing the time from target identification to in vivo target validation and expediting drug development.


Assuntos
Antígenos CD40/imunologia , Sistemas CRISPR-Cas/genética , Células-Tronco Hematopoéticas/metabolismo , Animais , Antígenos CD40/metabolismo , Colite/imunologia , Colite/terapia , Regulação da Expressão Gênica , Transplante de Células-Tronco Hematopoéticas , Camundongos
18.
BMC Biol ; 18(1): 29, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32183814

RESUMO

BACKGROUND: Immune checkpoint inhibitor (ICPI) can augment the anti-tumour response by blocking negative immunoregulators with monoclonal antibodies. The anti-cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) antibody is the first ICPI which has shown remarkable benefits in the clinical treatment of cancers. However, the increased activity of the immune system also causes some side effects called immune-related adverse events (irAEs). Colitis is one of the most common irAEs related to anti-CTLA-4 immunotherapy. RESULTS: We identified that CD4+ T cells were the primary responders in CTLA-4 blockade and that the expansion of gut-homing CD4+ T cells by anti-CTLA-4 therapy was independent of CD103. We used dextran sulfate sodium (DSS)-induced colitis mice as our model and tested the possibility of using a trafficking-blocking antibody to treat anti-CTLA-4 antibody-induced irAEs. We found that blocking T cell homing increased colitis severity in the context of CTLA-4 blockade and that gut-trafficking blockade had different effects on different Th subsets and could facilitate the proliferation of Th17 cells in the lamina propria (LP). CONCLUSIONS: Our data reveals the fundamental mechanism underlying trafficking-blocking antibody therapy for CTLA-4 blockade-induced colitis and provide a caution in regard to apply trafficking-blocking antibody treatment under CTLA-4 blockade condition.


Assuntos
Anticorpos Bloqueadores/farmacologia , Antígeno CTLA-4/antagonistas & inibidores , Colite/imunologia , Linfócitos T/imunologia , Animais , Colite/induzido quimicamente , Colite/patologia , Sulfato de Dextrana/efeitos adversos , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
19.
Sci Rep ; 10(1): 3829, 2020 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-32123204

RESUMO

Exposure to cigarette smoke (CS) causes detrimental health effects, increasing the risk of cardiovascular, pulmonary diseases and carcinogenesis in exposed individuals. The impact of CS on Inflammatory Bowel Disease (IBD) has been established by a number of epidemiological and clinical studies. In fact, CS is associated with a higher risk of developing Crohn's disease (CD) while inversely correlates with the development, disease risks, and relapse rate of ulcerative colitis (UC). To investigate the effect of CS exposure on experimental colitis, we performed a comprehensive and integrated comparative analysis of colon transcriptome and microbiome in mice exposed to dextran sodium sulfate (DSS) and CS. Colon transcriptome analysis revealed that CS downregulated specific pathways in a concentration-dependent manner, affecting both the inflammatory state and composition of the gut microbiome. Metagenomics analysis demonstrated that CS can modulate DSS-induced dysbiosis of specific bacterial genera, contributing to resolve the inflammation or accelerate recovery. The risks of smoking far outweigh any possible benefit, thus smoking cessation must always be encouraged because of its significant health benefits. However, the inverse association between active smoking and the development of UC cannot be ignored and the present study lays the foundation for investigating potential molecular mechanisms responsible for the attenuation of colitis by certain compounds of tobacco when decoupled from combustion.


Assuntos
Colite/imunologia , Colite/microbiologia , Sulfato de Dextrana/farmacologia , Fumaça/efeitos adversos , Produtos do Tabaco/efeitos adversos , Animais , Colite/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microbiota/efeitos dos fármacos
20.
Int J Med Microbiol ; 310(2): 151391, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32007342

RESUMO

Lactobacillus plantarum has been identified as a probiotic bacterium owing to its role in immune regulation and maintenance of intestinal permeability. Here, we investigated the anti-colitic effects and mechanism of L. plantarum CBT LP3 (LP3). This in vivo study was performed using dextran sodium sulfate (DSS) to induce colitis in mice. Mice were randomly divided into three groups: a control supplied with normal drinking water, a DSS-treated group followed by oral administration of vehicle, and a DSS-treated group gavaged with LP3 daily for 7 days following DSS administration. An analysis of macrophages and T cell subsets harvesting from peritonium cavity cells and splenocytes was performed using a flow cytometric assay. Gene expression and cytokine profiles were measured using quantitative reverse transcriptase polymerase chain reaction. The administration of LP3 significantly attenuated disease activity and histolopathology compared to control. LP3 had anti-inflammatory effects, with increased induction of regulatory T cells and type 2 helper T cells in splenocytes and restoration of goblet cells accompanied by suppression of proinflammatory cytokine expressions. These findings suggest that L. plantarum CBT LP3 can be used as a potent immunomodulator, which has significant implications for IBD treatment.


Assuntos
Colite/imunologia , Colite/terapia , Lactobacillus plantarum , Probióticos/uso terapêutico , Subpopulações de Linfócitos T/imunologia , Animais , Colite/induzido quimicamente , Citocinas/imunologia , Sulfato de Dextrana , Modelos Animais de Doenças , Fatores Imunológicos/uso terapêutico , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Linfócitos T Reguladores/imunologia , Células Th2/imunologia
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