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1.
J Environ Pathol Toxicol Oncol ; 39(3): 235-245, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32865915

RESUMO

Ulcerative colitis (UC) is an intractable ailment, in which may chronic inflammations/ulcerations may develop in the mucosal lining of the colon with multiple recurrences. Various drugs such as steroids, immunosuppressants, and antibiotics are extensively used to treat UC. The patients suffer from adverse effects of these advanced drugs. So, they need a harmless therapeutic agent from natural sources. The therapeutic D-carvone has an anti-inflammatory action against the investigational colon cancer models. Therefore, we analyzed the effect of D-carvone on dextran sulfate sodium (DSS) provoked colitis model in mice as follows: Group I: noncolitis healthy control mice; Group II: ulcerative colitis mice models; Group III: D-carvone (40 mg/kg) + ulcerative colitis models; Group IV: sulfasalazine (50 mg/kg) + ulcerative colitis models. On the 8th day, the experimental study was terminated and serum samples and colon tissues were processed for further analysis. The effect of D-carvone at different concentration was studied on the LPS challenged RAW 264.7 cell lines. The D-carvone (40 mg/kg) treatment maintained the colon length and decreased disease activity index (DAI) score in UC animals. The increased antioxidant enzymes status and decreased oxidative stress and pro-inflammatory markers were noted in the D-carvone (40 mg/ kg) + UC mice. Histopathological study of colon tissue of D-carvone (40 mg/kg) treated UC mice displayed less mucosal damage and improved crypt integrity and goblet cells compared with DSS only provoked mice. The im-munohistochemical expression of iNOS and COX-2 was drastically diminished in the D-carvone treated UC mice. D-carvone (40 mg/kg) treatment appreciably diminished the LPS provoked NO production and pro-inflammatory modulators in the RAW 264.7 macrophage cell lines. These findings proved that D-carvone has a potential therapeutic effect to prevent LPS induced inflammation in in vitro cells and chemically induced ulcerative colitis in vivo models.


Assuntos
Anti-Inflamatórios/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Monoterpenos Cicloexânicos/uso terapêutico , Ciclo-Oxigenase 2/metabolismo , Macrófagos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fator de Necrose Tumoral alfa/sangue , Animais , Anti-Inflamatórios/administração & dosagem , Sobrevivência Celular/efeitos dos fármacos , Colite Ulcerativa/imunologia , Colite Ulcerativa/patologia , Colo/efeitos dos fármacos , Colo/imunologia , Colo/patologia , Monoterpenos Cicloexânicos/administração & dosagem , Sulfato de Dextrana , Modelos Animais de Doenças , Lipopolissacarídeos , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7
2.
PLoS One ; 15(8): e0238006, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32857814

RESUMO

This study aimed to evaluate the effects of two prebiotics in different concentrations on nutrient digestibility, fermentative products and immunological variables in adult dogs. Twenty-four adult dogs were randomly divided into six blocks according to their metabolic body weights (BW0.75); within these groups, dogs were randomized to four treatments: control without prebiotics (CO); inclusion of 0.5% prebiotic blend Yes-Golf (B1); inclusion of 1.0% galactooligosaccharide (GOS); and inclusion of 1.0% prebiotic blend Yes-Golf (B2). The experiment lasted 30 days, with 20 days adaptation and 10 days stool and blood collection. Results were analyzed for normality and means were separated by ANOVA and adjusted by the Tukey test at the significance level of 5.0%. Prebiotic supplementation had no effect on apparent digestibility coefficients (ADC), total stool production and fecal scores (p > 0.05). Prebiotics evaluated also did not alter fecal pH, nor the concentrations of ammonia, lactic acid, short chain fatty acids (SCFA) and most fecal branched chain fatty acids (BCFA) (p > 0.05). The addition of GOS decreased the concentration of iso-valeric acid (p = 0.0423). Regarding immunological variables, concentrations of fecal IgA were not influenced by the treatments. Treatments GOS and B2 increased the total number of polymorphonuclear cells, as well as the oxidative burst in relation to treatments B1 and CO (p < 0.0001). Treatment B2 improved the rate of S. aureus phagocytosis in relation to CO (p = 0.0111), and both the GOS and B2 treatments had a better index for E. coli phagocytosis than the CO treatment (p = 0.0067). In conclusion, there was indication that both prebiotics GOS and B2 at 1.0% inclusion improved the immunity of healthy dogs.


Assuntos
Colo/efeitos dos fármacos , Oligossacarídeos/farmacologia , Prebióticos , Animais , Colo/imunologia , Colo/microbiologia , Dieta/veterinária , Cães , Ácidos Graxos Voláteis/análise , Fezes/química , Microbioma Gastrointestinal/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Leucócitos/citologia , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Fagocitose/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Staphylococcus aureus/fisiologia
3.
Cell Rep ; 32(1): 107863, 2020 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-32610043

RESUMO

Severe acute respiratory syndrome-related coronavirus-2 (SARS-CoV-2) is an unprecedented worldwide health problem that requires concerted and global approaches to stop the coronavirus 2019 (COVID-19) pandemic. Although SARS-CoV-2 primarily targets lung epithelium cells, there is growing evidence that the intestinal epithelium is also infected. Here, using both colon-derived cell lines and primary non-transformed colon organoids, we engage in the first comprehensive analysis of the SARS-CoV-2 life cycle in human intestinal epithelial cells (hIECs). Our results demonstrate that hIECs fully support SARS-CoV-2 infection, replication, and production of infectious de novo virus particles. We found that viral infection elicits an extremely robust intrinsic immune response where interferon-mediated responses are efficient at controlling SARS-CoV-2 replication and de novo virus production. Taken together, our data demonstrate that hIECs are a productive site of SARS-CoV-2 replication and suggest that the enteric phase of SARS-CoV-2 may participate in the pathologies observed in COVID-19 patients by contributing to increasing patient viremia and fueling an exacerbated cytokine response.


Assuntos
Betacoronavirus/crescimento & desenvolvimento , Colo/virologia , Células Epiteliais/imunologia , Interferons/imunologia , Mucosa Intestinal/imunologia , Betacoronavirus/imunologia , Células CACO-2 , Linhagem Celular Tumoral , Colo/citologia , Colo/imunologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/patologia , Síndrome da Liberação de Citocina/imunologia , Síndrome da Liberação de Citocina/virologia , Citocinas/sangue , Células Epiteliais/virologia , Humanos , Mucosa Intestinal/citologia , Mucosa Intestinal/virologia , Pandemias , Pneumonia Viral/imunologia , Pneumonia Viral/patologia , Síndrome Respiratória Aguda Grave/imunologia , Síndrome Respiratória Aguda Grave/patologia , Replicação Viral/imunologia
4.
Am J Surg Pathol ; 44(8): 1130-1136, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32590456

RESUMO

The absence of neuroendocrine (NE) cells in the intestinal mucosa in autoimmune enteropathy (AIE) has been occasionally reported. However, the status of NE cells has not been studied in detail in AIE. Small bowel and colonic biopsies were retrospectively retrieved from 18 AIE patients (26 baseline [18 small bowel and 8 colon]; and 15 follow-up [11 duodenum and 4 colon] biopsies in 11 patients). Thirty-three common variable immunodeficiency (CVID) patients (30 small bowel and 16 colon), 15 inflammatory bowel disease patients (5 duodenum and 10 colon), 13 immunoglobulinA deficiency patients (13 duodenum and 5 colon), and 10 normal controls (5 colon and 5 duodenum) were selected as control groups. Histologic features (villous atrophy, intraepithelial lymphocytosis, acute inflammation, crypt apoptosis, and absence or presence of goblet cells, Paneth cells and plasma cells) were recorded. Chromogranin immunostain was performed and chromogranin-positive NE cells were counted per 10 consecutive, well-oriented crypts. On the basis of the number of chromogranin-positive NE cells, cases were graded as being absent (≤3 NE cells), markedly decreased (≤15), and intact (>15). The NE cell status correlated with histologic features. The median age of 18 AIE patients was 38.5 years (range: 11 to 74 y) and 14 patients were male. Fourteen of 18 (78%) patients showed loss (absent or markedly decreased) of NE cells in the small bowel and/or colon in the baseline biopsies including 12 (of 18) small bowel and 6 (of 8) colon biopsies. Follow-up biopsy was available in 11 patients. Six of 7 (85%) patients who showed loss of NE cells in the baseline biopsies regained NE cells in the follow-up biopsies, and 1 patient continued to show loss of NE cells. Four patients who showed intact NE cells in the baseline remained unchanged in the follow-up. Among the control groups, 3 of 33 (9%) CVID patients showed loss of NE cells. NE cells were not lost in the biopsies of all 15 and 13 patients with inflammatory bowel disease and immunoglobulinA deficiency, respectively, or the 10 normal controls. In all 41 biopsies (26 baseline plus 15 follow-up) with AIE, NE cell loss was significantly associated with increased crypt apoptosis and loss of goblet cells (P=0.001, both) but not with other histologic findings. In conclusion, our study suggests that NE cells may also be the target cells in AIE and commonly lost in the intestinal crypts in AIE, and consequently loss of NE cells can be used as an adjunct histologic feature for diagnosis of AIE.


Assuntos
Colo/patologia , Mucosa Intestinal/patologia , Intestino Delgado/patologia , Células Neuroendócrinas/patologia , Poliendocrinopatias Autoimunes/patologia , Adolescente , Adulto , Idoso , Biomarcadores/análise , Biópsia , Criança , Cromograninas/análise , Colo/química , Colo/imunologia , Bases de Dados Factuais , Feminino , Humanos , Imuno-Histoquímica , Mucosa Intestinal/química , Mucosa Intestinal/imunologia , Intestino Delgado/química , Intestino Delgado/imunologia , Masculino , Pessoa de Meia-Idade , Células Neuroendócrinas/química , Células Neuroendócrinas/imunologia , Poliendocrinopatias Autoimunes/imunologia , Poliendocrinopatias Autoimunes/metabolismo , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos , Adulto Jovem
5.
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
6.
PLoS Pathog ; 16(5): e1008553, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32453761

RESUMO

IRGM and its mouse orthologue Irgm1 are dynamin-like proteins that regulate vesicular remodeling, intracellular microbial killing, and pathogen immunity. IRGM dysfunction is linked to inflammatory bowel disease (IBD), and while it is thought that defective intracellular killing of microbes underscores IBD susceptibility, studies have yet to address how IRGM/Irgm1 regulates immunity to microbes relevant to intestinal inflammation. Here we find that loss of Irgm1 confers marked susceptibility to Citrobacter rodentium, a noninvasive intestinal pathogen that models inflammatory responses to intestinal bacteria. Irgm1-deficient mice fail to control C. rodentium outgrowth in the intestine, leading to systemic pathogen spread and host mortality. Surprisingly, susceptibility due to loss of Irgm1 function was not linked to defective intracellular killing of C. rodentium or exaggerated inflammation, but was instead linked to failure to remodel specific colon lamina propria (C-LP) myeloid cells that expand in response to C. rodentium infection and are essential for C. rodentium immunity. Defective immune remodeling was most striking in C-LP monocytes, which were successfully recruited to the infected C-LP, but subsequently underwent apoptosis. Apoptotic susceptibility was induced by C. rodentium infection and was specific to this setting of pathogen infection, and was not apparent in other settings of intestinal inflammation. These studies reveal a novel role for Irgm1 in host defense and suggest that deficiencies in survival and remodeling of C-LP myeloid cells that control inflammatory intestinal bacteria may underpin IBD pathogenesis linked to IRGM dysfunction.


Assuntos
Citrobacter rodentium/imunologia , Colo/imunologia , Infecções por Enterobacteriaceae/imunologia , Proteínas de Ligação ao GTP/deficiência , Doenças Inflamatórias Intestinais/imunologia , Monócitos/imunologia , Animais , Colo/microbiologia , Colo/patologia , Infecções por Enterobacteriaceae/genética , Infecções por Enterobacteriaceae/patologia , Proteínas de Ligação ao GTP/imunologia , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/microbiologia , Doenças Inflamatórias Intestinais/patologia , Camundongos , Camundongos Knockout , Monócitos/microbiologia , Monócitos/patologia , Membrana Mucosa/imunologia , Membrana Mucosa/microbiologia , Membrana Mucosa/patologia
7.
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
8.
Nat Commun ; 11(1): 1512, 2020 03 23.
Artigo em Inglês | MEDLINE | ID: mdl-32251296

RESUMO

Studies of inflammatory bowel disease (IBD) have been inconclusive in relating microbiota with distribution of inflammation. We report microbiota, host transcriptomics, epigenomics and genetics from matched inflamed and non-inflamed colonic mucosa [50 Crohn's disease (CD); 80 ulcerative colitis (UC); 31 controls]. Changes in community-wide and within-patient microbiota are linked with inflammation, but we find no evidence for a distinct microbial diagnostic signature, probably due to heterogeneous host-microbe interactions, and show only marginal microbiota associations with habitual diet. Epithelial DNA methylation improves disease classification and is associated with both inflammation and microbiota composition. Microbiota sub-groups are driven by dominant Enterbacteriaceae and Bacteroides species, representative strains of which are pro-inflammatory in vitro, are also associated with immune-related epigenetic markers. In conclusion, inflamed and non-inflamed colonic segments in both CD and UC differ in microbiota composition and epigenetic profiles.


Assuntos
Colite Ulcerativa/imunologia , Doença de Crohn/imunologia , Epigênese Genética/imunologia , Microbioma Gastrointestinal/imunologia , Interações entre Hospedeiro e Microrganismos/imunologia , Adulto , Idoso , Bacteroides/genética , Bacteroides/imunologia , Bacteroides/isolamento & purificação , Biópsia , Células CACO-2 , Estudos de Casos e Controles , Estudos de Coortes , Colite Ulcerativa/genética , Colite Ulcerativa/microbiologia , Colite Ulcerativa/patologia , Colo/diagnóstico por imagem , Colo/imunologia , Colo/microbiologia , Colo/patologia , Colonoscopia , Doença de Crohn/genética , Doença de Crohn/microbiologia , Doença de Crohn/patologia , DNA Bacteriano/isolamento & purificação , Enterobacteriaceae/genética , Enterobacteriaceae/imunologia , Enterobacteriaceae/isolamento & purificação , Epigenômica , Feminino , Microbioma Gastrointestinal/genética , Interações entre Hospedeiro e Microrganismos/genética , Humanos , Mucosa Intestinal/diagnóstico por imagem , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade , RNA Ribossômico 16S/genética , RNA-Seq , Adulto Jovem
9.
Cancer Treat Res ; 180: 197-211, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32215871

RESUMO

Colorectal cancer (CRC) represents a major public health challenges, with one of the highest incidences worldwide. The two affected anatomical sites in CRC, i.e. the colon and the rectum, share important underlying features, but often differ in terms of therapeutic management. Current guidelines for CRC define its clinical stratification according to classical, tumor cell-based and pathological parameters. Novel ground-breaking findings in the recent years revealed the prominent role of the immune system in shaping CRC development. This chapter provides a detailed overview of the main genomic and immune features driving (or hampering) CRC progression, with a focus on the main immune cells and factors shaping its evolution. Furthermore, we discuss how tumor-infiltrating immunity could be leveraged both for therapeutic and stratification purposes.


Assuntos
Colo/imunologia , Neoplasias Colorretais/imunologia , Linfócitos do Interstício Tumoral/imunologia , Reto/imunologia , Colo/patologia , Progressão da Doença , Humanos , Reto/patologia
10.
Toxicology ; 435: 152410, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-32068018

RESUMO

Epidemiologic studies show that the levels of air pollutants and particulate matter are positively associated with the morbidity and mortality of cardiovascular diseases. Here we demonstrate that the intratracheal instillation of multi-walled carbon nanotubes (MWCNTs), a standard fine particle, exacerbate doxorubicin (DOX)-induced cardiotoxicity in mice through altering gut microbiota and pulmonary and colonic macrophage phenotype. MWCNTs (25 µg/kg per day, 5 days a week for 3 weeks) promoted cardiotoxicity and apoptosis in the DOX (2 mg/kg, twice a week for 5 weeks)-treated C57BL/6 mice. MWCNTs exaggerated DOX-induced gut microbiota dysbiosis characterized by the increased abundances of Helicobacteraceae and Coriobacteriaceae. In addition, MWCNTs promoted DOX-induced M1-like polarization of colonic macrophages with an increase in TNF-α, IL-1ß and CC chemokine ligand 2 in peripheral blood. Importantly, treatment with the antibiotics attenuated MWCNTs plus DOX-induced apoptosis of cardiomyocytes and M1-like polarization of colonic macrophages. The fecal microbiota transplantation demonstrated that MWCNTs exaggerated DOX-induced cardiotoxicity with M1-like polarization of colonic macrophages. The conditioned medium from MWCNTs-treated pulmonary macrophages promoted DOX-induced gut microbiota dysbiosis and colonic macrophage polarization. Furthermore, the co-culture of macrophages and fecal bacteria promoted M1-like macrophage polarization and their production of TNF-α and IL-1ß, and thereby exacerbated the effects of MWCNTs. Moreover, IL-1ß and TNF-α blockade, either alone or in combination attenuated MWCNTs-exacerbated cardiotoxicity. In summary, MWCNTs exacerbate DOX-induced cardiotoxicity in mice through gut microbiota and pulmonary and colonic macrophage interaction. Our findings identify a novel mechanism of action of inhaled particle-driven cardiotoxicity.


Assuntos
Antibióticos Antineoplásicos/toxicidade , Colo/efeitos dos fármacos , Doxorrubicina/toxicidade , Microbioma Gastrointestinal/efeitos dos fármacos , Cardiopatias/induzido quimicamente , Pulmão/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Nanotubos de Carbono/toxicidade , Animais , Antibacterianos/farmacologia , Apoptose/efeitos dos fármacos , Células Cultivadas , Quimiocina CCL2/sangue , Colo/imunologia , Colo/metabolismo , Colo/microbiologia , Disbiose , Fezes/microbiologia , Cardiopatias/sangue , Cardiopatias/imunologia , Cardiopatias/microbiologia , Interleucina-1beta/sangue , Pulmão/imunologia , Pulmão/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Fenótipo , Fator de Necrose Tumoral alfa/sangue
11.
Nat Immunol ; 21(3): 343-353, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32066951

RESUMO

Gastrointestinal microbiota and immune cells interact closely and display regional specificity; however, little is known about how these communities differ with location. Here, we simultaneously assess microbiota and single immune cells across the healthy, adult human colon, with paired characterization of immune cells in the mesenteric lymph nodes, to delineate colonic immune niches at steady state. We describe distinct helper T cell activation and migration profiles along the colon and characterize the transcriptional adaptation trajectory of regulatory T cells between lymphoid tissue and colon. Finally, we show increasing B cell accumulation, clonal expansion and mutational frequency from the cecum to the sigmoid colon and link this to the increasing number of reactive bacterial species.


Assuntos
Colo/imunologia , Colo/microbiologia , Microbioma Gastrointestinal/imunologia , Adulto , Linfócitos B/imunologia , Colo/citologia , Humanos , Mucosa Intestinal/citologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Linfonodos/citologia , Linfonodos/imunologia , Ativação Linfocitária , Especificidade de Órgãos , RNA-Seq , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Reguladores/imunologia , Transcriptoma
12.
J Virol ; 94(9)2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32051277

RESUMO

Chronic, low-grade, systemic, and mucosal inflammation correlates with increased morbidity and poor clinical outcomes among patients living with human immunodeficiency virus (HIV). These long-term complications are linked to the disruption of gastrointestinal (GI) tract epithelial barrier integrity and subsequent microbial translocation. However, the mechanisms responsible for these downstream effects of infection are unknown. Here, we demonstrate that during the disruption of the GI tract and increased microbial translocation, we find inflammatory cytokines (e.g., interferon gamma [IFN-γ] and tumor necrosis factor alpha [TNF-α]) produced by innate lymphoid cells (ILCs) located in the colon secondary to simian immunodeficiency virus (SIV) infection. To do this, we used viably cryopreserved colon cells from SIV-infected and uninfected rhesus macaque monkeys and determined the make-up of the ILC subpopulations and the cytokines they expressed constitutively. Our studies revealed that the interleukin-22 (IL-22)/IL-17-producing ILCS was not altered during SIV infection. However, the percentage of IFN-γ+ ILCs in infected colons was 5- to 10-fold higher than that in uninfected colons. ILCs from infected tissue that produced IFN-γ also expressed TNF-α and IL-22. The coexpression of inflammatory cytokines with IL-22 is linked to the ability of ILCs to coexpress T-bet and RORγT/Ahr. The expression of IFN-γ/TNF-α by ILCs and NK cells combined likely triggers a pathway that contributes to chronic mucosal inflammation, GI barrier breakdown, and microbial translocation within the context of SIV/HIV infection.IMPORTANCE There is a slow yet significant uptick in systemic inflammation secondary to HIV infection that has long-term consequences for the infected host. The systemic inflammation most likely occurs as a consequence of the disruption of the gut epithelial barrier, leading to the translocation of gut microbial products. This disruption may result from mucosal inflammation. Here, we show in an animal model of HIV that chronic SIV-infected gut contains innate lymphoid cells producing inflammatory cytokines.


Assuntos
Linfócitos/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Vírus da Imunodeficiência Símia/metabolismo , Animais , Colo/imunologia , Citocinas/imunologia , Feminino , Imunidade Inata/imunologia , Inflamação/patologia , Interferon gama/metabolismo , Interleucina-17/metabolismo , Interleucinas/metabolismo , Mucosa Intestinal/virologia , Células Matadoras Naturais/metabolismo , Linfócitos/metabolismo , Macaca mulatta/virologia , Masculino , Síndrome de Imunodeficiência Adquirida dos Símios/metabolismo , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/patogenicidade , Fator de Necrose Tumoral alfa/metabolismo
13.
Nat Commun ; 11(1): 900, 2020 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-32060280

RESUMO

Copper levels are known to be elevated in inflamed and malignant tissues. But the mechanism underlying this selective enrichment has been elusive. In this study, we report a axis by which inflammatory cytokines, such as IL-17, drive cellular copper uptake via the induction of a metalloreductase, STEAP4. IL-17-induced elevated intracellular copper level leads to the activation of an E3-ligase, XIAP, which potentiates IL-17-induced NFκB activation and suppresses the caspase 3 activity. Importantly, this IL-17-induced STEAP4-dependent cellular copper uptake is critical for colon tumor formation in a murine model of colitis-associated tumorigenesis and STEAP4 expression correlates with IL-17 level and XIAP activation in human colon cancer. In summary, this study reveals a IL-17-STEAP4-XIAP axis through which the inflammatory response induces copper uptake, promoting colon tumorigenesis.


Assuntos
Colo/imunologia , Neoplasias do Colo/imunologia , Cobre/metabolismo , Proteínas Inibidoras de Apoptose/imunologia , Interleucina-17/imunologia , Proteínas de Membrana/imunologia , Animais , Carcinogênese , Colite/genética , Colite/imunologia , Colite/metabolismo , Colo/metabolismo , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Cobre/imunologia , Humanos , Proteínas Inibidoras de Apoptose/genética , Interleucina-17/genética , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
14.
Am J Pathol ; 190(4): 874-885, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32035057

RESUMO

Intercellular adhesion molecule-1 (ICAM-1) is up-regulated during inflammation by several cell types. ICAM-1 is best known for its role in mediating leukocyte adhesion to endothelial cells and guiding leukocytes across the vascular wall. Recently, macrophages have been shown to express ICAM-1, however, their role in macrophage function is unclear. We found that ICAM-1 expression was induced during inflammatory macrophage polarization and high numbers of ICAM-1-expressing macrophages were noted in inflamed colon tissue in a murine colitis model and in human inflammatory bowel disease. Because tissue macrophages play a critical role in removing apoptotic/necrotic cells in inflammation and injury, a process termed efferocytosis, it was examined whether ICAM-1 contributes to this process. Genetic deletion (ICAM-1 knockout mice) or siRNA-mediated knockdown of ICAM-1 in isolated murine and human macrophages significantly impaired apoptotic cell (AC) engulfment. Impairment in the engulfment of Jurkat T cells, neutrophils, and epithelial cells was confirmed ex vivo by inflammatory macrophages and in vivo by thioglycolate-recruited peritoneal macrophages. Decreased efferocytosis was also seen in vitro and in vivo with inhibition of ICAM-1 adhesive interactions, using a function blocking anti-ICAM-1 antibody. Mechanistically, it was found that ICAM-1 actively redistributes to cluster around engulfed ACs to facilitate macrophage-AC binding. Our findings define a new role for ICAM-1 in promoting macrophage efferocytosis, a critical process in the resolution of inflammation and restoration of tissue homeostasis.


Assuntos
Colo/imunologia , Inflamação/imunologia , Molécula 1 de Adesão Intercelular/fisiologia , Macrófagos/imunologia , Fagocitose , Animais , Apoptose , Adesão Celular , Colo/metabolismo , Colo/patologia , Humanos , Inflamação/metabolismo , Inflamação/patologia , Macrófagos/metabolismo , Macrófagos/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
15.
Parasite Immunol ; 42(4): e12698, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31976564

RESUMO

Immunomodulatory molecules produced by helminth parasites are receiving much attention recently as novel therapeutic agents for inflammation and autoimmune diseases. In this study, we show that macrophage migration inhibitory factor (MIF) homologue from the filarial parasite, Wuchereria bancrofti (rWbaMIF-2), can suppress inflammation in a dextran sulphate sodium salt (DSS)-induced colitis model. The disease activity index (DAI) in DSS given mice showed loss of body weight and bloody diarrhoea. At autopsy, colon of these mice showed severe inflammation and reduced length. Administration of rWbaMIF-2 significantly reduced the DAI in DSS-induced colitis mice. rWbaMIF-2-treated mice had no blood in the stools, and their colon length was similar to the normal colon with minimal inflammation and histological changes. Pro-inflammatory cytokine genes (TNF-α, IL-6, IFN-γ, IL-1ß, IL-17A and NOS2) were downregulated in the colon tissue and peritoneal macrophages of rWbaMIF-2-treated mice. However, there were significant increases in IL-10-producing Treg and B1 cells in the colon and peritoneal cavity of rWbaMIF-2-treated mice. These findings suggested that rWbaMIF-2 treatment significantly ameliorated the clinical symptoms, inflammation and colon pathology in DSS given mice. This immunomodulatory effect of rWbaMIF-2 appeared to be by promoting the infiltration of Treg cells into the colon.


Assuntos
Colite/tratamento farmacológico , Oxirredutases Intramoleculares/uso terapêutico , Fatores Inibidores da Migração de Macrófagos/uso terapêutico , Wuchereria bancrofti , Animais , Colite/induzido quimicamente , Colite/imunologia , Colite/metabolismo , Colo/imunologia , Colo/metabolismo , Sulfato de Dextrana , Feminino , Inflamação/tratamento farmacológico , Interleucina-17/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Fator de Necrose Tumoral alfa/metabolismo
16.
Gastroenterology ; 158(5): 1373-1388, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31917256

RESUMO

BACKGROUND & AIMS: Colibactin-producing Escherichia coli (CoPEC) colonize the colonic mucosa of a higher proportion of patients with vs without colorectal cancer (CRC) and promote colorectal carcinogenesis in susceptible mouse models of CRC. Autophagy degrades cytoplasmic contents, including intracellular pathogens, via lysosomes and regulates intestinal homeostasis. We investigated whether inhibiting autophagy affects colorectal carcinogenesis in susceptible mice infected with CoPEC. METHODS: Human intestinal epithelial cells (IECs) (HCT-116) were infected with a strain of CoPEC (11G5 strain) isolated from a patient or a mutant strain that does not produce colibactin (11G5ΔclbQ). Levels of ATG5, ATG16L1, and SQSTM1 (also called p62) were knocked down in HCT-116 cells using small interfering RNAs. ApcMin/+ mice and ApcMin/+ mice with IEC-specific disruption of Atg16l1 (ApcMin/+/Atg16l1ΔIEC) were infected with 11G5 or 11G5ΔclbQ. Colonic tissues were collected from mice and analyzed for tumor size and number and by immunohistochemical staining, immunoblot, and quantitative reverse transcription polymerase chain reaction for markers of autophagy, DNA damage, cell proliferation, and inflammation. We analyzed levels of messenger RNAs (mRNAs) encoding proteins involved in autophagy in colonic mucosal tissues from patients with sporadic CRC colonized with vs without CoPEC by quantitative reverse-transcription polymerase chain reaction. RESULTS: Patient colonic mucosa with CoPEC colonization had higher levels of mRNAs encoding proteins involved in autophagy than colonic mucosa without these bacteria. Infection of cultured IECs with 11G5 induced autophagy and DNA damage repair, whereas infection with 11G5ΔclbQ did not. Knockdown of ATG5 in HCT-116 cells increased numbers of intracellular 11G5, secretion of interleukin (IL) 6 and IL8, and markers of DNA double-strand breaks but reduced markers of DNA repair, indicating that autophagy is required for bacteria-induced DNA damage repair. Knockdown of ATG5 in HCT-116 cells increased 11G5-induced senescence, promoting proliferation of uninfected cells. Under uninfected condition, ApcMin/+/Atg16l1ΔIEC mice developed fewer and smaller colon tumors than ApcMin/+ mice. However, after infection with 11G5, ApcMin/+/Atg16l1ΔIEC mice developed more and larger tumors, with a significant increase in mean histologic score, than infected ApcMin/+ mice. Increased levels of Il6, Tnf, and Cxcl1 mRNAs, decreased level of Il10 mRNA, and increased markers of DNA double-strand breaks and proliferation were observed in the colonic mucosa of 11G5-infected ApcMin/+/Atg16l1ΔIEC mice vs 11G5-infected ApcMin/+ mice. CONCLUSION: Infection of IECs and susceptible mice with CoPEC promotes autophagy, which is required to prevent colorectal tumorigenesis. Loss of ATG16L1 from IECs increases markers of inflammation, DNA damage, and cell proliferation and increases colorectal tumorigenesis in 11G5-infected ApcMin/+ mice. These findings indicate the importance of autophagy in response to CoPEC infection, and strategies to induce autophagy might be developed for patients with CRC and CoPEC colonization.


Assuntos
Autofagia , Carcinogênese/imunologia , Colo/microbiologia , Neoplasias do Colo/imunologia , Mucosa Intestinal/microbiologia , Proteína da Polipose Adenomatosa do Colo/genética , Animais , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/imunologia , Proteínas Relacionadas à Autofagia/metabolismo , Carcinogênese/efeitos dos fármacos , Proliferação de Células , Colo/imunologia , Colo/patologia , Neoplasias do Colo/genética , Neoplasias do Colo/microbiologia , Neoplasias do Colo/patologia , Modelos Animais de Doenças , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/imunologia , Células Epiteliais/patologia , Escherichia coli/imunologia , Escherichia coli/isolamento & purificação , Escherichia coli/patogenicidade , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Células HCT116 , Células HeLa , Interações Hospedeiro-Patógeno/imunologia , Humanos , Mucosa Intestinal/imunologia , Mucosa Intestinal/patologia , Camundongos , Camundongos Transgênicos , Peptídeos/toxicidade , Policetídeos/toxicidade , RNA Interferente Pequeno/metabolismo
18.
J Immunol ; 204(4): 980-989, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31889022

RESUMO

Altered intestinal epithelial integrity is an important susceptibility trait in inflammatory bowel disease (IBD), and early life stressors are reported to contribute to this disease susceptibility in adulthood. To identify disease mechanisms associated with early-life trauma that exacerbate IBD in adulthood, we used a "double-hit" neonatal inflammation (NI) and adult inflammation (AI) model that exhibits more severe mucosal injury in the colon later in life. In this study, we explore the underlying mechanisms of this aggravated injury. In rats exposed to both NI and AI, we found sustained increases in colonic permeability accompanied by significantly attenuated expression of the epithelial junction protein E-cadherin. Quantitative RT-PCR revealed a decreased Cdh1 (gene of E-cadherin) mRNA expression in NI + AI rats compared with NI or AI rats. Next, we performed microRNA microarrays to identify potential regulators of E-cadherin in NI + AI rats. We confirmed the overexpression of miR-155, a predicted regulator of E-cadherin, and selected it for further analysis based on reported significance in human IBD. Using ingenuity pathway analysis software, the targets and related canonical pathway of miR-155 were analyzed. Mechanistic studies identified histone hyperacetylation at the Mir155 promoter in NI + AI rats, concomitant with elevated RNA polymerase II binding. In vitro, E-cadherin knockdown markedly increased epithelial cell permeability, as did overexpression of miR-155 mimics, which significantly suppressed E-cadherin protein. In vivo, NI + AI colonic permeability was significantly reversed with administration of miR-155 inhibitor rectally. Our collective findings indicate that early-life inflammatory stressors trigger a significant and sustained epithelial injury by suppressing E-cadherin through epigenetic mechanisms.


Assuntos
Caderinas/genética , Colo/imunologia , Epigênese Genética/imunologia , Doenças Inflamatórias Intestinais/imunologia , Mucosa Intestinal/imunologia , MicroRNAs/metabolismo , Acetilação , Adulto , Animais , Caderinas/imunologia , Caderinas/metabolismo , Linhagem Celular , Colo/citologia , Colo/patologia , Modelos Animais de Doenças , Regulação para Baixo/imunologia , Células Epiteliais/citologia , Células Epiteliais/imunologia , Células Epiteliais/patologia , Técnicas de Silenciamento de Genes , Histonas/metabolismo , Humanos , Recém-Nascido , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/patologia , Junções Intercelulares/patologia , Mucosa Intestinal/citologia , Mucosa Intestinal/patologia , Masculino , MicroRNAs/antagonistas & inibidores , Permeabilidade/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Ratos
19.
J Immunol ; 204(4): 1047-1055, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31900340

RESUMO

Classical dendritic cells (cDC) can be classified into two major subsets: Irf8-dependent cDC1 and Irf4-expressing cDC2. Although these subsets play distinct roles in intestinal immune homeostasis, their functions in T cell-driven colitis remain unknown. To assess the role of IRF4 expression in cDC2 in T cell-driven colitis, CD11c-Cre.Irf4 fl/fl and Irf4 fl/fl mice were backcrossed onto a Rag-1 -/- background and used as recipients of CD45RBhiCD4+ T cells. Colitis score and innate immune cell influx were reduced in Cre+ mice 4 wk posttransfer, and these changes were associated with reduced CD4+ T cell counts in both the mesenteric lymph nodes and colon. By 7 wk, colitis score and colon CD4+ T cell numbers were similar in Cre+ and Cre- mice despite a selective reduction in Th17 cells in the colon of Cre+ mice and a continued reduction in CD4+ T cell numbers in mesenteric lymph nodes. Cotransfer of CD25+CD45RBlo CD4+ T cells prevented CD45RBhiCD4+ T cell-driven colitis in both Cre+ and Cre- recipients, demonstrating that IRF4 expression by cDC is not required for CD4+ regulatory T cell-mediated control of colitis. Collectively these results suggest a role for IRF4 expression in cDC2 in the generation of colitogenic CD4+ T cells, which becomes redundant as colitis progresses.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Colite/imunologia , Colo/imunologia , Células Dendríticas/imunologia , Fatores Reguladores de Interferon/metabolismo , Mucosa Intestinal/imunologia , Animais , Linfócitos T CD4-Positivos/transplante , Colite/patologia , Colo/patologia , Células Dendríticas/metabolismo , Modelos Animais de Doenças , Feminino , Proteínas de Homeodomínio/genética , Humanos , Fatores Reguladores de Interferon/genética , Mucosa Intestinal/patologia , Camundongos , Camundongos Knockout
20.
Mol Immunol ; 118: 191-200, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31896495

RESUMO

In our previous studies, we found that extracellular vesicles in mesenchymal stem cells can alleviate ulcerative colitis. In view of the fact that extracellular vesicles have the same immunomodulatory effects as their maternal cells and considering the important role of Th17 cells in the pathogenesis of ulcerative colitis, we aimed to investigate whether extracellular vesicles from mesenchymal stem cells can affect the differentiation of Th17 cells in ulcerative colitis. Histone H3K27me3 can regulate the expression of Th17 cell-related genes. We focused on determining whether the effect of extracellular vesicles on Th17 cells in ulcerative colitis is related to H3K27me3. For our experiments, we used low, medium and high doses of extracellular vesicles from mesenchymal stem cells to interfere with TNBS-induced colitis in rats and then evaluated the alleviation of inflammation and observed the impact of the extracellular vesicles on the differentiation of Th17 cells in ulcerative colitis. In addition, we detected the levels of histone H3K27me3 and the expression of its upstream methyltransferase and demethylase in the colon tissues of each group. Our data showed that extracellular vesicles from bone marrow mesenchymal stem cells can inhibit the abnormal differentiation of Th17 cells in ulcerative colitis, and the content of histone H3K27me3 was also changed accordingly. Our study suggests that extracellular vesicles from mesenchymal stem cells could inhibit the differentiation of Th17 cells in ulcerative colitis by regulating H3K27me3. This study reveals that H3K27me3 is an important target for inflammatory immune diseases associated with abnormal Th17 cell differentiation and indicates that mesenchymal stem cell extracellular vesicles are promising agents for the treatment of ulcerative colitis.


Assuntos
Diferenciação Celular/imunologia , Colite Ulcerativa/imunologia , Vesículas Extracelulares/imunologia , Histonas/imunologia , Células-Tronco Mesenquimais/imunologia , Células Th17/imunologia , Animais , Colo/imunologia , Modelos Animais de Doenças , Inflamação/imunologia , Masculino , Ratos , Ratos Sprague-Dawley
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