Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 2.363
Filtrar
1.
Int J Mol Sci ; 22(5)2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33806322

RESUMO

Coeliac disease (CD) is a clinically heterogeneous autoimmune disease with variable presentation and progression triggered by gluten intake. Molecular or genetic factors contribute to disease heterogeneity, but the reasons for different outcomes are poorly understood. Transcriptome studies of tissue biopsies from CD patients are scarce. Here, we present a high-resolution analysis of the transcriptomes extracted from duodenal biopsies of 24 children and adolescents with active CD and 21 individuals without CD but with intestinal afflictions as controls. The transcriptomes of CD patients divide into three groups-a mixed group presenting the control cases, and CD-low and CD-high groups referring to lower and higher levels of CD severity. Persistence of symptoms was weakly associated with subgroup, but the highest marsh stages were present in subgroup CD-high, together with the highest cell cycle rates as an indicator of virtually complete villous atrophy. Considerable variation in inflammation-level between subgroups was further deciphered into immune cell types using cell type de-convolution. Self-organizing maps portrayal was applied to provide high-resolution landscapes of the CD-transcriptome. We find asymmetric patterns of miRNA and long non-coding RNA and discuss the effect of epigenetic regulation. Expression of genes involved in interferon gamma signaling represent suitable markers to distinguish CD from non-CD cases. Multiple pathways overlay in CD biopsies in different ways, giving rise to heterogeneous transcriptional patterns, which potentially provide information about etiology and the course of the disease.


Assuntos
Doença Celíaca/genética , Adolescente , Estudos de Casos e Controles , Doença Celíaca/metabolismo , Doença Celíaca/patologia , Criança , Pré-Escolar , Epigênese Genética , Feminino , Perfilação da Expressão Gênica/estatística & dados numéricos , Marcadores Genéticos , Humanos , Lactente , Interferon gama/genética , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Intestino Delgado/imunologia , Intestino Delgado/metabolismo , Intestino Delgado/patologia , Aprendizado de Máquina , Masculino , RNA não Traduzido/genética , RNA não Traduzido/metabolismo , Índice de Gravidade de Doença , Transcriptoma
2.
Mol Med Rep ; 23(2)2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33655328

RESUMO

Immunoglobulin (Ig) A, an antibody with a pivotal role in gut homeostasis, can be modulated by stress and bovine lactoferrin (bLf). The aim of the present study was to analyze the impact of chronic stress on the IgA response in the small intestine during bLf treatment. Male BALB/c mice (n=6 mice/group) underwent 1 h of chronic stress by immobilization for 7 consecutive days or were left unstressed, and were untreated or treated with bLf (50, 500 or 5,000 µg). Plasma corticosterone expression levels were determined by ELISA. The distal small intestine was dissected to analyze: i) total IgA, secretory IgA and IgG, as well as and specific IgA and IgG antibody levels in the intestinal liquid by ELISA; ii) α­chain and polymeric immunoglobulin receptor (pIgR) protein expression in epithelial cell extracts analyzed by western blotting; iii) the mRNA expression levels of α­/J­chains, pIgR, IL­2, IL­4, IL­5 and IL­6 in whole mucosal samples by reverse transcription­quantitative PCR. Data were analyzed by one­way ANOVA, and the differences were analyzed by the Holm­Sidák post hoc test and were considered significant if P<0.05. Results from the present study revealed the upregulatory effects of chronic stress on the total antibody levels, protein (α­chain; 78­kDa pIgR) and mRNA (α­ and J­chains; pIgR; IL­6) expression levels were restricted by bLf under stress. The effects of chronic stress on the downregulation of IL­2 and IL­4 mRNA expression were not changed by bLf under stress. The corticosterone response in unstressed mice treated with 5,000 µg bLf and the specific­IgG levels in the unstressed and stressed groups treated with bLf at all doses were increased. The findings suggested an effect of bLf in maintaining homeostasis under stress.


Assuntos
Corticosterona/sangue , Intestino Delgado/metabolismo , Lactoferrina/farmacologia , Estresse Psicológico/tratamento farmacológico , Animais , Regulação da Expressão Gênica , Imunoglobulina A/análise , Imunoglobulina A/genética , Imunoglobulina A Secretora/análise , Imunoglobulina A Secretora/genética , Imunoglobulina G/análise , Imunoglobulina G/genética , Intestino Delgado/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estresse Psicológico/sangue , Estresse Psicológico/imunologia
3.
Nat Commun ; 12(1): 1093, 2021 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-33597537

RESUMO

Interactions between host and gut microbial communities are modulated by diets and play pivotal roles in immunological homeostasis and health. We show that exchanging the protein source in a high fat, high sugar, westernized diet from casein to whole-cell lysates of the non-commensal bacterium Methylococcus capsulatus Bath is sufficient to reverse western diet-induced changes in the gut microbiota to a state resembling that of lean, low fat diet-fed mice, both under mild thermal stress (T22 °C) and at thermoneutrality (T30 °C). Concomitant with microbiota changes, mice fed the Methylococcus-based western diet exhibit improved glucose regulation, reduced body and liver fat, and diminished hepatic immune infiltration. Intake of the Methylococcu-based diet markedly boosts Parabacteroides abundances in a manner depending on adaptive immunity, and upregulates triple positive (Foxp3+RORγt+IL-17+) regulatory T cells in the small and large intestine. Collectively, these data point to the potential for leveraging the use of McB lysates to improve immunometabolic homeostasis.


Assuntos
Intestino Grosso/imunologia , Intestino Delgado/imunologia , Methylococcus capsulatus/imunologia , Microbiota/imunologia , Proteínas/imunologia , Linfócitos T Reguladores/imunologia , Animais , Dieta , Fatores de Transcrição Forkhead/imunologia , Fatores de Transcrição Forkhead/metabolismo , Homeostase/imunologia , Interleucina-17/imunologia , Interleucina-17/metabolismo , Intestino Grosso/metabolismo , Intestino Grosso/microbiologia , Intestino Delgado/metabolismo , Intestino Delgado/microbiologia , Masculino , Methylococcus capsulatus/química , Camundongos Endogâmicos C57BL , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/imunologia , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Obesidade/imunologia , Proteínas/metabolismo , Linfócitos T Reguladores/metabolismo
4.
Int J Mol Sci ; 22(2)2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33435615

RESUMO

Celiac disease is an autoimmune disorder characterized by a heightened immune response to gluten proteins in the diet, leading to gastrointestinal symptoms and mucosal damage localized to the small intestine. Despite its prevalence, the only treatment currently available for celiac disease is complete avoidance of gluten proteins in the diet. Ongoing clinical trials have focused on targeting the immune response or gluten proteins through methods such as immunosuppression, enhanced protein degradation and protein sequestration. Recent studies suggest that polyphenols may elicit protective effects within the celiac disease milieu by disrupting the enzymatic hydrolysis of gluten proteins, sequestering gluten proteins from recognition by critical receptors in pathogenesis and exerting anti-inflammatory effects on the system as a whole. This review highlights mechanisms by which polyphenols can protect against celiac disease, takes a critical look at recent works and outlines future applications for this potential treatment method.


Assuntos
Doenças Autoimunes/imunologia , Doença Celíaca/imunologia , Gliadina/imunologia , Polifenóis/imunologia , Doenças Autoimunes/metabolismo , Doenças Autoimunes/prevenção & controle , Doença Celíaca/metabolismo , Doença Celíaca/prevenção & controle , Gliadina/metabolismo , Glutens/imunologia , Glutens/metabolismo , Humanos , Imunossupressão/métodos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/imunologia , Intestino Delgado/metabolismo , Polifenóis/metabolismo , Polifenóis/uso terapêutico , Estudos Prospectivos
6.
Int J Mol Sci ; 21(24)2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33353157

RESUMO

Acrylamide is one of the harmful substances present in food. The present study aimed to establish the effect of acrylamide supplementation in tolerable daily intake (TDI) dose (0.5 µg/kg b.w./day) and a dose ten times higher than TDI (5 µg/kg b.w./day) on the population of vasoactive intestinal peptide-like immunoreactive (VIP-LI) neurons in the porcine small intestine and the degree of the co-localization of VIP with other neuroactive substances (neuronal nitric oxide synthase (nNOS), substance P (SP), and cocaine- and amphetamine-regulated transcript peptide (CART)). In our work, 15 Danish landrace gilts (5 in each experimental group) received capsules (empty or with low or high doses of acrylamide) for a period of 28 days with their morning feeding. Using double immunofluorescence staining, we established that acrylamide supplementation increased the number of neurons showing immunoreactivity towards VIP in all types of enteric nervous system (ENS) plexuses and fragments of the small intestine studied. Moreover, both doses of acrylamide led to changes in the degree of co-localization of VIP with nNOS, SP, and CART in intramural neurons. The observed changes may be the adaptation of neurons to local inflammation, oxidative stress, or the direct toxic effects of acrylamide on intestinal neurons, also referred to as neuronal plasticity.


Assuntos
Acrilamida/farmacologia , Sistema Nervoso Entérico/citologia , Intestino Delgado/citologia , Neurônios/citologia , Peptídeo Intestinal Vasoativo/imunologia , Animais , Suplementos Nutricionais , Sistema Nervoso Entérico/efeitos dos fármacos , Sistema Nervoso Entérico/imunologia , Sistema Nervoso Entérico/metabolismo , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/imunologia , Intestino Delgado/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/imunologia , Neurônios/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Substância P/metabolismo , Suínos
7.
Front Immunol ; 11: 563414, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33329525

RESUMO

Since their discovery, innate lymphoid cells (ILCs) have gradually been gaining greater relevance in the field of immunology due to their multiple functions in the innate immune response. They can mainly be found in mucosal and barrier organs like skin, gut, and lungs, and have been classified into five main types (NKs, ILC1s, ILC2s, ILC3s, and Lti cells) according to their function and development. They all play major roles in functions such as tissue homeostasis, early pathogen defense, regulation of inflammation, or tissue remodeling. ILCs are mostly tissue-resident cells tightly bound to the tissue structure, a fact that requires long and complex protocols that do not always provide sufficient yield for analysis. This suggests the need for optimized approaches aimed at ensuring that enriched and viable ILC samples are obtained, in order to furnish quality results. Herein a detailed protocol is established for obtaining a single-cell suspension highly enriched in lymphoid cells from mouse gut in order to identify the different subsets of ILCs by means of flow cytometry. The cell marker panel and flow cytometry gating strategies for identification and quantification of all the different ILC populations are provided for simultaneous analysis. Moreover, the protocol described includes a procedure for studying the different cytokines produced by ILC3s involved in maintaining the integrity of the gut barrier and defending against extracellular pathogens. As a result, herein an efficient method is presented for studying mouse ILCs within the lamina propria of the small intestine and colon; this can constitute a useful tool for future investigations in the field.


Assuntos
Separação Celular/métodos , Colo/imunologia , Imunidade Inata , Mucosa Intestinal/citologia , Mucosa Intestinal/imunologia , Intestino Delgado/imunologia , Linfócitos/imunologia , Animais , Citocinas/metabolismo , Citometria de Fluxo , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos C57BL
8.
Am J Physiol Heart Circ Physiol ; 319(3): H705-H721, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32762560

RESUMO

Myeloperoxidase (MPO)-derived hypochlorous (HOCl) reacts with membrane plasmalogens to yield α-chlorofatty aldehydes such as 2-chlorofatty aldehyde (2-ClFALD) and its metabolite 2-chlorofatty acid (2-ClFA). Recent studies showed that 2-ClFALD and 2-ClFA serve as mediators of the inflammatory responses to sepsis by as yet unknown mechanisms. Since no scavenger for chlorinated lipids is available and on the basis of the well-established role of the MPO/HOCl/chlorinated lipid axis in inflammatory responses, we hypothesized that treatment with MPO inhibitors (N-acetyl lysyltyrosylcysteine amide or 4-aminobenzoic acid hydrazide) would inhibit inflammation and proinflammatory mediator expression induced by cecal ligation and puncture (CLP). We used intravital microscopy to quantify in vivo inflammatory responses in Sham and CLP rats with or without MPO inhibition. Small intestines, mesenteries, and lungs were collected to assess changes in MPO-positive staining and lung injury, respectively, as well as free 2-ClFA and proinflammatory mediators levels. CLP caused neutrophil infiltration, 2-ClFA generation, acute lung injury, leukocyte-/platelet-endothelium interactions, mast cell activation (MCA), plasminogen activator inhibitor-1 (PAI-1) production, and the expression of several cytokines, chemokines, and vascular endothelial growth factor, changes that were reduced by MPO inhibition. Pretreatment with a PAI-1 inhibitor or MC stabilizer prevented CLP-induced leukocyte-endothelium interactions and MCA, and abrogated exogenous 2-ClFALD-induced inflammatory responses. Thus, we provide evidence that MPO instigates these inflammatory changes in CLP and that chlorinated lipids may serve as a mechanistic link between the enzymatic activity of MPO and PAI-1- and mast cell-dependent adhesive interactions, providing a rationale for new therapeutic interventions in sepsis.NEW & NOTEWORTHY Using two distinct myeloperoxidase (MPO) inhibitors, we show for the first time that MPO plays an important role in producing increases in free 2-chlorofatty aldehyde (2-ClFALD)-a powerful proinflammatory chlorinated lipid in plasma and intestine-a number of cytokines and other inflammatory mediators, leukocyte and platelet rolling and adhesion in postcapillary venules, and lung injury in a cecal ligation and puncture model of sepsis. In addition, the use of a plasminogen activator inhibitor-1 (PAI-1) inhibitor or a mast cell stabilizer prevented inflammatory responses in CLP-induced sepsis. PAI-1 inhibition also prevented the proinflammatory responses to exogenous 2-ClFALD superfusion. Thus, our study provides some of the first evidence that MPO-derived free 2-ClFA plays an important role in CLP-induced sepsis by a PAI-1- and mast cell-dependent mechanism.


Assuntos
Ceco/microbiologia , Ácidos Graxos/metabolismo , Ácido Hipocloroso/metabolismo , Mediadores da Inflamação/metabolismo , Inflamação/enzimologia , Peroxidase/metabolismo , Sepse/enzimologia , Aldeídos/metabolismo , Animais , Anti-Inflamatórios/farmacologia , Ceco/cirurgia , Citocinas/metabolismo , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Inflamação/imunologia , Inflamação/microbiologia , Inflamação/prevenção & controle , Mediadores da Inflamação/antagonistas & inibidores , Intestino Delgado/enzimologia , Intestino Delgado/imunologia , Ligadura , Pulmão/enzimologia , Pulmão/imunologia , Mastócitos/enzimologia , Mastócitos/imunologia , Mesentério/enzimologia , Mesentério/imunologia , Peroxidase/antagonistas & inibidores , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Punções , Ratos Sprague-Dawley , Sepse/imunologia , Sepse/microbiologia , Sepse/prevenção & controle , Transdução de Sinais
9.
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
10.
Front Immunol ; 11: 1311, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32676080

RESUMO

Chimeric antigen receptor T cell (CART) therapy, administration of certain T cell-agonistic antibodies, immune check point inhibitors, coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) and Toxic shock syndrome (TSS) caused by streptococcal as well as staphylococcal superantigens share one common complication, that is T cell-driven cytokine release syndrome (CRS) accompanied by multiple organ dysfunction (MOD). It is not understood whether the failure of a particular organ contributes more significantly to the severity of CRS. Also not known is whether a specific cytokine or signaling pathway plays a more pathogenic role in precipitating MOD compared to others. As a result, there is no specific treatment available to date for CRS, and it is managed only symptomatically to support the deteriorating organ functions and maintain the blood pressure. Therefore, we used the superantigen-induced CRS model in HLA-DR3 transgenic mice, that closely mimics human CRS, to delineate the immunopathogenesis of CRS as well as to validate a novel treatment for CRS. Using this model, we demonstrate that (i) CRS is characterized by a rapid rise in systemic levels of several Th1/Th2/Th17/Th22 type cytokines within a few hours, followed by a quick decline. (ii) Even though multiple organs are affected, small intestinal immunopathology is the major contributor to mortality in CRS. (iii) IFN-γ deficiency significantly protected from lethal CRS by attenuating small bowel pathology, whereas IL-17A deficiency significantly increased mortality by augmenting small bowel pathology. (iv) RNA sequencing of small intestinal tissues indicated that IFN-γ-STAT1-driven inflammatory pathways combined with enhanced expression of pro-apoptotic molecules as well as extracellular matrix degradation contributed to small bowel pathology in CRS. These pathways were further enhanced by IL-17A deficiency and significantly down-regulated in mice lacking IFN-γ. (v) Ruxolitinib, a selective JAK-1/2 inhibitor, attenuated SAg-induced T cell activation, cytokine production, and small bowel pathology, thereby completely protecting from lethal CRS in both WT and IL-17A deficient HLA-DR3 mice. Overall, IFN-γ-JAK-STAT-driven pathways contribute to lethal small intestinal immunopathology in T cell-driven CRS.


Assuntos
Infecções por Coronavirus/patologia , Síndrome da Liberação de Citocina/tratamento farmacológico , Interferon gama/genética , Interleucina-17/genética , Inibidores de Janus Quinases/uso terapêutico , Pneumonia Viral/patologia , Pirazóis/uso terapêutico , Animais , Células Cultivadas , Infecções por Coronavirus/tratamento farmacológico , Síndrome da Liberação de Citocina/patologia , Síndrome da Liberação de Citocina/prevenção & controle , Citocinas/sangue , Citocinas/imunologia , Antígeno HLA-DR3/genética , Intestino Delgado/imunologia , Intestino Delgado/patologia , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Knockout , Pandemias , Pneumonia Viral/tratamento farmacológico , Linfócitos T Auxiliares-Indutores/imunologia
11.
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
12.
J Pediatr ; 223: 87-92.e1, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32381465

RESUMO

OBJECTIVE: To study the optimal cut-off value for anti-tissue transglutaminase type 2 IgA antibodies (TG2A) in serum to select for diagnostic small bowel biopsies for celiac disease in children with type 1 diabetes mellitus. STUDY DESIGN: Children with type 1 diabetes mellitus with elevated TG2A titers and duodenal biopsies performed during the course of their diabetes treatment were included. Anti-endomysial antibodies were recorded if present. The optimal TG2A cut-off value, expressed as the ratio between obtained value and upper limit of normal (ULN), was determined using receiver operating characteristic curve analysis and compared with the cut-off value used in the European Society for Pediatric Gastroenterology, Hepatology and Nutrition guidelines in terms of sensitivity, specificity, positive and negative predictive value. RESULTS: We included 63 children. The optimal cut-off value for performing biopsies is demonstrated to be 11 times the ULN. Raising the cut-off value from 3 times the ULN to 11 times the ULN changed sensitivity from 96% to 87% and increased specificity from 36% to 73%, increased the positive predictive value from 88% to 94% and lowered negative predictive value from 67% to 53%. The percentage of normal histology was decreased from 12% to 6%. CONCLUSIONS: Increasing the TG2A cut-off value for performing duodenal biopsies in children with type 1 diabetes mellitus and suspected celiac disease leads to a substantial reduction of unnecessary biopsies. We advocate to adapt the European Society for Pediatric Gastroenterology, Hepatology and Nutrition 2012 guidelines for this group of children, including monitoring patients with TG2A levels of less than 11 times the ULN over time.


Assuntos
Doença Celíaca/diagnóstico , Diabetes Mellitus Tipo 1/complicações , Proteínas de Ligação ao GTP/sangue , Transglutaminases/sangue , Adolescente , Anticorpos , Biópsia/efeitos adversos , Doença Celíaca/sangue , Doença Celíaca/etiologia , Criança , Pré-Escolar , Feminino , Humanos , Intestino Delgado/imunologia , Masculino , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade , Procedimentos Desnecessários
13.
Immunity ; 52(3): 528-541.e7, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32160525

RESUMO

Helminths, allergens, and certain protists induce type 2 immune responses, but the underlying mechanisms of immune activation remain poorly understood. In the small intestine, chemosensing by epithelial tuft cells results in the activation of group 2 innate lymphoid cells (ILC2s), which subsequently drive increased tuft cell frequency. This feedforward circuit is essential for intestinal remodeling and helminth clearance. ILC2 activation requires tuft-cell-derived interleukin-25 (IL-25), but whether additional signals regulate the circuit is unclear. Here, we show that tuft cells secrete cysteinyl leukotrienes (cysLTs) to rapidly activate type 2 immunity following chemosensing of helminth infection. CysLTs cooperate with IL-25 to activate ILC2s, and tuft-cell-specific ablation of leukotriene synthesis attenuates type 2 immunity and delays helminth clearance. Conversely, cysLTs are dispensable for the tuft cell response induced by intestinal protists. Our findings identify an additional tuft cell effector function and suggest context-specific regulation of tuft-ILC2 circuits within the small intestine.


Assuntos
Cisteína/imunologia , Mucosa Intestinal/imunologia , Intestino Delgado/imunologia , Leucotrienos/imunologia , Nippostrongylus/imunologia , Infecções por Strongylida/imunologia , Animais , Araquidonato 5-Lipoxigenase/genética , Araquidonato 5-Lipoxigenase/imunologia , Araquidonato 5-Lipoxigenase/metabolismo , Cisteína/metabolismo , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Células Epiteliais/parasitologia , Imunidade Inata/imunologia , Interleucina-17/genética , Interleucina-17/imunologia , Interleucina-17/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/parasitologia , Intestino Delgado/citologia , Intestino Delgado/metabolismo , Leucotrienos/metabolismo , Linfócitos/imunologia , Linfócitos/metabolismo , Linfócitos/parasitologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Nippostrongylus/fisiologia , Infecções por Strongylida/parasitologia
14.
Nat Immunol ; 21(4): 412-421, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32066954

RESUMO

Central memory T (TCM) cells patrol lymph nodes and perform conventional memory responses on restimulation: proliferation, migration and differentiation into diverse T cell subsets while also self-renewing. Resident memory T (TRM) cells are parked within single organs, share properties with terminal effectors and contribute to rapid host protection. We observed that reactivated TRM cells rejoined the circulating pool. Epigenetic analyses revealed that TRM cells align closely with conventional memory T cell populations, bearing little resemblance to recently activated effectors. Fully differentiated TRM cells isolated from small intestine epithelium exhibited the potential to differentiate into TCM cells, effector memory T cells and TRM cells on recall. Ex-TRM cells, former intestinal TRM cells that rejoined the circulating pool, heritably maintained a predilection for homing back to their tissue of origin on subsequent reactivation and a heightened capacity to redifferentiate into TRM cells. Thus, TRM cells can rejoin the circulation but are advantaged to re-form local TRM when called on.


Assuntos
Plasticidade Celular/imunologia , Memória Imunológica/imunologia , Subpopulações de Linfócitos T/imunologia , Animais , Diferenciação Celular/imunologia , Feminino , Mucosa Intestinal/imunologia , Intestino Delgado/imunologia , Camundongos , Camundongos Endogâmicos C57BL
15.
Nutrients ; 12(2)2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32069794

RESUMO

Dermatitis herpetiformis (DH), a cutaneous manifestation of coeliac disease, is characterized by transglutaminase (TG) 3-targeted dermal immunoglobulin A (IgA) deposits. The treatment for DH is the same as for coeliac disease, namely a life-long gluten-free diet. DH patients typically have gluten-dependent circulating autoantibodies targeting TG3 and TG2, and plasma cells secreting such autoantibodies have been detected in the small intestinal mucosa. This study investigates the gluten-responsiveness of intestinal TG3 and TG2 antibody-secreting plasma cells in 16 treated DH patients undergoing a gluten challenge. The frequency of both plasma cell populations increased significantly during the challenge, and their frequency correlated with the corresponding serum autoantibody levels at post-challenge. TG3-specific plasma cells were absent in all 18 untreated coeliac disease patients and seven non-coeliac control subjects on gluten-containing diets. These findings indicate that, in DH, both intestinal TG3- and TG2-antibody secreting plasma cells are gluten-dependent, and that TG3-antibody secreting plasma cells are DH-specific.


Assuntos
Autoanticorpos/sangue , Dermatite Herpetiforme/imunologia , Proteínas de Ligação ao GTP/imunologia , Glutens/efeitos adversos , Plasmócitos/imunologia , Transglutaminases/imunologia , Adulto , Idoso , Doença Celíaca/complicações , Doença Celíaca/imunologia , Dieta Livre de Glúten , Feminino , Glutens/imunologia , Humanos , Mucosa Intestinal/imunologia , Intestino Delgado/imunologia , Masculino , Pessoa de Meia-Idade
16.
Lab Anim (NY) ; 49(3): 79-88, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32042160

RESUMO

The intestinal immune system samples luminal contents to induce adaptive immune responses that include tolerance in the steady state and protective immunity during infection. How luminal substances are delivered to the immune system has not been fully investigated. Goblet cells have an important role in this process by delivering luminal substances to the immune system through the formation of goblet cell-associated antigen passages (GAPs). Soluble antigens in the intestinal lumen are transported across the epithelium transcellularly through GAPs and delivered to dendritic cells for presentation to T cells and induction of immune responses. GAPs can be identified and quantified by using the ability of GAP-forming goblet cells to take up fluorescently labeled dextran. Here, we describe a method to visualize GAPs and other cells that have the capacity to take up luminal substances by intraluminal injection of fluorescent dextran in mice under anesthesia, tissue sectioning for slide preparation and imaging with fluorescence microscopy. In contrast to in vivo two-photon imaging previously used to identify GAPs, this technique is not limited by anatomical constraints and can be used to visualize GAP formation throughout the length of the intestine. In addition, this method can be combined with common immunohistochemistry protocols to visualize other cell types. This approach can be used to compare GAP formation following different treatments or changes to the luminal environment and to uncover how sampling of luminal substances is altered in pathophysiological conditions. This protocol requires 8 working hours over 2-3 d to be completed.


Assuntos
Antígenos/metabolismo , Colo/imunologia , Células Dendríticas/imunologia , Células Caliciformes/imunologia , Vigilância Imunológica , Intestino Delgado/imunologia , Animais , Apresentação do Antígeno/efeitos dos fármacos , Antígenos/imunologia , Células Cultivadas , Células Dendríticas/efeitos dos fármacos , Dextranos/administração & dosagem , Corantes Fluorescentes/administração & dosagem , Células Caliciformes/efeitos dos fármacos , Mucosa Intestinal/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Microbiota/imunologia , Ovalbumina/administração & dosagem , Projetos de Pesquisa
17.
Immunohorizons ; 4(1): 23-32, 2020 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-31980480

RESUMO

Tuft cells are an epithelial cell type critical for initiating type 2 immune responses to parasites and protozoa in the small intestine. To respond to these stimuli, intestinal tuft cells use taste chemosensory signaling pathways, but the role of taste receptors in type 2 immunity is poorly understood. In this study, we show that the taste receptor TAS1R3, which detects sweet and umami in the tongue, also regulates tuft cell responses in the distal small intestine. BALB/c mice, which have an inactive form of TAS1R3, as well as Tas1r3-deficient C57BL6/J mice both have severely impaired responses to tuft cell-inducing signals in the ileum, including the protozoa Tritrichomonas muris and succinate. In contrast, TAS1R3 is not required to mount an immune response to the helminth Heligmosomoides polygyrus, which infects the proximal small intestine. Examination of uninfected Tas1r3-/- mice revealed a modest reduction in the number of tuft cells in the proximal small intestine but a severe decrease in the distal small intestine at homeostasis. Together, these results suggest that TAS1R3 influences intestinal immunity by shaping the epithelial cell landscape at steady-state.


Assuntos
Células Epiteliais/imunologia , Mucosa Intestinal/imunologia , Intestino Delgado/imunologia , Receptores Acoplados a Proteínas-G/imunologia , Receptores Acoplados a Proteínas-G/metabolismo , Animais , Células Epiteliais/metabolismo , Microbioma Gastrointestinal , Homeostase , Íleo/imunologia , Íleo/parasitologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/parasitologia , Intestino Delgado/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Nematospiroides dubius/imunologia , Receptores Acoplados a Proteínas-G/deficiência , Infecções por Strongylida/imunologia , Infecções por Strongylida/parasitologia , Paladar/fisiologia , Tritrichomonas/imunologia
18.
Sci Immunol ; 5(43)2020 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-31924686

RESUMO

A transitory, interleukin-25 (IL-25)-responsive, group 2 innate lymphoid cell (ILC2) subset induced during type 2 inflammation was recently identified as iILC2s. This study focuses on understanding the significance of this population in relation to tissue-resident nILC2s in the lung and intestine. RNA-sequencing and pathway analysis revealed the AP-1 superfamily transcription factor BATF (basic leucine zipper transcription factor, activating transcription factor-like) as a potential modulator of ILC2 cell fate. Infection of BATF-deficient mice with Nippostrongylus brasiliensis showed a selective defect in IL-25-mediated helminth clearance and a corresponding loss of iILC2s in the lung characterized as IL-17RBhigh, KLRG1high, BATFhigh, and Arg1low BATF deficiency selectively impaired iILC2s because it had no impact on tissue-resident nILC2 frequency or function. Pulmonary-associated iILC2s migrated to the lung after infection, where they represented an early source of IL-4 and IL-13. Although the composition of ILC2s in the small intestine was distinct from those in the lung, their frequency and IL-13 expression remained dependent on BATF, which was also required for optimal goblet and tuft cell hyperplasia. Findings support IL-25-responsive ILC2s as early sentinels of mucosal barrier integrity.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica/imunologia , Citocinas/imunologia , Linfócitos/imunologia , Nippostrongylus , Infecções por Strongylida/imunologia , Alérgenos/imunologia , Animais , Fatores de Transcrição de Zíper de Leucina Básica/genética , Feminino , Intestino Delgado/imunologia , Pulmão/imunologia , Masculino , Camundongos Transgênicos , Pyroglyphidae/imunologia
19.
Viruses ; 12(1)2020 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-31936476

RESUMO

Porcine deltacoronavirus (PDCoV) is a porcine enteropathogenic coronavirus that causes watery diarrhea, vomiting, and frequently death in piglets, causing serious economic losses to the pig industry. The strain CHN-JS-2017 was isolated and identified by cytopathology, immunofluorescence assays, transmission electron microscopy, and sequence analysis. A nucleotide sequence alignment showed that the whole genome of CHN-JS-2017 is 97.4%-99.6% identical to other PDCoV strains. The pathogenicity of the CHN-JS-2017 strain was investigated in orally inoculated five-day-old piglets; the piglets developed acute, watery diarrhea, but all recovered and survived. CHN-JS-2017 infection-induced microscopic lesions were observed, and viral antigens were detected mainly by immunohistochemical staining in the small intestine. The neonatal Fc receptor (FcRn) and polymeric immunoglobulin receptor (pIgR) are crucial immunoglobulin (Ig) receptors for the transcytosis ofimmunoglobulin G (IgG), IgA, or IgM. Importantly, CHN-JS-2017 infected five-day-old piglets could significantly down-regulate the expression of FcRn, pIgR, and nuclear factor-kappa B (NF-κB)in the intestinal mucosa. Note that the level of FcRn mRNA in the intestinal mucosa of normal piglets is positively correlated with pIgR and NF-κB. At the same time, the expressions of FcRn, pIgR, and NF-κB mRNA are also positively correlated in infected piglets. These results may help explain the immunological and pathological changes associated with porcine deltacorononirus infection.


Assuntos
Infecções por Coronavirus/veterinária , Coronavirus/classificação , Antígenos de Histocompatibilidade Classe I/imunologia , Mucosa Intestinal/imunologia , Receptores Fc/imunologia , Receptores de Imunoglobulina Polimérica/imunologia , Doenças dos Suínos/virologia , Animais , Antígenos Virais/análise , Coronavirus/isolamento & purificação , Infecções por Coronavirus/imunologia , Diarreia/veterinária , Diarreia/virologia , Regulação da Expressão Gênica , Mucosa Intestinal/virologia , Intestino Delgado/imunologia , Intestino Delgado/virologia , NF-kappa B/imunologia , Filogenia , RNA Viral/análise , Alinhamento de Sequência , Análise de Sequência de DNA , Suínos , Doenças dos Suínos/imunologia , Eliminação de Partículas Virais
20.
J Anim Sci ; 98(1)2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31944242

RESUMO

Mycotoxin deactivators are a widely used strategy to abrogate negative effects of mycotoxin-contaminated feed. It has not been adequately evaluated whether these deactivators may detoxify bacterial toxins in the intestinal lumen and subsequently lower the inflammatory response in chickens. The present objective was to study the effect of a multicomponent mycotoxin deactivator (B), containing a bentonite and a bacterial strain capable to enzymatically biotransform trichothecenes especially deoxynivalenol (DON), when supplemented to a DON-contaminated feed in combination with an oral lipopolysaccharide challenge on visceral organ size, expression of innate immune genes and mucosal permeability in the small intestine as well as on the cecal bacterial composition and metabolites in broiler chickens. Eighty 1-d-old male chickens were randomly allotted to four treatment groups in two replicate batches (n = 10/treatment/replicate): 1) basal diet without DON (CON), 2) CON diet supplemented with B (2.5 mg B/kg feed) (CON-B), 3) CON diet contaminated with 10 mg DON/kg feed (DON), and 4) DON diet supplemented with 2.5 mg B/kg feed (DON-B). In half of the chickens per treatment, effects were assessed under nonchallenge conditions, whereas in the other half of birds, to increase their intestinal bacterial toxin load, effects were tested after an oral challenge with 1 mg LPS/kg BW from Escherichia coli O55:B5 on the day before sampling. DON reduced (P < 0.05) the weight of bursa fabricii and thymus. DON increased the expression level of intestinal alkaline phosphatase at the duodenal mucosa (P = 0.027) but did not modify jejunal gene expression and mucosal permeability. The LPS challenge decreased the jejunal MUC2 expression but increased ZO1 and IL6 expression compared to the unchallenged animals (P < 0.05). DON × B interactions indicated lower expression of IL10 in duodenum and NFKB in jejunum with the B diet but higher expression with the DON-B diet (P = 0.050). Furthermore, the B lowered jejunal expression of NFKB and IL6 but only in LPS-challenged chickens (P < 0.05). Alterations in the cecal microbiota composition and VFA profile were likely associated with alterations in host physiology in the small intestine caused by DON, B, and LPS. According to the present data, B appeared to have potential to detoxify antigens other than DON in the intestinal lumen of chickens, whereby the toxin load may limit the efficacy of B to modify the intestinal and systemic response as indicated by interactions of DON, B, and LPS.


Assuntos
Galinhas/fisiologia , Suplementos Nutricionais/análise , Contaminação de Alimentos , Microbioma Gastrointestinal/efeitos dos fármacos , Micotoxinas/efeitos adversos , Tricotecenos/efeitos adversos , Ração Animal/análise , Animais , Ceco/microbiologia , Galinhas/imunologia , Galinhas/microbiologia , Dieta/veterinária , Mucosa Intestinal/microbiologia , Intestino Delgado/imunologia , Intestinos/imunologia , Jejuno/imunologia , Lipopolissacarídeos/administração & dosagem , Masculino , Tricotecenos/farmacologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...