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1.
Cell ; 175(5): 1307-1320.e22, 2018 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-30392957

RESUMEN

In the small intestine, a niche of accessory cell types supports the generation of mature epithelial cell types from intestinal stem cells (ISCs). It is unclear, however, if and how immune cells in the niche affect ISC fate or the balance between self-renewal and differentiation. Here, we use single-cell RNA sequencing (scRNA-seq) to identify MHC class II (MHCII) machinery enrichment in two subsets of Lgr5+ ISCs. We show that MHCII+ Lgr5+ ISCs are non-conventional antigen-presenting cells in co-cultures with CD4+ T helper (Th) cells. Stimulation of intestinal organoids with key Th cytokines affects Lgr5+ ISC renewal and differentiation in opposing ways: pro-inflammatory signals promote differentiation, while regulatory cells and cytokines reduce it. In vivo genetic perturbation of Th cells or MHCII expression on Lgr5+ ISCs impacts epithelial cell differentiation and IEC fate during infection. These interactions between Th cells and Lgr5+ ISCs, thus, orchestrate tissue-wide responses to external signals.


Asunto(s)
Diferenciación Celular , Autorrenovación de las Células , Interleucina-10/metabolismo , Células Madre/citología , Linfocitos T Colaboradores-Inductores/metabolismo , Animales , Diferenciación Celular/efectos de los fármacos , Autorrenovación de las Células/efectos de los fármacos , Citocinas/farmacología , Células Epiteliales/citología , Células Epiteliales/metabolismo , Femenino , Antígenos de Histocompatibilidad Clase II/metabolismo , Sistema Inmunológico/metabolismo , Intestinos/citología , Intestinos/microbiología , Masculino , Ratones , Ratones Endogámicos C57BL , Organoides/citología , Organoides/efectos de los fármacos , Organoides/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Salmonella enterica/patogenicidad , Células Madre/metabolismo , Linfocitos T Colaboradores-Inductores/citología
2.
Immunity ; 51(4): 696-708.e9, 2019 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-31618654

RESUMEN

Signaling abnormalities in immune responses in the small intestine can trigger chronic type 2 inflammation involving interaction of multiple immune cell types. To systematically characterize this response, we analyzed 58,067 immune cells from the mouse small intestine by single-cell RNA sequencing (scRNA-seq) at steady state and after induction of a type 2 inflammatory reaction to ovalbumin (OVA). Computational analysis revealed broad shifts in both cell-type composition and cell programs in response to the inflammation, especially in group 2 innate lymphoid cells (ILC2s). Inflammation induced the expression of exon 5 of Calca, which encodes the alpha-calcitonin gene-related peptide (α-CGRP), in intestinal KLRG1+ ILC2s. α-CGRP antagonized KLRG1+ ILC2s proliferation but promoted IL-5 expression. Genetic perturbation of α-CGRP increased the proportion of intestinal KLRG1+ ILC2s. Our work highlights a model where α-CGRP-mediated neuronal signaling is critical for suppressing ILC2 expansion and maintaining homeostasis of the type 2 immune machinery.


Asunto(s)
Péptido Relacionado con Gen de Calcitonina/metabolismo , Inflamación/inmunología , Intestinos/inmunología , Linfocitos/inmunología , Neuropéptidos/metabolismo , Animales , Péptido Relacionado con Gen de Calcitonina/genética , Células Cultivadas , Biología Computacional , Inmunidad Innata , Interleucina-5/genética , Interleucina-5/metabolismo , Lectinas Tipo C/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Transgénicos , Neuropéptidos/genética , Receptores Inmunológicos/metabolismo , Análisis de Secuencia de ARN , Transducción de Señal , Análisis de la Célula Individual , Células Th2/inmunología , Transcriptoma , Regulación hacia Arriba
3.
J Immunol ; 206(5): 963-977, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33495238

RESUMEN

Trichinella spiralis is recognized for its ability to regulate host immune responses via excretory/secretory (ES) products. Serine protease inhibitors (serpins) play an important role in ES product-mediated immunoregulatory effects during T. spiralis infection. In this study, the immunoregulatory properties of a serpin derived from T. spiralis (Ts-serpin) were explored in BALB/c mice. The results showed that naturally occurring Ts-serpin was detected in the stichosomes of muscle larvae and adult worms. Moreover, enhancing (by injection of a soluble-expressed recombinant Ts-serpin [rTs-serpin]) or blocking (by passive immunization with anti-rTs-serpin serum) the effects of Ts-serpin changed the levels of cytokines related to inflammation induced by T. spiralis infection in the serum, mesenteric lymph nodes, and peritoneal cavity, which then led to a change in the adult worm burden in early T. spiralis infection. Moreover, the phenotypic changes in peritoneal macrophages were found to be related to Ts-serpin-mediated immunoregulation. Furthermore, a STAT6 activation mechanism independent of IL-4Rα has been found to regulate protein-mediated alternative activation of bone marrow-derived macrophages and mimic the immunoregulatory role of Ts-serpin in T. spiralis infection. Finally, the anti-inflammatory properties of rTs-serpin and bone marrow-derived macrophage alternative activation by rTs-serpin were demonstrated using a trinitrobenzene sulfonic acid-induced inflammatory bowel disease model. In summary, a protein-triggered anti-inflammatory mechanism was found to favor the survival of T. spiralis in the early stage of infection and help to elucidate the immunoregulatory effects of T. spiralis on the host immune response.


Asunto(s)
Inmunidad/inmunología , Inflamación/inmunología , Intestinos/inmunología , Macrófagos/inmunología , Inhibidores de Serina Proteinasa/inmunología , Trichinella spiralis/inmunología , Triquinelosis/inmunología , Animales , Antígenos Helmínticos/inmunología , Citocinas/inmunología , Femenino , Inflamación/parasitología , Enfermedades Inflamatorias del Intestino/inmunología , Enfermedades Inflamatorias del Intestino/parasitología , Intestinos/parasitología , Macrófagos/parasitología , Ratones , Ratones Endogámicos BALB C , Triquinelosis/parasitología , Ácido Trinitrobencenosulfónico/inmunología
4.
Nature ; 551(7680): 333-339, 2017 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-29144463

RESUMEN

Intestinal epithelial cells absorb nutrients, respond to microbes, function as a barrier and help to coordinate immune responses. Here we report profiling of 53,193 individual epithelial cells from the small intestine and organoids of mice, which enabled the identification and characterization of previously unknown subtypes of intestinal epithelial cell and their gene signatures. We found unexpected diversity in hormone-secreting enteroendocrine cells and constructed the taxonomy of newly identified subtypes, and distinguished between two subtypes of tuft cell, one of which expresses the epithelial cytokine Tslp and the pan-immune marker CD45, which was not previously associated with non-haematopoietic cells. We also characterized the ways in which cell-intrinsic states and the proportions of different cell types respond to bacterial and helminth infections: Salmonella infection caused an increase in the abundance of Paneth cells and enterocytes, and broad activation of an antimicrobial program; Heligmosomoides polygyrus caused an increase in the abundance of goblet and tuft cells. Our survey highlights previously unidentified markers and programs, associates sensory molecules with cell types, and uncovers principles of gut homeostasis and response to pathogens.


Asunto(s)
Células Epiteliales/citología , Epitelio/metabolismo , Intestino Delgado/citología , Análisis de la Célula Individual , Animales , Diferenciación Celular , Citocinas/metabolismo , Enterocitos/metabolismo , Células Epiteliales/metabolismo , Femenino , Perfilación de la Expresión Génica , Homeostasis , Antígenos Comunes de Leucocito/metabolismo , Masculino , Ratones , Organoides/citología , Organoides/metabolismo , Células de Paneth/metabolismo , Transcripción Genética , Linfopoyetina del Estroma Tímico
5.
Parasitology ; 144(6): 712-719, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28069101

RESUMEN

Trichinella spiralis is a parasitic helminth that can infect almost all mammals, including humans. Trichinella spiralis infection elicits a typical type 2 immune responses, while suppresses type 1 immune responses, which is in favour of their parasitism. DNA vaccines have been shown to be capable of eliciting balanced CD4+ and CD8+ T cell responses as well as humoral immune responses in small-animal models, which will be advantage to induce protective immune response against helminth infection. In this study, serine protease (Ts-NBLsp) was encoded by a cDNA fragment of new-born T. spiralis larvae, and was inserted after CMV promoter to construct a DNA vaccine [pcDNA3·1(+)-Ts-NBLsp]. Ts-NBLsp expression was demonstrated by immunofluorescence. Sera samples were obtained from vaccinated mice, and they showed strong anti-Ts-NBLsp-specific IgG response. Mice immunized with the pcDNA3·1(+)-Ts-NBLsp DNA vaccine showed a 77·93% reduction in muscle larvae (ML) following challenge with T. spiralis ML. Our results demonstrate that the vaccination with pcDNA3·1(+)-Ts-NBLsp plasmid promoted the balance of type 1 and 2 immune responses and produced a significant protection against T. spiralis infection in mice.


Asunto(s)
Proteínas del Helminto/inmunología , Trichinella spiralis/inmunología , Triquinelosis/prevención & control , Vacunas de ADN , Animales , Anticuerpos Antihelmínticos/biosíntesis , Anticuerpos Antihelmínticos/sangre , Relación CD4-CD8 , Citocinas/biosíntesis , Citocinas/sangre , Femenino , Proteínas del Helminto/genética , Inmunoglobulina G/biosíntesis , Inmunoglobulina G/sangre , Larva/inmunología , Ratones , Plásmidos/genética , Plásmidos/metabolismo , Ratas , Ratas Wistar , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Serina Proteasas/genética , Serina Proteasas/inmunología , Linfocitos T/citología , Triquinelosis/inmunología , Vacunas de ADN/inmunología
6.
Am J Physiol Gastrointest Liver Physiol ; 311(4): G744-G753, 2016 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-27562058

RESUMEN

The therapeutic and preventive application of probiotics for necrotizing enterocolitis (NEC) has been supported by more and more experimental and clinical evidence in which Toll-like receptor 4 (TLR-4) exerts a significant role. In immune cells, probiotics not only regulate the expression of TLR-4 but also use the TLR-4 to modulate the immune response. Probiotics may also use the TLR-4 in immature enterocytes for anti-inflammation. Here we demonstrate that probiotic conditioned media (PCM) from Bifidobacterium longum supp infantis but not isolated organisms attenuates interleukin-6 (IL-6) induction in response to IL-1ß by using TLR-4 in a human fetal small intestinal epithelial cell line (H4 cells), human fetal small intestinal xenografts, mouse fetal small intestinal organ culture tissues, and primary NEC enterocytes. Furthermore, we show that PCM, using TLR-4, downregulates the mRNA expression of interleukin-1 receptor-associated kinase 2 (IRAK-2), a common adapter protein shared by IL-1ß and TLR-4 signaling. PCM also reduces the phosphorylation of the activator-protein 1 (AP-1) transcription factors c-Jun and c-Fos in response to IL-1ß stimulation in a TLR-4-dependent manner. This study suggests that PCM may use TLR-4 through IRAK-2 and via AP-1 to prevent IL-1ß-induced IL-6 induction in immature enterocytes. Based on these observations, the combined use of probiotics and anti-TLR-4 therapy to prevent NEC may not be a good strategy.


Asunto(s)
Bifidobacterium longum subspecies infantis , Medios de Cultivo Condicionados/farmacología , Enterocolitis Necrotizante/prevención & control , Enterocitos/metabolismo , Receptor Toll-Like 4/metabolismo , Animales , Línea Celular , Enterocolitis Necrotizante/metabolismo , Enterocitos/efectos de los fármacos , Humanos , Interleucina-1beta/farmacología , Interleucina-6/metabolismo , Intestino Delgado/efectos de los fármacos , Intestino Delgado/metabolismo , Ratones , Transducción de Señal/efectos de los fármacos
7.
J Immunol ; 193(3): 1398-407, 2014 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-24973448

RESUMEN

States of chronic inflammation such as inflammatory bowel disease are often associated with dysregulated iron metabolism and the consequent development of an anemia that is caused by maldistribution of iron. Abnormally elevated expression of the hormone hepcidin, the central regulator of systemic iron homeostasis, has been implicated in these abnormalities. However, the mechanisms that regulate hepcidin expression in conditions such as inflammatory bowel disease are not completely understood. To clarify this issue, we studied hepcidin expression in mouse models of colitis. We found that dextran sulfate sodium-induced colitis inhibited hepcidin expression in wild-type mice but upregulated it in IL-10-deficient animals. We identified two mechanisms contributing to this difference. Firstly, erythropoietic activity, as indicated by serum erythropoietin concentrations and splenic erythropoiesis, was higher in the wild-type mice, and pharmacologic inhibition of erythropoiesis prevented colitis-associated hepcidin downregulation in these animals. Secondly, the IL-10 knockout mice had higher expression of multiple inflammatory genes in the liver, including several controlled by STAT3, a key regulator of hepcidin. The results of cohousing and fecal transplantation experiments indicated that the microbiota was involved in modulating the expression of hepcidin and other STAT3-dependent hepatic genes in the context of intestinal inflammation. Our observations thus demonstrate the importance of erythropoietic activity and the microbiota in influencing hepcidin expression during colitis and provide insight into the dysregulated iron homeostasis seen in inflammatory diseases.


Asunto(s)
Eritropoyesis/inmunología , Eritropoyetina/metabolismo , Hepcidinas/genética , Mediadores de Inflamación/sangre , Enfermedades Inflamatorias del Intestino/microbiología , Mucosa Intestinal/inmunología , Hierro/fisiología , Microbiota/inmunología , Animales , Bacteroides fragilis/inmunología , Colitis/inducido químicamente , Colitis/genética , Colitis/inmunología , Sulfato de Dextran/administración & dosificación , Modelos Animales de Enfermedad , Eritropoyesis/genética , Eritropoyetina/sangre , Femenino , Hepcidinas/biosíntesis , Homeostasis/inmunología , Enfermedades Inflamatorias del Intestino/inmunología , Enfermedades Inflamatorias del Intestino/patología , Interleucina-10/deficiencia , Interleucina-10/genética , Mucosa Intestinal/microbiología , Mucosa Intestinal/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Factor de Transcripción STAT3/fisiología , Streptococcaceae/inmunología
8.
Pediatr Res ; 77(3): 416-24, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25521917

RESUMEN

BACKGROUND: Necrotizing enterocolitis (NEC) is an immature intestinal condition resulting in devastating intestinal inflammation due to unknown mechanisms. Evidence has suggested that intestinal maturation attenuates the severity of NEC and Toll-like receptor 4 (TLR4) has been suggested to play a critical role in its pathogenesis. We investigated whether maturational effects of TLR4 expression in immature colon might contribute to the development of NEC. METHODS: TLR4 colonocyte expression was detected by immunofluorescence confocal microscopy. Interleukin-6 (IL-6) levels were assayed by an enzyme-linked immunosorbent assay (ELISA). RESULTS: TLR4 expression was high in fetal colonic epithelium in human and mouse, with earlier gestation having a higher surface/cytoplasm distribution. TLR4 remained high in mouse postnatal day 1 but the surface/cytoplasm distribution was reduced. TLR4 decreased in amount and then was expressed in crypts in the mature human and mouse colon. Hydrocortisone (HC) reduced the surface/cytoplasm distribution of TLR4 in human fetal colon. Elevated IL-6 levels in immature colon after lipopolysaccharide were attenuated by HC in human and mouse. CONCLUSION: Expression, localization, and signaling of TLR4 in colonic epithelium may be developmentally regulated. HC may accelerate the TLR developmental pathway change to an adult type, which may account for its impact on TLR4 signaling.


Asunto(s)
Colon/citología , Enterocolitis Necrotizante/genética , Células Epiteliales/fisiología , Regulación del Desarrollo de la Expresión Génica/fisiología , Hidrocortisona/farmacología , Receptor Toll-Like 4/metabolismo , Animales , Ensayo de Inmunoadsorción Enzimática , Células Epiteliales/metabolismo , Humanos , Hidrocortisona/administración & dosificación , Inyecciones Subcutáneas , Interleucina-6/metabolismo , Ratones , Ratones Endogámicos C57BL , Microscopía Fluorescente
9.
Exp Parasitol ; 159: 264-73, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26545353

RESUMEN

Trichinella spiralis Nudix hydrolase (TsNd) was identified by screening a T7 phage display cDNA library from T. spiralis intestinal infective larvae (IIL), and vaccination of mice with recombinant TsNd protein (rTsNd) or TsNd DNA vaccine produced a partial protective immunity. The aim of this study was to identify the characteristics and biological functions of TsNd in the process of invasion and development of T. spiralis larvae. Transcription and expression of TsNd gene at all developmental stages of T. spiralis were observed by qPCR and immunofluorescent test (IFT). The rTsNd had the Nd enzymatic activity to dGTP, NAD, NADP and CoA. Its kinetic properties on the preferred substrate dGTP were calculated, and the Vmax, Km, and kcat/Km values at pH 8.0 were 3.19 µM min(-1) µg(-1), 370 µM, and 144 s(-1) M(-1), respectively, in reaction matrix containing 5 mM Zn(2+) and 2 mM DTT. The rTsNd was active from 25 °C to 50 °C, with optimal activity at 37 °C. rTsNd was able to bind specifically to mouse intestinal epithelial cells (IECs) and promoted the larval invasion of IECs, whereas anti-rTsNd antibodies inhibited the larval invasion of IECs in a dose-dependent manner. Anti-rTsNd antibodies could kill T. spiralis infective larvae by an ADCC-mediated mechanism. Our results showed that the rTsNd protein was able to interact with host IECs, had the Nudix hydrolasing activity and the enzymatic activity appeared to be essential indispensable for the T. spiralis larval invasion, development and survival in host.


Asunto(s)
Hidrolasas/metabolismo , Trichinella spiralis/enzimología , Animales , Anticuerpos Antihelmínticos/inmunología , Citotoxicidad Celular Dependiente de Anticuerpos , Western Blotting , Relación Dosis-Respuesta Inmunológica , Femenino , Técnica del Anticuerpo Fluorescente , Regulación Enzimológica de la Expresión Génica , Guanosina Trifosfato/metabolismo , Hidrolasas/genética , Hidrolasas/inmunología , Hidrólisis , Mucosa Intestinal/citología , Mucosa Intestinal/parasitología , Estadios del Ciclo de Vida/genética , Masculino , Ratones , Ratones Endogámicos BALB C , Microscopía Confocal , Sus scrofa , Porcinos , Transcripción Genética , Trichinella spiralis/genética , Trichinella spiralis/crecimiento & desarrollo , Trichinella spiralis/inmunología , Triquinelosis/parasitología
10.
Infect Immun ; 82(9): 3855-66, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24980971

RESUMEN

Salmonella enterica serovar Typhimurium is a Gram-negative food-borne pathogen that is a major cause of acute gastroenteritis in humans. The ability of the host to control such bacterial pathogens may be influenced by host immune status and by concurrent infections. Helminth parasites are of particular interest in this context because of their ability to modulate host immune responses and because their geographic distribution coincides with those parts of the world where infectious gastroenteritis is most problematic. To test the hypothesis that helminth infection may negatively regulate host mucosal innate immunity against bacterial enteropathogens, a murine coinfection model was established by using the intestinal nematode Heligmosomoides polygyrus and S. Typhimurium. We found that mice coinfected with S. Typhimurium and H. polygyrus developed more severe intestinal inflammation than animals infected with S. Typhimurium alone. The enhanced susceptibility to Salmonella-induced intestinal injury in coinfected mice was found to be associated with diminished neutrophil recruitment to the site of bacterial infection that correlated with decreased expression of the chemoattractants CXCL2/macrophage inflammatory protein 2 (MIP-2) and CXCL1/keratinocyte-derived chemokine (KC), poor control of bacterial replication, and exacerbated intestinal inflammation. The mechanism of helminth-induced inhibition of MIP-2 and KC expression involved interleukin-10 (IL-10) and, to a lesser extent, IL-4 and IL-13. Ly6G antibody-mediated depletion of neutrophils reproduced the adverse effects of H. polygyrus on Salmonella infection. Our results suggest that impaired neutrophil recruitment is an important contributor to the enhanced severity of Salmonella enterocolitis associated with helminth coinfection.


Asunto(s)
Coinfección/inmunología , Inmunidad Innata/inmunología , Inflamación/inmunología , Mucosa Intestinal/inmunología , Salmonelosis Animal/inmunología , Salmonella typhimurium/inmunología , Animales , Quimiocina CXCL1/inmunología , Quimiocina CXCL2/inmunología , Coinfección/microbiología , Modelos Animales de Enfermedad , Femenino , Inflamación/microbiología , Interleucinas/inmunología , Mucosa Intestinal/microbiología , Ratones , Ratones Endogámicos C57BL , Nematospiroides dubius/inmunología , Neutrófilos/inmunología , Neutrófilos/microbiología , Salmonelosis Animal/microbiología , Infecciones por Strongylida/inmunología , Infecciones por Strongylida/microbiología
11.
Am J Physiol Gastrointest Liver Physiol ; 306(9): G779-87, 2014 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-24627567

RESUMEN

Necrotizing enterocolitis (NEC) is associated with a high morbidity and mortality in very low birth weight infants. Several hypotheses regarding the pathogenesis of NEC have been proposed but to date no effective treatment is available. Previous studies suggest that probiotic supplementation is protective. We recently reported that probiotic (Bifidobacterium infantis) conditioned medium (PCM) has an anti-inflammatory effect in cultured fetal human intestinal cells (H4) and fetal intestine explants. In this study, we tested in vivo whether PCM protects neonatal mice from developing intestinal inflammation induced by exposure to Cronobacter sakazakii (C. sakazakii), an opportunistic pathogen associated with NEC. We found that infected neonatal mice had a significantly lower body weight than control groups. Infection led to ileal tissue damage including villous rupture, disruption of epithelial cell alignment, intestinal inflammation, apoptotic cell loss, and decreased mucus production. Pretreatment with PCM prevented infection caused decrease in body weight, attenuated enterocyte apoptotic cell death, mitigated reduced mucin production, and maintained ileal structure. Infected ileum expressed reduced levels of IκBα, which could be restored upon pretreatment with PCM. We also observed a nuclear translocation of NF-κB p65 in H4 cells exposed to C. sakazakii, which was prevented in PCM-pretreated cells. Finally, treatment of neonatal mice with PCM prior to infection sustained the capacity of ileal epithelial proliferation. This study suggests that an active component(s) released into the culture medium by B. infantis may prevent ileal damage by a pathogen linked to NEC.


Asunto(s)
Bifidobacterium/metabolismo , Cronobacter sakazakii/patogenicidad , Medios de Cultivo Condicionados/farmacología , Infecciones por Enterobacteriaceae/prevención & control , Enterocolitis Necrotizante/prevención & control , Ileítis/prevención & control , Íleon/microbiología , Probióticos/farmacología , Transporte Activo de Núcleo Celular , Animales , Animales Recién Nacidos , Apoptosis , Bifidobacterium/clasificación , Peso Corporal , Línea Celular , Proliferación Celular , Modelos Animales de Enfermedad , Infecciones por Enterobacteriaceae/metabolismo , Infecciones por Enterobacteriaceae/microbiología , Infecciones por Enterobacteriaceae/patología , Enterocolitis Necrotizante/metabolismo , Enterocolitis Necrotizante/microbiología , Enterocolitis Necrotizante/patología , Enterocitos/microbiología , Enterocitos/patología , Humanos , Proteínas I-kappa B/metabolismo , Ileítis/metabolismo , Ileítis/microbiología , Ileítis/patología , Íleon/metabolismo , Íleon/patología , Ratones , Ratones Endogámicos C57BL , Mucinas/metabolismo , Inhibidor NF-kappaB alfa , Factor de Transcripción ReIA/metabolismo
12.
Gastroenterology ; 145(3): 591-601.e3, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23732773

RESUMEN

BACKGROUND & AIMS: Caspase recruitment domain 9 (CARD9) is an adaptor protein that integrates signals downstream of pattern recognition receptors. CARD9 has been associated with autoinflammatory disorders, and loss-of-function mutations have been associated with chronic mucocutaneous candidiasis, but the role of CARD9 in intestinal inflammation is unknown. We characterized the role of Card9 in mucosal immune responses to intestinal epithelial injury and infection. METHODS: We induced intestinal inflammation in Card9-null mice by administration of dextran sulfate sodium (DSS) or Citrobacter rodentium. We analyzed body weight, assessed inflammation by histology, and measured levels of cytokines and chemokines using quantitative reverse-transcription polymerase chain reaction and enzyme-linked immunosorbent assay. Cell populations were compared between wild-type and Card9-null mice by flow cytometry analysis. RESULTS: Colon tissues and mesenteric lymph nodes of Card9-null mice had reduced levels of interleukin (IL)-6, interferon-γ, and T-helper (Th)17 cytokines after administration of DSS, compared with wild-type mice. IL-17A and IL-22 expression were reduced in the recovery phase after DSS administration, coincident with decreased expression of antimicrobial peptides and the chemokine (C-C motif) ligand 20 (Ccl20). Although Card9-null mice had more intestinal fungi based on 18S analysis, their Th17 responses remained defective even when an antifungal agent was administered throughout DSS exposure. Moreover, Card9-null mice had impaired immune responses to C rodentium, characterized by decreased levels of colonic IL-6, IL-17A, IL-22, and regenerating islet-derived 3 gamma (RegIIIγ), as well as fewer IL-22-producing innate lymphoid cells (ILCs) in colon lamina propria. CONCLUSIONS: The adaptor protein CARD9 coordinates Th17- and innate lymphoid cell-mediated intestinal immune responses after epithelial injury in mice.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Citrobacter rodentium , Colitis/metabolismo , Infecciones por Enterobacteriaceae/metabolismo , Mucosa Intestinal/metabolismo , Células Th17/metabolismo , Animales , Biomarcadores/metabolismo , Proteínas Adaptadoras de Señalización CARD , Colitis/etiología , Colitis/inmunología , Colitis/patología , Citocinas/metabolismo , Sulfato de Dextran , Infecciones por Enterobacteriaceae/inmunología , Infecciones por Enterobacteriaceae/patología , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Inmunidad Innata , Mucosa Intestinal/inmunología , Mucosa Intestinal/microbiología , Mucosa Intestinal/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
13.
Gastroenterology ; 145(6): 1347-57, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23973919

RESUMEN

BACKGROUND & AIMS: Intestinal epithelial cells aid in mucosal defense by providing a physical barrier against entry of pathogenic bacteria and secreting antimicrobial peptides (AMPs). Autophagy is an important component of immune homeostasis. However, little is known about its role in specific cell types during bacterial infection in vivo. We investigated the role of autophagy in the response of intestinal epithelial and antigen-presenting cells to Salmonella infection in mice. METHODS: We generated mice deficient in Atg16l1 in epithelial cells (Atg16l1(f/f) × Villin-cre) or CD11c(+) cells (Atg16l1(f/f) × CD11c-cre); these mice were used to assess cell type-specific antibacterial autophagy. All responses were compared with Atg16l1(f/f) mice (controls). Mice were infected with Salmonella enterica serovar typhimurium; cecum and small-intestine tissues were collected for immunofluorescence, histology, and quantitative reverse-transcription polymerase chain reaction analyses of cytokines and AMPs. Modulators of autophagy were screened to evaluate their effects on antibacterial responses in human epithelial cells. RESULTS: Autophagy was induced in small intestine and cecum after infection with S typhimurium, and required Atg16l1. S typhimurium colocalized with microtubule-associated protein 1 light chain 3ß (Map1lc3b or LC3) in the intestinal epithelium of control mice but not in Atg16l1(f/f) × Villin-cre mice. Atg16l1(f/f) × Villin-cre mice also had fewer Paneth cells and abnormal granule morphology, leading to reduced expression of AMPs. Consistent with these defective immune responses, Atg16l1(f/f) × Villin-cre mice had increased inflammation and systemic translocation of bacteria compared with control mice. In contrast, we observed few differences between Atg16l1(f/f) × CD11c-cre and control mice. Trifluoperazine promoted autophagy and bacterial clearance in HeLa cells; these effects were reduced upon knockdown of ATG16L1. CONCLUSIONS: Atg16l1 regulates autophagy in intestinal epithelial cells and is required for bacterial clearance. It also is required to prevent systemic infection of mice with enteric bacteria.


Asunto(s)
Autofagia/fisiología , Proteínas Portadoras/fisiología , Mucosa Intestinal/fisiología , Salmonelosis Animal/prevención & control , Animales , Proteínas Relacionadas con la Autofagia , Antígeno CD11c/fisiología , Proteínas Portadoras/genética , Modelos Animales de Enfermedad , Células HeLa , Humanos , Mucosa Intestinal/microbiología , Mucosa Intestinal/patología , Ratones , Ratones Noqueados , Proteínas de Microfilamentos/fisiología , Proteínas Asociadas a Microtúbulos/fisiología , Salmonelosis Animal/patología , Salmonelosis Animal/fisiopatología , Salmonella typhimurium/aislamiento & purificación
14.
J Immunol ; 189(3): 1459-66, 2012 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-22732589

RESUMEN

Autophagy is an important mechanism used by macrophages to kill intracellular pathogens. The results reported in this study demonstrate that autophagy is also involved in the macrophage killing of the extracellular enteropathogen Citrobacter rodentium after phagocytosis. The process was significantly impaired in macrophages isolated from mice chronically infected with the helminth parasite Heligmosomoides polygyrus. The H. polygyrus-mediated inhibition of autophagy was Th2 dependent because it was not observed in macrophages isolated from helminth-infected STAT6-deficient mice. Moreover, autophagy of Citrobacter was inhibited by treating macrophages with IL-4 and IL-13. The effect of H. polygyrus on autophagy was associated with decreased expression and processing of L chain protein 3 (LC3), a key component of the autophagic machinery. The helminth-induced inhibition of LC3 expression and processing was STAT6 dependent and could be recapitulated by treatment of macrophages with IL-4 and IL-13. Knockdown of LC3 significantly inhibited autophagic killing of Citrobacter, attesting to the functional importance of the H. polygyrus-mediated downregulation of this process. These observations reveal a new aspect of the immunosuppressive effects of helminth infection and provide mechanistic insights into our earlier finding that H. polygyrus significantly worsens the in vivo course of Citrobacter infection.


Asunto(s)
Autofagia/inmunología , Citrobacter rodentium/inmunología , Infecciones por Enterobacteriaceae/inmunología , Macrófagos Peritoneales/inmunología , Nematospiroides dubius/inmunología , Infecciones por Strongylida/inmunología , Animales , Citrobacter rodentium/crecimiento & desarrollo , Citrobacter rodentium/patogenicidad , Regulación hacia Abajo/inmunología , Infecciones por Enterobacteriaceae/parasitología , Infecciones por Enterobacteriaceae/patología , Femenino , Macrófagos Peritoneales/microbiología , Macrófagos Peritoneales/parasitología , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Proteínas Asociadas a Microtúbulos/antagonistas & inhibidores , Proteínas Asociadas a Microtúbulos/biosíntesis , Proteínas Asociadas a Microtúbulos/genética , Nematospiroides dubius/crecimiento & desarrollo , Nematospiroides dubius/patogenicidad , Procesamiento Proteico-Postraduccional/inmunología , Infecciones por Strongylida/microbiología , Infecciones por Strongylida/patología
15.
Gastroenterology ; 142(4): 865-874.e2, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22202458

RESUMEN

BACKGROUND & AIMS: T helper (Th) 17 cells produce the effector cytokine interleukin (IL)-17, along with IL-22, which stimulates colonic epithelial cells to produce a membrane-bound mucin, Muc1. Muc1 is a component of the colonic mucus, which functions as a lubricant and a physiologic barrier between luminal contents and mucosal surface. The gene MUC1 has been associated with susceptibility to inflammatory bowel disease; we investigated the role of Muc1 in development of colitis in mice. METHODS: Muc1 and RAG1 were disrupted in mice (Muc/RAG double knockout mice); Th1-mediated colitis was induced by intravenous injection of CD4(+)CD45RB(high) T cells. We also studied Th2-mediated colitis using mice with disruptions in Muc1 and T-cell receptor α chain (Muc/TCR double knockout mice). RESULTS: Muc1 deficiency led to the development of more severe forms of Th1- and Th2-induced colitis than controls. Loss of Muc1 increased colonic permeability and the Th17-cell, but not Th2 or Th1 cell, response in the inflamed colon. Loss of Muc1 also promoted expansion of an innate lymphoid cell population (Lin(-) ckit(-) Thy1(+) Sca1(+)) that produces IL-17. The expansion of Th17 adaptive immune cells and innate lymphoid cells required the commensal microbiota. CONCLUSIONS: Muc1, which is up-regulated by Th17 signaling, functions in a negative feedback pathway that prevents an excessive Th17 cell response in inflamed colons of mice. Disruption of this negative feedback pathway, perhaps by variants in Muc1, might contribute to inflammatory bowel disease in patients.


Asunto(s)
Colitis/metabolismo , Colon/metabolismo , Mucosa Intestinal/metabolismo , Mucina-1/metabolismo , Células Th17/metabolismo , Inmunidad Adaptativa , Animales , Células Cultivadas , Técnicas de Cocultivo , Colitis/genética , Colitis/inmunología , Colitis/microbiología , Colitis/patología , Colitis/prevención & control , Colon/inmunología , Colon/microbiología , Colon/patología , Modelos Animales de Enfermedad , Retroalimentación Fisiológica , Genes Codificadores de la Cadena alfa de los Receptores de Linfocito T , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Inmunidad Innata , Mediadores de Inflamación/metabolismo , Mucosa Intestinal/inmunología , Mucosa Intestinal/microbiología , Mucosa Intestinal/patología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Mucina-1/genética , Permeabilidad , Transducción de Señal , Células TH1/inmunología , Células TH1/metabolismo , Células TH1/trasplante , Células Th17/inmunología , Células Th2/inmunología , Células Th2/metabolismo
16.
Ann Neurol ; 71(5): 687-98, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22368036

RESUMEN

OBJECTIVE: There are approximately 8.5 million Alzheimer disease (AD) patients who need anesthesia and surgery care every year. The inhalation anesthetic isoflurane, but not desflurane, has been shown to induce caspase activation and apoptosis, which are part of AD neuropathogenesis, through the mitochondria-dependent apoptosis pathway. However, the in vivo relevance, underlying mechanisms, and functional consequences of these findings remain largely to be determined. METHODS: We therefore set out to assess the effects of isoflurane and desflurane on mitochondrial function, cytotoxicity, learning, and memory using flow cytometry, confocal microscopy, Western blot analysis, immunocytochemistry, and the fear conditioning test. RESULTS: Here we show that isoflurane, but not desflurane, induces opening of mitochondrial permeability transition pore (mPTP), increase in levels of reactive oxygen species, reduction in levels of mitochondrial membrane potential and adenosine-5'-triphosphate, activation of caspase 3, and impairment of learning and memory in cultured cells, mouse hippocampus neurons, mouse hippocampus, and mice. Moreover, cyclosporine A, a blocker of mPTP opening, attenuates isoflurane-induced mPTP opening, caspase 3 activation, and impairment of learning and memory. Finally, isoflurane may induce the opening of mPTP via increasing levels of reactive oxygen species. INTERPRETATION: These findings suggest that desflurane could be a safer anesthetic for AD patients as compared to isoflurane, and elucidate the potential mitochondria-associated underlying mechanisms, and therefore have implications for use of anesthetics in AD patients, pending human study confirmation.


Asunto(s)
Anestésicos por Inhalación/efectos adversos , Isoflurano/análogos & derivados , Isoflurano/efectos adversos , Aprendizaje/efectos de los fármacos , Memoria/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Neuronas/efectos de los fármacos , Animales , Western Blotting , Línea Celular , Desflurano , Activación Enzimática/efectos de los fármacos , Citometría de Flujo , Humanos , Inmunohistoquímica , Ratones , Microscopía Confocal , Proteínas de Transporte de Membrana Mitocondrial/efectos de los fármacos , Poro de Transición de la Permeabilidad Mitocondrial , Neuronas/metabolismo , Especies Reactivas de Oxígeno/metabolismo
17.
Cell Mol Immunol ; 20(4): 389-403, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36788341

RESUMEN

Helminth-induced Th2 immunity and gut microbiota have been recently shown to be highly effective in modulating metabolic syndromes in animal models. This study aimed to determine whether maternal immunity and microbial factors affect the induction and development of obesity in offspring. Here, Heligomosomoides polygyrus (Hp)-infected or control female C57BL/6J mice mated with normal males and their offspring were fed a high-fat diet (HFD) for 9 weeks after weaning. Our results showed that Hp-induced maternal outcomes during gestation and lactation significantly impacted offspring metabolic phenotypes. This was evidenced by results showing that offspring from helminth-infected mothers on an HFD (Hp-offspring + HFD) gained significantly less body weight than those from uninfected mothers (Cont-offspring + HFD). Hp-offspring + HFD exhibited no Th2 phenotype but displayed a pattern of gut microbiota composition similar to that of Hp-infected mothers. Cross-fostering experiments confirmed that the helminth-induced maternal attenuation of offspring obesity was mediated through both prenatal and postnatal effects. Our results further showed that helminth-infected dams and their offspring had a markedly altered gut microbiome composition, with increased production of short-chain fatty acids (SCFAs). Intriguingly, Hp-infected mothers and Hp-offspring + HFD showed increased SCFA receptor (GPR) expression in adipose and colonic tissues compared to noninfected mothers and Cont-offspring + HFD, respectively. Moreover, SCFA supplementation to the pups of uninfected control mothers during lactation protected against HFD-induced weight gain, which corresponded with changes in gut bacterial colonization. Collectively, our findings provide new insights into the complex interaction of maternal immune status and gut microbiome, Hp infection, and the immunity and gut microbiome in obese-prone offspring in infant life.


Asunto(s)
Helmintiasis , Helmintos , Microbiota , Animales , Embarazo , Ratones , Masculino , Femenino , Dieta Alta en Grasa/efectos adversos , Ratones Endogámicos C57BL , Obesidad , Ácidos Grasos Volátiles
18.
Br J Nutr ; 107(11): 1623-34, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21992995

RESUMEN

Modulation of the cellular response by the administration of probiotic bacteria may be an effective strategy for preventing or inhibiting tumour growth. We orally pre-inoculated mice with probiotics Lactobacillus acidophilus NCFM (La) for 14 d. Subcutaneous dorsal-flank tumours and segmental orthotopic colon cancers were implanted into mice using CT-26 murine colon adenocarcinoma cells. On day 28 after tumour initiation, the lamina propria of the colon, mesenteric lymph nodes (MLN) and spleen were harvested and purified for flow cytometry and mRNA analyses. We demonstrated that La pre-inoculation reduced tumour volume growth by 50·3 %, compared with untreated mice at 28 d after tumour implants (2465·5 (SEM 1290·4) v. 4950·9 (SEM 1689·3) mm³, P<0·001). Inoculation with La reduced the severity of colonic carcinogenesis caused by CT-26 cells, such as level of colonic involvement and structural abnormality of epithelial/crypt damage. Moreover, La enhanced apoptosis of CT-26 cells both in dorsal-flank tumour and segmental orthotopic colon cancer, and the mean counts of apoptotic body were higher in mice pre-inoculated with La (P<0·05) compared with untreated mice. La pre-inoculation down-regulated the CXCR4 mRNA expressions in the colon, MLN and extra-intestinal tissue, compared with untreated mice (P<0·05). In addition, La pre-inoculation reduced the mean fluorescence index of MHC class I (H-2Dd, -Kd and -Ld) in flow cytometry analysis. Taken together, these findings suggest that probiotics La may play a role in attenuating tumour growth during CT-26 cell carcinogenesis. The down-regulated expression of CXCR4 mRNA and MHC class I, as well as increasing apoptosis in tumour tissue, indicated that La may be associated with modulating the cellular response triggered by colon carcinogenesis.


Asunto(s)
Adenocarcinoma/prevención & control , Anticarcinógenos/uso terapéutico , Neoplasias del Colon/prevención & control , Lactobacillus acidophilus , Probióticos/uso terapéutico , Adenocarcinoma/metabolismo , Adenocarcinoma/patología , Adenocarcinoma/secundario , Animales , Apoptosis , Línea Celular Tumoral , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Femenino , Regulación Neoplásica de la Expresión Génica , Genes MHC Clase I , Metástasis Linfática/patología , Metástasis Linfática/prevención & control , Ratones , Ratones Endogámicos BALB C , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Trasplante de Neoplasias , ARN Mensajero/metabolismo , Distribución Aleatoria , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Neoplasias del Bazo/metabolismo , Neoplasias del Bazo/patología , Neoplasias del Bazo/prevención & control , Neoplasias del Bazo/secundario
19.
Nutr Rev ; 80(12): 2260-2274, 2022 11 07.
Artículo en Inglés | MEDLINE | ID: mdl-35674686

RESUMEN

CONTEXT: A multidisciplinary approach has been suggested to be the optimal form of treatment of fibromyalgia (FM). A research focus on nutritional therapy has developed in recent years, and this approach has been more frequently integrated into the recovery plan of patients with FM. OBJECTIVES: The interaction between the nutritional status and health of patients with FM is highlighted in this review, and possible dietary approaches to ameliorating the disease's effects are discussed. DATA SOURCES: FM research studies containing a nutrition or diet focus with a publication date between 2000 and 2021 were scanned broadly through a computerized search of the MEDLINE, PubMed, and Web of Science databases. STUDY SELECTION: Studies that included the following criteria were eligible for inclusion: (1) original research and case studies that evaluated obesity and nutritional approaches as a therapeutic intervention for FM, and (2) patients older than 18 years who were diagnosed withFM according to the 1990 American College of Rheumatology criteria. DATA EXTRACTION: Interventions included nutritional supplementation, nutrient- and obesity-related blood analyses, prescribed diets, body mass index or obesity and quality-of-life assessments, weight reduction, food-additive elimination, and evaluation of food perception and food sensitivity. RESULTS: After the literature search, 36 studies (N = 5142 individuals) were identified as relevant, and their full texts were assessed for inclusion in the review. Conditions such as obesity, food allergies, nutritional deficiencies, and food additives were revealed to be risk factors that correlated with complications of FM. Several studies showed beneficial effects for patients with FM of high-antioxidant, high-fiber foods such as fruits and vegetables, low processed foods, high-quality proteins, and healthy fats. CONCLUSION: There is no specific diet therapy for the treatment of FM. However, overall, studies indicated that weight control, modified high-antioxidant diets, and nutritional supplementation are beneficial in alleviating symptoms in patients with FM.


Asunto(s)
Fibromialgia , Humanos , Fibromialgia/terapia , Antioxidantes , Dieta , Estado Nutricional , Obesidad
20.
Front Immunol ; 13: 817062, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35281070

RESUMEN

Food allergies and other immune-mediated diseases have become serious health concerns amongst infants and children in developed and developing countries. The absence of available cures limits disease management to allergen avoidance and symptomatic treatments. Research has suggested that the presence of maternal food allergies may expose the offspring to genetic predisposition, making them more susceptible to allergen sensitization. The following review has focused on epidemiologic studies regarding maternal influences of proneness to develop food allergy in offspring. The search strategy was "food allergy OR maternal effects OR offspring OR prevention". A systematically search from PubMed/MEDLINE, Science Direct and Google Scholar was conducted. Specifically, it discussed the effects of maternal immunity, microbiota, breastfeeding, genotype and allergy exposure on the development of food allergy in offspring. In addition, several commonly utilized prenatal and postpartum strategies to reduce food allergy proneness were presented, including early diagnosis of high-risk infants and various dietary interventions.


Asunto(s)
Hipersensibilidad a los Alimentos , Alérgenos , Lactancia Materna , Niño , Femenino , Hipersensibilidad a los Alimentos/epidemiología , Hipersensibilidad a los Alimentos/prevención & control , Humanos , Lactante , Periodo Posparto , Embarazo
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