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1.
Immunity ; 50(1): 212-224.e4, 2019 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-30650377

RESUMEN

Microbiota are thought to influence the development and progression of inflammatory bowel disease (IBD), but determining generalizable effects of microbiota on IBD etiology requires larger-scale functional analyses. We colonized germ-free mice with intestinal microbiotas from 30 healthy and IBD donors and determined the homeostatic intestinal T cell response to each microbiota. Compared to microbiotas from healthy donors, transfer of IBD microbiotas into germ-free mice increased numbers of intestinal Th17 cells and Th2 cells and decreased numbers of RORγt+ Treg cells. Colonization with IBD microbiotas exacerbated disease in a model where colitis is induced upon transfer of naive T cells into Rag1-/- mice. The proportions of Th17 and RORγt+ Treg cells induced by each microbiota were predictive of human disease status and accounted for disease severity in the Rag1-/- colitis model. Thus, an impact on intestinal Th17 and RORγt+ Treg cell compartments emerges as a unifying feature of IBD microbiotas, suggesting a general mechanism for microbial contribution to IBD pathogenesis.


Asunto(s)
Colitis/microbiología , Microbioma Gastrointestinal/genética , Enfermedades Inflamatorias del Intestino/inmunología , Enfermedades Inflamatorias del Intestino/microbiología , ARN Ribosómico 16S/genética , Linfocitos T Reguladores/inmunología , Células Th17/metabolismo , Animales , Diferenciación Celular , Colitis/inducido químicamente , Colitis/inmunología , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Homeostasis , Humanos , Ratones , Ratones Endogámicos C57BL , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo
2.
Gastroenterology ; 154(4): 1037-1046.e2, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29174952

RESUMEN

BACKGROUND & AIMS: It is not clear how the complex interactions between diet and the intestinal microbiota affect development of mucosal inflammation or inflammatory bowel disease. We investigated interactions between dietary ingredients, nutrients, and the microbiota in specific pathogen-free (SPF) and germ-free (GF) mice given more than 40 unique diets; we quantified individual and synergistic effects of dietary macronutrients and the microbiota on intestinal health and development of colitis. METHODS: C56BL/6J SPF and GF mice were placed on custom diets containing different concentrations and sources of protein, fat, digestible carbohydrates, and indigestible carbohydrates (fiber). After 1 week, SPF and GF mice were given dextran sulfate sodium (DSS) to induce colitis. Disease severity was determined based on the percent weight change from baseline, and modeled as a function of the concentration of each macronutrient in the diet. In unchallenged mice, we measured intestinal permeability by feeding mice labeled dextran and measuring levels in blood. Feces were collected and microbiota were analyzed by 16S rDNA sequencing. We collected colons from mice and performed transcriptome analyses. RESULTS: Fecal microbiota varied with diet; the concentration of protein and fiber had the strongest effect on colitis development. Among 9 fiber sources tested, psyllium, pectin, and cellulose fiber reduced the severity of colitis in SPF mice, whereas methylcellulose increased severity. Increasing dietary protein increased the density of the fecal microbiota and the severity of colitis in SPF mice, but not in GF mice or mice given antibiotics. Psyllium fiber reduced the severity of colitis through microbiota-dependent and microbiota-independent mechanisms. Combinatorial perturbations to dietary casein protein and psyllium fiber in parallel accounted for most variation in gut microbial density and intestinal permeability in unchallenged mice, as well as the severity of DSS-induced colitis; changes in 1 ingredient could be offset by changes in another. CONCLUSIONS: In an analysis of the effects of different dietary components and the gut microbiota on mice with and without DSS-induced colitis, we found complex mixtures of nutrients affect intestinal permeability, gut microbial density, and development of intestinal inflammation.


Asunto(s)
Bacterias/crecimiento & desarrollo , Colitis/microbiología , Colon/microbiología , Dieta , Microbioma Gastrointestinal , Alimentación Animal , Animales , Bacterias/clasificación , Bacterias/aislamiento & purificación , Caseínas/administración & dosificación , Colitis/metabolismo , Colitis/fisiopatología , Colitis/prevención & control , Colon/metabolismo , Colon/fisiopatología , Sulfato de Dextran , Dieta/efectos adversos , Fibras de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Modelos Animales de Enfermedad , Heces/microbiología , Femenino , Proteínas de Homeodominio/genética , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Estado Nutricional , Valor Nutritivo , Permeabilidad , Psyllium/administración & dosificación , Índice de Severidad de la Enfermedad , Factores de Tiempo
3.
Elife ; 82019 01 22.
Artículo en Inglés | MEDLINE | ID: mdl-30666957

RESUMEN

To identify factors that regulate gut microbiota density and the impact of varied microbiota density on health, we assayed this fundamental ecosystem property in fecal samples across mammals, human disease, and therapeutic interventions. Physiologic features of the host (carrying capacity) and the fitness of the gut microbiota shape microbiota density. Therapeutic manipulation of microbiota density in mice altered host metabolic and immune homeostasis. In humans, gut microbiota density was reduced in Crohn's disease, ulcerative colitis, and ileal pouch-anal anastomosis. The gut microbiota in recurrent Clostridium difficile infection had lower density and reduced fitness that were restored by fecal microbiota transplantation. Understanding the interplay between microbiota and disease in terms of microbiota density, host carrying capacity, and microbiota fitness provide new insights into microbiome structure and microbiome targeted therapeutics. Editorial note: This article has been through an editorial process in which the authors decide how to respond to the issues raised during peer review. The Reviewing Editor's assessment is that all the issues have been addressed (see decision letter).


Asunto(s)
Infecciones por Clostridium/microbiología , Enfermedad de Crohn/microbiología , Trasplante de Microbiota Fecal , Microbioma Gastrointestinal , Adiposidad , Adulto , Anciano , Anciano de 80 o más Años , Animales , Clostridioides difficile , Femenino , Homeostasis , Humanos , Íleon/microbiología , Sistema Inmunológico , Enfermedades Inflamatorias del Intestino , Masculino , Ratones , Ratones Endogámicos C57BL , Microbiota , Persona de Mediana Edad , Membrana Mucosa/microbiología , Fenotipo , ARN Ribosómico 16S/metabolismo , Especificidad de la Especie , Adulto Joven
4.
Nat Genet ; 49(10): 1437-1449, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28892060

RESUMEN

A major challenge in inflammatory bowel disease (IBD) is the integration of diverse IBD data sets to construct predictive models of IBD. We present a predictive model of the immune component of IBD that informs causal relationships among loci previously linked to IBD through genome-wide association studies (GWAS) using functional and regulatory annotations that relate to the cells, tissues, and pathophysiology of IBD. Our model consists of individual networks constructed using molecular data generated from intestinal samples isolated from three populations of patients with IBD at different stages of disease. We performed key driver analysis to identify genes predicted to modulate network regulatory states associated with IBD, prioritizing and prospectively validating 12 of the top key drivers experimentally. This validated key driver set not only introduces new regulators of processes central to IBD but also provides the integrated circuits of genetic, molecular, and clinical traits that can be directly queried to interrogate and refine the regulatory framework defining IBD.


Asunto(s)
Redes Reguladoras de Genes , Genes Reguladores , Genómica/métodos , Enfermedades Inflamatorias del Intestino/genética , Modelos Genéticos , Traslado Adoptivo , Animales , Causalidad , Células Cultivadas , Colitis/inducido químicamente , Colitis/genética , Conjuntos de Datos como Asunto , Modelos Animales de Enfermedad , Femenino , Técnicas de Silenciamiento del Gen , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , Mucosa Intestinal/metabolismo , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , ARN Interferente Pequeño/genética , Subgrupos de Linfocitos T/trasplante , Transcriptoma
6.
PLoS One ; 8(9): e75302, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24086502

RESUMEN

Recent progress toward an HIV vaccine highlights both the potential of vaccines to end the AIDS pandemic and the need to boost efficacy by incorporating additional vaccine strategies. Although many aspects of the immune response can contribute to vaccine efficacy, the key factors have not been defined fully yet. A particular area that may yield new insights is anti-glycan immune responses, such as those against the glycan shield that HIV uses to evade the immune system. In this study, we used glycan microarray technology to evaluate anti-glycan antibody responses induced by SIV vaccination and infection in a non-human primate model of HIV infection. This comprehensive profiling of circulating anti-glycan antibodies found changes in anti-glycan antibody levels after both vaccination with the Ad5hr-SIV vaccine and SIV infection. Notably, SIV infection produced generalized declines in anti-glycan IgM antibodies in a number of animals. Additionally, some infected animals generated antibodies to the Tn antigen, which is a cryptic tumor-associated antigen exposed by premature termination of O-linked glycans; however, the Ad5hr-SIV vaccine did not induce anti-Tn IgG antibodies. Overall, this study demonstrates the potential contributions that glycan microarrays can make for HIV vaccine development.


Asunto(s)
Anticuerpos Antivirales/inmunología , Inmunidad Humoral/inmunología , Infecciones por Lentivirus/prevención & control , Polisacáridos/inmunología , Vacunas contra el SIDAS/inmunología , Animales , Linfocitos T CD4-Positivos/inmunología , Ensayos Analíticos de Alto Rendimiento/métodos , Humanos , Inmunoglobulinas/sangre , Macaca mulatta , Análisis por Micromatrices , Polisacáridos/metabolismo , Carga Viral
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