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1.
Cell ; 187(5): 1206-1222.e16, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38428395

RESUMEN

Plasmids are extrachromosomal genetic elements that often encode fitness-enhancing features. However, many bacteria carry "cryptic" plasmids that do not confer clear beneficial functions. We identified one such cryptic plasmid, pBI143, which is ubiquitous across industrialized gut microbiomes and is 14 times as numerous as crAssphage, currently established as the most abundant extrachromosomal genetic element in the human gut. The majority of mutations in pBI143 accumulate in specific positions across thousands of metagenomes, indicating strong purifying selection. pBI143 is monoclonal in most individuals, likely due to the priority effect of the version first acquired, often from one's mother. pBI143 can transfer between Bacteroidales, and although it does not appear to impact bacterial host fitness in vivo, it can transiently acquire additional genetic content. We identified important practical applications of pBI143, including its use in identifying human fecal contamination and its potential as an alternative approach to track human colonic inflammatory states.


Asunto(s)
Bacterias , Tracto Gastrointestinal , Metagenoma , Plásmidos , Humanos , Bacterias/genética , Bacteroidetes/genética , Heces/microbiología , Plásmidos/genética
2.
Cell ; 179(5): 1068-1083.e21, 2019 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-31730850

RESUMEN

Ocean microbial communities strongly influence the biogeochemistry, food webs, and climate of our planet. Despite recent advances in understanding their taxonomic and genomic compositions, little is known about how their transcriptomes vary globally. Here, we present a dataset of 187 metatranscriptomes and 370 metagenomes from 126 globally distributed sampling stations and establish a resource of 47 million genes to study community-level transcriptomes across depth layers from pole-to-pole. We examine gene expression changes and community turnover as the underlying mechanisms shaping community transcriptomes along these axes of environmental variation and show how their individual contributions differ for multiple biogeochemically relevant processes. Furthermore, we find the relative contribution of gene expression changes to be significantly lower in polar than in non-polar waters and hypothesize that in polar regions, alterations in community activity in response to ocean warming will be driven more strongly by changes in organismal composition than by gene regulatory mechanisms. VIDEO ABSTRACT.


Asunto(s)
Regulación de la Expresión Génica , Metagenoma , Océanos y Mares , Transcriptoma/genética , Geografía , Microbiota/genética , Anotación de Secuencia Molecular , ARN Mensajero/genética , ARN Mensajero/metabolismo , Agua de Mar/microbiología , Temperatura
3.
Immunity ; 56(1): 143-161.e11, 2023 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-36630913

RESUMEN

Although T cells can exert potent anti-tumor immunity, a subset of T helper (Th) cells producing interleukin-22 (IL-22) in breast and lung tumors is linked to dismal patient outcome. Here, we examined the mechanisms whereby these T cells contribute to disease. In murine models of lung and breast cancer, constitutional and T cell-specific deletion of Il22 reduced metastases without affecting primary tumor growth. Deletion of the IL-22 receptor on cancer cells decreases metastasis to a degree similar to that seen in IL-22-deficient mice. IL-22 induced high expression of CD155, which bound to the activating receptor CD226 on NK cells. Excessive activation led to decreased amounts of CD226 and functionally impaired NK cells, which elevated the metastatic burden. IL-22 signaling was also associated with CD155 expression in human datasets and with poor patient outcomes. Taken together, our findings reveal an immunosuppressive circuit activated by T cell-derived IL-22 that promotes lung metastasis.


Asunto(s)
Interleucinas , Neoplasias , Receptores Virales , Linfocitos T Colaboradores-Inductores , Animales , Humanos , Ratones , Antígenos de Diferenciación de Linfocitos T/metabolismo , Interleucinas/genética , Interleucinas/metabolismo , Células Asesinas Naturales/metabolismo , Neoplasias/metabolismo , Unión Proteica , Linfocitos T Colaboradores-Inductores/metabolismo , Interleucina-22
4.
Cell ; 163(3): 746-58, 2015 Oct 22.
Artículo en Inglés | MEDLINE | ID: mdl-26496612

RESUMEN

A key effector route of the Sugar Code involves lectins that exert crucial regulatory controls by targeting distinct cellular glycans. We demonstrate that a single amino-acid substitution in a banana lectin, replacing histidine 84 with a threonine, significantly reduces its mitogenicity, while preserving its broad-spectrum antiviral potency. X-ray crystallography, NMR spectroscopy, and glycocluster assays reveal that loss of mitogenicity is strongly correlated with loss of pi-pi stacking between aromatic amino acids H84 and Y83, which removes a wall separating two carbohydrate binding sites, thus diminishing multivalent interactions. On the other hand, monovalent interactions and antiviral activity are preserved by retaining other wild-type conformational features and possibly through unique contacts involving the T84 side chain. Through such fine-tuning, target selection and downstream effects of a lectin can be modulated so as to knock down one activity, while preserving another, thus providing tools for therapeutics and for understanding the Sugar Code.


Asunto(s)
Lectinas de Plantas/química , Lectinas de Plantas/genética , Fármacos Anti-VIH/química , Secuencia de Carbohidratos , Ingeniería Genética , Mitógenos/química , Modelos Moleculares , Simulación de Dinámica Molecular , Musa/química
5.
Nature ; 626(7998): 377-384, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38109938

RESUMEN

Many of the Earth's microbes remain uncultured and understudied, limiting our understanding of the functional and evolutionary aspects of their genetic material, which remain largely overlooked in most metagenomic studies1. Here we analysed 149,842 environmental genomes from multiple habitats2-6 and compiled a curated catalogue of 404,085 functionally and evolutionarily significant novel (FESNov) gene families exclusive to uncultivated prokaryotic taxa. All FESNov families span multiple species, exhibit strong signals of purifying selection and qualify as new orthologous groups, thus nearly tripling the number of bacterial and archaeal gene families described to date. The FESNov catalogue is enriched in clade-specific traits, including 1,034 novel families that can distinguish entire uncultivated phyla, classes and orders, probably representing synapomorphies that facilitated their evolutionary divergence. Using genomic context analysis and structural alignments we predicted functional associations for 32.4% of FESNov families, including 4,349 high-confidence associations with important biological processes. These predictions provide a valuable hypothesis-driven framework that we used for experimental validatation of a new gene family involved in cell motility and a novel set of antimicrobial peptides. We also demonstrate that the relative abundance profiles of novel families can discriminate between environments and clinical conditions, leading to the discovery of potentially new biomarkers associated with colorectal cancer. We expect this work to enhance future metagenomics studies and expand our knowledge of the genetic repertory of uncultivated organisms.


Asunto(s)
Archaea , Bacterias , Ecosistema , Evolución Molecular , Genes Arqueales , Genes Bacterianos , Genómica , Conocimiento , Péptidos Antimicrobianos/genética , Archaea/clasificación , Archaea/genética , Bacterias/clasificación , Bacterias/genética , Biomarcadores , Movimiento Celular/genética , Neoplasias Colorrectales/genética , Genómica/métodos , Genómica/tendencias , Metagenómica/tendencias , Familia de Multigenes , Filogenia , Reproducibilidad de los Resultados
6.
Nature ; 627(8005): 772-777, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38538941

RESUMEN

The encoding of qubits in semiconductor spin carriers has been recognized as a promising approach to a commercial quantum computer that can be lithographically produced and integrated at scale1-10. However, the operation of the large number of qubits required for advantageous quantum applications11-13 will produce a thermal load exceeding the available cooling power of cryostats at millikelvin temperatures. As the scale-up accelerates, it becomes imperative to establish fault-tolerant operation above 1 K, at which the cooling power is orders of magnitude higher14-18. Here we tune up and operate spin qubits in silicon above 1 K, with fidelities in the range required for fault-tolerant operations at these temperatures19-21. We design an algorithmic initialization protocol to prepare a pure two-qubit state even when the thermal energy is substantially above the qubit energies and incorporate radiofrequency readout to achieve fidelities up to 99.34% for both readout and initialization. We also demonstrate single-qubit Clifford gate fidelities up to 99.85% and a two-qubit gate fidelity of 98.92%. These advances overcome the fundamental limitation that the thermal energy must be well below the qubit energies for the high-fidelity operation to be possible, surmounting a main obstacle in the pathway to scalable and fault-tolerant quantum computation.

7.
Nature ; 604(7907): 635-642, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35478233

RESUMEN

The prosperity and lifestyle of our society are very much governed by achievements in condensed matter physics, chemistry and materials science, because new products for sectors such as energy, the environment, health, mobility and information technology (IT) rely largely on improved or even new materials. Examples include solid-state lighting, touchscreens, batteries, implants, drug delivery and many more. The enormous amount of research data produced every day in these fields represents a gold mine of the twenty-first century. This gold mine is, however, of little value if these data are not comprehensively characterized and made available. How can we refine this feedstock; that is, turn data into knowledge and value? For this, a FAIR (findable, accessible, interoperable and reusable) data infrastructure is a must. Only then can data be readily shared and explored using data analytics and artificial intelligence (AI) methods. Making data 'findable and AI ready' (a forward-looking interpretation of the acronym) will change the way in which science is carried out today. In this Perspective, we discuss how we can prepare to make this happen for the field of materials science.


Asunto(s)
Inteligencia Artificial , Ciencia de los Datos
8.
Nature ; 607(7917): 111-118, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35732736

RESUMEN

Natural microbial communities are phylogenetically and metabolically diverse. In addition to underexplored organismal groups1, this diversity encompasses a rich discovery potential for ecologically and biotechnologically relevant enzymes and biochemical compounds2,3. However, studying this diversity to identify genomic pathways for the synthesis of such compounds4 and assigning them to their respective hosts remains challenging. The biosynthetic potential of microorganisms in the open ocean remains largely uncharted owing to limitations in the analysis of genome-resolved data at the global scale. Here we investigated the diversity and novelty of biosynthetic gene clusters in the ocean by integrating around 10,000 microbial genomes from cultivated and single cells with more than 25,000 newly reconstructed draft genomes from more than 1,000 seawater samples. These efforts revealed approximately 40,000 putative mostly new biosynthetic gene clusters, several of which were found in previously unsuspected phylogenetic groups. Among these groups, we identified a lineage rich in biosynthetic gene clusters ('Candidatus Eudoremicrobiaceae') that belongs to an uncultivated bacterial phylum and includes some of the most biosynthetically diverse microorganisms in this environment. From these, we characterized the phospeptin and pythonamide pathways, revealing cases of unusual bioactive compound structure and enzymology, respectively. Together, this research demonstrates how microbiomics-driven strategies can enable the investigation of previously undescribed enzymes and natural products in underexplored microbial groups and environments.


Asunto(s)
Vías Biosintéticas , Microbiota , Océanos y Mares , Bacterias/clasificación , Bacterias/genética , Vías Biosintéticas/genética , Genómica , Microbiota/genética , Familia de Multigenes/genética , Filogenia
9.
EMBO J ; 41(13): e109996, 2022 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-35767364

RESUMEN

Helicobacter pylori is a pathogen that colonizes the stomach and causes chronic gastritis. Helicobacter pylori can colonize deep inside gastric glands, triggering increased R-spondin 3 (Rspo3) signaling. This causes an expansion of the "gland base module," which consists of self-renewing stem cells and antimicrobial secretory cells and results in gland hyperplasia. The contribution of Rspo3 receptors Lgr4 and Lgr5 is not well explored. Here, we identified that Lgr4 regulates Lgr5 expression and is required for H. pylori-induced hyperplasia and inflammation, while Lgr5 alone is not. Using conditional knockout mice, we reveal that R-spondin signaling via Lgr4 drives proliferation of stem cells and also induces NF-κB activity in the proliferative stem cells. Upon exposure to H. pylori, the Lgr4-driven NF-κB activation is responsible for the expansion of the gland base module and simultaneously enables chemokine expression in stem cells, resulting in gland hyperplasia and neutrophil recruitment. This demonstrates a connection between R-spondin-Lgr and NF-κB signaling that links epithelial stem cell behavior and inflammatory responses to gland-invading H. pylori.


Asunto(s)
Helicobacter pylori , Animales , Hiperplasia/metabolismo , Hiperplasia/patología , Inflamación/patología , Ratones , FN-kappa B/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Células Madre/metabolismo , Estómago
10.
Nat Immunol ; 15(11): 1079-89, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25282160

RESUMEN

Humoral autoimmunity paralleled by the accumulation of follicular helper T cells (T(FH) cells) is linked to mutation of the gene encoding the RNA-binding protein roquin-1. Here we found that T cells lacking roquin caused pathology in the lung and accumulated as cells of the T(H)17 subset of helper T cells in the lungs. Roquin inhibited T(H)17 cell differentiation and acted together with the endoribonuclease regnase-1 to repress target mRNA encoding the T(H)17 cell-promoting factors IL-6, ICOS, c-Rel, IRF4, IκBNS and IκBζ. This cooperation required binding of RNA by roquin and the nuclease activity of regnase-1. Upon recognition of antigen by the T cell antigen receptor (TCR), roquin and regnase-1 proteins were cleaved by the paracaspase MALT1. Thus, this pathway acts as a 'rheostat' by translating TCR signal strength via graded inactivation of post-transcriptional repressors and differential derepression of targets to enhance T(H)17 differentiation.


Asunto(s)
Caspasas/metabolismo , Proteínas de Neoplasias/metabolismo , Receptores de Antígenos de Linfocitos T/inmunología , Ribonucleasas/metabolismo , Células Th17/citología , Ubiquitina-Proteína Ligasas/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Secuencia de Aminoácidos , Animales , Sitios de Unión/inmunología , Diferenciación Celular/inmunología , Línea Celular , Genes rel/genética , Células HEK293 , Humanos , Proteína Coestimuladora de Linfocitos T Inducibles/genética , Factores Reguladores del Interferón/genética , Interleucina-6/genética , Péptidos y Proteínas de Señalización Intracelular , Pulmón/inmunología , Pulmón/patología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Ratones Noqueados , Proteína 1 de la Translocación del Linfoma del Tejido Linfático Asociado a Mucosas , Proteínas Nucleares/genética , Proteínas/genética , ARN Mensajero/genética , Proteínas de Unión al ARN/metabolismo , Alineación de Secuencia , Células Th17/inmunología , Ubiquitina-Proteína Ligasas/genética
11.
Blood ; 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38657197

RESUMEN

Thrombotic microangiopathy (TMA) is characterized by immunothrombosis and life-threatening organ failure, but the precise underlying mechanism driving its pathogenesis remains elusive. In this study, we hypothesized that gasdermin D (GSDMD), a pore-forming protein serving as the final downstream effector of pyroptosis/interleukin (IL)-1pathway, contributes to TMA and its consequences by amplifying neutrophil maturation and subsequent necrosis. Using a murine model of focal crystalline TMA, we found that Gsdmd-deficiency ameliorated immunothrombosis, acute tissue injury and failure. Gsdmd-/- mice exhibited a decrease in mature IL-1, as well as in neutrophil maturation, 2 integrin activation, and recruitment to TMA lesions, where they formed reduced neutrophil extracellular traps both in arteries and interstitial tissue. The GSDMD inhibitor disulfiram dose-dependently suppressed human neutrophil pyroptosis in response to cholesterol crystals. Experiments with GSDMD-deficient human induced pluripotent stem cell-derived neutrophils confirmed the involvement of GSDMD in neutrophil 2 integrin activation, maturation as well as pyroptosis. Both prophylactic and therapeutic administration of disulfiram protected mice from focal TMA, acute tissue injury and failure. Our data identify GSDMD as a key mediator of focal crystalline TMA and its consequences: ischemic tissue infarction and organ failure. GSDMD could potentially serve as a therapeutic target for systemic forms of TMA.

12.
Nucleic Acids Res ; 52(D1): D777-D783, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-37897342

RESUMEN

Meta'omic data on microbial diversity and function accrue exponentially in public repositories, but derived information is often siloed according to data type, study or sampled microbial environment. Here we present SPIRE, a Searchable Planetary-scale mIcrobiome REsource that integrates various consistently processed metagenome-derived microbial data modalities across habitats, geography and phylogeny. SPIRE encompasses 99 146 metagenomic samples from 739 studies covering a wide array of microbial environments and augmented with manually-curated contextual data. Across a total metagenomic assembly of 16 Tbp, SPIRE comprises 35 billion predicted protein sequences and 1.16 million newly constructed metagenome-assembled genomes (MAGs) of medium or high quality. Beyond mapping to the high-quality genome reference provided by proGenomes3 (http://progenomes.embl.de), these novel MAGs form 92 134 novel species-level clusters, the majority of which are unclassified at species level using current tools. SPIRE enables taxonomic profiling of these species clusters via an updated, custom mOTUs database (https://motu-tool.org/) and includes several layers of functional annotation, as well as crosslinks to several (micro-)biological databases. The resource is accessible, searchable and browsable via http://spire.embl.de.


Asunto(s)
Bases de Datos Factuales , Metagenoma , Microbiota , Metagenómica , Microbiota/genética
13.
Trends Biochem Sci ; 46(11): 931-943, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34294544

RESUMEN

Naturally occurring DNA, RNA, and proteins predominantly exist in only one enantiomeric form (homochirality). Advances in biotechnology and chemical synthesis allow the production of the respective alternate enantiomeric form, enabling access to mirror-image versions of these natural biopolymers. Exploiting the unique properties of such mirror molecules has already led to many applications, such as biostable and nonimmunogenic therapeutics or sensors. However, a 'roadblock' for unlocking the mirror world is the lack of biological systems capable of synthesizing critical building blocks including mirror oligonucleotides and oligopeptides to reducing cost and improve purity. Here, we provide an overview of the current progress, applications, and challenges of the molecular mirror world by identifying milestones towards mirroring life.


Asunto(s)
Proteínas , ARN , ADN , ARN/química , Estereoisomerismo
14.
EMBO J ; 40(13): e106272, 2021 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-33942347

RESUMEN

Cellular stress has been associated with inflammation, yet precise underlying mechanisms remain elusive. In this study, various unrelated stress inducers were employed to screen for sensors linking altered cellular homeostasis and inflammation. We identified the intracellular pattern recognition receptors NOD1/2, which sense bacterial peptidoglycans, as general stress sensors detecting perturbations of cellular homeostasis. NOD1/2 activation upon such perturbations required generation of the endogenous metabolite sphingosine-1-phosphate (S1P). Unlike peptidoglycan sensing via the leucine-rich repeats domain, cytosolic S1P directly bound to the nucleotide binding domains of NOD1/2, triggering NF-κB activation and inflammatory responses. In sum, we unveiled a hitherto unknown role of NOD1/2 in surveillance of cellular homeostasis through sensing of the cytosolic metabolite S1P. We propose S1P, an endogenous metabolite, as a novel NOD1/2 activator and NOD1/2 as molecular hubs integrating bacterial and metabolic cues.


Asunto(s)
Inflamación/metabolismo , Lisofosfolípidos/metabolismo , Proteína Adaptadora de Señalización NOD1/metabolismo , Proteína Adaptadora de Señalización NOD2/metabolismo , Esfingosina/análogos & derivados , Animales , Línea Celular , Línea Celular Tumoral , Femenino , Células HEK293 , Células HeLa , Humanos , Ratones , FN-kappa B/metabolismo , Peptidoglicano/metabolismo , Transducción de Señal/fisiología , Esfingosina/metabolismo , Células THP-1
15.
Lancet ; 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38971175

RESUMEN

BACKGROUND: Intensified systemic chemotherapy has the highest primary cure rate for advanced-stage, classical Hodgkin lymphoma but this comes with a cost of severe and potentially life long, persisting toxicities. With the new regimen of brentuximab vedotin, etoposide, cyclophosphamide, doxorubicin, dacarbazine, and dexamethasone (BrECADD), we aimed to improve the risk-to-benefit ratio of treatment of advanced-stage, classical Hodgkin lymphoma guided by PET after two cycles. METHODS: This randomised, multicentre, parallel, open-label, phase 3 trial was done in 233 trial sites across nine countries. Eligible patients were adults (aged ≤60 years) with newly diagnosed, advanced-stage, classical Hodgkin lymphoma (ie, Ann Arbor stage III/IV, stage II with B symptoms, and either one or both risk factors of large mediastinal mass and extranodal lesions). Patients were randomly assigned (1:1) to four or six cycles (21-day intervals) of escalated doses of etoposide (200 mg/m2 intravenously on days 1-3), doxorubicin (35 mg/m2 intravenously on day 1), and cyclophosphamide (1250 mg/m2 intravenously on day 1), and standard doses of bleomycin (10 mg/m2 intravenously on day 8), vincristine (1·4 mg/m2 intravenously on day 8), procarbazine (100 mg/m2 orally on days 1-7), and prednisone (40 mg/m2 orally on days 1-14; eBEACOPP) or BrECADD, guided by PET after two cycles. Patients and investigators were not masked to treatment assignment. Hierarchical coprimary objectives were to show (1) improved tolerability defined by treatment-related morbidity and (2) non-inferior efficacy defined by progression-free survival with an absolute non-inferiority margin of 6 percentage points of BrECADD compared with eBEACOPP. An additional test of superiority of progression-free survival was to be done if non-inferiority had been established. Analyses were done by intention to treat; the treatment-related morbidity assessment required documentation of at least one chemotherapy cycle. This trial was registered at ClinicalTrials.gov (NCT02661503). FINDINGS: Between July 22, 2016, and Aug 27, 2020, 1500 patients were enrolled, of whom 749 were randomly assigned to BrECADD and 751 to eBEACOPP. 1482 patients were included in the intention-to-treat analysis. The median age of patients was 31 years (IQR 24-42). 838 (56%) of 1482 patients were male and 644 (44%) were female. Most patients were White (1352 [91%] of 1482). Treatment-related morbidity was significantly lower with BrECADD (312 [42%] of 738 patients) than with eBEACOPP (430 [59%] of 732 patients; relative risk 0·72 [95% CI 0·65-0·80]; p<0·0001). At a median follow-up of 48 months, BrECADD improved progression-free survival with a hazard ratio of 0·66 (0·45-0·97; p=0·035); 4-year progression-free survival estimates were 94·3% (95% CI 92·6-96·1) for BrECADD and 90·9% (88·7-93·1) for eBEACOPP. 4-year overall survival rates were 98·6% (97·7-99·5) and 98·2% (97·2-99·3), respectively. INTERPRETATION: BrECADD guided by PET after two cycles is better tolerated and more effective than eBEACOPP in first-line treatment of adult patients with advanced-stage, classical Hodgkin lymphoma. FUNDING: Takeda Oncology.

16.
Bioinformatics ; 40(2)2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-38341646

RESUMEN

MOTIVATION: DNA barcoding has become a powerful tool for assessing the fitness of strains in a variety of studies, including random transposon mutagenesis screens, attenuation of site-directed mutants, and population dynamics of isogenic strain pools. However, the statistical analysis, visualization, and contextualization of the data resulting from such experiments can be complex and require bioinformatic skills. RESULTS: Here, we developed mBARq, a user-friendly tool designed to simplify these steps for diverse experimental setups. The tool is seamlessly integrated with an intuitive web app for interactive data exploration via the STRING and KEGG databases to accelerate scientific discovery. AVAILABILITY AND IMPLEMENTATION: The tool is implemented in Python. The source code is freely available (https://github.com/MicrobiologyETHZ/mbarq) and the web app can be accessed at: https://microbiomics.io/tools/mbarq-app.


Asunto(s)
Código de Barras del ADN Taxonómico , Programas Informáticos , ADN , Biología Computacional
17.
Immunity ; 45(5): 1078-1092, 2016 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-27851911

RESUMEN

Th17 cells are most abundant in the gut, where their presence depends on the intestinal microbiota. Here, we examined whether intestinal Th17 cells contribute to extra-intestinal Th17 responses in autoimmune kidney disease. We found high frequencies of Th17 cells in the kidneys of patients with antineutrophil cytoplasmatic antibody (ANCA)-associated glomerulonephritis. We utilized photoconversion of intestinal cells in Kaede mice to track intestinal T cell mobilization upon glomerulonephritis induction, and we found that Th17 cells egress from the gut in a S1P-receptor-1-dependent fashion and subsequently migrate to the kidney via the CCL20/CCR6 axis. Depletion of intestinal Th17 cells in germ-free and antibiotic-treated mice ameliorated renal disease, whereas expansion of these cells upon Citrobacter rodentium infection exacerbated pathology. Thus, in some autoimmune settings, intestinal Th17 cells migrate into target organs, where they contribute to pathology. Targeting the intestinal Th17 cell "reservoir" may present a therapeutic strategy for these autoimmune disorders.


Asunto(s)
Enfermedades Autoinmunes/inmunología , Quimiotaxis de Leucocito/inmunología , Glomerulonefritis/inmunología , Receptores de Lisoesfingolípidos/inmunología , Células Th17/inmunología , Animales , Citrobacter rodentium , Modelos Animales de Enfermedad , Infecciones por Enterobacteriaceae/inmunología , Citometría de Flujo , Humanos , Intestinos/inmunología , Riñón/inmunología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptores de Esfingosina-1-Fosfato
18.
EMBO Rep ; 24(6): e55556, 2023 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-37103980

RESUMEN

Alzheimer's, Parkinson's and Huntington's diseases can be caused by mutations that enhance protein aggregation, but we still do not know enough about the molecular players of these pathways to develop treatments for these devastating diseases. Here, we screen for mutations that might enhance aggregation in Caenorhabditis elegans, to investigate the mechanisms that protect against dysregulated homeostasis. We report that the stomatin homologue UNC-1 activates neurohormonal signalling from the sulfotransferase SSU-1 in ASJ sensory/endocrine neurons. A putative hormone, produced in ASJ, targets the nuclear receptor NHR-1, which acts cell autonomously in the muscles to modulate polyglutamine repeat (polyQ) aggregation. A second nuclear receptor, DAF-12, functions oppositely to NHR-1 to maintain protein homeostasis. Transcriptomics analyses of unc-1 mutants revealed changes in the expression of genes involved in fat metabolism, suggesting that fat metabolism changes, controlled by neurohormonal signalling, contribute to protein homeostasis. Furthermore, the enzymes involved in the identified signalling pathway are potential targets for treating neurodegenerative diseases caused by disrupted protein homeostasis.


Asunto(s)
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animales , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteostasis , Metabolismo de los Lípidos/genética , Receptores Citoplasmáticos y Nucleares/metabolismo , Esteroides/metabolismo
19.
J Immunol ; 210(5): 668-680, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36695776

RESUMEN

The chicken MHC is known to confer decisive resistance or susceptibility to various economically important pathogens, including the iconic oncogenic herpesvirus that causes Marek's disease (MD). Only one classical class I gene, BF2, is expressed at a high level in chickens, so it was relatively easy to discern a hierarchy from well-expressed thermostable fastidious specialist alleles to promiscuous generalist alleles that are less stable and expressed less on the cell surface. The class I molecule BF2*1901 is better expressed and more thermostable than the closely related BF2*1501, but the peptide motif was not simpler as expected. In this study, we confirm for newly developed chicken lines that the chicken MHC haplotype B15 confers resistance to MD compared with B19. Using gas phase sequencing and immunopeptidomics, we find that BF2*1901 binds a greater variety of amino acids in some anchor positions than does BF2*1501. However, by x-ray crystallography, we find that the peptide-binding groove of BF2*1901 is narrower and shallower. Although the self-peptides that bound to BF2*1901 may appear more various than those of BF2*1501, the structures show that the wider and deeper peptide-binding groove of BF2*1501 allows stronger binding and thus more peptides overall, correlating with the expected hierarchies for expression level, thermostability, and MD resistance. Our study provides a reasonable explanation for greater promiscuity for BF2*1501 compared with BF2*1901, corresponding to the difference in resistance to MD.


Asunto(s)
Enfermedad de Marek , Animales , Alelos , Aminoácidos , Membrana Celular , Pollos , Enfermedad de Marek/genética , Antígenos de Histocompatibilidad Clase I/inmunología
20.
J Immunol ; 211(11): 1669-1679, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37850963

RESUMEN

T regulatory type 1 (Tr1) cells, which are defined by their regulatory function, lack of Foxp3, and high expression of IL-10, CD49b, and LAG-3, are known to be able to suppress Th1 and Th17 in the intestine. Th1 and Th17 cells are also the main drivers of crescentic glomerulonephritis (GN), the most severe form of renal autoimmune disease. However, whether Tr1 cells emerge in renal inflammation and, moreover, whether they exhibit regulatory function during GN have not been thoroughly investigated yet. To address these questions, we used a mouse model of experimental crescentic GN and double Foxp3mRFP IL-10eGFP reporter mice. We found that Foxp3neg IL-10-producing CD4+ T cells infiltrate the kidneys during GN progression. Using single-cell RNA sequencing, we could show that these cells express the core transcriptional factors characteristic of Tr1 cells. In line with this, Tr1 cells showed a strong suppressive activity ex vivo and were protective in experimental crescentic GN in vivo. Finally, we could also identify Tr1 cells in the kidneys of patients with antineutrophil cytoplasmic autoantibody-associated GN and define their transcriptional profile. Tr1 cells are currently used in several immune-mediated inflammatory diseases, such as T-cell therapy. Thus, our study provides proof of concept for Tr1 cell-based therapies in experimental GN.


Asunto(s)
Glomerulonefritis , Linfocitos T Reguladores , Humanos , Ratones , Animales , Interleucina-10/metabolismo , Células Th17 , Riñón/metabolismo , Factores de Transcripción/metabolismo , Células TH1
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