Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.931
Filtrar
1.
Cell ; 183(1): 185-196.e14, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-33007262

RESUMO

Several HIV-1 and SIV vaccine candidates have shown partial protection against viral challenges in rhesus macaques. However, the protective efficacy of vaccine-elicited polyclonal antibodies has not previously been demonstrated in adoptive transfer studies in nonhuman primates. In this study, we show that passive transfer of purified antibodies from vaccinated macaques can protect naive animals against SIVmac251 challenges. We vaccinated 30 rhesus macaques with Ad26-SIV Env/Gag/Pol and SIV Env gp140 protein vaccines and assessed the induction of antibody responses and a putative protective signature. This signature included multiple antibody functions and correlated with upregulation of interferon pathways in vaccinated animals. Adoptive transfer of purified immunoglobulin G (IgG) from the vaccinated animals with the most robust protective signatures provided partial protection against SIVmac251 challenges in naive recipient rhesus macaques. These data demonstrate the protective efficacy of purified vaccine-elicited antiviral antibodies in this model, even in the absence of virus neutralization.


Assuntos
Imunização Passiva/métodos , Vacinas contra a SAIDS/imunologia , Vírus da Imunodeficiência Símia/imunologia , Vacinas contra a AIDS/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Formação de Anticorpos/imunologia , Produtos do Gene env/imunologia , Produtos do Gene gag/imunologia , Produtos do Gene pol/imunologia , HIV-1/imunologia , Imunoglobulina G/imunologia , Macaca mulatta/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia
2.
Nat Immunol ; 22(12): 1515-1523, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34811542

RESUMO

Development of an effective tuberculosis (TB) vaccine has suffered from an incomplete understanding of the correlates of protection against Mycobacterium tuberculosis (Mtb). Intravenous (i.v.) vaccination with Bacille Calmette-Guérin (BCG) provides nearly complete protection against TB in rhesus macaques, but the antibody response it elicits remains incompletely defined. Here we show that i.v. BCG drives superior antibody responses in the plasma and the lungs of rhesus macaques compared to traditional intradermal BCG administration. While i.v. BCG broadly expands antibody titers and functions, IgM titers in the plasma and lungs of immunized macaques are among the strongest markers of reduced bacterial burden. IgM was also enriched in macaques that received protective vaccination with an attenuated strain of Mtb. Finally, an Mtb-specific IgM monoclonal antibody reduced Mtb survival in vitro. Collectively, these data highlight the potential importance of IgM responses as a marker and mediator of protection against TB.


Assuntos
Anticorpos Antibacterianos/sangue , Vacina BCG/administração & dosagem , Imunogenicidade da Vacina , Imunoglobulina M/sangue , Mycobacterium tuberculosis/imunologia , Tuberculose/prevenção & controle , Vacinação , Administração Intravenosa , Animais , Biomarcadores/sangue , Modelos Animais de Doenças , Interações Hospedeiro-Patógeno , Macaca mulatta , Mycobacterium tuberculosis/patogenicidade , Fatores de Tempo , Tuberculose/imunologia , Tuberculose/microbiologia
3.
Cell ; 165(3): 656-67, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-27085913

RESUMO

The earliest events following mucosal HIV-1 infection, prior to measurable viremia, remain poorly understood. Here, by detailed necropsy studies, we show that the virus can rapidly disseminate following mucosal SIV infection of rhesus monkeys and trigger components of the inflammasome, both at the site of inoculation and at early sites of distal virus spread. By 24 hr following inoculation, a proinflammatory signature that lacked antiviral restriction factors was observed in viral RNA-positive tissues. The early innate response included expression of NLRX1, which inhibits antiviral responses, and activation of the TGF-ß pathway, which negatively regulates adaptive immune responses. These data suggest a model in which the virus triggers specific host mechanisms that suppress the generation of antiviral innate and adaptive immune responses in the first few days of infection, thus facilitating its own replication. These findings have important implications for the development of vaccines and other strategies to prevent infection.


Assuntos
Inflamassomos/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/imunologia , Síndrome de Imunodeficiência Adquirida dos Símios/virologia , Vírus da Imunodeficiência Símia/fisiologia , Animais , Medula Óssea/imunologia , Imunidade Inata , Imunidade nas Mucosas , Células Matadoras Naturais/imunologia , Macaca mulatta , Proteínas Mitocondriais/metabolismo , Monócitos/imunologia , Linfócitos T/imunologia , Transcriptoma , Fator de Crescimento Transformador beta/metabolismo , Replicação Viral
4.
Nature ; 618(7967): 992-999, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37316666

RESUMO

In the ongoing debates about eukaryogenesis-the series of evolutionary events leading to the emergence of the eukaryotic cell from prokaryotic ancestors-members of the Asgard archaea play a key part as the closest archaeal relatives of eukaryotes1. However, the nature and phylogenetic identity of the last common ancestor of Asgard archaea and eukaryotes remain unresolved2-4. Here we analyse distinct phylogenetic marker datasets of an expanded genomic sampling of Asgard archaea and evaluate competing evolutionary scenarios using state-of-the-art phylogenomic approaches. We find that eukaryotes are placed, with high confidence, as a well-nested clade within Asgard archaea and as a sister lineage to Hodarchaeales, a newly proposed order within Heimdallarchaeia. Using sophisticated gene tree and species tree reconciliation approaches, we show that analogous to the evolution of eukaryotic genomes, genome evolution in Asgard archaea involved significantly more gene duplication and fewer gene loss events compared with other archaea. Finally, we infer that the last common ancestor of Asgard archaea was probably a thermophilic chemolithotroph and that the lineage from which eukaryotes evolved adapted to mesophilic conditions and acquired the genetic potential to support a heterotrophic lifestyle. Our work provides key insights into the prokaryote-to-eukaryote transition and a platform for better understanding the emergence of cellular complexity in eukaryotic cells.


Assuntos
Archaea , Eucariotos , Filogenia , Archaea/classificação , Archaea/citologia , Archaea/genética , Eucariotos/classificação , Eucariotos/citologia , Eucariotos/genética , Células Eucarióticas/classificação , Células Eucarióticas/citologia , Células Procarióticas/classificação , Células Procarióticas/citologia , Conjuntos de Dados como Assunto , Duplicação Gênica , Evolução Molecular
5.
Cell ; 155(3): 531-9, 2013 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-24243013

RESUMO

The global diversity of HIV-1 represents a critical challenge facing HIV-1 vaccine development. HIV-1 mosaic antigens are bioinformatically optimized immunogens designed for improved coverage of HIV-1 diversity. However, the protective efficacy of such global HIV-1 vaccine antigens has not previously been evaluated. Here, we demonstrate the capacity of bivalent HIV-1 mosaic antigens to protect rhesus monkeys against acquisition of infection following heterologous challenges with the difficult-to-neutralize simian-human immunodeficiency virus SHIV-SF162P3. Adenovirus/poxvirus and adenovirus/adenovirus vector-based vaccines expressing HIV-1 mosaic Env, Gag, and Pol afforded a significant reduction in the per-exposure acquisition risk following repetitive, intrarectal SHIV-SF162P3 challenges. Protection against acquisition of infection correlated with vaccine-elicited binding, neutralizing, and functional nonneutralizing antibodies, suggesting that the coordinated activity of multiple antibody functions may contribute to protection against difficult-to-neutralize viruses. These data demonstrate the protective efficacy of HIV-1 mosaic antigens and suggest a potential strategy for the development of a global HIV-1 vaccine. PAPERCLIP:


Assuntos
Vacinas contra a AIDS/imunologia , HIV-1 , Animais , Formação de Anticorpos , Feminino , Antígenos HIV/imunologia , Proteínas do Vírus da Imunodeficiência Humana/imunologia , Imunidade Celular , Macaca mulatta , Masculino , Dados de Sequência Molecular , Organismos Livres de Patógenos Específicos
6.
Proc Natl Acad Sci U S A ; 121(30): e2404164121, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39012823

RESUMO

The development of advanced neural modulation techniques is crucial to neuroscience research and neuroengineering applications. Recently, optical-based, nongenetic modulation approaches have been actively investigated to remotely interrogate the nervous system with high precision. Here, we show that a thin-film, silicon (Si)-based diode device is capable to bidirectionally regulate in vitro and in vivo neural activities upon adjusted illumination. When exposed to high-power and short-pulsed light, the Si diode generates photothermal effects, evoking neuron depolarization and enhancing intracellular calcium dynamics. Conversely, low-power and long-pulsed light on the Si diode hyperpolarizes neurons and reduces calcium activities. Furthermore, the Si diode film mounted on the brain of living mice can activate or suppress cortical activities under varied irradiation conditions. The presented material and device strategies reveal an innovated optoelectronic interface for precise neural modulations.


Assuntos
Neurônios , Optogenética , Silício , Animais , Silício/química , Neurônios/fisiologia , Camundongos , Optogenética/métodos , Cálcio/metabolismo , Luz , Encéfalo/fisiologia
7.
Genes Dev ; 33(1-2): 90-102, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30567997

RESUMO

Piwi-interacting RNAs (piRNAs) engage Piwi proteins to suppress transposons and nonself nucleic acids and maintain genome integrity and are essential for fertility in a variety of organisms. In Caenorhabditis elegans, most piRNA precursors are transcribed from two genomic clusters that contain thousands of individual piRNA transcription units. While a few genes have been shown to be required for piRNA biogenesis, the mechanism of piRNA transcription remains elusive. Here we used functional proteomics approaches to identify an upstream sequence transcription complex (USTC) that is essential for piRNA biogenesis. The USTC contains piRNA silencing-defective 1 (PRDE-1), SNPC-4, twenty-one-U fouled-up 4 (TOFU-4), and TOFU-5. The USTC forms unique piRNA foci in germline nuclei and coats the piRNA cluster genomic loci. USTC factors associate with the Ruby motif just upstream of type I piRNA genes. USTC factors are also mutually dependent for binding to the piRNA clusters and forming the piRNA foci. Interestingly, USTC components bind differentially to piRNAs in the clusters and other noncoding RNA genes. These results reveal the USTC as a striking example of the repurposing of a general transcription factor complex to aid in genome defense against transposons.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Regulação da Expressão Gênica/genética , RNA Interferente Pequeno/genética , Motivos de Aminoácidos , Animais , Proteínas de Caenorhabditis elegans/genética , Genoma Helmíntico/genética , Ligação Proteica , Proteômica , RNA Interferente Pequeno/biossíntese
8.
Plant Cell ; 35(11): 4002-4019, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37648256

RESUMO

Heading date (flowering time), which greatly influences regional and seasonal adaptability in rice (Oryza sativa), is regulated by many genes in different photoperiod pathways. Here, we characterized a heading date gene, Early heading date 5 (Ehd5), using a modified bulked segregant analysis method. The ehd5 mutant showed late flowering under both short-day and long-day conditions, as well as reduced yield, compared to the wild type. Ehd5, which encodes a WD40 domain-containing protein, is induced by light and follows a circadian rhythm expression pattern. Transcriptome analysis revealed that Ehd5 acts upstream of the flowering genes Early heading date 1 (Ehd1), RICE FLOWERING LOCUS T 1 (RFT1), and Heading date 3a (Hd3a). Functional analysis showed that Ehd5 directly interacts with Rice outermost cell-specific gene 4 (Roc4) and Grain number, plant height, and heading date 8 (Ghd8), which might affect the formation of Ghd7-Ghd8 complexes, resulting in increased expression of Ehd1, Hd3a, and RFT1. In a nutshell, these results demonstrate that Ehd5 functions as a positive regulator of rice flowering and provide insight into the molecular mechanisms underlying heading date.


Assuntos
Flores , Oryza , Ritmo Circadiano , Flores/genética , Flores/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Oryza/genética , Oryza/metabolismo , Fotoperíodo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Repetições WD40/genética
9.
Nature ; 578(7795): 425-431, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32051592

RESUMO

Bacteriophages typically have small genomes1 and depend on their bacterial hosts for replication2. Here we sequenced DNA from diverse ecosystems and found hundreds of phage genomes with lengths of more than 200 kilobases (kb), including a genome of 735 kb, which is-to our knowledge-the largest phage genome to be described to date. Thirty-five genomes were manually curated to completion (circular and no gaps). Expanded genetic repertoires include diverse and previously undescribed CRISPR-Cas systems, transfer RNAs (tRNAs), tRNA synthetases, tRNA-modification enzymes, translation-initiation and elongation factors, and ribosomal proteins. The CRISPR-Cas systems of phages have the capacity to silence host transcription factors and translational genes, potentially as part of a larger interaction network that intercepts translation to redirect biosynthesis to phage-encoded functions. In addition, some phages may repurpose bacterial CRISPR-Cas systems to eliminate competing phages. We phylogenetically define the major clades of huge phages from human and other animal microbiomes, as well as from oceans, lakes, sediments, soils and the built environment. We conclude that the large gene inventories of huge phages reflect a conserved biological strategy, and that the phages are distributed across a broad bacterial host range and across Earth's ecosystems.


Assuntos
Bactérias/virologia , Bacteriófagos/classificação , Bacteriófagos/genética , Planeta Terra , Ecossistema , Genoma Viral/genética , Filogenia , Aminoacil-tRNA Sintetases/genética , Animais , Bactérias/genética , Bacteriófagos/isolamento & purificação , Bacteriófagos/metabolismo , Biodiversidade , Sistemas CRISPR-Cas/genética , Evolução Molecular , Regulação Bacteriana da Expressão Gênica , Regulação Viral da Expressão Gênica , Especificidade de Hospedeiro , Humanos , Lagos/virologia , Anotação de Sequência Molecular , Oceanos e Mares , Prófagos/genética , Biossíntese de Proteínas , RNA de Transferência/genética , Proteínas Ribossômicas/genética , Água do Mar/virologia , Microbiologia do Solo , Transcrição Gênica
10.
Nucleic Acids Res ; 52(D1): D762-D769, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37962425

RESUMO

The Reference Sequence (RefSeq) project at the National Center for Biotechnology Information (NCBI) contains over 315 000 bacterial and archaeal genomes and 236 million proteins with up-to-date and consistent annotation. In the past 3 years, we have expanded the diversity of the RefSeq collection by including the best quality metagenome-assembled genomes (MAGs) submitted to INSDC (DDBJ, ENA and GenBank), while maintaining its quality by adding validation checks. Assemblies are now more stringently evaluated for contamination and for completeness of annotation prior to acceptance into RefSeq. MAGs now account for over 17000 assemblies in RefSeq, split over 165 orders and 362 families. Changes in the Prokaryotic Genome Annotation Pipeline (PGAP), which is used to annotate nearly all RefSeq assemblies include better detection of protein-coding genes. Nearly 83% of RefSeq proteins are now named by a curated Protein Family Model, a 4.7% increase in the past three years ago. In addition to literature citations, Enzyme Commission numbers, and gene symbols, Gene Ontology terms are now assigned to 48% of RefSeq proteins, allowing for easier multi-genome comparison. RefSeq is found at https://www.ncbi.nlm.nih.gov/refseq/. PGAP is available as a stand-alone tool able to produce GenBank-ready files at https://github.com/ncbi/pgap.


Assuntos
Archaea , Bactérias , Bases de Dados de Ácidos Nucleicos , Metagenoma , Archaea/genética , Bactérias/genética , Bases de Dados de Ácidos Nucleicos/normas , Bases de Dados de Ácidos Nucleicos/tendências , Genoma Arqueal/genética , Genoma Bacteriano/genética , Internet , Anotação de Sequência Molecular , Proteínas/genética
11.
Proc Natl Acad Sci U S A ; 120(31): e2302938120, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37487095

RESUMO

Neutrophils are the primary cell type involved in lung ischemia-reperfusion injury (IRI), which remains a frequent and morbid complication after organ transplantation. Endogenous lipid mediators that become activated during acute inflammation-resolution have gained increasing recognition for their protective role(s) in promoting the restoration of homeostasis, but their influence on early immune responses following transplantation remains to be uncovered. Resolvin D1, 7S,8R,17S-trihydroxy-4Z,9E,11E,13Z,15E,19Z-docosahexaenoic acid (RvD1), is a potent stereoselective mediator that exhibits proresolving and anti-inflammatory actions in the setting of tissue injury. Here, using metabololipidomics, we demonstrate that endogenous proresolving mediators including RvD1 are increased in human and murine lung grafts immediately following transplantation. In mouse grafts, we observe lipid mediator class switching early after reperfusion. We use intravital two-photon microscopy to reveal that RvD1 treatment significantly limits early neutrophil infiltration and swarming, thereby ameliorating early graft dysfunction in transplanted syngeneic lungs subjected to severe IRI. Through integrated analysis of single-cell RNA sequencing data of donor and recipient immune cells from lung grafts, we identify transcriptomic changes induced by RvD1. These results support a role for RvD1 as a potent modality for preventing early neutrophil-mediated tissue damage after lung IRI that may be therapeutic in the clinics.


Assuntos
Ácidos Docosa-Hexaenoicos , Transplante de Órgãos , Humanos , Animais , Camundongos , Neutrófilos , Pulmão
12.
Mol Biol Evol ; 41(8)2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39041196

RESUMO

Cyanobacteriota, the sole prokaryotes capable of oxygenic photosynthesis (OxyP), occupy a unique and pivotal role in Earth's history. While the notion that OxyP may have originated from Cyanobacteriota is widely accepted, its early evolution remains elusive. Here, by using both metagenomics and metatranscriptomics, we explore 36 metagenome-assembled genomes from hot spring ecosystems, belonging to two deep-branching cyanobacterial orders: Thermostichales and Gloeomargaritales. Functional investigation reveals that Thermostichales encode the crucial thylakoid membrane biogenesis protein, vesicle-inducing protein in plastids 1 (Vipp1). Based on the phylogenetic results, we infer that the evolution of the thylakoid membrane predates the divergence of Thermostichales from other cyanobacterial groups and that Thermostichales may be the most ancient lineage known to date to have inherited this feature from their common ancestor. Apart from OxyP, both lineages are potentially capable of sulfide-driven AnoxyP by linking sulfide oxidation to the photosynthetic electron transport chain. Unexpectedly, this AnoxyP capacity appears to be an acquired feature, as the key gene sqr was horizontally transferred from later-evolved cyanobacterial lineages. The presence of two D1 protein variants in Thermostichales suggests the functional flexibility of photosystems, ensuring their survival in fluctuating redox environments. Furthermore, all MAGs feature streamlined phycobilisomes with a preference for capturing longer-wavelength light, implying a unique evolutionary trajectory. Collectively, these results reveal the photosynthetic flexibility in these early-diverging cyanobacterial lineages, shedding new light on the early evolution of Cyanobacteriota and their photosynthetic processes.


Assuntos
Cianobactérias , Fotossíntese , Fotossíntese/genética , Cianobactérias/genética , Cianobactérias/metabolismo , Evolução Biológica , Filogenia , Oxigênio/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Evolução Molecular
13.
Proc Natl Acad Sci U S A ; 119(10): e2111537119, 2022 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-35238643

RESUMO

Ischemia reperfusion injury represents a common pathological condition that is triggered by the release of endogenous ligands. While neutrophils are known to play a critical role in its pathogenesis, the tissue-specific spatiotemporal regulation of ischemia-reperfusion injury is not understood. Here, using oxidative lipidomics and intravital imaging of transplanted mouse lungs that are subjected to severe ischemia reperfusion injury, we discovered that necroptosis, a nonapoptotic form of cell death, triggers the recruitment of neutrophils. During the initial stages of inflammation, neutrophils traffic predominantly to subpleural vessels, where their aggregation is directed by chemoattractants produced by nonclassical monocytes that are spatially restricted in this vascular compartment. Subsequent neutrophilic disruption of capillaries resulting in vascular leakage is associated with impaired graft function. We found that TLR4 signaling in vascular endothelial cells and downstream NADPH oxidase 4 expression mediate the arrest of neutrophils, a step upstream of their extravasation. Neutrophil extracellular traps formed in injured lungs and their disruption with DNase prevented vascular leakage and ameliorated primary graft dysfunction. Thus, we have uncovered mechanisms that regulate the initial recruitment of neutrophils to injured lungs, which result in selective damage to subpleural pulmonary vessels and primary graft dysfunction. Our findings could lead to the development of new therapeutics that protect lungs from ischemia reperfusion injury.


Assuntos
Endotélio Vascular/metabolismo , Pulmão/metabolismo , Necroptose , Infiltração de Neutrófilos , Neutrófilos/metabolismo , Traumatismo por Reperfusão/metabolismo , Animais , Endotélio Vascular/lesões , Humanos , Pulmão/irrigação sanguínea , Camundongos , Camundongos Knockout , Traumatismo por Reperfusão/genética , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo
14.
BMC Genomics ; 25(1): 584, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862928

RESUMO

MOTIVATION: The rational modelling of the relationship among drugs, targets and diseases is crucial for drug retargeting. While significant progress has been made in studying binary relationships, further research is needed to deepen our understanding of ternary relationships. The application of graph neural networks in drug retargeting is increasing, but further research is needed to determine the appropriate modelling method for ternary relationships and how to capture their complex multi-feature structure. RESULTS: The aim of this study was to construct relationships among drug, targets and diseases. To represent the complex relationships among these entities, we used a heterogeneous graph structure. Additionally, we propose a DTD-GNN model that combines graph convolutional networks and graph attention networks to learn feature representations and association information, facilitating a more thorough exploration of the relationships. The experimental results demonstrate that the DTD-GNN model outperforms other graph neural network models in terms of AUC, Precision, and F1-score. The study has important implications for gaining a comprehensive understanding of the relationships between drugs and diseases, as well as for further research and application in exploring the mechanisms of drug-disease interactions. The study reveals these relationships, providing possibilities for innovative therapeutic strategies in medicine.


Assuntos
Reposicionamento de Medicamentos , Redes Neurais de Computação , Reposicionamento de Medicamentos/métodos , Humanos , Algoritmos , Biologia Computacional/métodos
15.
Neurobiol Dis ; : 106635, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39128813

RESUMO

Early-onset epilepsy following ischemic stroke is a severe neurological condition, the pathogenesis of which remains incompletely understood. Recent studies suggest that Neural stem/progenitor cells (NSPCs) play a crucial role in the disease process, yet the precise molecular mechanisms regulating NSPCs have not been thoroughly investigated. This study utilized single-cell transcriptome sequencing and bioinformatics analysis to identify disease-related genes, which were subsequently validated in both in vitro and in vivo experiments. The findings revealed that Hsp90aa1 (heat shock protein 90 kDa alpha, class A member 1), Jun proto-oncogene (JUN), and CC Motif Ligation 2 (Ccl2) constitute an important regulatory axis influencing the migration and differentiation of NSPCs, potentially impacting the onset and progression of early-onset epilepsy post-ischemic stroke. Additionally, the expression of Hsp90aa1 was found to influence the likelihood of seizure occurrence and the severity of brain ischemia.

16.
Am J Transplant ; 24(2): 280-292, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37619922

RESUMO

The presence of bronchus-associated lymphoid tissue (BALT) in donor lungs has been suggested to accelerate graft rejection after lung transplantation. Although chronic smoke exposure can induce BALT formation, the impact of donor cigarette use on alloimmune responses after lung transplantation is not well understood. Here, we show that smoking-induced BALT in mouse donor lungs contains Foxp3+ T cells and undergoes dynamic restructuring after transplantation, including recruitment of recipient-derived leukocytes to areas of pre-existing lymphoid follicles and replacement of graft-resident donor cells. Our findings from mouse and human lung transplant data support the notion that a donor's smoking history does not predispose to acute cellular rejection or prevent the establishment of allograft acceptance with comparable outcomes to nonsmoking donors. Thus, our work indicates that BALT in donor lungs is plastic in nature and may have important implications for modulating proinflammatory or tolerogenic immune responses following transplantation.


Assuntos
Transplante de Pulmão , Tecido Linfoide , Camundongos , Humanos , Animais , Transplante de Pulmão/efeitos adversos , Tolerância Imunológica , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/prevenção & controle , Pulmão , Brônquios , Fumar
17.
Am J Transplant ; 24(8): 1382-1394, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38522826

RESUMO

Neutrophils exacerbate pulmonary ischemia-reperfusion injury (IRI) resulting in poor short and long-term outcomes for lung transplant recipients. Glycolysis powers neutrophil activation, but it remains unclear if neutrophil-specific targeting of this pathway will inhibit IRI. Lipid nanoparticles containing the glycolysis flux inhibitor 2-deoxyglucose (2-DG) were conjugated to neutrophil-specific Ly6G antibodies (NP-Ly6G[2-DG]). Intravenously administered NP-Ly6G(2-DG) to mice exhibited high specificity for circulating neutrophils. NP-Ly6G(2-DG)-treated neutrophils were unable to adapt to hypoglycemic conditions of the lung airspace environment as evident by the loss of demand-induced glycolysis, reductions in glycogen and ATP content, and an increased vulnerability to apoptosis. NP-Ly6G(2-DG) treatment inhibited pulmonary IRI following hilar occlusion and orthotopic lung transplantation. IRI protection was associated with less airspace neutrophil extracellular trap generation, reduced intragraft neutrophilia, and enhanced alveolar macrophage efferocytotic clearance of neutrophils. Collectively, our data show that pharmacologically targeting glycolysis in neutrophils inhibits their activation and survival leading to reduced pulmonary IRI.


Assuntos
Glicólise , Transplante de Pulmão , Camundongos Endogâmicos C57BL , Nanopartículas , Neutrófilos , Traumatismo por Reperfusão , Animais , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/metabolismo , Camundongos , Glicólise/efeitos dos fármacos , Neutrófilos/metabolismo , Neutrófilos/efeitos dos fármacos , Nanopartículas/química , Masculino , Transplante de Pulmão/efeitos adversos , Desoxiglucose/farmacologia , Apoptose/efeitos dos fármacos , Pulmão/patologia , Pulmão/metabolismo , Pulmão/efeitos dos fármacos
18.
Anal Chem ; 96(17): 6523-6527, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38634570

RESUMO

Complete sample digestion is a prerequisite for acquiring high-quality analytical results for geological samples. Closed-vessel acid digestion (bomb) has typically been used for the total digestion of refractory geological samples. However, the long digestion time (4-5 days) and insoluble fluoride complexes still pose challenges for digesting refractory geological samples using this approach. In this study, an efficient and simplified digestion technique combining ultrafine powders from planetary ball milling with bomb digestion was developed for trace element analysis of refractory geological samples: peridotite and granitoid. The method shows two significant improvements compared with previous approaches. (1) By performing dry planetary ultrafine milling, the initial 200 mesh peridotite (<74 µm) could be reduced to 800 mesh (<20 µm) in 6 min at a ball-to-powder mass ratio of approximately 15 using 3 mm tungsten carbide milling balls. (2) Complete peridotite and granitoid dissolution were achieved in approximately 2 h, 60 times faster than what is achievable using previous methods (2 h vs 120 h). Moreover, ultrafine powders effectively suppressed insoluble fluoride formation during bomb digestion. A suite of peridotite and granitoid reference materials were measured to evaluate the stability of this method. This efficient, simple, and reliable sample digestion method could benefit geological, food, environmental, and other fields requiring solid sample decomposition via wet acid, fusion, combustion, or dry ashing.

19.
J Neuroinflammation ; 21(1): 192, 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39095838

RESUMO

BACKGROUND: Type 2 diabetes mellitus (T2D) is associated with an increased risk of cognitive dysfunction. Angiopoietin-like protein 8 (ANGPTL8) is an important regulator in T2D, but the role of ANGPTL8 in diabetes-associated cognitive dysfunction remains unknown. Here, we explored the role of ANGPTL8 in diabetes-associated cognitive dysfunction through its interaction with paired immunoglobulin-like receptor B (PirB) in the central nervous system. METHODS: The levels of ANGPTL8 in type 2 diabetic patients with cognitive dysfunction and control individuals were measured. Mouse models of diabetes-associated cognitive dysfunction were constructed to investigate the role of ANGPTL8 in cognitive function. The cognitive function of the mice was assessed by the Barnes Maze test and the novel object recognition test, and levels of ANGPTL8, synaptic and axonal markers, and pro-inflammatory cytokines were measured. Primary neurons and microglia were treated with recombinant ANGPTL8 protein (rA8), and subsequent changes were examined. In addition, the changes induced by ANGPTL8 were validated after blocking PirB and its downstream pathways. Finally, mice with central nervous system-specific knockout of Angptl8 and PirB-/- mice were generated, and relevant in vivo experiments were performed. RESULTS: Here, we demonstrated that in the diabetic brain, ANGPTL8 was secreted by neurons into the hippocampus, resulting in neuroinflammation and impairment of synaptic plasticity. Moreover, neuron-specific Angptl8 knockout prevented diabetes-associated cognitive dysfunction and neuroinflammation. Mechanistically, ANGPTL8 acted in parallel to neurons and microglia via its receptor PirB, manifesting as downregulation of synaptic and axonal markers in neurons and upregulation of proinflammatory cytokine expression in microglia. In vivo, PirB-/- mice exhibited resistance to ANGPTL8-induced neuroinflammation and synaptic damage. CONCLUSION: Taken together, our findings reveal the role of ANGPTL8 in the pathogenesis of diabetes-associated cognitive dysfunction and identify the ANGPTL8-PirB signaling pathway as a potential target for the management of this condition.


Assuntos
Proteína 8 Semelhante a Angiopoietina , Proteínas Semelhantes a Angiopoietina , Disfunção Cognitiva , Diabetes Mellitus Tipo 2 , Camundongos Knockout , Receptores Imunológicos , Transdução de Sinais , Animais , Camundongos , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/prevenção & controle , Disfunção Cognitiva/etiologia , Transdução de Sinais/fisiologia , Transdução de Sinais/efeitos dos fármacos , Proteínas Semelhantes a Angiopoietina/metabolismo , Proteínas Semelhantes a Angiopoietina/genética , Humanos , Masculino , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Receptores Imunológicos/metabolismo , Receptores Imunológicos/genética , Camundongos Endogâmicos C57BL , Sinapses/metabolismo , Sinapses/patologia , Sinapses/efeitos dos fármacos , Hormônios Peptídicos/metabolismo , Pessoa de Meia-Idade , Feminino
20.
Opt Express ; 32(3): 4427-4435, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38297644

RESUMO

Multimode fiber lasers have become a new platform for investigating nonlinear phenomena since the report on spatiotemporal mode-locking. In this work, the multimode soliton pulsation with a tunable period is achieved in a spatiotemporal mode-locked fiber laser. It demonstrates that the pulsation period drops while increasing the pump power. Moreover, it is found that different transverse modes have the same pulsation period, asynchronous pulsation evolution and different dynamical characteristics through the spatial sampling technique and the dispersive Fourier transform technique. To further verify the experimental results, we numerically investigate the influences of the gain and the loss on the pulsation properties. It is found that within a certain parameter range, the pulsation period drops and rises linearly with the increase of the gain and the loss, respectively. The obtained results contribute to understanding the formation and regulating of soliton pulsations in fiber lasers.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA