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1.
Cell ; 181(2): 219-222, 2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32302564

RESUMO

Mounting evidence indicates that the nervous system plays a central role in cancer pathogenesis. In turn, cancers and cancer therapies can alter nervous system form and function. This Commentary seeks to describe the burgeoning field of "cancer neuroscience" and encourage multidisciplinary collaboration for the study of cancer-nervous system interactions.


Assuntos
Neoplasias/metabolismo , Sistema Nervoso/metabolismo , Humanos , Neurociências
2.
Immunity ; 57(6): 1360-1377.e13, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38821052

RESUMO

Limited infiltration and activity of natural killer (NK) and T cells within the tumor microenvironment (TME) correlate with poor immunotherapy responses. Here, we examined the role of the endonuclease Regnase-1 on NK cell anti-tumor activity. NK cell-specific deletion of Regnase-1 (Reg1ΔNK) augmented cytolytic activity and interferon-gamma (IFN-γ) production in vitro and increased intra-tumoral accumulation of Reg1ΔNK-NK cells in vivo, reducing tumor growth dependent on IFN-γ. Transcriptional changes in Reg1ΔNK-NK cells included elevated IFN-γ expression, cytolytic effectors, and the chemokine receptor CXCR6. IFN-γ induced expression of the CXCR6 ligand CXCL16 on myeloid cells, promoting further recruitment of Reg1ΔNK-NK cells. Mechanistically, Regnase-1 deletion increased its targets, the transcriptional regulators OCT2 and IκBζ, following interleukin (IL)-12 and IL-18 stimulation, and the resulting OCT2-IκBζ-NF-κB complex induced Ifng transcription. Silencing Regnase-1 in human NK cells increased the expression of IFNG and POU2F2. Our findings highlight NK cell dysfunction in the TME and propose that targeting Regnase-1 could augment active NK cell persistence for cancer immunotherapy.


Assuntos
Interferon gama , Células Matadoras Naturais , Microambiente Tumoral , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Animais , Interferon gama/metabolismo , Humanos , Camundongos , Microambiente Tumoral/imunologia , Camundongos Endogâmicos C57BL , Ribonucleases/metabolismo , Ribonucleases/genética , Camundongos Knockout , Transcrição Gênica , Linhagem Celular Tumoral , NF-kappa B/metabolismo
3.
Immunity ; 56(3): 465-467, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36921570

RESUMO

Tissue-immune cell interactions in the periphery are well appreciated but incompletely understood. In this issue of Immunity, Wang et al. demonstrate how the disruption of a lung stromal niche leads to expansion of lung-resident lymphocytes and IFN-γ-driven exacerbation of emphysema.


Assuntos
Pulmão , Linfócitos
4.
Nature ; 631(8021): 601-609, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38987587

RESUMO

Exaggerated airway constriction triggered by repeated exposure to allergen, also called hyperreactivity, is a hallmark of asthma. Whereas vagal sensory neurons are known to function in allergen-induced hyperreactivity1-3, the identity of downstream nodes remains poorly understood. Here we mapped a full allergen circuit from the lung to the brainstem and back to the lung. Repeated exposure of mice to inhaled allergen activated the nuclei of solitary tract (nTS) neurons in a mast cell-, interleukin-4 (IL-4)- and vagal nerve-dependent manner. Single-nucleus RNA sequencing, followed by RNAscope assay at baseline and allergen challenges, showed that a Dbh+ nTS population is preferentially activated. Ablation or chemogenetic inactivation of Dbh+ nTS neurons blunted hyperreactivity whereas chemogenetic activation promoted it. Viral tracing indicated that Dbh+ nTS neurons project to the nucleus ambiguus (NA) and that NA neurons are necessary and sufficient to relay allergen signals to postganglionic neurons that directly drive airway constriction. Delivery of noradrenaline antagonists to the NA blunted hyperreactivity, suggesting noradrenaline as the transmitter between Dbh+ nTS and NA. Together, these findings provide molecular, anatomical and functional definitions of key nodes of a canonical allergen response circuit. This knowledge informs how neural modulation could be used to control allergen-induced airway hyperreactivity.


Assuntos
Alérgenos , Tronco Encefálico , Neurônios , Núcleo Solitário , Nervo Vago , Animais , Camundongos , Alérgenos/imunologia , Masculino , Núcleo Solitário/imunologia , Neurônios/imunologia , Feminino , Tronco Encefálico/imunologia , Pulmão/imunologia , Pulmão/patologia , Pulmão/inervação , Norepinefrina/metabolismo , Interleucina-4/metabolismo , Interleucina-4/imunologia , Mastócitos/imunologia , Asma/imunologia , Hiper-Reatividade Brônquica/imunologia , Hiper-Reatividade Brônquica/fisiopatologia
5.
Immunity ; 51(6): 977-979, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31851903

RESUMO

In this issue of Immunity, Wang et al. identify a developmental transition of neural-immune interactions from postnatal to adult lung. Their findings implicate sympathetic nerve production of dopamine as a contributor to the susceptibility of children to allergen-induced asthmatic responses.


Assuntos
Dopamina , Sons Respiratórios , Adulto , Alérgenos , Criança , Humanos , Inflamação , Sistema Nervoso Simpático
6.
Cell ; 153(4): 773-84, 2013 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-23663777

RESUMO

5-methylcytosine is a major epigenetic modification that is sometimes called "the fifth nucleotide." However, our knowledge of how offspring inherit the DNA methylome from parents is limited. We generated nine single-base resolution DNA methylomes, including zebrafish gametes and early embryos. The oocyte methylome is significantly hypomethylated compared to sperm. Strikingly, the paternal DNA methylation pattern is maintained throughout early embryogenesis. The maternal DNA methylation pattern is maintained until the 16-cell stage. Then, the oocyte methylome is gradually discarded through cell division and is progressively reprogrammed to a pattern similar to that of the sperm methylome. The passive demethylation rate and the de novo methylation rate are similar in the maternal DNA. By the midblastula stage, the embryo's methylome is virtually identical to the sperm methylome. Moreover, inheritance of the sperm methylome facilitates the epigenetic regulation of embryogenesis. Therefore, besides DNA sequences, sperm DNA methylome is also inherited in zebrafish early embryos.


Assuntos
Metilação de DNA , Embrião não Mamífero/metabolismo , Oócitos/metabolismo , Espermatozoides/metabolismo , Peixe-Zebra/embriologia , Peixe-Zebra/genética , 5-Metilcitosina/análise , Animais , Epigênese Genética , Feminino , Células Germinativas/metabolismo , Masculino , Peixe-Zebra/metabolismo
7.
Proc Natl Acad Sci U S A ; 121(6): e2310821121, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38300873

RESUMO

Impaired expression of MHC (major histocompatibility complex) class I in cancers constitutes a major mechanism of immune evasion. It has been well documented that the low level of MHC class I is associated with poor prognosis and resistance to checkpoint blockade therapies. However, there is lmited approaches to specifically induce MHC class I to date. Here, we show an approach for robust and specific induction of MHC class I by targeting an MHC class I transactivator (CITA)/NLRC5, using a CRISPR/Cas9-based gene-specific system, designated TRED-I (Targeted reactivation and demethylation for MHC-I). The TRED-I system specifically recruits a demethylating enzyme and transcriptional activators on the NLRC5 promoter, driving increased MHC class I antigen presentation and accelerated CD8+ T cell activation. Introduction of the TRED-I system in an animal cancer model exhibited tumor-suppressive effects accompanied with increased infiltration and activation of CD8+ T cells. Moreover, this approach boosted the efficacy of checkpoint blockade therapy using anti-PD1 (programmed cell death protein) antibody. Therefore, targeting NLRC5 by this strategy provides an attractive therapeutic approach for cancer.


Assuntos
Genes MHC Classe I , Neoplasias , Animais , Genes MHC Classe I/genética , Antígenos de Histocompatibilidade Classe I , Transativadores/metabolismo , Neoplasias/genética , Desmetilação
8.
Proc Natl Acad Sci U S A ; 120(24): e2218955120, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37279268

RESUMO

Major histocompatibility complex (MHC) class I and II molecules play critical roles in the activation and regulation of adaptive immunity through antigen presentation to CD8+ and CD4+ T cells, respectively. Strict regulation of MHC expression is critical for proper immune responses. CIITA (MHC class II transactivator), an NLR (nucleotide-binding domain, leucine-rich-repeat containing) protein, is a master regulator of MHC class II (MHC-II) gene transcription. Although it has been known that CIITA activity is regulated at the transcriptional and protein levels, the mechanism to determine CIITA protein level has not been elucidated. Here, we show that FBXO11 is a bona fide E3 ligase of CIITA and regulates CIITA protein level through ubiquitination-mediated degradation. A nonbiased proteomic approach for CIITA-binding protein identified FBXO11, a member of the Skp1-Cullin-1-F-box E3 ligase complex, as a binding partner of CIITA but not MHC class I transactivator, NLRC5. The cycloheximide chase assay showed that the half-life of CIITA is mainly regulated by FBXO11 via the ubiquitin-proteasome system. The expression of FBXO11 led to the reduced MHC-II at the promoter activity level, transcriptional level, and surface expression level through downregulation of CIITA. Moreover, human and mouse FBXO11-deficient cells display increased levels of MHC-II and related genes. In normal and cancer tissues, FBXO11 expression level is negatively correlated with MHC-II. Interestingly, the expression of FBXO11, along with CIITA, is associated with prognosis of cancer patients. Therefore, FBXO11 is a critical regulator to determine the level of MHC-II, and its expression may serve as a biomarker for cancer.


Assuntos
Proteínas F-Box , Neoplasias , Animais , Humanos , Camundongos , Proteínas F-Box/genética , Genes MHC da Classe II , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/metabolismo , Antígenos HLA , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias/genética , Proteína-Arginina N-Metiltransferases/genética , Proteína-Arginina N-Metiltransferases/metabolismo , Proteômica , Transativadores/metabolismo , Ubiquitina/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
9.
EMBO J ; 40(5): e107651, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33576058

RESUMO

Defining the pulmonary cell types infected by SARS-CoV-2 and finding ways to prevent subsequent tissue damage are key goals for controlling COVID-19. Recent work establishing a human lung organoid-derived air-liquid interface model permissive to SARS-CoV-2 infection identifies alveolar type II cells as the primary cell type infected, reports an infection-induced interferon response and demonstrates the effectiveness of interferon lambda 1 treatment in dampening lung infection.


Assuntos
Células Epiteliais Alveolares/metabolismo , COVID-19/metabolismo , Modelos Biológicos , Organoides/metabolismo , SARS-CoV-2/fisiologia , Replicação Viral , Células Epiteliais Alveolares/patologia , Células Epiteliais Alveolares/virologia , COVID-19/patologia , Humanos , Organoides/patologia , Organoides/virologia , Tratamento Farmacológico da COVID-19
10.
Nat Immunol ; 14(6): 633-43, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23624555

RESUMO

The differentiation of hematopoietic stem cells into cells of the immune system has been studied extensively in mammals, but the transcriptional circuitry that controls it is still only partially understood. Here, the Immunological Genome Project gene-expression profiles across mouse immune lineages allowed us to systematically analyze these circuits. To analyze this data set we developed Ontogenet, an algorithm for reconstructing lineage-specific regulation from gene-expression profiles across lineages. Using Ontogenet, we found differentiation stage-specific regulators of mouse hematopoiesis and identified many known hematopoietic regulators and 175 previously unknown candidate regulators, as well as their target genes and the cell types in which they act. Among the previously unknown regulators, we emphasize the role of ETV5 in the differentiation of γδ T cells. As the transcriptional programs of human and mouse cells are highly conserved, it is likely that many lessons learned from the mouse model apply to humans.


Assuntos
Algoritmos , Regulação da Expressão Gênica/imunologia , Sistema Imunitário/metabolismo , Transcrição Gênica/imunologia , Animais , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Linhagem da Célula/genética , Linhagem da Célula/imunologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/imunologia , Perfilação da Expressão Gênica , Redes Reguladoras de Genes/imunologia , Humanos , Sistema Imunitário/citologia , Camundongos , Análise de Sequência com Séries de Oligonucleotídeos , Receptores de Antígenos de Linfócitos T gama-delta/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/imunologia , Linfócitos T/imunologia , Linfócitos T/metabolismo , Transativadores/genética , Transativadores/imunologia , Fatores de Transcrição/genética , Fatores de Transcrição/imunologia , Transcriptoma/genética , Transcriptoma/imunologia
11.
J Allergy Clin Immunol ; 153(4): 879-893, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37634890

RESUMO

Type 2 inflammation is characterized by overexpression and heightened activity of type 2 cytokines, mediators, and cells that drive neuroimmune activation and sensitization to previously subthreshold stimuli. The consequences of altered neuroimmune activity differ by tissue type and disease; they include skin inflammation, sensitization to pruritogens, and itch amplification in atopic dermatitis and prurigo nodularis; airway inflammation and/or hyperresponsiveness, loss of expiratory volume, airflow obstruction and increased mucus production in asthma; loss of sense of smell in chronic rhinosinusitis with nasal polyps; and dysphagia in eosinophilic esophagitis. We describe the neuroimmune interactions that underlie the various sensory and autonomic pathologies in type 2 inflammatory diseases and present recent advances in targeted treatment approaches to reduce type 2 inflammation and its associated symptoms in these diseases. Further research is needed to better understand the neuroimmune mechanisms that underlie chronic, sustained inflammation and its related sensory pathologies in diseases associated with type 2 inflammation.


Assuntos
Asma , Dermatite Atópica , Sinusite , Humanos , Inflamação , Prurido/tratamento farmacológico , Sinusite/patologia
12.
Nano Lett ; 24(2): 715-723, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38147540

RESUMO

Solar-driven clean water production is challenged by VOCs (volatile organic compounds), which pose health risks in distilled water. Herein, we developed a Cu/W18O49@Graphene photothermal-photocatalytic material addressing VOCs contamination. Plasmonic coupling between Cu and W18O49 enhances light absorption, and 1-2 layers of graphene encapsulation protects oxygen vacancies within W18O49 while facilitating hot electron extraction, effectively mitigating their ultrafast relaxation. Density functional theory calculations revealed enhanced VOCs adsorption on graphene. These synergies address oxygen vacancy decay in W18O49 and provide more active sites for gas-liquid-solid triphase photocatalytic reactions. Integrated with a three-dimensional floating evaporator substrate, the optimized Cu/W18O49@Graphene material achieved an effective water evaporation rate of 1.41 kg m-2 h-1 (efficiency of 88.6%), exceptional stability (>120 h), and remarkable 99% phenol removal under 1 sun irradiation (1 kW m-2). This work provides a promising solution to mitigate VOCs contamination in solar-driven water evaporation.

13.
Nano Lett ; 24(26): 8151-8161, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38912914

RESUMO

The size of liposomal drugs has been demonstrated to strongly correlate with their pharmacokinetics and pharmacodynamics. While the microfluidic method successfully achieves the production of liposomes with well-controlled sizes across various buffer/lipid flow rate ratio (FRR) settings, any adjustments to the FRR inevitably influence the concentration, encapsulation efficiency (EE), and stability of liposomal drugs. Here we describe a controllable cavitation-on-a-chip (CCC) strategy that facilitates the precise regulation of liposomal drug size at any desired FRR. The CCC-enabled size-specific liposomes exhibited striking differences in uptake and biodistribution behaviors, thereby demonstrating distinct antitumor efficacy in both tumor-bearing animal and melanoma patient-derived organoid (PDO) models. Intriguingly, as the liposome size decreased to approximately 80 nm, the preferential accumulation of liposomal drugs in the liver transitioned to a predominant enrichment in the kidneys. These findings underscore the considerable potential of our CCC approach in influencing the pharmacokinetics and pharmacodynamics of liposomal nanomedicines.


Assuntos
Dispositivos Lab-On-A-Chip , Lipossomos , Lipossomos/química , Animais , Humanos , Camundongos , Distribuição Tecidual , Tamanho da Partícula , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/administração & dosagem , Linhagem Celular Tumoral , Melanoma/tratamento farmacológico , Melanoma/patologia
14.
BMC Genomics ; 25(1): 189, 2024 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-38368357

RESUMO

BACKGROUND: CRISPR-Cas9 technology has advanced in vivo gene therapy for disorders like hemophilia A, notably through the successful targeted incorporation of the F8 gene into the Alb locus in hepatocytes, effectively curing this disorder in mice. However, thoroughly evaluating the safety and specificity of this therapy is essential. Our study introduces a novel methodology to analyze complex insertion sequences at the on-target edited locus, utilizing barcoded long-range PCR, CRISPR RNP-mediated deletion of unedited alleles, magnetic bead-based long amplicon enrichment, and nanopore sequencing. RESULTS: We identified the expected F8 insertions and various fragment combinations resulting from the in vivo linearization of the double-cut plasmid donor. Notably, our research is the first to document insertions exceeding ten kbp. We also found that a small proportion of these insertions were derived from sources other than donor plasmids, including Cas9-sgRNA plasmids, genomic DNA fragments, and LINE-1 elements. CONCLUSIONS: Our study presents a robust method for analyzing the complexity of on-target editing, particularly for in vivo long insertions, where donor template integration can be challenging. This work offers a new tool for quality control in gene editing outcomes and underscores the importance of detailed characterization of edited genomic sequences. Our findings have significant implications for enhancing the safety and effectiveness of CRISPR-Cas9 gene therapy in treating various disorders, including hemophilia A.


Assuntos
Hemofilia A , Sequenciamento por Nanoporos , Camundongos , Animais , Sistemas CRISPR-Cas , RNA Guia de Sistemas CRISPR-Cas , Hemofilia A/genética , Hemofilia A/terapia , Edição de Genes/métodos , DNA
15.
J Am Chem Soc ; 146(1): 723-732, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38116993

RESUMO

Despite the current progress achieved in asymmetric hydroacylations, highly enantioselective catalytic addition of unfunctionalized aldehydes to internal alkenes remains an unsolved challenge. Here, using a coordination-assisted strategy, we developed a rhodium-catalyzed regio- and enantioselective addition of unfunctionalized aldehydes to internal alkenes such as enamides and ß,γ-unsaturated amides. Valuable α-amino ketones and 1,4-dicarbonyl compounds were directly obtained with high enantioselectivity from readily available materials.

16.
Mol Biol Evol ; 40(9)2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37561011

RESUMO

The black rhinoceros (Diceros bicornis L.) is a critically endangered species historically distributed across sub-Saharan Africa. Hunting and habitat disturbance have diminished both its numbers and distribution since the 19th century, but a poaching crisis in the late 20th century drove them to the brink of extinction. Genetic and genomic assessments can greatly increase our knowledge of the species and inform management strategies. However, when a species has been severely reduced, with the extirpation and artificial admixture of several populations, it is extremely challenging to obtain an accurate understanding of historic population structure and evolutionary history from extant samples. Therefore, we generated and analyzed whole genomes from 63 black rhinoceros museum specimens collected between 1775 and 1981. Results showed that the black rhinoceros could be genetically structured into six major historic populations (Central Africa, East Africa, Northwestern Africa, Northeastern Africa, Ruvuma, and Southern Africa) within which were nested four further subpopulations (Maasailand, southwestern, eastern rift, and northern rift), largely mirroring geography, with a punctuated north-south cline. However, we detected varying degrees of admixture among groups and found that several geographical barriers, most prominently the Zambezi River, drove population discontinuities. Genomic diversity was high in the middle of the range and decayed toward the periphery. This comprehensive historic portrait also allowed us to ascertain the ancestry of 20 resequenced genomes from extant populations. Lastly, using insights gained from this unique temporal data set, we suggest management strategies, some of which require urgent implementation, for the conservation of the remaining black rhinoceros diversity.


Assuntos
Evolução Biológica , Perissodáctilos , Animais , África Oriental , África Subsaariana , Perissodáctilos/genética , Espécies em Perigo de Extinção
17.
Am J Hum Genet ; 108(10): 1964-1980, 2021 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-34547244

RESUMO

Congenital diaphragmatic hernia (CDH) is a severe congenital anomaly that is often accompanied by other anomalies. Although the role of genetics in the pathogenesis of CDH has been established, only a small number of disease-associated genes have been identified. To further investigate the genetics of CDH, we analyzed de novo coding variants in 827 proband-parent trios and confirmed an overall significant enrichment of damaging de novo variants, especially in constrained genes. We identified LONP1 (lon peptidase 1, mitochondrial) and ALYREF (Aly/REF export factor) as candidate CDH-associated genes on the basis of de novo variants at a false discovery rate below 0.05. We also performed ultra-rare variant association analyses in 748 affected individuals and 11,220 ancestry-matched population control individuals and identified LONP1 as a risk gene contributing to CDH through both de novo and ultra-rare inherited largely heterozygous variants clustered in the core of the domains and segregating with CDH in affected familial individuals. Approximately 3% of our CDH cohort who are heterozygous with ultra-rare predicted damaging variants in LONP1 have a range of clinical phenotypes, including other anomalies in some individuals and higher mortality and requirement for extracorporeal membrane oxygenation. Mice with lung epithelium-specific deletion of Lonp1 die immediately after birth, most likely because of the observed severe reduction of lung growth, a known contributor to the high mortality in humans. Our findings of both de novo and inherited rare variants in the same gene may have implications in the design and analysis for other genetic studies of congenital anomalies.


Assuntos
Proteases Dependentes de ATP/genética , Proteases Dependentes de ATP/fisiologia , Anormalidades Craniofaciais/genética , Variações do Número de Cópias de DNA , Anormalidades do Olho/genética , Transtornos do Crescimento/genética , Hérnias Diafragmáticas Congênitas/genética , Luxação Congênita de Quadril/genética , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/fisiologia , Mutação de Sentido Incorreto , Osteocondrodisplasias/genética , Anormalidades Dentárias/genética , Animais , Estudos de Casos e Controles , Estudos de Coortes , Anormalidades Craniofaciais/patologia , Anormalidades do Olho/patologia , Feminino , Transtornos do Crescimento/patologia , Hérnias Diafragmáticas Congênitas/patologia , Luxação Congênita de Quadril/patologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Osteocondrodisplasias/patologia , Linhagem , Anormalidades Dentárias/patologia
18.
Development ; 148(9)2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33969874

RESUMO

During heart development, epicardial cells residing within the outer layer undergo epithelial-mesenchymal transition (EMT) and migrate into the underlying myocardium to support organ growth and morphogenesis. Disruption of epicardial EMT results in embryonic lethality, yet its regulation is poorly understood. Here, we report epicardial EMT within the mesothelial layer of the mouse embryonic heart at ultra-high resolution using scanning electron microscopy combined with immunofluorescence analyses. We identified morphologically active EMT regions that associated with key components of the extracellular matrix, including the basement membrane-associated proteoglycan agrin. Deletion of agrin resulted in impaired EMT and compromised development of the epicardium, accompanied by downregulation of Wilms' tumor 1. Agrin enhanced EMT in human embryonic stem cell-derived epicardial-like cells by decreasing ß-catenin and promoting pFAK localization at focal adhesions, and promoted the aggregation of dystroglycan within the Golgi apparatus in murine epicardial cells. Loss of agrin resulted in dispersal of dystroglycan in vivo, disrupting basement membrane integrity and impairing EMT. Our results provide new insights into the role of the extracellular matrix in heart development and implicate agrin as a crucial regulator of epicardial EMT.


Assuntos
Agrina/metabolismo , Transição Epitelial-Mesenquimal/fisiologia , Proteínas da Matriz Extracelular/metabolismo , Coração/embriologia , Coração/crescimento & desenvolvimento , Organogênese/fisiologia , Animais , Feminino , Heterogeneidade Genética , Complexo de Golgi , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miocárdio/metabolismo , Pericárdio/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
19.
Development ; 148(3)2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33462113

RESUMO

Macrophages are components of the innate immune system with key roles in tissue inflammation and repair. It is now evident that macrophages also support organogenesis, but few studies have characterized their identity, ontogeny and function during heart development. Here, we show that the distribution and prevalence of resident macrophages in the subepicardial compartment of the developing heart coincides with the emergence of new lymphatics, and that macrophages interact closely with the nascent lymphatic capillaries. Consequently, global macrophage deficiency led to extensive vessel disruption, with mutant hearts exhibiting shortened and mis-patterned lymphatics. The origin of cardiac macrophages was linked to the yolk sac and foetal liver. Moreover, the Cx3cr1+ myeloid lineage was found to play essential functions in the remodelling of the lymphatic endothelium. Mechanistically, macrophage hyaluronan was required for lymphatic sprouting by mediating direct macrophage-lymphatic endothelial cell interactions. Together, these findings reveal insight into the role of macrophages as indispensable mediators of lymphatic growth during the development of the mammalian cardiac vasculature.


Assuntos
Coração/crescimento & desenvolvimento , Vasos Linfáticos , Macrófagos/metabolismo , Animais , Receptor 1 de Quimiocina CX3C/genética , Adesão Celular , Linhagem Celular , Células Endoteliais , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Introdução de Genes , Humanos , Inflamação , Linfangiogênese , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Organogênese/genética , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/genética , Saco Vitelino
20.
Small ; : e2401675, 2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38644329

RESUMO

Anodes with high capacity and long lifespan play an important role in the advanced batteries. However, none of the existing anodes can meet these two requirements simultaneously. Lithium (Li)-graphite composite anode presents great potential in balancing these two requirements. Herein, the working mechanism of Li-graphite composite anode is comprehensively investigated. The capacity decay features of the composite anode are different from those of Li ion intercalation in Li ion batteries and Li metal deposition in Li metal batteries. An intercalation and conversion hybrid storage mechanism are proposed by analyzing the capacity decay ratios in the composite anode with different initial specific capacities. The capacity decay models can be divided into four stages including Capacity Retention Stage, Relatively Independent Operation Stage, Intercalation & Conversion Coupling Stage, Pure Li Intercalation Stage. When the specific capacity is between 340 and 450 mAh g-1, its capacity decay ratio is between that of pure intercalation and conversion model. These results intensify the comprehensive understandings on the working principles in Li-graphite composite anode and present novel insights in the design of high-capacity and long-lifespan anode materials for the next-generation batteries.

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