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Deregulation of the TH17 subset of helper T cells is closely linked with immunological disorders and inflammatory diseases. However, the mechanism by which TH17 cells are regulated remains elusive. Here we found that the phosphatase DUSP2 (PAC1) negatively regulated the development of TH17 cells. DUSP2 was directly associated with the signal transducer and transcription activator STAT3 and attenuated its activity through dephosphorylation of STAT3 at Tyr705 and Ser727. DUSP2-deficient mice exhibited severe susceptibility to experimental colitis, with enhanced differentiation of TH17 cells and secretion of proinflammatory cytokines. In clinical patients with ulcerative colitis, DUSP2 was downregulated by DNA methylation and was not induced during T cell activation. Our data demonstrate that DUSP2 is a true STAT3 phosphatase that modulates the development of TH17 cells in the autoimmune response and inflammation.
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Diferenciação Celular/imunologia , Fosfatase 2 de Especificidade Dupla/imunologia , Fator de Transcrição STAT3/imunologia , Células Th17/imunologia , Animais , Células Cultivadas , Colite/induzido quimicamente , Colite/genética , Colite/imunologia , Colite Ulcerativa/genética , Colite Ulcerativa/imunologia , Colite Ulcerativa/metabolismo , Citocinas/imunologia , Citocinas/metabolismo , Metilação de DNA/imunologia , Sulfato de Dextrana , Fosfatase 2 de Especificidade Dupla/deficiência , Fosfatase 2 de Especificidade Dupla/genética , Regulação da Expressão Gênica/imunologia , Células HEK293 , Humanos , Immunoblotting , Mediadores da Inflamação/imunologia , Mediadores da Inflamação/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosforilação/imunologia , Ligação Proteica/imunologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição STAT3/metabolismo , Células Th17/metabolismo , Tirosina/imunologia , Tirosina/metabolismoRESUMO
PTEN is one of the most frequently mutated genes in malignancies and acts as a powerful tumor suppressor. Tumorigenesis is involved in multiple and complex processes including initiation, invasion, and metastasis. The complexity of PTEN function is partially attributed to PTEN family members such as PTENα and PTENß. Here, we report the identification of PTENε (also named as PTEN5), a novel N-terminal-extended PTEN isoform that suppresses tumor invasion and metastasis. We show that the translation of PTENε/PTEN5 is initiated from the CUG816 codon within the 5'UTR region of PTEN mRNA. PTENε/PTEN5 mainly localizes in the cell membrane and physically associates with and dephosphorylates VASP and ACTR2, which govern filopodia formation and cell motility. We found that endogenous depletion of PTENε/PTEN5 promotes filopodia formation and enhances the metastasis capacity of tumor cells. Overall, we identify a new isoform of PTEN with distinct subcellular localization and molecular function compared to the known members of the PTEN family. These findings advance our current understanding of the importance and diversity of PTEN functions.
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PTEN Fosfo-Hidrolase/metabolismo , Pseudópodes/metabolismo , Animais , Western Blotting , Carcinogênese/metabolismo , Transformação Celular Neoplásica/metabolismo , Humanos , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal , PTEN Fosfo-Hidrolase/genética , Reação em Cadeia da Polimerase em Tempo RealRESUMO
Neutrophils are a major component of immune defense and are recruited through neutrophil chemotaxis in response to invading pathogens. However, the molecular mechanism that controls neutrophil chemotaxis remains unclear. Here, we report that PTENα, the first isoform identified in the PTEN family, regulates neutrophil deformability and promotes chemotaxis of neutrophils. A high level of PTENα is detected in neutrophils and lymphoreticular tissues. Homozygous deletion of PTENα impairs chemoattractant-induced migration of neutrophils. We show that PTENα physically interacts with cell membrane cross-linker moesin through its FERM domain and dephosphorylates moesin at Thr558, which disrupts the association of filamentous actin with the plasma membrane and subsequently induces morphologic changes in neutrophil pseudopodia. These results demonstrate that PTENα acts as a phosphatase of moesin and modulates neutrophil-mediated host immune defense. We propose that PTENα signaling is a potential target for the treatment of infections and immune diseases.
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Quimiotaxia de Leucócito/fisiologia , Neutrófilos/metabolismo , PTEN Fosfo-Hidrolase/metabolismo , Animais , Feminino , Masculino , Camundongos , Camundongos Knockout , Proteínas dos Microfilamentos/imunologia , Proteínas dos Microfilamentos/metabolismo , Neutrófilos/imunologia , PTEN Fosfo-Hidrolase/imunologiaRESUMO
BACKGROUND: Since the outbreak of coronavirus disease 2019 in December 2019, more than 8 million cases have occurred worldwide as of June 16, 2020. However, it is important to distinguish COVID-19 from other respiratory infectious diseases, such as influenza. Here, we comparatively described the clinical characteristics of children with COVID-19 and paediatric patients with influenza. METHODS: In this retrospective, single-centre study, we reviewed the electronic medical records of 585 paediatric patients with COVID-19 or influenza in Wuhan Children's Hospital, China. Clinical and epidemiological characteristics, laboratory findings, and clinical outcomes were comparatively analysed. RESULTS: The median ages were 6.96 years (IQR, 2-10.81) for children with confirmed COVID-19, 2.67 years (IQR, 1.03-15.25) for those with influenza A and 3.67 years (IQR, 1.62-5.54) for those with influenza B. Fever was a symptom in 84 (34.7%) COVID-19 cases, 132 (70.21%) influenza A cases and 111 (74.50%) influenza B cases. The median length of stay (LOS) was 11 (8-15) days for paediatric COVID-19 patients, 4 (3-6) days for influenza A patients and 5 (3-6) days for influenza B patients. Twenty-six (13.98%) influenza A patients and 18 (12.59%) influenza B patients presented with decreased white blood cell counts, while 13 (5.33%) COVID-19 patients presented with decreased white blood cell counts. Eight (3.28%) COVID-19 patients, 23 (12.71%) influenza A patients and 21 (14.79%) influenza B patients experienced lymphocytopenia. Acute cardiac injury occurred in 18 (7.29%) COVID-19 patients, while 37 (19.68%) influenza A and 27 (18.12%) influenza B patients had acute cardiac injury. CONCLUSION: In this study, the illnesses of children with COVID-19 were demonstrated to be less severe than those of paediatric patients with influenza, and COVID-19 patients had milder illness and fewer complications.
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Tratamento Farmacológico da COVID-19 , COVID-19/etiologia , Influenza Humana/tratamento farmacológico , Influenza Humana/etiologia , Adolescente , COVID-19/epidemiologia , Criança , Criança Hospitalizada , Pré-Escolar , China/epidemiologia , Comorbidade , Feminino , Febre/epidemiologia , Hospitais Pediátricos , Humanos , Lactente , Influenza Humana/epidemiologia , Tempo de Internação , Linfopenia/epidemiologia , Linfopenia/virologia , Masculino , Síndrome do Desconforto Respiratório/tratamento farmacológico , Síndrome do Desconforto Respiratório/epidemiologia , Síndrome do Desconforto Respiratório/etiologia , Síndrome do Desconforto Respiratório/virologia , Estudos RetrospectivosRESUMO
The number of coronavirus disease 2019 (COVID-19) cases has exceeded 10 million. However, little is known about the epidemiology and clinical characteristics of COVID-19 infants. We collected medical information of 46 confirmed patients (<1 year old) and retrospectively analyzed epidemiological history, clinical symptoms, and laboratory test results. The median age was 5 (interquartile range, 2-7) months. Sixteen cases had fever and 27 cases had cough. Moderate disease was present in 40 cases and cardiac injury occurred in 38 cases, following by liver dysfunction in 20 cases and lymphocytosis in no cases. Of all infant patients, 2 received invasive mechanical ventilation and 1 died with multiple organ dysfunction syndrome.
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Infecções por Coronavirus/epidemiologia , Pneumonia Viral/epidemiologia , Fatores Etários , Betacoronavirus/isolamento & purificação , COVID-19 , China/epidemiologia , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/terapia , Tosse/terapia , Tosse/virologia , Feminino , Febre/terapia , Febre/virologia , Humanos , Lactente , Masculino , Insuficiência de Múltiplos Órgãos/terapia , Insuficiência de Múltiplos Órgãos/virologia , Pandemias , Pneumonia Viral/diagnóstico , Pneumonia Viral/terapia , Estudos Retrospectivos , SARS-CoV-2 , Resultado do TratamentoRESUMO
While nanoparticles exert bactericidal effects through the generation of reactive oxygen species (ROS), the processes of the internalization of and the direct physical damage caused by iron oxide nanoparticles are not completely clear. We hypothesize that direct physical or mechanical damage of the cell membrane and cytoplasmic integrity by nanoparticles is another major cause of bacterial death besides ROS. The aim of this study is to investigate the process of the internalization of iron oxide nanoparticles, and to evaluate the effect of direct physical or mechanical damage on bacterial cell growth and death. The results demonstrate that iron oxide nanoparticles not only inhibited E. coli cell growth, but also caused bacterial cell death. Iron oxide nanoparticles produced significantly elevated ROS levels in bacteria. Transmission electronic microscopy demonstrated that iron oxide nanoparticles were internalized into and condensed the cytoplasm. Strikingly, we observed that the internalized nanoparticles caused intracellular vacuole formation, instead of simply adsorbing thereon; and formed clusters on the bacterial surface and tore up the outer cell membrane to release cytoplasm. This is the first time that the exact process of the internalization of iron oxide nanoparticles has been observed. We speculate that the intracellular vacuole formation and direct physical or mechanical damage caused by the iron oxide nanoparticles caused the bactericidal effect, along with the effects of ROS.
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Antibacterianos/metabolismo , Escherichia coli/metabolismo , Compostos Férricos/metabolismo , Nanopartículas/metabolismo , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/ultraestrutura , Compostos Férricos/farmacologia , Viabilidade Microbiana/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismoRESUMO
We describe a species of Hoolock gibbon (Primates: Hylobatidae) that is new to science from eastern Myanmar and southwestern China. The genus of hoolock gibbons comprises two previously described living species, the western (Hoolock hoolock) and eastern hoolock (H. leuconedys) gibbons, geographically isolated by the Chindwin River. We assessed the morphological and genetic characteristics of wild animals and museum specimens, and conducted multi-disciplinary analyses using mitochondrial genomic sequences, external morphology, and craniodental characters to evaluate the taxonomic status of the hoolock population in China. The results suggest that hoolocks distributed to the east of the Irrawaddy-Nmai Hka Rivers, which were previously assigned to H. leuconedys, are morphologically and genetically distinct from those to the west of the river, and should be recognized as a new species, the Gaoligong hoolock gibbon or skywalker hoolock gibbon (H. tianxing sp. nov.). We consider that the new species should be categorized as Endangered under IUCN criteria. The discovery of the new species focuses attention on the need for improved conservation of small apes, many of which are in danger of extinction in southern China and Southeast Asia.
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Distribuição Animal , Hylobatidae/classificação , Animais , China , Citocromos b/genética , Hylobatidae/anatomia & histologia , Hylobatidae/genética , Filogenia , Análise de Sequência de DNA , Especificidade da EspécieRESUMO
MicroRNAs (miRNAs) function as essential post-transcriptional modulators of gene expression involved in a wide range of physiologic and pathologic states, including cancer. Numerous miRNAs have been deregulated in hepatocellular carcinoma (HCC). Here, we investigated the role of miR-141 in HCC. Decreased expression of miR-141 was observed in both HCC tissues and cell lines. Ectopic overexpression of miR-141 reduced proliferation, migration, and invasion of HCC cells. E2F transcription factor 3 (E2F3) was confirmed to be a target of miR-141 in HCC cells. Moreover, restoration of E2F3 significantly reversed the tumor suppressive effects of miR-141. Our results suggest a critical role of miR-141 in suppressing metastasis of HCC cells by targeting E2F3.
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Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Fator de Transcrição E2F3/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , MicroRNAs/genética , Interferência de RNA , Sequência de Bases , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células , Fator de Transcrição E2F3/química , Expressão Gênica , Humanos , MicroRNAs/química , Metástase NeoplásicaRESUMO
Background: Immunotherapy stands as a pivotal modality in the therapeutic landscape for the treatment of advanced hepatocellular carcinoma, yet responses vary among patients. This study delves into the potential impact of sarcopenia, myosteatosis and adiposity indicators, as well as their changes during immunotherapy, on treatment response and prognosis in patients with advanced hepatocellular carcinoma treated with immune checkpoint inhibitors. Methods: In this retrospective analysis, 116 patients with advanced hepatocellular carcinoma receiving immune checkpoint inhibitors were recruited. Skeletal muscle, intramuscular, subcutaneous, and visceral adipose tissue were assessed by computed tomography at the level of the third lumbar vertebrae before and after 3 months of treatment. Sarcopenia and myosteatosis were evaluated by skeletal muscle index and mean muscle density using predefined threshold values. Patients were stratified based on specific baseline values or median values, along with alterations observed during the treatment course. Overall survival (OS) and progression-free survival (PFS) were compared using the log-rank test and a multifactorial Cox proportional risk model. Results: A total of 116 patients were recruited and divided into two cohorts, 81 patients for the training set and 35 patients for the validating set. In the overall cohort, progressive sarcopenia (P=0.021) and progressive myosteatosis (P=0.001) were associated with objective response rates, whereas progressive myosteatosis (P<0.001) was associated with disease control rates. In the training set, baseline sarcopenia, myosteatosis, and subcutaneous and visceral adipose tissue were not significantly associated with PFS and OS. In multivariate analysis adjusting for sex, age, and other factors, progressive sarcopenia(P=0.002) and myosteatosis (P=0.018) remained independent predictors of PFS. Progressive sarcopenia (P=0.005), performance status (P=0.006) and visceral adipose tissue index (P=0.001) were all independent predictors of OS. The predictive models developed in the training set also had good feasibility in the validating set. Conclusion: Progressive sarcopenia and myosteatosis are predictors of poor clinical outcomes in patients with advanced hepatocellular carcinoma receiving immune checkpoint inhibitors, and high baseline visceral adiposity is associated with a poorer survival.
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Carcinoma Hepatocelular , Inibidores de Checkpoint Imunológico , Neoplasias Hepáticas , Sarcopenia , Humanos , Sarcopenia/etiologia , Sarcopenia/diagnóstico , Masculino , Feminino , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/efeitos adversos , Pessoa de Meia-Idade , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/tratamento farmacológico , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/tratamento farmacológico , Estudos Retrospectivos , Idoso , Prognóstico , Adulto , Músculo Esquelético/patologia , AdiposidadeRESUMO
OBJECTIVE: Carotid atherosclerosis is a chronic inflammatory disease, which is a major cause of ischemic stroke. The purpose of this study was to analyze the relationship between carotid atherosclerosis and novel inflammatory markers, including platelet to lymphocyte ratio (PLR), neutrophil to lymphocyte ratio (NLR), lymphocyte to monocyte ratio (LMR), platelet to neutrophil ratio (PNR), neutrophil to lymphocyte platelet ratio (NLPR), systemic immune-inflammation index (SII), systemic inflammation response index (SIRI), and aggregate index of systemic inflammation (AISI), in order to find the best inflammatory predictor of carotid atherosclerosis. METHOD: We included 10015 patients who underwent routine physical examinations at the physical examination center of our hospital from January 2016 to December 2019, among whom 1910 were diagnosed with carotid atherosclerosis. The relationship between novel inflammatory markers and carotid atherosclerosis was analyzed by logistic regression, and the effectiveness of each factor in predicting carotid atherosclerosis was evaluated by receiver operating characteristic (ROC) curve and area under the curve (AUC). RESULT: The level of PLR, LMR and PNR in the carotid atherosclerosis group were lower than those in the non-carotid atherosclerosis group, while NLR, NLPR, SII, SIRI and AISI in the carotid atherosclerosis group were significantly higher than those in the non-carotid atherosclerosis group. Logistic regression analysis showed that PLR, NLR, LMR, PNR, NLPR, SII, SIRI, AISI were all correlated with carotid atherosclerosis. The AUC value of NLPR was the highest, which was 0.67, the cut-off value was 0.78, the sensitivity was 65.8%, and the specificity was 57.3%. The prevalence rate of carotid atherosclerosis was 12.4% below the cut-off, 26.6% higher than the cut-off, and the prevalence rate increased by 114.5%. CONCLUSION: New inflammatory markers were significantly correlated with carotid atherosclerosis, among which NLPR was the optimum inflammatory marker to predict the risk of carotid atherosclerosis.
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Biomarcadores , Doenças das Artérias Carótidas , Inflamação , Humanos , Doenças das Artérias Carótidas/sangue , Masculino , Feminino , Pessoa de Meia-Idade , Biomarcadores/sangue , Estudos Retrospectivos , Inflamação/sangue , Estudos de Casos e Controles , Idoso , Neutrófilos , Curva ROC , Plaquetas/patologia , Plaquetas/metabolismo , Linfócitos , Monócitos/metabolismoRESUMO
BACKGROUND: Human hematopoietic organoids have a wide application value for modeling human bone marrow diseases, such as acute hematopoietic radiation injury. However, the manufacturing of human hematopoietic organoids is an unaddressed challenge because of the complexity of hematopoietic tissues. METHODS: To manufacture hematopoietic organoids, we obtained CD34+ hematopoietic stem and progenitor cells (HSPCs) from human embryonic stem cells (hESCs) using stepwise induction and immunomagnetic bead-sorting. We then mixed these CD34+ HSPCs with niche-related cells in Gelatin-methacryloyl (GelMA) to form a three-dimensional (3D) hematopoietic organoid. Additionally, we investigated the effects of radiation damage and response to granulocyte colony-stimulating factor (G-CSF) in hematopoietic organoids. RESULTS: The GelMA hydrogel maintained the undifferentiated state of hESCs-derived HSPCs by reducing intracellular reactive oxygen species (ROS) levels. The established hematopoietic organoids in GelMA with niche-related cells were composed of HSPCs and multilineage blood cells and demonstrated the adherence of hematopoietic cells to niche cells. Notably, these hematopoietic organoids exhibited radiation-induced hematopoietic cell injury effect, including increased intracellular ROS levels, γ-H2AX positive cell percentages, and hematopoietic cell apoptosis percentages. Moreover, G-CSF supplementation in the culture medium significantly improved the survival of HSPCs and enhanced myeloid cell regeneration in these hematopoietic organoids after radiation. CONCLUSIONS: These findings substantiate the successful manufacture of a preliminary 3D hematopoietic organoid from hESCs-derived HSPCs, which was utilized for modeling hematopoietic radiation injury and assessing the radiation-mitigating effects of G-CSF in vitro. Our study provides opportunities to further aid in the standard and scalable production of hematopoietic organoids for disease modeling and drug testing.
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Fator Estimulador de Colônias de Granulócitos , Células-Tronco Hematopoéticas , Organoides , Humanos , Organoides/metabolismo , Organoides/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/citologia , Fator Estimulador de Colônias de Granulócitos/farmacologia , Células-Tronco Embrionárias Humanas/citologia , Células-Tronco Embrionárias Humanas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Regeneração/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Antígenos CD34/metabolismoRESUMO
INTRODUCTION: It is well known that the response to and metabolism of the drugs entering the human body varies widely across individuals. One of the reasons is that such interpersonal differences may be related to gut microbes. On one hand, drugs or xenobiotics entering the human body may affect the composition of the gut microbiome; on the other hand, the gut microbiota may alter the absorption, distribution, metabolism and excretion (abbreviated as ADME) process of drugs or xenobiotics vice versa. However, the majority of studies focused on the interaction of general population cohorts with the gut microbiota, which is incompatible with the real clinic. For example, the gut microbiota is closely associated with the progression and treatment of irritable bowel syndrome, a common functional disorder of the gastrointestinal tract. Under the disease status, the composition of the gut microbiota is altered affecting the pharmacokinetics, efficacy and toxicity of xenobiotics. Concerning irritable bowel syndrome, a few studies reported that the xenobiotics administration process was gut microbial-mediated, while it also affected drug efficacy and toxicity. Thus, the correlation between gut microbiota and xenobiotics administration, especially the drugs administered, should be elucidated. METHOD: This review paper links differences between the gut microbiome and drug metabolism, which play a significant role in the implications for medical therapy and drug development in irritable bowel syndrome indications. RESULT: The human intestinal microbiota permeates the ADME process of orally administered drugs and has the potential to further modify the efficacy and toxicity of agents through the mediation of various enzymes, while at the same time, medications could also alter the composition and function of the human intestinal microbiota.
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There is an urgent medical need to develop effective therapies that can ameliorate damage to the radiation-exposed hematopoietic system. Nanozymes with robust antioxidant properties have a therapeutic potential for mitigating radiation-induced hematopoietic injury. However, enhancing nanozyme recruitment to injured tissues in vivo while maintaining their catalytic activity remains a great challenge. Herein, we present the design and preparation of a biomimetic nanoparticle, a mesenchymal stem cell membrane camouflaged Prussian blue nanozyme (PB@MSCM), which exhibits biocompatible surface properties and demonstrates enhanced injury site-targeting towards the irradiated murine bone marrow niche. Notably, the constructed PB@MSCM possessed redox enzyme-mimic catalytic activity and could scavenge overproduced reactive oxygen species in the irradiated bone marrow cells, both in vitro and ex vivo. More importantly, the administration of PB@MSCM significantly mitigated hematopoietic cell apoptosis and accelerated the regeneration of hematopoietic stem and progenitor cells. Our findings provide a new targeted strategy to improve nanozyme therapy in vivo and mitigate radiation-induced hematopoietic injury.
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Biomimética , Medula Óssea , Camundongos , Animais , Ferrocianetos , Células da Medula ÓsseaRESUMO
Cervical squamous cell carcinoma (CESC) is a prototypical human cancer with well-characterized pathological stages of initiation and progression. However, high-resolution knowledge of the transcriptional programs underlying each stage of CESC is lacking, and important questions remain. We performed single-cell RNA sequencing of 76,911 individual cells from 13 samples of human cervical tissues at various stages of malignancy, illuminating the transcriptional tumorigenic trajectory of cervical epithelial cells and revealing key factors involved in CESC initiation and progression. In addition, we found significant correlations between the abundance of specific myeloid, lymphoid, and endothelial cell populations and the progression of CESC, which were also associated with patients' prognosis. Last, we demonstrated the tumor-promoting function of matrix cancer-associated fibroblasts via the NRG1-ERBB3 pathway in CESC. This study provides a valuable resource and deeper insights into CESC initiation and progression, which is helpful in refining CESC diagnosis and for the design of optimal treatment strategies.
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Carcinoma de Células Escamosas , Neoplasias do Colo do Útero , Feminino , Humanos , Carcinoma de Células Escamosas/genética , Cognição , Células Endoteliais , Células Epiteliais , Neoplasias do Colo do Útero/genéticaRESUMO
With the successful development of the Corona Virus Disease 2019 (COVID-19) vaccines and increased vaccination coverage, great progress in global outbreak control has been made in several countries. However, new coronavirus variants emerge and their rapid spread, causing a new wave of economic and social upheaval worldwide. The spread of new coronavirus variants poses a new and enormous challenge to vaccination and pandemic control, so further studies to explore and develop vaccines for the prevention and control virus infection are warranted. In this review, we provide an overview of the most prevalent variants including Omicron, and explore the effectiveness of COVID-19 vaccines against related variants to better understand existing vaccines and to facilitate improved research into new vaccines. In addition, this review discusses existing strategies to increase vaccine efficacy and introduces novel vaccines by the non-injection route.
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The gene activity underlying cell differentiation is regulated by a diverse set of transcription factors (TFs), histone modifications, chromatin structures and more. Although definitive hematopoietic stem cells (HSCs) are known to emerge via endothelial-to-hematopoietic transition (EHT), how the multi-layered epigenome is sequentially unfolded in a small portion of endothelial cells (ECs) transitioning into the hematopoietic fate remains elusive. With optimized low-input itChIP-seq and Hi-C assays, we performed multi-omics dissection of the HSC ontogeny trajectory across early arterial ECs (eAECs), hemogenic endothelial cells (HECs), pre-HSCs and long-term HSCs (LT-HSCs) in mouse embryos. Interestingly, HSC regulatory regions are already pre-configurated with active histone modifications as early as eAECs, preceding chromatin looping dynamics within topologically associating domains. Chromatin looping structures between enhancers and promoters only become gradually strengthened over time. Notably, RUNX1, a master TF for hematopoiesis, enriched at half of these loops is observed early from eAECs through pre-HSCs but its enrichment further increases in HSCs. RUNX1 and co-TFs together constitute a central, progressively intensified enhancer-promoter interactions. Thus, our study provides a framework to decipher how temporal epigenomic configurations fulfill cell lineage specification during development.
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Cromatina/química , Embrião de Mamíferos/citologia , Células-Tronco Hematopoéticas/citologia , Código das Histonas , Animais , Análise por Conglomerados , Subunidade alfa 2 de Fator de Ligação ao Core/metabolismo , Elementos Facilitadores Genéticos/genética , Genoma , Camundongos Endogâmicos C57BL , Anotação de Sequência Molecular , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/metabolismoRESUMO
Single-cell transcriptional profiling has rapidly advanced our understanding of the embryonic hematopoiesis; however, whether and what role RNA alternative splicing (AS) plays remains an enigma. This is important for understanding the mechanisms underlying splicing-associated hematopoietic diseases and for the derivation of therapeutic stem cells. Here, we used single-cell full-length transcriptome data to construct an isoform-based transcriptional atlas of the murine endothelial-to-hematopoietic stem cell (HSC) transition, which enables the identification of hemogenic signature isoforms and stage-specific AS events. We showed that the inclusion of these hemogenic-specific AS events was essential for hemogenic function in vitro. Expression data and knockout mouse studies highlighted the critical role of Srsf2: Early Srsf2 deficiency from endothelial cells affected the splicing pattern of several master hematopoietic regulators and significantly impaired HSC generation. These results redefine our understanding of the dynamic HSC developmental transcriptome and demonstrate that elaborately controlled RNA splicing governs cell fate in HSC formation.
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Arteriogenesis rather than unspecialized capillary expansion is critical for restoring effective circulation to compromised tissues in patients. Deciphering the origin and specification of arterial endothelial cells during embryonic development will shed light on the understanding of adult arteriogenesis. However, during early embryonic angiogenesis, the process of endothelial diversification and molecular events underlying arteriovenous fate settling remain largely unresolved in mammals. Here, we constructed the single-cell transcriptomic landscape of vascular endothelial cells (VECs) during the time window for the occurrence of key vasculogenic and angiogenic events in both mouse and human embryos. We uncovered two distinct arterial VEC types, the major artery VECs and arterial plexus VECs, and unexpectedly divergent arteriovenous characteristics among VECs that are located in morphologically undistinguishable vascular plexus intra-embryonically. Using computational prediction and further lineage tracing of venous-featured VECs with a newly developed Nr2f2CrexER mouse model and a dual recombinase-mediated intersectional genetic approach, we revealed early and widespread arterialization from the capillaries with considerable venous characteristics. Altogether, our findings provide unprecedented and comprehensive details of endothelial heterogeneity and lineage relationships at early angiogenesis stages, and establish a new model regarding the arteriogenesis behaviors of early intra-embryonic vasculatures.
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Células Endoteliais , Neovascularização Patológica , Animais , Diferenciação Celular , Humanos , Mamíferos , CamundongosRESUMO
Inhibition of type 1 interferon (IFN-I) signaling promotes the control of persistent virus infection, but the underlying mechanisms remain poorly understood. Here, we report that genetic ablation of Ifnar1 specifically in natural killer (NK) cells led to elevated numbers of T follicular helper cells, germinal center B cells, and plasma cells and improved antiviral T cell function, resulting in hastened virus clearance that was comparable to IFNAR1 neutralizing antibody treatment. Antigen-specific B cells and antiviral antibodies were essential for the accelerated control of LCMV Cl13 infection following IFNAR1 blockade. IFNAR1 signaling in NK cells promoted NK cell function and general killing of antigen-specific CD4 and CD8 T cells. Therefore, inhibition of IFN-I signaling in NK cells enhances CD4 and CD8 T cell responses, promotes humoral immune responses, and thereby facilitates the control of persistent virus infection.