RESUMO
Nucleosome positioning can alter the accessibility of DNA-binding proteins to their cognate DNA elements, and thus its precise control is essential for cell identity and function. Mammalian preimplantation embryos undergo temporal changes in gene expression and cell potency, suggesting the involvement of dynamic epigenetic control during this developmental phase. However, the dynamics of nucleosome organization during early development are poorly understood. In this study, using a low-input MNase-seq method, we show that nucleosome positioning is globally obscure in zygotes but becomes well defined during subsequent development. Down-regulation of the chromatin assembly in embryonic stem cells can partially reverse nucleosome organization into a zygote-like pattern, suggesting a possible link between the chromatin assembly pathway and fuzzy nucleosomes in zygotes. We also reveal that YY1, a zinc finger-containing transcription factor expressed upon zygotic genome activation, regulates the de novo formation of well-positioned nucleosome arrays at the regulatory elements through identifying YY1-binding sites in eight-cell embryos. The YY1-binding regions acquire H3K27ac enrichment around the eight-cell and morula stages, and YY1 depletion impairs the morula-to-blastocyst transition. Thus, our study delineates the remodeling of nucleosome organization and its underlying mechanism during early mouse development.
Assuntos
Nucleossomos , Fatores de Transcrição , Animais , Camundongos , Cromatina , Montagem e Desmontagem da Cromatina/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Mamíferos/genética , Nucleossomos/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Round spermatid injection (ROSI) results in a lower birth rate than intracytoplasmic sperm injection, which has hampered its clinical application. Inefficient development of ROSI embryos has been attributed to epigenetic abnormalities. However, the chromatin-based mechanism that underpins the low birth rate in ROSI remains to be determined. Here, we show that a repressive histone mark, H3K27me3, persists from mouse round spermatids into zygotes in ROSI and that round spermatid-derived H3K27me3 is associated with less accessible chromatin and impaired gene expression in ROSI embryos. These loci are initially marked by H3K27me3 but undergo histone modification remodelling in spermiogenesis, resulting in reduced H3K27me3 in normal spermatozoa. Therefore, the absence of epigenetic remodelling, presumably mediated by histone turnover during spermiogenesis, leads to dysregulation of chromatin accessibility and transcription in ROSI embryos. Thus, our results unveil a molecular logic, in which chromatin states in round spermatids impinge on chromatin accessibility and transcription in ROSI embryos, highlighting the importance of epigenetic remodelling during spermiogenesis in successful reproduction.
Assuntos
Histonas , Espermátides , Animais , Cromatina/genética , Cromatina/metabolismo , Histonas/genética , Histonas/metabolismo , Masculino , Camundongos , Oócitos/metabolismo , Herança Paterna , Sêmen/metabolismo , Espermátides/metabolismoRESUMO
Regulation of gene expression through histone modifications underlies cell homeostasis and differentiation. Kdm4d and Kdm4dl exhibited a high degree of similarity and demethylated H3K9me3. However, the physiological functions of these proteins remain unclear. In this study, we generated Kdm4dl mutant mice and found that Kdm4dl was dispensable for mouse development. However, through the generation of Kdm4d mutant mice, we unexpectedly found that Kdm4d mutant male mice were subfertile because of impaired sperm motility. The absence of Kdm4d was associated with an altered distribution of H3K9me3 in round spermatids, suggesting that the Kdm4d-mediated adjustment of H3K9me3 levels is required to generate motile sperm. Further analysis revealed that the absence of Kdm4d did not affect the functionality of sperm nuclei in generating offspring. As KDM4D is specifically expressed in the human testes, our results suggest that KDM4D expression may be a risk factor for human infertility.
RESUMO
Round spermatid injection (ROSI) is the last resort and recourse for men with nonobstructive azoospermia to become biological fathers of their children. However, the ROSI-derived offspring rate is lower than intracytoplasmic sperm injection (ICSI) in mice (20% vs. 60%). This low success rate has hindered the spread of ROSI in ART (Assisted Reproductive Technology). However, the cause of the ROSI-zygote-derived low offspring rate is currently unknown. In the previous studies, we reported that H3K9me3 and H3K27me3 exhibited ectopic localizations in male pronuclei (mPN) of ROSI-zygotes, suggesting that the carried over histone to zygotes conveys epigenetic information. In this study, we analyzed other histone modifications to explore unknown abnormalities. H3K36me3 showed an increased methylation state compared to ICSI-derived embryos but not for H3K4me3. Abnormal H3K36me3 was corrected until 2-cell stage embryos, suggesting a long window of reprogramming ability in ROSI-embryos. Treatment with TSA of ROSI-zygotes, which was reported to be capable of correcting ectopic DNA methylation in ROSI-zygotes, caused abnormalities of H3K36me3 in male and female PN (fPN) of the zygotes. In contrast, round spermatid TSA treatment before ROSI, which was reported to improve the preimplantation development of ROSI-zygotes, showed beneficial effects without toxicity in fPN. Therefore, the results suggest that TSA has some negative effects, but overall, it is effective in the correction of epigenetic abnormalities in ROSI-zygotes. When attempting to correct epigenetic abnormalities, attention should be paid to epigenomes not only in male but also in female pronuclei.
Assuntos
Histonas , Espermátides , Humanos , Criança , Masculino , Feminino , Camundongos , Animais , Espermátides/metabolismo , Histonas/metabolismo , Oócitos/metabolismo , Sêmen/metabolismo , Blastocisto/metabolismo , Metilação de DNARESUMO
BACKGROUND: IgG4-related disease (IgG4-RD) is an immune-mediated fibrotic disorder that has been linked to CD4+ cytotoxic T lymphocytes (CD4+CTLs). The effector phenotype of CD4+CTLs and the relevance of both CD8+ cytotoxic T lymphocytes (CD8+CTLs) and apoptotic cell death remain undefined in IgG4-RD. OBJECTIVE: We sought to define CD4+CTL heterogeneity, characterize the CD8+CTL response in the blood and in lesions, and determine whether enhanced apoptosis may contribute to the pathogenesis of IgG4-RD. METHODS: Blood analyses were undertaken using flow cytometry, cell sorting, transcriptomic analyses at the population and single-cell levels, and next-generation sequencing for the TCR repertoire. Tissues were interrogated using multicolor immunofluorescence. Results were correlated with clinical data. RESULTS: We establish that among circulating CD4+CTLs in IgG4-RD, CD27loCD28loCD57hi cells are the dominant effector subset, exhibit marked clonal expansion, and differentially express genes relevant to cytotoxicity, activation, and enhanced metabolism. We also observed prominent infiltration of granzyme A-expressing CD8+CTLs in disease tissues and clonal expansion in the blood of effector/memory CD8+ T cells with an activated and cytotoxic phenotype. Tissue studies revealed an abundance of cells undergoing apoptotic cell death disproportionately involving nonimmune, nonendothelial cells of mesenchymal origin. Apoptotic cells showed significant upregulation of HLA-DR. CONCLUSIONS: CD4+CTLs and CD8+CTLs may induce apoptotic cell death in tissues of patients with IgG4-RD with preferential targeting of nonendothelial, nonimmune cells of mesenchymal origin.
Assuntos
Antígenos CD/imunologia , Apoptose/imunologia , Linfócitos T CD4-Positivos/imunologia , Doença Relacionada a Imunoglobulina G4/imunologia , Células-Tronco Mesenquimais/imunologia , Linfócitos T Citotóxicos/imunologia , Adulto , Linfócitos T CD4-Positivos/patologia , Feminino , Fibrose , Humanos , Doença Relacionada a Imunoglobulina G4/patologia , Masculino , Células-Tronco Mesenquimais/patologia , Linfócitos T Citotóxicos/patologiaRESUMO
Objectives: In this study, we investigated the diagnostic utility of submandibular gland (SMG) sonography and labial salivary gland (LSG) biopsy as a less invasive procedure for diagnosing IgG4-related dacryoadenitis and sialadenitis (IgG4-DS)Methods: Sixty-eight patients with suspected IgG4-DS by presenting swelling of elevated serum IgG (>1747 mg/dl) and/or swelling glands underwent SMG sonography, LSG biopsy and measurement for serum IgG4. SMG sonographic diagnosis was determined by the following characteristic changes; 'hypoechoic areas of a nodal pattern with high vascularity' and/or 'hypoechoic areas of a reticular pattern in the superficial part'.Results: Thirty-one patients were diagnosed with IgG4-DS, 5 with IgG4-RD unaccompanied by lacrimal and salivary gland lesions, 28 with Sjögren's syndrome, and 4 with malignant lymphoma. The sensitivity, specificity, and accuracy of SMG sonography and LSG biopsy were 100%, 83.8%, 91.2% and 64.5%, 73.8%, 75.0%, respectively. Moreover, those of SMG sonography and LSG biopsy combined with serum IgG4 concentration (>135 mg/dl) were 100%, 94.6%, 97.1% and 64.5%, 91.9%, 79.4%, respectively.Conclusion: LSG biopsy needs to be extremely careful to diagnose IgG4-DS because of its low sensitivity. SMG sonography is sufficient for the diagnosis of IgG4-DS, especially when combined with serologic analysis. Thus, SMG sonography could adapt to the diagnostic criteria of IgG4-DS as a non-invasive method.
Assuntos
Dacriocistite/diagnóstico por imagem , Glândulas Salivares Menores/patologia , Sialadenite/patologia , Glândula Submandibular/diagnóstico por imagem , Ultrassonografia/normas , Adulto , Biópsia/normas , Dacriocistite/sangue , Dacriocistite/patologia , Feminino , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Sialadenite/sangue , Sialadenite/diagnóstico por imagemRESUMO
Inflammatory bowel disease (IBD) is a refractory disease of the gastrointestinal tract that is believed to develop in genetically susceptible individuals. Glycosylation, a type of post-translational modification, is involved in the development of a wide range of diseases, including IBD, by modulating the function of various glycoproteins. To identify novel genes contributing to the development of IBD, we analyzed single nucleotide polymorphisms (SNPs) of glycosylation-related genes in IBD patients and identified MAN2A1, encoding alpha-mannosidase II (α-MII), as a candidate gene. α-MII plays a crucial, but not exclusive, role in the maturation of N-glycans. We also observed that intestinal epithelial cells (IECs), which establish the first-line barrier and regulate gut immunity, selectively expressed α-MII with minimal expression of its isozyme, alpha-mannosidase IIx (α-MIIx). This led us to hypothesize that IEC-intrinsic α-MII is implicated in the pathogenesis of IBD. To test this hypothesis, we generated IEC-specific α-MII-deficient (α-MIIΔIEC) mice. Although α-MII deficiency has been shown to have a minimal effect on N-glycan maturation in most cell types due to the compensation by α-MIIx, ablation of α-MII impaired the maturation of N-glycans in IECs. α-MIIΔIEC mice were less susceptible to dextran sulfate sodium-induced colitis compared with control littermates. In accordance with this, neutrophil infiltration in the colonic mucosa was attenuated in α-MIIΔIEC mice. Furthermore, gene expression levels of neutrophil-attracting chemokines were downregulated in the colonic tissue. These results suggest that IEC-intrinsic α-MII promotes intestinal inflammation by facilitating chemokine expression. We propose SNPs in MAN2A1 as a novel genetic factor for IBD.Key words: inflammatory bowel disease, alpha-mannosidase II, intestinal epithelial cell, N-glycosylation.
Assuntos
Colite/etiologia , Células Epiteliais/metabolismo , alfa-Manosidose/genética , Animais , Quimiocinas/metabolismo , Colite/metabolismo , Colite/veterinária , Colo/patologia , Sulfato de Dextrana/toxicidade , Regulação para Baixo , Microbioma Gastrointestinal , Estudo de Associação Genômica Ampla , Glicosilação , Humanos , Doenças Inflamatórias Intestinais/genética , Doenças Inflamatórias Intestinais/patologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Manosidases/genética , Manosidases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infiltração de Neutrófilos , Polimorfismo de Nucleotídeo Único , alfa-Manosidose/metabolismoRESUMO
YY1 plays multifaceted roles in various cell types. We recently reported that YY1 regulates nucleosome organization in early mouse embryos. However, despite the impaired nucleosome organization in the absence of YY1, the transcriptome was minimally affected in eight-cell embryos. We then hypothesized that YY1 might prepare a chromatin environment to regulate gene expression at later stages. To test this possibility, we performed a transcriptome analysis at the morula stage. We found that a substantial number of genes are aberrantly expressed in the absence of YY1. Furthermore, our analysis revealed that YY1 is required for the transcription of LINE-1 retrotransposons.
RESUMO
Zygotic genome activation (ZGA) after fertilization enables the maternal-to-zygotic transition. However, the global view of ZGA, particularly at initiation, is incompletely understood. Here, we develop a method to capture and sequence newly synthesized RNA in early mouse embryos, providing a view of transcriptional reprogramming during ZGA. Our data demonstrate that major ZGA gene activation begins earlier than previously thought. Furthermore, we identify a set of genes activated during minor ZGA, the promoters of which show enrichment of the Obox factor motif, and find that Obox3 or Obox5 overexpression in mouse embryonic stem cells activates ZGA genes. Notably, the expression of Obox factors is severely impaired in somatic cell nuclear transfer (SCNT) embryos, and restoration of Obox3 expression corrects the ZGA profile and greatly improves SCNT embryo development. Hence, our study reveals dynamic transcriptional reprogramming during ZGA and underscores the crucial role of Obox3 in facilitating totipotency acquisition.
Assuntos
Embrião de Mamíferos , Zigoto , Animais , Camundongos , Reprogramação Celular , Embrião de Mamíferos/metabolismo , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica no Desenvolvimento , Genoma , Proteínas de Homeodomínio/metabolismo , Proteínas de Homeodomínio/genética , Células-Tronco Embrionárias Murinas/metabolismo , RNA/metabolismo , RNA/genética , Transcrição Gênica , Zigoto/metabolismoRESUMO
It remains unclear whether accurate motor performance and cortical activation differ among grasping forms across several force levels. In the present study, a ballistic target force matching task (20%, 40%, 60%, and 80% of maximum voluntary force) with power grip, side pinch, and pulp pinch was utilized to explore the accuracy of the forces generated as well as the muscular activity of intrinsic and extrinsic hand muscles. By using near-infrared spectroscopy, we also examined bilateral dorsolateral prefrontal cortex (DLPFC) activation during the preparatory phase (initial 10 s) of the task. The accuracy of the power grip and pulp pinch was relatively higher than that of the side pinch, and the electromyographic activity of intrinsic hand muscles exhibited a similar trend for power grip and side pinch, while the opposite muscle recruitment pattern was observed for pulp pinch. The increment of DLPFC oxygenation across force levels differed among grasping forms, with greater activity at relatively higher levels in the power grip and side pinch, and at relatively lower levels in the pulp pinch. Taken together, the differential contribution of the DLPFC may be responsible for force generation depending on different grasping forms and force levels.
Assuntos
Força da Mão , Mãos , Humanos , Mãos/fisiologia , Força da Mão/fisiologia , Músculo EsqueléticoRESUMO
Odontogenic tumors (OGTs), which originate from cells of odontogenic apparatus and their remnants, are rare entities. Primary intraosseous carcinoma NOS (PIOC), is one of the OGTs, but it is even rarer and has a worse prognosis. The precise characteristics of PIOC, especially in immunohistochemical features and its pathogenesis, remain unclear. We characterized a case of PIOC arising from the left mandible, in which histopathological findings showed a transition from the odontogenic keratocyst to the carcinoma. Remarkably, the tumor lesion of this PIOC prominently exhibits malignant attributes, including invasive growth of carcinoma cell infiltration into the bone tissue, an elevated Ki-67 index, and lower signal for CK13 and higher signal for CK17 compared with the non-tumor region, histopathologically and immunohistopathologically. Further immunohistochemical analyses demonstrated increased expression of ADP-ribosylation factor (ARF)-like 4c (ARL4C) (accompanying expression of ß-catenin in the nucleus) and yes-associated protein (YAP) in the tumor lesion. On the other hand, YAP was expressed and the expression of ARL4C was hardly detected in the non-tumor region. In addition, quantitative RT-PCR analysis using RNAs and dot blot analysis using genomic DNA showed the activation of Wnt/ß-catenin signaling and epigenetic alterations, such as an increase of 5mC levels and a decrease of 5hmC levels, in the tumor lesion. A DNA microarray and a gene set enrichment analysis demonstrated that various types of intracellular signaling would be activated and several kinds of cellular functions would be altered in the pathogenesis of PIOC. Experiments with the GSK-3 inhibitor revealed that ß-catenin pathway increased not only mRNA levels of ankyrin repeat domain1 (ANKRD1) but also protein levels of YAP and transcriptional co-activator with PDZ-binding motif (TAZ) in oral squamous cell carcinoma cell lines. These results suggested that further activation of YAP signaling by Wnt/ß-catenin signaling may be associated with the pathogenesis of PIOC deriving from odontogenic keratocyst in which YAP signaling is activated.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Cistos Odontogênicos , Tumores Odontogênicos , Fatores de Transcrição , Via de Sinalização Wnt , Humanos , Cistos Odontogênicos/patologia , Cistos Odontogênicos/metabolismo , Tumores Odontogênicos/patologia , Tumores Odontogênicos/metabolismo , Via de Sinalização Wnt/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Fatores de Transcrição/metabolismo , beta Catenina/metabolismo , beta Catenina/genética , Proteínas de Sinalização YAP , Neoplasias Mandibulares/patologia , Neoplasias Mandibulares/metabolismo , Masculino , FemininoRESUMO
Numerous efforts to understand pluripotency in mammals, using pluripotent stem cells in culture, have enabled the generation of artificially induced pluripotent stem cells, which serve as a valuable source for regenerative medicine and the creation of disease models. In contrast to these tremendous successes in the pluripotency field in the past few decades, our understanding of totipotency, which is highlighted by its broader plasticity than pluripotency, is still limited. This is largely attributable to the scarcity of available materials and the lack of in vitro models. However, recent technological advances have unveiled molecular features that characterize totipotent cells. Single-cell or low-input sequencing technologies allow the dissection of pre- and post-fertilization developmental processes at the molecular level with high resolution. In this review, we describe some of the key findings in understanding totipotency and discuss how totipotency is acquired at the beginning of life.
Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes , Animais , MamíferosRESUMO
Oral lichen planus (OLP) is a chronic inflammatory disease associated with T cell infiltration. The crosstalk between oral epithelium and mucosal T cells was considered to be crucial in the pathogenesis of OLP. Here, we selectively extracted the normal epithelium (NE) and lesional epithelium (LE) of buccal mucosa specimens from three patients with OLP by laser capture microdissection due to identify the pathogenic factors. Cathepsin K (CTSK) was identified as one of common upregulated genes in the LE by DNA microarray. Immunohistochemically, CTSK was distinctly detected in and around the LE, while it was rarely seen in the NE. Recent studies showed that CTSK enhanced Toll-like receptor 9 (TLR9) signaling in antigen-presenting cells, leading to Th17 cell differentiation. TLR9 expression mainly co-localized with CD123+ plasmacytoid dendritic cells (pDCs). The number of RORγt-positive cells correlated with that of CTSK-positive cells in OLP tissues. CD123+ pDCs induced the production of Th17-related cytokines (IL-6, IL-23, and TGF-ß) upon stimulation with TLR9 agonist CpG DNA. Moreover, single cell RNA-sequencing analysis revealed that TLR9-positive pDCs enhanced in genes associated with Th17 cell differentiation in comparison with TLR9-negative pDCs. CTSK could induce Th17-related production of CD123+ pDCs via TLR9 signaling to promote the pathogenesis of OLP.
Assuntos
Líquen Plano Bucal , Humanos , Líquen Plano Bucal/patologia , Receptor Toll-Like 9/metabolismo , Subunidade alfa de Receptor de Interleucina-3/metabolismo , Catepsina K/genética , Catepsina K/metabolismo , Células Dendríticas , Epitélio/metabolismo , Imunidade , Receptor 7 Toll-Like/metabolismo , Células Th17/metabolismoRESUMO
The purpose of this study was to investigate the effects of a rise in arterial carbon dioxide pressure (PaCO2 ) on vascular and blood flow responses in the cerebral circulation and active skeletal muscles during dynamic exercise in humans. Thirteen healthy young adults (three women) participated in hypercapnia and normocapnia trials. In both trials, participants performed a two-legged dynamic knee extension exercise at a constant workload that increased heart rate to roughly 100 beats min-1 . In the hypercapnia trial, participants performed the exercise with spontaneous breathing while end-tidal carbon dioxide pressure (PET CO2 ), an index of PaCO2 , was held at 60 mmHg by inhaling hypercapnic gas (O2 : 20.3 ± 0.1%; CO2 : 6.0 ± 0.5%). In the normocapnia trial, minute ventilation during exercise was matched to the value in the hypercapnia trial by performing voluntary hyperventilation with PET CO2 clamped at baseline level (i.e., 40-45 mmHg) through inhalation of mildly hypercapnic gas (O2 : 20.6 ± 0.1%; CO2 : 2.7 ± 1.0%). Middle cerebral artery mean blood velocity and the cerebral vascular conductance index were higher in the hypercapnia trial than in the normocapnia trial. By contrast, vascular conductance in the exercising leg was lower in the hypercapnia trial than in the normocapnia trial. Blood flow to the exercising leg did not differ between the two trials. These results demonstrate that hypercapnia-induced vasomotion in active skeletal muscles is opposite to that in the cerebral circulation. These differential vascular responses may cause a preferential rise in cerebral blood flow.
Assuntos
Dióxido de Carbono , Hipercapnia , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea/fisiologia , Circulação Cerebrovascular/fisiologia , Feminino , Humanos , Músculo Esquelético/fisiologia , Adulto JovemRESUMO
OBJECTIVE: IgG4-related disease (IgG4-RD) is a fibro-inflammatory condition that can affect multiple organs. We previously demonstrated that TLR7-transgenic C57BL/6 mice showed elevated serum IgG1 levels and inflammation with fibrosis in the salivary glands (SGs), lungs, and pancreas. Moreover, we observed extensive Toll-like receptor 7 (TLR-7)-positive CD163+ M2 macrophage infiltration in SGs from IgG4-RD patients. We undertook this study to examine the fibrotic mechanism via the TLR-7 pathway. METHODS: Gene expression in SGs from human TLR7-transgenic mice and IgG4-RD patients was analyzed using DNA microarrays. We extracted the common up-regulated TLR-7-related genes in SGs from TLR7-transgenic mice and IgG4-RD patients. Finally, we investigated the interaction between CD163+ M2 macrophages and fibroblasts before and after stimulation with the TLR-7 agonist loxoribine. RESULTS: In TLR7-transgenic mice and IgG4-RD patients, IRAK3 and IRAK4 were significantly overexpressed. Real-time polymerase chain reaction validated the up-regulation of only IRAK4 in IgG4-RD patients compared with the other groups (P < 0.05). Interleukin-1 receptor-associated kinase 4 (IRAK4) was strongly detected in and around germinal centers in SGs from patients with IgG4-related dacryoadenitis and sialadenitis alone. Double immunofluorescence staining showed that IRAK4-positive cells were mainly colocalized with CD163+ M2 macrophages in SGs (P < 0.05). After stimulation with loxoribine, CD163+ M2 macrophages exhibited significantly enhanced expression of IRAK4 and NF-κB and increased supernatant concentrations of fibrotic cytokines. Finally, we confirmed that the number of fibroblasts was increased by culture with the supernatant of CD163+ M2 macrophages following stimulation with loxoribine (P < 0.05). CONCLUSION: CD163+ M2 macrophages promote fibrosis in IgG4-RD by increasing the production of fibrotic cytokines via TLR-7/IRAK4/NF-κB signaling.
Assuntos
Doença Relacionada a Imunoglobulina G4 , Quinases Associadas a Receptores de Interleucina-1 , NF-kappa B , Receptor 7 Toll-Like , Animais , Antígenos CD , Antígenos de Diferenciação Mielomonocítica , Citocinas/metabolismo , Fibrose , Humanos , Doença Relacionada a Imunoglobulina G4/metabolismo , Quinases Associadas a Receptores de Interleucina-1/metabolismo , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , NF-kappa B/metabolismo , Receptores de Superfície Celular , Receptor 7 Toll-Like/metabolismoRESUMO
Sjögren's syndrome is a chronic autoimmune disorder whose pathogenesis is poorly understood and that lacks effective therapies. Detailed quantitative and spatial analyses of tissues affected by Sjögren's syndrome were undertaken, including the quantitation of the frequency of selected cell-cell interactions in the disease milieu. Quantitative analyses of CD4+ T cell subsets and of CD8+ T cells in the labial salivary glands from untreated patients with primary Sjögren's syndrome revealed that activated CD8+ cytotoxic T cells (CD8+CTLs) were the most prominent T cells in these infiltrates. An accumulation of apoptotic glandular epithelial cells, mainly ductal and acinar cells, was observed, consistent with the impaired salivary secretion often observed in patients with this disease. FasL expressing activated CD8+ T cells were seen to accumulate around Fas expressing apoptotic epithelial cells. Quantitative analyses of apoptotic cell types and of conjugates between cytotoxic T cells and epithelial cells undergoing apoptosis suggest that Sjögren's syndrome is primarily driven by CD8+CTL mediated execution of epithelial cells mainly represented by ductal and acinar cells.
Assuntos
Síndrome de Sjogren , Linfócitos T CD8-Positivos , Humanos , Glândulas Salivares/metabolismo , Glândulas Salivares Menores/patologia , Síndrome de Sjogren/patologia , Linfócitos T Citotóxicos/patologiaRESUMO
Emergency medical responders (EMRs) who treat victims during a radiation emergency are at risk of radiation exposure. In this study, the exposure dose to EMRs treating hypothetically contaminated patients was estimated using a Monte Carlo simulation, and the findings may be useful for educating EMRs and reducing their anxiety. The Monte Carlo simulation estimated radiation doses for adult computational phantoms based on radioactive contamination conditions and radiation dosages from previous studies. At contamination conditions below the typical upper limit of general Geiger-Müller survey meters, the radiation doses to EMRs were estimated to be less than 1 µSv per hour. In cases with greater contamination due to mishandling of an intense radioactive source (hundreds of GBq), the radiation doses to EMRs could reach approximately 100 mSv per hour. These results imply that a radiological accident with a highly radioactive source could expose EMR to significant radiation that exceeds their dose limit. Thus, authorities and other parties should ensure that EMRs receive appropriate education and training regarding measures that can be taken to protect themselves from the possibility of excessive radiation exposure. The results of this study may provide EMRs with information to take appropriate protective measures, although it is also important that they not hesitate to perform lifesaving measures because of concerns regarding radiation.
Assuntos
Socorristas , Doses de Radiação , Exposição à Radiação/análise , Monitoramento de Radiação , Proteção Radiológica , Humanos , Método de Monte Carlo , Imagens de Fantasmas , Monitoramento de Radiação/instrumentação , Monitoramento de Radiação/métodos , Liberação Nociva de RadioativosRESUMO
The Japanese government formulated the Nuclear Emergency Response Guidelines in response to the Fukushima Daiichi Nuclear Power Plant accident (FDNPP accident) caused by the Great East Japan Earthquake in March 2011. Under these guidelines, Japan has established its current nuclear disaster response system. This manuscript outlines the transition of Japan's nuclear disaster response system before and after the FDNPP accident and also shows the results of a questionnaire survey on the level of preparation the prefecture currently has for the evacuation of residents at the time of a nuclear disaster. About 70% of the prefectures where nuclear facilities are located or adjacent have completed or are in the process of completing evacuation plans, and all except one indicated they have the equipment needed to perform radiation contamination inspections of residents. These results suggest that activities are taking place throughout Japan to build a new disaster response system. It will be important to verify whether the evacuation manuals prepared by prefectural governments are effective through large-scale training and to develop human resources for performing radiation contamination inspections of evacuating residents.
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Terremotos , Acidente Nuclear de Fukushima , Humanos , Japão , Centrais Nucleares , Inquéritos e QuestionáriosRESUMO
OBJECTIVE: IgG4-related disease (IgG4-RD) is a unique inflammatory disorder in which Th2 cytokines promote IgG4 production. In addition, recent studies have implicated the Toll-like receptor (TLR) pathway. This study was undertaken to examine the expression of TLRs in salivary glands (SGs) from patients with IgG4-RD. METHODS: SGs from 15 patients with IgG4-RD, 15 patients with Sjögren's syndrome (SS), 10 patients with chronic sialadenitis, and 10 healthy controls were examined histologically. TLR family gene expression (TLR-1 through TLR-10) was analyzed by DNA microarray in the submandibular glands (SMGs). Up-regulation of TLRs was confirmed in SGs from patients with IgG4-RD. Finally, the phenotype of human TLR-7 (huTLR-7)-transgenic C57BL/6 mice was assessed before and after stimulation with TLR agonist. RESULTS: In patients with IgG4-RD, TLR-4, TLR-7, TLR-8, and TLR-9 were overexpressed. Polymerase chain reaction validated the up-regulation of TLR-7 in IgG4-RD compared with the other groups. Immunohistochemical analysis confirmed strong infiltration of TLR-7-positive cells in the SGs of patients with IgG4-RD. Double immunohistochemical staining showed that TLR-7 expression colocalized with CD163+ M2 macrophages. After in vitro stimulation with a TLR-7 agonist, CD163+ M2 macrophages produced higher levels of interleukin-33 (IL-33), which is a Th2-activating cytokine. In huTLR-7-transgenic mice, the focus and fibrosis scores in SMGs, pancreas, and lungs were significantly higher than those in wild-type mice (P < 0.05). Moreover, the concentration of serum IgG, IgG1, and IL-33 in huTLR-7-transgenic mice was distinctly increased upon stimulation with a TLR-7 agonist (P < 0.05). CONCLUSION: TLR-7-expressing M2 macrophages may promote the activation of Th2 immune responses via IL-33 secretion in IgG4-RD.
Assuntos
Doença Relacionada a Imunoglobulina G4/imunologia , Interleucina-33/imunologia , Macrófagos/imunologia , Receptor 7 Toll-Like/imunologia , Adulto , Idoso , Animais , Estudos de Casos e Controles , Feminino , Humanos , Doença Relacionada a Imunoglobulina G4/genética , Doença Relacionada a Imunoglobulina G4/metabolismo , Masculino , Camundongos Transgênicos , Pessoa de Meia-Idade , Sialadenite , Transdução de Sinais , Síndrome de Sjogren , Glândula Submandibular , Células Th2/imunologia , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/imunologia , Receptor 7 Toll-Like/agonistas , Receptor 7 Toll-Like/genética , Receptor 8 Toll-Like/genética , Receptor 8 Toll-Like/imunologia , Receptor Toll-Like 9/genética , Receptor Toll-Like 9/imunologia , Regulação para CimaRESUMO
Tumor-associated macrophages (TAMs) promote tumor progression and inhibit anti-tumor immune response by producing various mediators and preferentially express CD163, CD204, and CD206. However, the role of these TAM subsets in oral squamous cell carcinoma (OSCC) remains unclear. Here we investigated the expression and function of TAM subsets in OSCC, especially in cancer cell proliferation. Biopsy sample from 44 patients with OSCC were examined for the expression of TAM markers and EGF by immunohistochemistry. EGF production of TAM subsets isolated from OSCC patients was assessed by flow cytometry. We also examined the effect of conditioned medium from TAM subsets on the proliferation of OSCC cells. CD163+ cells were detected diffusely all over the tumor and connective tissue area, while CD204+ and CD206+ cells were mainly detected in/around the tumors. Flow cytometric analysis found that CD206+ TAMs strongly produced EGF compared with CD163+ and CD204+ TAMs. Cell proliferation and invasion of OSCC cells cultured with conditioned medium of CD206+ TAMs were strongly enhanced and inhibited by anti-EGFR. The number of CD206+ TAMs positively correlated with worse clinical prognosis. Our results revealed differences in localization and EGF production among these TAM subsets. CD206+ TAMs might play a critical role in the proliferation of OSCC via EGF production.