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[This corrects the article DOI: 10.1186/s12953-015-0063-8.].
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Activation of the nuclear transcription factor κB (NF-κB) regulates the expression of inflammatory genes crucially involved in the pathogenesis of inflammatory diseases. NF-κB governs the expression of adhesion molecules that play a pivotal role in leukocyte-endothelium interactions. We uncovered the crucial role of NF-κB activation within endothelial cells in models of immune-mediated diseases using a "sneaking ligand construct" (SLC) selectively inhibiting NF-κB in the activated endothelium. The recombinant SLC1 consists of three modules: (i) an E-selectin targeting domain, (ii) a Pseudomonas exotoxin A translocation domain, and (iii) a NF-κB Essential Modifier-binding effector domain interfering with NF-κB activation. The E-selectin-specific SLC1 inhibited NF-κB by interfering with endothelial IκB kinase 2 activity in vitro and in vivo. In murine experimental peritonitis, the application of SLC1 drastically reduced the extravasation of inflammatory cells. Furthermore, SLC1 treatment significantly ameliorated the disease course in murine models of rheumatoid arthritis. Our data establish that endothelial NF-κB activation is critically involved in the pathogenesis of arthritis and can be selectively inhibited in a cell type- and activation stage-dependent manner by the SLC approach. Moreover, our strategy is applicable to delineating other pathogenic signaling pathways in a cell type-specific manner and enables selective targeting of distinct cell populations to improve effectiveness and risk-benefit ratios of therapeutic interventions.
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Artrite/tratamento farmacológico , Artrite/imunologia , Células Endoteliais/imunologia , Regulação da Expressão Gênica/imunologia , NF-kappa B/antagonistas & inibidores , Proteínas Recombinantes de Fusão/imunologia , Animais , Proteínas de Bactérias/metabolismo , Clonagem Molecular , Selectina E/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Células Endoteliais/efeitos dos fármacos , Escherichia coli , Imunofluorescência , Regulação da Expressão Gênica/efeitos dos fármacos , Camundongos , Proteínas Recombinantes de Fusão/farmacologia , Transdução de Sinais/imunologiaRESUMO
BACKGROUND: Adrenal glands are essential endocrine organs composed of two embryological distinct tissues. Morphological changes during their development are well described, but less understood with regard to their molecular mechanisms. To identify proteins and pathways, which drive the initial steps of the specification of the endocrine function of the adrenal gland, rat's adrenal glands were isolated at different embryonic days (E): E14, E16, E18, E19 and postnatal day 1 (P1). RESULTS: The alteration of the proteome during the stages E16, E19 and P1 was investigated by combining two dimensional gel electrophoresis and mass spectrometric analysis. Out of 594 excised protein spots, 464 spots were identified, resulting in 203 non-redundant proteins. The ontogenic classification of the identified proteins according to their molecular function resulted in 10 different categories, whereas the classification of their biological processes resulted in 19 different groups. This gives an insight into the complex mechanisms underlying adrenal gland development. Interestingly, the expression of retinoic acid pathway proteins was decreased during the development of the adrenal gland, suggesting that this pathway is only important at early stages. On the other hand, key proteins of the cholesterol synthesis increased their expression significantly at E19 revealing the initiation of the endocrine specialization of the adrenal glands. CONCLUSIONS: This study presents the first comprehensive wide proteome analysis of three different stages of embryonic adrenal gland development. The identified proteins, which were expressed in early stages of development, will shed light on the molecular mechanisms underlying embryonic development of the adrenal gland.
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Clinical outcome of patients suffering from head neck squamous cell carcinomas is still poor due to recurrent disease and surgical limitations. There is still a demand for multimodality approaches and new therapeutic options. Hypericin is a promising phototoxic drug which was investigated for its effects on head neck squamous cell carcinoma cells in vitro. FaDu cells incubated with or without hypericin were illuminated (450-700 nm, 50,000 lx) for different time periods. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide- and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay were used to score metabolic and apoptotic activity. Even after the shortest illumination FaDu cells incubated with hypericin showed massive reduction of metabolism and excessive apoptosis. This was present even with the lowest hypericin concentration. Cells without hypericin or without illumination were not affected. These photosensitizing effects of hypericin could be suitable for clinical application and could lead to the development of an intraoperative photodynamic therapy of head neck squamous cell carcinomas.
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Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/patologia , Perileno/análogos & derivados , Fármacos Fotossensibilizantes/farmacologia , Antracenos , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Marcação In Situ das Extremidades Cortadas , Perileno/farmacologia , Fotoquimioterapia , Carcinoma de Células Escamosas de Cabeça e PescoçoRESUMO
One of the most common concerns of patients undergoing surgery is preoperative anxiety, with a prevalence of up to 48%. The effects of preoperative anxiety continue beyond the preoperative period and are associated with more severe postoperative pain and poorer treatment outcomes. Treatment options for preoperative anxiety are often limited as sedatives cause side effects and their efficacy remains controversial. Placebo research has shown that optimization of positive treatment expectations, as can be achieved through placebo administration and education, has clinically relevant effects on preoperative anxiety, pain and treatment outcomes. As the administration of masked placebos raises ethical questions, clinical studies have increasingly focused on the use of open, non-deceptive placebo administration (open-label placebo, OLP). The use of OLPs to reduce preoperative anxiety and modify clinically relevant postoperative outcomes has not yet been investigated. This bicentric, prospective, randomized-controlled clinical trial (PATE Trial; German Registry for Clinical Studies DRKS00033221), an associated project of the Collaborative Research Center (CRC) 289 "Treatment Expectation", aims to alleviate preoperative anxiety by optimizing positive treatment expectations facilitated by OLP. Furthermore, this study examines a potential enhancement of these effects through aspects of observational learning, operationalized by a positive expectation-enhancing video. In addition, patient's perspective on the self-efficacy and appropriateness of OLPs prior to surgery will be assessed. To achieve these objectives, female patients will be randomized into three groups before undergoing gynecological laparoscopic surgery. One group receives the OLP with a positive rationale conveyed by a study physician. A second group receives the same intervention, OLP administration and rationale provided by a physician, and additionally watches a video on OLP presenting a satisfied patient. A third group receives standard treatment as usual (TAU). Outcome measures will be effects on preoperative anxiety and postoperative experience, particularly visceral and somatic postoperative pain. As the non-deceptive administration of placebos; when indicated; may yield positive outcomes without side effects, and as current treatment of preoperative anxiety is limited, evidence from clinical placebo research has the potential to improve outcomes and patient experience in the surgical setting.
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Macrophages play a central role in host defense against mycobacterial infection and anti- TNF therapy is associated with granuloma disorganization and reactivation of tuberculosis in humans. Here, we provide evidence for the presence of a T cell receptor (TCR) αß based recombinatorial immune receptor in subpopulations of human and mouse monocytes and macrophages. In vitro, we find that the macrophage-TCRαß induces the release of CCL2 and modulates phagocytosis. TNF blockade suppresses macrophage-TCRαß expression. Infection of macrophages from healthy individuals with mycobacteria triggers formation of clusters that express restricted TCR Vß repertoires. In vivo, TCRαß bearing macrophages abundantly accumulate at the inner host-pathogen contact zone of caseous granulomas from patients with lung tuberculosis. In chimeric mouse models, deletion of the variable macrophage-TCRαß or TNF is associated with structurally compromised granulomas of pulmonary tuberculosis even in the presence of intact T cells. These results uncover a TNF-regulated recombinatorial immune receptor in monocytes/macrophages and demonstrate its implication in granuloma formation in tuberculosis.
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Granuloma/imunologia , Macrófagos/imunologia , Monócitos/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Tuberculose Pulmonar/imunologia , Animais , Quimiocina CCL2/biossíntese , Granuloma/patologia , Humanos , Camundongos , Receptores do Fator de Necrose Tumoral/imunologia , Tuberculose Pulmonar/microbiologia , Tuberculose Pulmonar/patologia , Fator de Necrose Tumoral alfa/imunologia , Recombinação V(D)J/imunologiaRESUMO
RATIONALE: Telethonin (also known as titin-cap or t-cap) is a 19-kDa Z-disk protein with a unique ß-sheet structure, hypothesized to assemble in a palindromic way with the N-terminal portion of titin and to constitute a signalosome participating in the process of cardiomechanosensing. In addition, a variety of telethonin mutations are associated with the development of several different diseases; however, little is known about the underlying molecular mechanisms and telethonin's in vivo function. OBJECTIVE: Here we aim to investigate the role of telethonin in vivo and to identify molecular mechanisms underlying disease as a result of its mutation. METHODS AND RESULTS: By using a variety of different genetically altered animal models and biophysical experiments we show that contrary to previous views, telethonin is not an indispensable component of the titin-anchoring system, nor is deletion of the gene or cardiac specific overexpression associated with a spontaneous cardiac phenotype. Rather, additional titin-anchorage sites, such as actin-titin cross-links via α-actinin, are sufficient to maintain Z-disk stability despite the loss of telethonin. We demonstrate that a main novel function of telethonin is to modulate the turnover of the proapoptotic tumor suppressor p53 after biomechanical stress in the nuclear compartment, thus linking telethonin, a protein well known to be present at the Z-disk, directly to apoptosis ("mechanoptosis"). In addition, loss of telethonin mRNA and nuclear accumulation of this protein is associated with human heart failure, an effect that may contribute to enhanced rates of apoptosis found in these hearts. CONCLUSIONS: Telethonin knockout mice do not reveal defective heart development or heart function under basal conditions, but develop heart failure following biomechanical stress, owing at least in part to apoptosis of cardiomyocytes, an effect that may also play a role in human heart failure.
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Insuficiência Cardíaca/metabolismo , Coração/fisiopatologia , Mecanotransdução Celular , Proteínas Musculares/deficiência , Miocárdio/metabolismo , Adaptação Fisiológica , Animais , Animais Geneticamente Modificados , Apoptose , Fenômenos Biomecânicos , Linhagem Celular Tumoral , Conectina , Modelos Animais de Doenças , Ecocardiografia , Fibrose , Genótipo , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/patologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Camundongos , Camundongos Knockout , Proteínas Musculares/genética , Miocárdio/patologia , Fenótipo , Interferência de RNA , Ratos , Sarcômeros/metabolismo , Estresse Mecânico , Transfecção , Proteína Supressora de Tumor p53/metabolismoRESUMO
The sentinel and immune functions of microglia require rapid and appropriate reactions to infection and damage. Their Toll-like receptors (TLRs) sense both as threats. However, whether activated microglia mount uniform responses or whether subsets conduct selective tasks is unknown. We demonstrate that murine microglia reorganize their responses to TLR activations postnatally and that this process comes with a maturation of TLR4-organized functions. Although induction of MHCI for antigen presentation remains as a pan-populational feature, synthesis of TNFα becomes restricted to a subset, even within adult central nervous system regions. Response heterogeneity is evident ex vivo, in situ, and in vivo, but is not limited to TNFα production or to TLR-triggered functions. Also, clearance activities for myelin under physiological and pathophysiological conditions, IFNγ-enforced upregulation of MHCII, or challenged inductions of other proinflammatory factors reveal dissimilar microglial contributions. Notably, response heterogeneity is also confirmed in human brain tissue. Our findings suggest that microglia divide by constitutive and inducible capacities. Privileged production of inflammatory mediators assigns a master control to subsets. Sequestration of clearance of endogenous material versus antigen presentation in exclusive compartments can separate potentially interfering functions. Finally, subsets rather than a uniform population of microglia may assemble the reactive phenotypes in responses during infection, injury, and rebuilding, warranting consideration in experimental manipulation and therapeutic strategies.
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Microglia/classificação , Microglia/metabolismo , Receptor 4 Toll-Like/metabolismo , Idoso , Animais , Animais Recém-Nascidos , Encéfalo/metabolismo , Encéfalo/patologia , Células Cultivadas , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microglia/patologia , Receptor 4 Toll-Like/fisiologiaRESUMO
Proper illumination is essential for light microscopy. Whereas in early years incandescent light was the only illumination, today, more and more specialized light sources, such as lasers or arc lamps are used. Because of the high efficiency and brightness that light-emitting diodes (LED) have reached today, they have become a serious alternative for almost all kinds of illumination in light microscopy. LED have a high durability, do not need expensive electronics, and they can be switched in nanoseconds. Besides this, they are available throughout the UV/Vis/NIR-spectrum with a narrow bandwidth. This makes them ideal light sources for fluorescence microscopy. The white LED, with a color temperature ranging from 2,600 up to 5,000 K is an excellent choice for bright-field illumination with the additional advantage of simple brightness adjustments without changing the spectrum. This review discusses the different LED types, their use in the fluorescence microscope, and discusses LED as specialized illumination sources for Förster resonance energy transfer and fluorescent lifetime imaging microscopy.
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Transferência Ressonante de Energia de Fluorescência/instrumentação , Iluminação/instrumentação , Microscopia Confocal/instrumentação , Microscopia de Fluorescência/instrumentação , Desenho de Equipamento , LuzRESUMO
INTRODUCTION: Sepsis is characterized by systemic microvascular dysfunction. Endothelial progenitor cells (EPCs) are critically involved in maintaining vascular homeostasis under both physiological and pathological conditions. The aim of the present study was to analyze the endothelial progenitor cell system in patients suffering from sepsis with acute renal dysfunction. METHODS: Patients with newly diagnosed sepsis were recruited from the ICU in a nonrandomized prospective manner. Blood samples were obtained within the first 12 hours after the diagnosis of sepsis. For quantifying endothelial progenitor cells (EPCs), CD133+/Flk-1+ cells were enumerated by cytometric analysis. Analysis of EPC proliferation was performed by a colony-forming units (CFU) assay. Blood concentrations of proangiogenic mediators were measured by ELISA. Acute renal dysfunction was diagnosed according to the Acute Kidney Injury Network (AKIN) criteria. Depending on the overall mean creatinine concentration during the stay at the ICU, patients were either assigned to a 'normal creatinine group' or to a 'high creatinine group'. Survival rates, frequency of dialysis, the simplified acute physiology score (SAPS) II scores, and different laboratory parameters were collected/used for further clinical characterization RESULTS: Circulating EPCs were significantly higher in all sepsis patients included in the study as opposed to healthy controls. Patients within the 'high creatinine group' showed an even more pronounced EPC increase. In contrast, EPC proliferation was severely affected in sepsis. Neither total circulating EPCs nor EPC proliferation differed between patients requiring dialysis and patients without renal replacement therapy. Cell numbers and cell proliferation also did not differ between surviving patients and patients with sepsis-related death. Serum levels of vascular endothelial growth factor (VEGF), stromal derived factor-1 (SDF-1), and Angiopoietin-2 were higher in sepsis than in healthy controls. Sepsis patients within the 'high creatinine group' showed significantly higher mean serum levels of uric acid. CONCLUSIONS: Sepsis significantly affects the endothelial progenitor cell system, as reflected by increased EPC numbers, increased concentrations of proangiogenic mediators, and reduced proliferative capacity of the cells. This occurs independently from the frequency of dialysis and from patient survival. Increased serum levels of uric acid are possibly responsible for stronger EPC mobilization in sepsis patients with higher average creatinine levels.
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Células Endoteliais/citologia , Nefropatias/sangue , Sepse/sangue , Células-Tronco/citologia , Doença Aguda , Idoso , Estudos de Casos e Controles , Contagem de Células , Movimento Celular , Proliferação de Células , Feminino , Humanos , Unidades de Terapia Intensiva , Nefropatias/etiologia , Nefropatias/fisiopatologia , Masculino , Estudos Prospectivos , Sepse/complicações , Sepse/fisiopatologiaRESUMO
This review focuses on technical advances in fluorescence microscopy techniques including laser scanning techniques, fluorescence-resonance energy transfer (FRET) microscopy, fluorescence lifetime imaging (FLIM), stimulated emission depletion (STED)-based super-resolution microscopy, scanning confocal endomicroscopes, thin-sheet laser imaging microscopy (TSLIM), and tomographic techniques such as early photon tomography (EPT) as well as on clinical laser-based endoscopic and microscopic techniques. We will also discuss the new developments in the field of fluorescent dyes and fluorescent genetic reporters that enable new possibilities in high-resolution and molecular imaging both in in vitro and in vivo. Small animal and tissue imaging benefit from the development of new fluorescent proteins, dyes, and sensing constructs that operate in the far red and near-infrared spectrum.
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Células , Endoscopia/métodos , Transferência Ressonante de Energia de Fluorescência/métodos , Microscopia de Fluorescência/métodos , Imagem Molecular/métodos , Tomografia/métodos , Animais , Células/metabolismo , Células/ultraestrutura , Transferência Ressonante de Energia de Fluorescência/instrumentação , Corantes Fluorescentes/metabolismo , Genes Reporter , Humanos , Lasers , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Microscopia de Fluorescência/instrumentação , Imagem Molecular/instrumentaçãoRESUMO
BACKGROUND AND AIM: Endothelial progenitor cells (EPCs) have been shown to promote neovascularization under physiologic and pathologic conditions. Statins have been documented to increase the total number of circulating EPCs in long-term treated patients. Lipid apheresis is used to treat patient with refractory hyperlipidemia. The aim of our study was to evaluate whether lipid apheresis is associated with EPC mobilization. METHODS: Thirteen patients with refractory hyperlipidemia (analysis at the beginning and at the end of a single lipid apheresis treatment) and 10 healthy controls were included into the study. For quantifying total peripheral EPCs, CD133+/Flk-1+ myelo-monocytic blood cells were enumerated by flow cytometry. The proliferative potential of EPCs was evaluated by a "colony-forming unit" assay. In some patients, EPC eNOS expression was evaluated before and after treatment. RESULTS: Circulating EPCs and the cells' proliferative activity were lower in hyperlipidemia patients as compared to controls (0.14 +/- 0.07 vs. 0.6 +/- 0.14, P = 0.01, and 13.9 +/- 4.9 vs. 45.6 +/- 8.1, P = 0.0007). Lipid apheresis treatment was not associated with an increase in total EPCs. The cells' proliferative activity was strongly stimulated by lipid apheresis as reflected by an increase in the number of EPC colonies (13.9 +/- 4.9 to 34.1 +/- 7.3, P = 0.035). Analysis of EPC eNOS expression revealed a threefold increase in the cellular expression intensity after lipid apheresis. CONCLUSIONS: Patients with refractory hyperlipidemia exhibit lower peripheral EPC numbers and a lower proliferative activity of circulating EPCs than healthy controls. A single lipid apheresis treatment significantly stimulates EPC proliferation, it furthermore increases cellular eNOS. In summary, these results show that lipid apheresis mediates beneficial effects on the EPC system as an essential element in the process of vascular repair in the human organism.
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Remoção de Componentes Sanguíneos , Células Endoteliais/metabolismo , Hiperlipidemias/sangue , Hiperlipidemias/terapia , Lipoproteínas LDL , Células-Tronco/metabolismo , Antígeno AC133 , Adulto , Idoso , Antígenos CD/metabolismo , Proliferação de Células , Feminino , Citometria de Fluxo/métodos , Regulação Enzimológica da Expressão Gênica , Glicoproteínas/metabolismo , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Óxido Nítrico Sintase Tipo III/biossíntese , Peptídeos/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismoRESUMO
The renal cell carcinoma (RCC) is extremely resistant to chemotherapy and radiotherapy. The prognosis of patients with metastatic RCC still remains poor, the median survival is less than 12 months. Therefore, new therapeutic options are desirable. The aim of this study was to investigate the photosensitizing and radiosensitizing effects of hypericin on human RCC cells in vitro. First the RCC-derived cell lines A498 and ACHN were incubated with different concentrations of hypericin. In vitro uptake and intracellular distribution of hypericin were confirmed by fluorescence microscopy. Subsequently cells were illuminated and irradiated with a dose of 2-8 Gy, respectively. Finally, metabolic activity, apoptosis and clonogenic survival were investigated. Uptake of hypericin was observed for almost all cells. Hypericin treatment combined with illumination led to a 94-97% decrease in metabolic activity and caused apoptosis in nearly 100% of RCC cells. Hypericin enhanced the radiosensitivity of A498 cells in vitro. The clonogenic survival after irradiation was significantly reduced by hypericin treatment. Taken together, the photosensitizing and radiosensitizing effects of hypericin on human RCC cells we found in this investigation could be of clinical relevance, e.g. for radiotherapy and intraoperative photodynamic therapy, respectively.
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Carcinoma de Células Renais/patologia , Perileno/análogos & derivados , Fármacos Fotossensibilizantes/farmacologia , Antracenos , Carcinoma de Células Renais/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Perileno/farmacologiaRESUMO
Treatment of childhood rhabdomyosarcoma is limited by recurrent disease and the development of multidrug resistance. Therefore, novel treatment options are desirable. Photodynamic therapy (PDT) using the photodynamic agent hypericin is proposed as an alternative approach for intraoperative visualization and treatment of this disease. The aim of this study was to investigate in vitro effects of hypericin on childhood rhabdomyosarcoma and to evaluate photodynamic therapy as a possible basis for treatment. Rhabdomyosarcoma cells and fibroblasts (control) were incubated with increasing concentrations of hypericin. in vitro uptake and visualization of hypericin was evaluated by fluorescence microscopy and FACS. For photodynamic therapy, cells were exposed to white light for different time periods. Cytopathologic effects were assessed using standard histology. Cancer cells were investigated for cell viability (MTT assay), proliferative activity (Ki-67 assay), and apoptosis (TUNEL test). A 100% uptake of hypericin was found within the population of rhabdomyosarcoma cells. Uptake of hypericin in the fibroblasts was much less than in rhabdomyosarcoma cells. Hypericin without exposure to white light had no effect on tumor cell viability. After irradiation, PDT resulted in a nearly complete inhibition of cell proliferation of rhabdomyosarcoma cells with a corresponding increase in the frequency of apoptosis. In fibroblasts, PDT was less effective compared to tumor cells. Our data suggest hypericin as a novel tool for visualization and photodynamic therapy of childhood rhabdomyosarcoma.
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Fotoquimioterapia/métodos , Rabdomiossarcoma/terapia , Animais , Antracenos , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Separação Celular , Sobrevivência Celular , Criança , Fragmentação do DNA , Fibroblastos/metabolismo , Citometria de Fluxo , Humanos , Antígeno Ki-67/biossíntese , Camundongos , Perileno/análogos & derivados , Perileno/farmacologia , Sais de Tetrazólio/farmacologia , Tiazóis/farmacologiaRESUMO
Costimulatory signals play a key role in regulating T cell activation and are believed to have decisive influence in the inciting and perpetuating cellular effector mechanisms in autoimmune diseases such as multiple sclerosis (MS). Inducible costimulator protein (ICOS), a recently identified member of the CD28-family, presumably affects the differentiation of Th1/Th2 cells after primary activation and modulates the immune response of effector/memory T cells. This study examines the expression and functional role of ICOS costimulation in healthy donors and patients with MS. After nonspecific or antigen-specific stimulation, ICOS is preferentially expressed on CD4 Th2-T cells. ICOS-costimulation affects the production of Th1 and Th2 cytokines both in the absence and presence of B7/CD28 costimulation, thus suggesting that ICOS costimulation can modulate cytokine secretion also in a CD28-independent manner. Levels of constitutive and inducible ICOS expression on human T cell subsets from peripheral blood were quantified in healthy donors and patients with MS. Constitutive expression of ICOS on T cells varies between 0.1% and 42.3%. There were no significant differences between both groups in the baseline expression or inducibility of ICOS on CD4 or CD8 T cells. ICOS expression could be demonstrated on CSF T lymphocytes in patients with acute MS relapses but was not elevated compared with peripheral blood. In essence we show that ICOS is upregulated on human T cells after stimulation and can modulate both Th1 and Th2 cytokine production in the absence and presence of B7-costimulation. In MS patients we demonstrate the functionality of the ICOS costimulatory pathway. Potential implications of ICOSL/ICOS interactions for MS immunopathogenesis are discussed.
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Antígenos CD/fisiologia , Antígenos de Diferenciação de Linfócitos T/biossíntese , Antígenos de Diferenciação de Linfócitos T/fisiologia , Antígeno B7-1/fisiologia , Antígenos CD28/fisiologia , Glicoproteínas de Membrana/fisiologia , Esclerose Múltipla/imunologia , Subpopulações de Linfócitos T/imunologia , Adjuvantes Imunológicos/farmacologia , Adulto , Animais , Antígenos CD/biossíntese , Antígenos CD/genética , Antígenos de Diferenciação de Linfócitos T/líquido cefalorraquidiano , Antígenos de Diferenciação de Linfócitos T/genética , Antígeno B7-1/biossíntese , Antígeno B7-1/genética , Antígeno B7-2 , Linhagem Celular , Técnicas de Cocultura , Feminino , Citometria de Fluxo , Acetato de Glatiramer , Humanos , Proteína Coestimuladora de Linfócitos T Induzíveis , Interferon beta/farmacologia , Interferon gama/biossíntese , Interleucina-4/biossíntese , Células L , Masculino , Glicoproteínas de Membrana/biossíntese , Glicoproteínas de Membrana/genética , Camundongos , Pessoa de Meia-Idade , Esclerose Múltipla/líquido cefalorraquidiano , Esclerose Múltipla/metabolismo , Peptídeos/farmacologia , Receptores de Quimiocinas/biossíntese , Subpopulações de Linfócitos T/metabolismo , Células Th1/imunologia , Células Th1/metabolismo , Células Th2/imunologia , Células Th2/metabolismo , Transfecção , Regulação para Cima/imunologiaRESUMO
The isotopic composition of different materials can be imaged by secondary ion mass spectrometry. In biology, this method is mainly used to study cellular metabolism and turnover, by pulsing the cells with marker molecules such as amino acids labelled with stable isotopes ((15)N, (13)C). The incorporation of the markers is then imaged with a lateral resolution that can surpass 100 nm. However, secondary ion mass spectrometry cannot identify specific subcellular structures like organelles, and needs to be correlated with a second technique, such as fluorescence imaging. Here, we present a method based on stimulated emission depletion microscopy that provides correlated optical and isotopic nanoscopy (COIN) images. We use this approach to study the protein turnover in different organelles from cultured hippocampal neurons. Correlated optical and isotopic nanoscopy can be applied to a variety of biological samples, and should therefore enable the investigation of the isotopic composition of many organelles and subcellular structures.
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Microscopia de Fluorescência/métodos , Nanotecnologia/métodos , Isótopos , Espectrometria de Massa de Íon Secundário/métodosRESUMO
Previous studies indicate that the release of proteases, including the gelatinase matrix metalloproteinase (MMP)-9, from mature granulocytes plays a crucial role in cytokine-induced hematopoietic stem and progenitor cell (HSPC) mobilization. However, studies with MMP-9-deficient mice revealed that HSPC mobilization was normal in these animals, suggesting that additional proteases must be active at clinically relevant cytokine concentrations. In the present study, we provide evidence that the collagenase MMP-8 is involved in stem cell mobilization. A rapid release of MMP-8 from isolated neutrophil granulocytes can be observed during an in vitro culture. During granulocyte colony-stimulating factor-induced HSPC mobilization, highly elevated serum concentrations of MMP-8 were observed on days 4 to 6 of the mobilization regimen, concomitantly with elevated MMP-9 serum levels and higher numbers of circulating CD34(+) cells. Elevated serum concentrations of both proteases were also found in umbilical cord blood serum. In functional assays, adhesion of HSPC to osteoblasts as an essential component of the endosteal stem cell niche is negatively influenced by MMP-8. The chemokine CXCL12, which is critically involved in stem cell trafficking, can be proteolytically processed by MMP-8 treatment. This degradation has a strong inhibitory influence on HSPC migration. Taken together, our data strongly suggest that MMP-8 can be directly involved in hematopoietic stem cell mobilization and trafficking.
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Células-Tronco Hematopoéticas/enzimologia , Metaloproteinase 8 da Matriz/sangue , Adolescente , Adulto , Medula Óssea/enzimologia , Adesão Celular , Movimento Celular , Células Cultivadas , Quimiocina CXCL12/fisiologia , Proteínas da Matriz Extracelular/metabolismo , Sangue Fetal/enzimologia , Fator Estimulador de Colônias de Granulócitos/fisiologia , Mobilização de Células-Tronco Hematopoéticas , Humanos , Metaloproteinase 8 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Neutrófilos/enzimologia , Transporte Proteico , Proteólise , Adulto JovemRESUMO
Background. Granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA) are autoimmune-mediated diseases characterized by vasculitic inflammation of respiratory tract and kidneys. Clinical observations indicated a strong association between disease activity and serum levels of certain types of autoantibodies (antineutrophil cytoplasm antibodies with cytoplasmic [cANCA in GPA] or perinuclear [pAN CA in MPA] immunofluorescence). Pathologically, both diseases are characterized by severe microvascular endothelial cell damage. Early endothelial outgrowth cells (eEOCs) have been shown to be critically involved in neovascularization under both physiological and pathological condition. Objectives. The principal aims of our study were (i) to analyze the regenerative activity of the eEOC system and (ii) to determine mPR3 and MPO expression in myelo monocytic cells with endothelial characteristics in GPA and MPA patients. Methods. In 27 GPA and 10 MPA patients, regenerative activity blood-derived eEOCs were analyzed using a culture-forming assay. Flk-1(+), CD133(+)/Flk-1(+), mPR3(+), and Flk-1(+)/mPR3(+) myelomonocytic cells were quantified by FACS analysis. Serum levels of Angiopoietin-1 and TNF-α were measured by ELISA. Results. We found reduced eEOC regeneration, accompanied by lower serum levels of Angiopoietin-1 in GPA patients as compared to healthy controls. In addition, the total numbers of Flk-1(+) myelomonocytic cells in the peripheral circulation were decreased. Membrane PR3 expression was significantly higher in total as well as in Flk-1(+) myelomonocytic cells. Expression of MPO was not different between the groups. Conclusions. These data suggest impairment of the eEOC system and a possible role for PR3 in this process in patients suffering from GPA.