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Abdominal aortic aneurysm (AAA) is a frequent aortic disease. If the diameter of the aorta is larger than 5 cm, an open surgical repair (OSR) or an endovascular aortic repair (EVAR) are recommended. To prevent possible complications (i.e., endoleaks), EVAR-treated patients need to be monitored for 5 years following the intervention, using computed tomography angiography (CTA). However, this radiological method involves high radiation exposure in terms of CTA/year. In such a context, the study of peripheral-blood-circulating extracellular vesicles (pbcEVs) has great potential to identify biomarkers for EVAR complications. We analyzed several phenotypes of pbcEVs using polychromatic flow cytometry in 22 patients with AAA eligible for EVAR. From each enrolled patient, peripheral blood samples were collected at AAA diagnosis, and after 1, 6, and 12 months following EVAR implantation, i.e. during the diagnostic follow-up protocol. Patients developing an endoleak displayed a significant decrease in activated-platelet-derived EVs between the baseline condition and 6 months after EVAR intervention. Furthermore, we also observed, that 1 month after EVAR implantation, patients developing an endoleak showed higher concentrations of activated-endothelial-derived EVs than patients who did not develop one, suggesting their great potential as a noninvasive and specific biomarker for early identification of EVAR complications.
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Aneurisma da Aorta Abdominal , Implante de Prótese Vascular , Procedimentos Endovasculares , Humanos , Correção Endovascular de Aneurisma , Implante de Prótese Vascular/efeitos adversos , Endoleak/etiologia , Endoleak/cirurgia , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/métodos , Aneurisma da Aorta Abdominal/cirurgia , Aneurisma da Aorta Abdominal/etiologia , Resultado do Tratamento , Estudos Retrospectivos , Fatores de RiscoRESUMO
Extracellular vesicles act as shuttle vectors or signal transducers that can deliver specific biological information and have progressively emerged as key regulators of organized communities of cells within multicellular organisms in health and disease. Here, we survey the evolutionary origin, general characteristics, and biological significance of extracellular vesicles as mediators of intercellular signaling, discuss the various subtypes of extracellular vesicles thus far described and the principal methodological approaches to their study, and review the role of extracellular vesicles in tumorigenesis, immunity, non-synaptic neural communication, vascular-neural communication through the blood-brain barrier, renal pathophysiology, and embryo-fetal/maternal communication through the placenta.
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Biomarcadores/metabolismo , Doença/genética , Vesículas Extracelulares/metabolismo , Comunicação Celular , Vesículas Extracelulares/genética , Predisposição Genética para Doença , Humanos , Imunidade , Transdução de SinaisRESUMO
Extracellular vesicles (EVs) actively participate in inter-cellular crosstalk and have progressively emerged as key players of organized communities of cells within multicellular organisms in health and disease. For these reasons, EVs are attracting the attention of many investigators across different biomedical fields. In this scenario, the possibility to study specific placental-derived EVs in the maternal peripheral blood may open novel perspectives in the development of new early biomarkers for major obstetric pathological conditions. Here we reviewed the involvement of EVs in feto-maternal crosstalk mechanisms, both in physiological and pathological conditions (preeclampsia, fetal growth restriction, preterm labor, gestational diabetes mellitus), also underlining the usefulness of EV characterization in maternal-fetal medicine.
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Diabetes Gestacional/metabolismo , Vesículas Extracelulares/metabolismo , Retardo do Crescimento Fetal/metabolismo , Troca Materno-Fetal , Placenta/metabolismo , Pré-Eclâmpsia/metabolismo , Biomarcadores/sangue , Biomarcadores/metabolismo , Feminino , Humanos , GravidezRESUMO
Extracellular vesicles (EVs) play a crucial role in the intercellular crosstalk. Mesenchymal stem cell-derived EVs (MSC-EVs), displaying promising therapeutic roles, contribute to the strong rationale for developing EVs as an alternative therapeutic option. EV analysis still represents one of the major issues to be solved in order to translate the use of MSC-EV detection in clinical settings. Even if flow cytometry (FC) has been largely applied for EV studies, the lack of consensus on protocols for FC detection of EVs generated controversy. Standard FC procedures, based on scatter measurements, only allows the detection of the "tip of the iceberg" of all EVs. We applied an alternative FC approach based on the use of a trigger threshold on a fluorescence channel. The EV numbers obtained by the application of the fluorescence triggering resulted significantly higher in respect to them obtained from the same samples acquired by placing the threshold on the side scatter (SSC) channel. The analysis of EV concentrations carried out by three different standardized flow cytometers allowed us to achieve a high level of reproducibility (CV < 20%). By applying the here-reported method highly reproducible results in terms of EV analysis and concentration measurements were obtained.
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Vesículas Extracelulares/metabolismo , Citometria de Fluxo/métodos , Células-Tronco Mesenquimais/citologia , Animais , Células Cultivadas , Difusão Dinâmica da Luz , Separação Imunomagnética , Células-Tronco Mesenquimais/metabolismoRESUMO
Extracellular vesicles (EVs) are released by shedding during different physiological processes and are increasingly thought to be new potential biomarkers. However, the impact of pre-analytical processing phases on the final measurement is not predictable and for this reason, the translation of basic research into clinical practice has been precluded. Here we have optimized a simple procedure in combination with polychromatic flow cytometry (PFC), to identify, classify, enumerate, and separate circulating EVs from different cell origins. This protocol takes advantage of a lipophilic cationic dye (LCD) able to probe EVs. Moreover, the application of the newly optimized PFC protocol here described allowed the obtainment of repeatable EVs counts. The translation of this PFC protocol to fluorescence-activated cell sorting allowed us to separate EVs from fresh peripheral blood samples. Sorted EVs preparations resulted particularly suitable for proteomic analyses, which we applied to study their protein cargo. Here we show that LCD staining allowed PFC detection and sorting of EVs from fresh body fluids, avoiding pre-analytical steps of enrichment that could impact final results. Therefore, LCD staining is an essential step towards the assessment of EVs clinical significance.
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Biomarcadores , Vesículas Extracelulares/metabolismo , Citometria de Fluxo , Biópsia Líquida , Animais , Citometria de Fluxo/métodos , Humanos , Biópsia Líquida/métodos , Tamanho da Partícula , Plasma , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Extracellular vesicles (EVs), referred as membranous vesicles released into body fluids from all cell types, represent a novel model to explain some aspects of the inter-cellular cross talk. It has been demonstrated that the EVs modify the phenotype of target cells, acting through a large spectrum of mechanisms. In the central nervous system, the EVs are responsible of the wide range of physiological processes required for normal brain function and neuronal support, such as immune signaling, cellular proliferation, differentiation, and senescence. Growing evidences link the EV functions to the pathogenic machinery of the neurological diseases, contributing to the disease progression and spreading. Extracellular vesicles are involved in the brain injury by multimodal ways; they propagate inflammation across the blood brain barrier (BBB), mediate neuroprotection and modulate regenerative processes. For these reasons, extracellular vesicles represent a promising biomarker in neurological disorders as well as an interesting starting point for the development of novel therapeutic strategies. Herein, we review the role of the EVs in the pathogenesis of neurological disease, discussing their potential clinical applications.
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Bacteria generate membrane vesicles, which are structures known as extracellular vesicles (EVs), reported to be involved in different pathogenic mechanisms, as it has been demonstrated that EVs participate in biofilm formation, cell-to-cell communication, bacteria-host interactions, and nutrients supply. EVs deliver nucleic acids, proteins, and polysaccharides. It has been reported that Helicobacter pylori (H. pylori) and Lactobacillus reuteri (L. reuteri), of both planktonic and biofilm phenotypes, produce EVs carrying extracellular DNA (eDNA). Here, we used polychromatic flow cytometry (PFC) to identify, enumerate, and characterize EVs as well as the eDNA-delivering EV compartment in the biofilm and planktonic phenotypes of H.pylori ATCC 43629 and L. reuteri DSM 17938. Biofilm formation was demonstrated and analyzed by fluorescence microscopy, using a classical live/dead staining protocol. The enumeration of EVs and the detection of eDNA-associated EVs were performed by PFC, analyzing both whole samples (cells plus vesicles) and EVs isolated by ultracentrifugation confirm EVs isolated by ultracentrifugation. PFC analysis was performed relying on a known-size beaded system and a mix of three different fluorescent tracers. In detail, the whole EV compartment was stained by a lipophilic cationic dye (LCD), which was combined to PKH26 and PicoGreen that selectively stain lipids and DNA, respectively. Fluorescence microscopy results displayed that both H. pylori and L. reuteri produced well-structured biofilms. PFC data highlighted that, in both detected bacterial species, biofilms produced higher EVs counts when paralleled to the related planktonic phenotypes. Furthermore, the staining with PicoGreen showed that most of the generated vesicles were associated with eDNA. These data suggest that the use of PFC, set according to the parameters here described, allows for the study of the production of eDNA-associated EVs in different microbial species in the same or several phases of growth, thus opening new perspectives in the study of microbial derived EVs in clinical samples.
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Membrana Celular/química , DNA Bacteriano/análise , Vesículas Extracelulares/química , Citometria de Fluxo , Helicobacter pylori/química , Limosilactobacillus reuteri/químicaRESUMO
Circulating endothelial cells (CEC) and their progenitors (EPC) are restricted subpopulations of peripheral blood (PB), cord blood (CB), and bone marrow (BM) cells, involved in the endothelial homeostasis maintenance. Both CEC and EPC are thought to represent potential biomarkers in several clinical conditions involving endothelial turnover/remodeling. Although different flow cytometry methods for CEC and EPC characterization have been published so far, none of them have reached consistent conclusions, therefore consensus guidelines with respect to CEC and EPC identification and quantification need to be established. Here, we have carried out an in depth investigation of CEC and EPC phenotypes in healthy PB, CB and BM samples, by optimizing a reliable polychromatic flow cytometry (PFC) panel. Results showed that the brightness of CD34 expression on healthy PB and CB circulating cells represents a key benchmark for the identification of CEC (CD45neg/CD34bright/CD146pos) respect to the hematopoietic stem cell (HSC) compartment (CD45dim/CD34pos/CD146neg). This approach, combined with a dual-platform counting technique, allowed a sharp CEC enumeration in healthy PB (n = 38), and resulting in consistent CEC counts with previously reported data (median = 11.7 cells/ml). In parallel, by using rigorous PFC conditions, CD34pos/CD45dim/CD133pos/VEGFR2pos EPC were not found in any healthy PB or CB sample, since VEGFR2 expression was never detectable on the surface of CD34pos/CD45dim/CD133pos cells. Notably, the putative EPC phenotype was observed in all analyzed BM samples (n = 12), and the expression of CD146 and VEGFR2, on BM cells, was not restricted to the CD34bright compartment, but also appeared on the HSC surface. Altogether, our findings suggest that the previously reported EPC antigen profile, defined by the simultaneous expression of VEGFR2 and CD133 on the surface of CD45dim/CD34pos cells, should be carefully re-evaluated and further studies should be conducted to redefine EPC features in order to translate CEC and EPC characterization into clinical practice.
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Antígeno AC133/genética , Células Progenitoras Endoteliais/citologia , Sangue Fetal/citologia , Citometria de Fluxo/normas , Imunofenotipagem/normas , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Antígeno AC133/imunologia , Adolescente , Adulto , Idoso , Antígenos CD34/genética , Antígenos CD34/imunologia , Benchmarking , Antígeno CD146/genética , Antígeno CD146/imunologia , Contagem de Células , Células Progenitoras Endoteliais/imunologia , Feminino , Sangue Fetal/imunologia , Corantes Fluorescentes/química , Expressão Gênica , Voluntários Saudáveis , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/imunologia , Humanos , Antígenos Comuns de Leucócito/genética , Antígenos Comuns de Leucócito/imunologia , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/imunologiaRESUMO
BACKGROUND/AIMS: Extracellular GTP is able to modulate some specific functions in neuron, glia and muscle cell models as it has been demonstrated over the last two decades. In fact, extracellular GTP binds its specific plasma membrane binding sites and induces signal transduction via [Ca(2+)]i increase. We demonstrate, for the first time, that extracellular GTP is able to modulate cell swelling in M1-CCD cortical collecting duct epithelial cells via upregulation of aquaporin 5 (AQP5) expression. METHODS: We used videoimaging, immunocitochemistry, flow cytometry, confocal techniques, Western blotting and RT-PCR for protein and gene expression analysis, respectively. RESULTS: We demonstrate that AQP5 mRNA is up-regulated 7 h after the GTP exposure in the cell culture medium, and its protein level is increased after 12-24 h. We show that AQP5 is targeted to the plasma membrane of M1-CCD cells, where it facilitates cell swelling, and that the GTP-dependent AQP5 up-regulation occurs via [Ca(2+)]i increase. Indeed, GTP induces both oscillating and transient [Ca(2+)]i increase, and specifically the oscillating kinetic appears to be responsible for blocking cell cycle in the S-phase while the [Ca(2+)]i influx, with whatever kinetic, seems to be responsible for inducing AQP5 expression. CONCLUSION: The role of GTP as a regulator of AQP5-mediated water transport in renal cells is of great importance in the physiology of renal epithelia, due to its possible physiopathological implications. GTP-dependent AQP5 expression could act as osmosensor. In addition, the data presented here suggest that GTP might play the same role in other tissues where rapid water transport is required for cell volume regulation and maintenance of the homeostasis.
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Aquaporina 5/biossíntese , Membrana Celular/metabolismo , Células Epiteliais/metabolismo , Guanosina Trifosfato/farmacologia , Túbulos Renais Coletores/metabolismo , Regulação para Cima/efeitos dos fármacos , Animais , Sinalização do Cálcio/efeitos dos fármacos , Linhagem Celular , Células Epiteliais/citologia , Túbulos Renais Coletores/citologia , CamundongosRESUMO
Breast cancer represents the second cause of death in the European female population. The lack of specific therapies together with its high invasive potential are the major problems associated to such a tumor. In the last three decades platinum-based drugs have been considered essential constituents of many therapeutic strategies, even though with side effects and frequent generation of drug resistance. These drugs have been the guide for the research, in last years, of novel platinum and ruthenium based compounds, able to overcome these limitations. In this work, ruthenium and platinum based phthalocyanines were synthesized through conventional techniques and their antiproliferative and/or cytotoxic actions were tested. Normal mammary gland (MCF10A) and several models of mammarian carcinoma at different degrees of invasiveness (BT474, MCF-7 and MDA-MB-231) were used. Cells were treated with different concentrations (5-100 µM) of the above reported compounds, to evaluate toxic concentration and to underline possible dose-response effects. The study included growth curves made by trypan blue exclusion test and scratch assay to study cellular motility and its possible negative modulation by phthalocyanine. Moreover, we investigated cell cycle and apoptosis through flow cytometry and AMNIS Image Stream cytometer. Among all the tested drugs, tetrasulfonated phthalocyanine of platinum resulted to be the molecule with the best cytostatic action on neoplastic cell lines at the concentration of 30 µM. Interestingly, platinum tetrasulfophtalocyanine, at low doses, had no antiproliferative effects on normal cells. Therefore, such platinum complex, appears to be a promising drug for mammarian carcinoma treatment.
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Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Indóis/farmacologia , Compostos Organoplatínicos/farmacologia , Água/química , Antineoplásicos/química , Antineoplásicos/metabolismo , Ciclo Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Indóis/química , Indóis/metabolismo , Células MCF-7 , Compostos Organoplatínicos/química , Compostos Organoplatínicos/metabolismo , SolubilidadeRESUMO
BACKGROUND: It has been demonstrated that the umbilical cord matrix, represented by the Wharton's Jelly (WJ), contains a great number of mesenchymal stem cells (MSCs), characterized by the expression of specific MSCs markers, shared by both human and animal models. The easy access to massive WJ amount makes it an attractive source of MSCs for cell-based therapies. However, as in other stem cell models, a deeper investigation of WJ-derived MSCs (WJ-MSCs) biological properties, probably modulated by their prolonged expansion and fast growth abilities, is required before their use in clinical settings. In this context, in order to analyze specific gene expression modifications occurring in WJ-MSCs, along with their culture prolongation, we investigated the transcriptomic profiles of WJ-MSCs after 4 and 12 passages of in vitro expansion by microarray analysis. RESULTS: Hierarchical clustering analysis of the data set originated from a total of 6 experiments revealed that in vitro expansion of WJ-MSCs up to 12 passages promote selective over-expression of 157 genes and down-regulation of 440 genes compared to the 4th passage. IPA software analysis of the biological functions related to the identified sets of genes disclosed several transcripts related to inflammatory and cell stress response, cell proliferation and maturation, and apoptosis. CONCLUSIONS: Taken together, these modifications may lead to an impairment of both cell expansion ability and resistance to apoptosis, two hallmarks of aging cells. In conclusion, results provided by the present study suggest the need to develop novel culture protocols able to preserve stem cell plasticity.
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Expressão Gênica , Células-Tronco Mesenquimais/metabolismo , Transcriptoma , Geleia de Wharton/citologia , Técnicas de Cultura de Células , Diferenciação Celular , Células Cultivadas , Análise por Conglomerados , HumanosRESUMO
Phospholipase Cγ1 (PLCγ1) is highly expressed in several tumors. We have previously reported that both stable and inducible PLCγ1 down-regulation resulted in an almost complete inhibition of breast cancer-derived experimental lung metastasis formation. The aim of our study is to evaluate the association between the expression of PLCγ1 and of PLCγ1 phosphorylated at Tyr1253 (PLCγ1-pY1253) and at Tyr783 (PLCγ1-pY783) with the clinical outcome of patients with node negative, T1/T2 breast cancers. The study groups consisted of 292 (training set) and 122 (validation set) patients presenting with primary unilateral breast carcinoma (T1-T2), with no evidence of nodal involvement and distant metastases. PLCγ1, PLCγ1-pY1253 and PLCγ1-pY783 protein expression were assessed by immunohistochemistry on tissue microarrays and the results correlated with the clinical data using Kaplan-Meier curves and multivariate Cox regression analysis. Tumor cells while expressing variable proportions of cytoplasmic PLCγ1, express PLCγ1-pY1253 and PLCγ1-pY783 predominantly in the nucleus. High expression of PLCγ1, and of its activated forms, is associated with a worse clinical outcome in terms of incidence of distant metastases, and not of local relapse in T1-T2, N0 breast cancer patients undergone adjuvant chemotherapy. PLCγ1 over-expression appears to be a reliable predictive surrogate marker of development of metastases. Thus, targeting PLCγ1 pathways might represent a potential therapeutic approach for the prevention of metastatic disease in breast cancer.
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Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/enzimologia , Fosfolipase C gama/biossíntese , Idoso , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Quimioterapia Adjuvante , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Fosfolipase C gama/genética , Fosfolipase C gama/metabolismo , Fatores de RiscoRESUMO
Extracellular vesicles (EVs) are a class of circulating entities that are involved in intercellular crosstalk mechanisms, participating in homeostasis maintenance, and diseases. Celiac disease is a gluten-triggered immune-mediated disorder, characterized by the inflammatory insult of the enteric mucosa following local lymphocytic infiltration, resulting in villous atrophy. The goal of this research was the assessment and characterization of circulating EVs in celiac disease patients, as well as in patients already on an adequate gluten-free regimen (GFD). For this purpose, a novel and validated technique based on polychromatic flow cytometry that allowed the identification and enumeration of different EV sub-phenotypes was applied. The analysis evidenced that the total, annexin V+, leukocyte (CD45+), and platelet (CD41a+) EV counts were significantly higher in both newly diagnosed celiac disease patients and patients under GFD compared with the healthy controls. Endothelial-derived (CD31+) and epithelial-derived (EpCAM+) EV counts were significantly lower in subjects under gluten exclusion than in celiac disease patients, although EpCAM+ EVs maintained higher counts than healthy subjects. The numbers of EpCAM+ EVs were a statistically significant predictor of intraepithelial leukocytes (IEL). These data demonstrate that EVs could represent novel and potentially powerful disease-specific biomarkers in the context of celiac disease.
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Doença Celíaca , Vesículas Extracelulares , Humanos , Doença Celíaca/diagnóstico , Molécula de Adesão da Célula Epitelial , Glutens , Intestino Delgado , Dieta Livre de GlútenRESUMO
OBJECTIVE: Extracellular Vesicles (EVs) are cell-derived particles released during different pathophysiological processes, circulating in many body fluids and mediating the inter-cellular crosstalk. We have analyzed, for the first time, different EV phenotypes and concentrations in the peripheral blood of uncomplicated pregnant women. STUDY DESIGN: In this prospective case-control study, uncomplicated singleton pregnant women at term (N = 59) and aged matched non-pregnant women (N = 21) were enrolled. Freshly drowned peripheral blood samples were stained for flow cytometry analyses of EVs. RESULTS: EVs derived from platelets, leukocytes, endothelial and epithelial cells were identified and counted. Platelet-derived EVs were higher in pregnant compared to non-pregnant women, both in terms of absolute counts (2064.4 ± 1156.3 vs 701.1 ± 378.8; p < 0.0001) and percentages (27.6 ± 17.2 vs 10.7 ± 5.9; p < 0.0001). The opposite pattern was observed both for concentrations of endothelial-EV counts (525.8 ± 499.6 vs 844.7 ± 652.9; p = 0.007) and percentages (6.1 ± 5.5 vs 11.8 ± 8.0; p < 0.0001) and leukocyte-derived EV percentages (10.2 ± 7.4 vs 17.9 ± 11.2; p = 0.002) EVs. CONCLUSIONS: Uncomplicated pregnancies are characterized by a specific EV signature. These cell-derived particles may therefore represent promising biomarkers of different pathological conditions complicating pregnancies, such as preeclampsia or preterm birth.
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Vesículas Extracelulares , Nascimento Prematuro , Recém-Nascido , Humanos , Gravidez , Feminino , Estudos de Casos e Controles , Biópsia Líquida , PlaquetasRESUMO
Colorectal cancer (CRC) is one of the most incident and lethal malignancies worldwide. Recent treatment advances prolonged survival in patients with metastatic colorectal cancer (mCRC). However, there are still few biomarkers to guide clinical management and treatment selection in mCRC. In this study, we applied an optimized flow cytometry protocol for EV identification, enumeration, and subtyping in blood samples of 54 patients with mCRC and 48 age and sex-matched healthy controls (HCs). The overall survival (OS) and overall response rate (ORR) were evaluated in mCRC patients enrolled and treated with a first line fluoropyrimidine-based regimen. Our findings show that patients with mCRC presented considerably higher blood concentrations of total EVs, as well as CD133+ and EPCAM+ EVs compared to HCs. Overall survival analysis revealed that increased blood concentrations of total EVs and CD133+ EVs before treatment were significantly associated with shorter OS in mCRC patients (p = 0.001; and p = 0.0001, respectively). In addition, we observed a correlation between high blood levels of CD133+ EVs at baseline and reduced ORR to first-line systemic therapy (p = 0.045). These findings may open exciting perspectives into the application of novel blood-based EV biomarkers for improved risk stratification and optimized treatment strategies in mCRC.
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Vav1 plays an important role in the all-trans retinoic acid (ATRA)-induced completion of the differentiation program of acute promyelocytic leukemia (APL)-derived cells, in which it strengthens the drug effects and is involved in the regulation of maturation-related proteins, such as the CD11b surface antigen. In both myeloid and lymphoid cells, accumulating data attribute to the multidomain protein Vav1 a functional relevance in the control of gene expression, by direct interaction with chromatin remodeling and/or transcriptional proteins. The present study provides evidence that, in the APL-derived NB4 cell line, Vav1 and the transcription factor PU.1 cooperate in regulating the ATRA-induced CD11b expression. Both chromatin immunoprecipitation (ChIP) experiments and electrophoretic mobility shift assays (EMSA) indicate that Vav1 and PU.1 are recruited to CD11b promoter. Even if the two proteins may participate in diverse protein/DNA complexes, the amounts of complexes including PU.1 seem to be dependent on the interaction of this transcription factor with tyrosine-phosphorylated Vav1. The reported data suggest that the ATRA-induced increase of Vav1 expression and tyrosine phosphorylation may be involved in recruiting PU.1 to its consensus sequence on the CD11b promoter and, ultimately, in regulating CD11b expression during the late stages of neutrophil differentiation of APL-derived promyelocytes.
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Antígeno CD11b/genética , Diferenciação Celular/fisiologia , Células Precursoras de Granulócitos/metabolismo , Regiões Promotoras Genéticas/fisiologia , Proteínas Proto-Oncogênicas c-vav/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Transativadores/metabolismo , Tretinoína/farmacologia , Antígeno CD11b/metabolismo , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Núcleo Celular/metabolismo , Imunoprecipitação da Cromatina , DNA/genética , DNA/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Regulação Neoplásica da Expressão Gênica/fisiologia , Células Precursoras de Granulócitos/citologia , Células Precursoras de Granulócitos/efeitos dos fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Leucemia Promielocítica Aguda/patologia , Neutrófilos/citologia , Neutrófilos/metabolismo , Fosforilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Ligação Proteica/fisiologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-vav/genética , RNA Interferente Pequeno/genética , Estilbenos/farmacologia , Quinase Syk , Transativadores/genéticaRESUMO
BACKGROUND: Extracellular vesicles, released by cell pullulation, are surrounded by a phospholipid bilayer and carry proteins as well and genetic material. It has been shown that extracellular vesicles mediate intercellular communication in several conditions, such as inflammation, immunodeficiency, tumor growth, and viral infections. Here, we analyzed circulating levels of extracellular vesicles in order to clarify their role in chronic inflammation mechanisms characterizing HIV patients. METHODS: We analyzed and subtyped circulating levels of extracellular vesicles, through a recently developed flow cytometry method. In detail, endothelial-derived extracellular vesicles (CD31+/CD41a-/CD45-, EMVs), extracellular vesicles stemming from leukocytes (CD45+, LMVs) and platelets (CD41a+/CD31+) were identified and enumerated. Moreover, we analyzed the extracellular vesicle protein cargo with proteomic analysis. RESULTS: Circulating levels of total extracellular vesicles, EMVs and LMVs were significantly lower in the HIV+ patients than in healthy subjects, whereas platelet-derived extracellular vesicles resulted higher in patients than in the healthy population. Proteomic analysis showed the upregulation of gammaIFN and IL1α, and down-regulation of OSM, NF-kB, LIF, and RXRA signaling resulted activated in this patients. CONCLUSION: These data demonstrate, for the first time that HIV infection induces the production of extracellular vesicles containing mediators that possibly feed the chronic inflammation and the viral replication. These two effects are connected as the inflammation itself induces the viral replication. We, therefore, hypothesize that HIV infection inhibits the production of extracellular vesicles that carry anti-inflammatory molecules.
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Vesículas Extracelulares , Infecções por HIV , Plaquetas , Humanos , Inflamação , ProteômicaRESUMO
Immune checkpoint inhibitors (ICIs) induce durable clinical responses only in a subset of advanced non-small cell lung cancer (NSCLC) patients. There is a need to identify mechanisms of ICI resistance and immunotherapy biomarkers to improve clinical benefit. In this study, we evaluated the prognostic and predictive value of circulating endothelial and leukocyte-derived extracellular vesicles (EV) in patients with advanced NSCLC treated with anti-PD-1/PD-L1 agents. In addition, the relationship between total blood circulating EV proteome and response to ICIs was investigated. An optimized flow cytometry method was employed for the identification and subtyping of blood circulating EVs in 59 patients with advanced NSCLC. Blood samples were collected from patients receiving anti-PD-1/PD-L1 inhibitors (n = 31) or chemotherapy (n = 28). An exploratory proteomic analysis of sorted blood EVs was conducted in a subset of patients. Our results show that a low blood concentration of circulating endothelial-derived EVs before treatment was strongly associated to longer overall survival (p = 0.0004) and higher disease control rate (p = 0.045) in patients treated with ICIs. Interestingly, shotgun proteomics revealed that EVs of responders to anti-PD-1 therapy had a specific protein cargo before treatment. In addition, EV protein cargo was specifically modulated during immunotherapy. We identified a previously unknown association between circulating endothelial-derived extracellular vesicle concentration and immunotherapy-related clinical outcomes. We also observed differences in circulating extracellular vesicle proteome according to anti-PD-1-based treatment response in NSCLC patients. Overall, these results may contribute to the identification of novel circulating biomarkers for rational immunotherapy approaches in patients affected by NSCLC.
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The clinical progression of B cell chronic lymphocytic leukemia (CLL) is associated with immune cell dysfunction and a strong decrease of miR-181b-5p (miR-181b), promoting the death of CLL cells. Here we investigated whether the reduction of miR-181b impairs the immune response in CLL. We demonstrate that activated CD4+ T cells increase miR-181b expression in CLL through CD40-CD40L signaling, which enhances the maturation and activity of cytotoxic T cells and, consequently, the apoptotic response of CLL cells. The cytotoxic response is facilitated by a depletion of the anti-inflammatory cytokine interleukin 10, targeted by miR-181b. In vivo experiments in NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ mice confirmed that miR-181b promotes the apoptotic death of CLL cells only when functional T cells are restored. Overall, our findings suggest that the reinstatement of miR-181b in CLL cells could be an exploitable adjuvant therapeutic option for the treatment of CLL.
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In Italy, recent legislation (Law No. 10/2020) has tuned regulations concerning the donation of one's postmortem body and tissues for study, training, and scientific research purposes. This study discusses several specific issues to optimise the applicability and effectiveness of such an important, novel regulatory setting. Critical issues arise concerning the learners, the type of training and teaching activities that can be planned, the position of academic anatomy institutes, the role of family members in the donation process, the time frame of the donation process, the eligibility of partial donation, or the simultaneous donation of organs and tissues to patients awaiting transplantation. In particular, a universal time limit for donations (i.e., one year) makes it impossible to plan the long-term use of specific body parts, which could be effectively preserved for the advanced teaching and training of medical students and surgeons. The abovementioned conditions lead to the limited use of corpses, thus resulting in the inefficiency of the whole system of body donation. Overall, the donors' scope for the donation of their body could be best honoured by a more flexible and tuneable approach that can be used on a case-by-case basis. Furthermore, it is deemed necessary to closely monitor the events scheduled for corpses in public nonacademic institutions or private enterprises. This paper presents useful insights from Italian anatomists with the hope of providing inspiration for drafting the regulations. In conclusion, this paper focuses on the critical issues derived from the recently introduced Italian law on the donation and use of the body after death and provides suggestions to lawmakers for future implementations.