Search results for " Exosomes."
showing 10 items of 63 documents
Interleukin 3- receptor targeted exosomes inhibit in vitro and in vivo chronic myelogenous Leukemia cell growth
2017
Despite Imatinib (IM), a selective inhibitor of Bcr-Abl, having led to improved prognosis in Chronic Myeloid Leukemia (CML) patients, acquired resistance and long-term adverse effects is still being encountered. There is, therefore, urgent need to develop alternative strategies to overcome drug resistance. According to the molecules expressed on their surface, exosomes can target specific cells. Exosomes can also be loaded with a variety of molecules, thereby acting as a vehicle for the delivery of therapeutic agents. In this study, we engineered HEK293T cells to express the exosomal protein Lamp2b, fused to a fragment of Interleukin 3 (IL3). The IL3 receptor (IL3-R) is overexpressed in CML…
Exosomal Chaperones and miRNAs in Gliomagenesis: State-of-Art and Theranostics Perspectives
2018
Gliomas have poor prognosis no matter the treatment applied, remaining an unmet clinical need. As background for a substantial change in this situation, this review will focus on the following points: (i) the steady progress in establishing the role of molecular chaperones in carcinogenesis; (ii) the recent advances in the knowledge of miRNAs in regulating gene expression, including genes involved in carcinogenesis and genes encoding chaperones; and (iii) the findings about exosomes and their cargo released by tumor cells. We would like to trigger a discussion about the involvement of exosomal chaperones and miRNAs in gliomagenesis. Chaperones may be either targets for therapy, due to their…
Extracellular vesicles in food: Experimental evidence of their secretion in grape fruits
2017
In the last decade, the number of studies related with extracellular vesicles (EVs) has dramatically grown since their role as key part of intercellular communication has been confirmed. EVs, as transporter of distinct bioactive molecules, can take part in different physiological mechanisms and have been gaining attention as potential tools with a wide range of therapeutic effects. Whereas a high number of studies have been published related to mammalian derived EVs, including products as food source, the existence of EVs in plants still is controversial. Recent descriptions of vesicles derived from edible plants show that they might contain pharmacological active molecules. In this context…
Exosomes as diagnostic and predictive biomarkers in lung cancer
2017
The concept of exosomes has evolved from be considered garbage bags to the demonstration that exosomes could play very interesting roles and functions, from biomarkers detection to the potential of work as drug delivery systems. It has been widely proved that exosomes can contain key molecules important for the tumour development. The current review summarizes the latest investigations developed in the field of predictive exosomal biomarkers. The microRNAs (miRNAs) are the more known molecules due to their amount inside the exosomes and the sensitivity of the techniques available for their study. However, exosomal proteins, RNA and DNA are becoming an interesting and more feasible field of …
Chronic myelogenous leukaemia exosomes modulate bone marrow microenvironment through activation of epidermal growth factor receptor
2016
Abstract Chronic myelogenous leukaemia (CML) is a clonal myeloproliferative disorder. Recent evidence indicates that altered crosstalk between CML and mesenchymal stromal cells may affect leukaemia survival; moreover, vesicles released by both tumour and non‐tumour cells into the microenvironment provide a suitable niche for cancer cell growth and survival. We previously demonstrated that leukaemic and stromal cells establish an exosome‐mediated bidirectional crosstalk leading to the production of IL8 in stromal cells, thus sustaining the survival of CML cells. Human cell lines used are LAMA84 (CML cells), HS5 (stromal cells) and bone marrow primary stromal cells; gene expression and protei…
Exosome-Mediated Signaling in Epithelial to Mesenchymal Transition and Tumor Progression
2018
Growing evidence points to exosomes as key mediators of cell–cell communication, by transferring their specific cargo (e.g., proteins, lipids, DNA and RNA molecules) from producing to receiving cells. In cancer, the regulation of the exosome-mediated intercellular communication may be reshaped, inducing relevant changes in gene expression of recipient cells in addition to microenvironment alterations. Notably, exosomes may deliver signals able to induce the transdifferentiation process known as Epithelial-to-Mesenchymal Transition (EMT). In this review, we summarize recent findings on the role of exosomes in tumor progression and EMT, highlighting current knowledge on exosome-mediated inter…
Cholera Toxin Subunit B for Sensitive and Rapid Determination of Exosomes by Gel Filtration.
2020
We developed a sensitive fluorescence-based assay for determination of exosome concentration. In our assay, Cholera toxin subunit B (CTB) conjugated to a fluorescence probe and a gel filtration technique (size-exclusion chromatography) are used. Exosomal membranes are particularly enriched in raft-forming lipids (cholesterol, sphingolipids, and saturated phospholipids) and in GM1 ganglioside. CTB binds specifically and with high affinity to exosomal GM1 ganglioside residing in rafts only, and it has long been the probe of choice for membrane rafts. The CTB-gel filtration assay allows for detection of as little as 3 × 108 isolated exosomes/mL in a standard fluorometer, which has a sensitivit…
Exosomes as mediators of neuron-glia communication in neuroinflammation
2019
In recent years, a type of extracellular vesicles named exosomes has emerged that play an important role in intercellular communication under physiological and pathological conditions. These nanovesicles (30–150 nm) contain proteins, RNAs and lipids, and their internalization by bystander cells could alter their normal functions. This review focuses on recent knowledge about exosomes as messengers of neuron-glia communication and their participation in the physiological and pathological functions in the central nervous system. Special emphasis is placed on the role of exosomes under toxic or pathological stimuli within the brain, in which the glial exosomes containing inflammatory molecules…
Exosome levels in human body fluids: A tumor marker by themselves?
2016
Despite considerable research efforts, the finding of reliable tumor biomarkers remains challenging and unresolved. In recent years a novel diagnostic biomedical tool with high potential has been identified in extracellular nanovesicles or exosomes. They are released by the majority of the cells and contain detailed molecular information on the cell of origin including tumor hallmarks. Exosomes can be isolated from easy accessible body fluids, and most importantly, they can provide several biomarkers, with different levels of specificity. Recent clinical evidence shows that the levels of exosomes released into body fluids may themselves represent a predictive/diagnostic of tumors, discrimin…
Exosome-associated polysialic acid modulates membrane potentials, membrane thermotropic properties, and raft-dependent interactions between vesicles.
2020
In mammals, polysialic acid (polySia) attached to a small number of transmembrane protein carriers occurs on the surface of plasma membranes of neural, cancer, immune, and placental trophoblast cells. Here, our goal was to demonstrate the presence of polySia on exosomes and its effect on membrane properties. We isolated exosomes and found that polysialylated exosomes in fetal bovine serum originate mostly from placental trophoblasts, while in calf bovine serum, they originate from immune cells. Enzymatic removal of polySia chains from the exosomal surface makes the membrane surface potential more positive, transmembrane potential more negative, and reduces the activation energy for membrane…