Search results for "Microvesicle"

Exosome secretion by Leishmania infantum modulate the chemotactic behavior and cytokinic expression creating an environment permissive for early infe…

2019

Abstract In recent years, several studies demonstrated the role of exosomes in intercellular communications, several Leishmania species belonging to subgenera Leishmania and Viannia have been demonstrated to release exosomes, and their role in parasite-macrophage interactions and in leishmaniasis development has been investigated. However, the release of exosomes by Leishmania infantum has not been studied so far. The aim of this study was to isolate and characterize L. infantum exosomes, and to investigate the biological activity of these exosomes in macrophage cultures. To this end, exosomes were collected from both amastigote and promastigote L. infantum conditioned medium by ultracentri…

2019

Recent studies on extracellular RNA raised awareness that extracellular vesicles (EVs) isolated from cultured cells may co-purify RNAs derived from media supplements such as fetal bovine serum (FBS) confounding EV-associated RNA. Defined culture media supplemented with a range of nutrient components provide an alternative to FBS addition and allow EV-collection under full medium conditions avoiding starvation and cell stress during the collection period. However, the potential contribution of serum-free media supplements to EV-RNA contamination has remained elusive and has never been assessed. Here, we report that RNA isolated from EVs harvested from cells under serum-replacement conditions…

Death Receptor 5 Displayed on Extracellular Vesicles Decreases TRAIL Sensitivity of Colon Cancer Cells

2020

Tumor necrosis factor-related apoptosis inducing ligand (TRAIL) is considered to be a promising antitumor drug because of its selective proapoptotic properties on tumor cells. However, the clinical application of TRAIL is until now limited because of the resistance of several cancer cells, which can occur at various levels in the TRAIL signaling pathway. The role of decoy receptors that can side-track TRAIL, thereby preventing the formation of an activated death receptor, has been extensively studied. In this study, we have focused on extracellular vesicles (EVs) that are known to play a role in cell-to-cell communication and that can be released by donor cells into the medium transferring …

Heterogeneous nuclear ribonucleoprotein C1 may control miR-30d levels in endometrial exosomes affecting early embryo implantation.

2018

Study question Is there a specific mechanism to load the microRNA (miRNA), hsa-miR-30d, into exosomes to facilitate maternal communication with preimplantation embryos? Summary answer The heterogeneous nuclear ribonucleoprotein C1 (hnRNPC1) is involved in the internalization of endometrial miR-30d into exosomes to prepare for its subsequent incorporation into trophectoderm cells. What is known already Our group previously described a novel cell-to-cell communication mechanism involving the delivery of endometrial miRNAs from the maternal endometrium to the trophectoderm cells of preimplantation embryos. Specifically, human endometrial miR-30d is taken up by murine blastocysts causing the ov…

Exosomes in cancer theranostic: Diamonds in the rough

2017

IF 3.306; International audience; During the last 10 years, exosomes, which are small vesicles of 50-200 nm diameter of endosomal origin, have aroused a great interest in the scientific and clinical community for their roles in intercellular communication in almost all physiological and pathological processes. Most cells can potentially release these nanovesicles that share with the parent cell a similar lipid bilayer with transmembrane proteins and a panel of enclosed soluble proteins such as heat shock proteins and genetic material, thus acting as potential nanoshuttles of biomarkers. Exosomes surface proteins allow their targeting and capture by recipient cells, while the exosomes' conte…

Antioxidant role of microvesicles, activated by genistein, in stem cells

2018

Intercellular communication is an essential hallmark of multicellular organisms. Microvesicles (MVs), which are released from and taken up by most types of cells are involved in intercellular communication. The nutrients we ingest from food contact with immune cells in the bloodstream and can promote the formation of MVs. Some foods contain molecules with regulatory activity, such as genistein, a polyphenol found in soy. We aimed to study the effects of MVs released from genistein-treated immune cells on dental pulp stem cells (DPSC). We obtained peripheral blood mononuclear cells (PBMC) from 5 young women (aged 18–25). Cells were cultured and treated with 0.5 μM genistein or 0.01% DMSO as …

Microvesicles released from Giardia intestinalis disturb host-pathogen response in vitro

2017

Giardia intestinalis (G.I), is an anaerobic protozoan and the aetiological agent of giardiasis, a diarrhoea present worldwide and associated with poverty. G.I has a simple life cycle alternating between cyst and trophozoite. Cysts are transmitted orally to the stomach and transform to trophozoites in the intestine by a multifactorial process. Recently, microvesicles (MVs) have been found to be released from a wide range of eukaryotic cells. We have observed a release of MVs during the life cycle of G.I., identifying MVs from active trophozoites and from trophozoites differentiating to the cyst form. The aim of the current work was to investigate the role of MVs from G.I in the pathogenesis …

Chaperonin of Group I: Oligomeric spectrum and biochemical and biological implications

2018

Chaperonins play various physiological roles and can also be pathogenic. Elucidation of their structure, e.g., oligomeric status and post-translational modifications (PTM), is necessary to understand their functions and mechanisms of action in health and disease. Group I chaperonins form tetradecamers with two stacked heptameric rings. The tetradecamer is considered the typical functional complex for folding of client polypeptides. However, other forms such as the monomer and oligomers with smaller number of subunits than the classical tetradecamer, also occur in cells. The properties and functions of the monomer and oligomers, and their roles in chaperonin-associated diseases are still inc…

Engineered exosomes: A new promise for the management of musculoskeletal diseases.

2018

Abstract Background Exosomes are nanovesicles actively secreted by potentially all cell types, including tumour cells, with the primary role of extracellular systemic communication mediators, both at autocrine and paracrine levels, at short and long distances. Recently, different studies have used exosomes as a delivery system for a plethora of different molecules, such as drugs, microRNAs and proteins. This has been made possible thanks to the simplicity in exosomes engineering, their great stability and versatility for applications in oncology as well as in regenerative medicine. Scope of review The aim of this review is to provide information on the state-of-the-art and possible applicat…

Collective properties of viral infectivity

2018

Individual virions typically fail to infect cells. Such decoupling between virions and infectious units is most evident in multicomponent and other segmented viruses, but is also frequent in non-segmented viruses. Despite being a well-known observation, the causes and implications of low single-virion infectivity often remain unclear. In principle, this can originate from intrinsic genetic and/or structural virion defects, but also from host infection barriers that limit early viral proliferation. Hence, viruses may have evolved strategies to increase the per-virion likelihood of establishing successful infections. This can be achieved by adopting spread modes that elevate the multiplicity …