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Biology subjects

Thery, C.

Publications and source records attributed to Thery, C..

8 recordsLinked to original sources

LUCID-EV: a robust and quantitative bioluminescent assay for the detection of EV cytosolic delivery in the absence of VSV-G expression

Extracellular vesicles are key intercellular messengers that modulate the function of target cells by carrying effectors, either at their surface or in their lumen. In the latter case, their action depends on the ability to deliver their content into the cytosol of target cells. How efficiently EVs deliver their content upon interaction with their target cell is thus a central question for understanding the functional impact of this mode of action. To address this question, signal-driven bimolecular interactions between two partners located respectively in the EV lumen and the target cell cytosol have become a widely used strategy to detect the cytosolic delivery EV content. However, the detection of cytosolic delivery with these assays was often tributary to the artificial enhancement of the fusion between EV and cell membranes, through for instance VSV-G fusogenic protein expression. Here we provide a robust and quantitative LUCiferase-based complementation assay (HiBiT/LgBiT), to quantify the Internalization and cytosolic Delivery of EV content: LUCID-EV. By optimizing the signal-to-noise ratio of the assay, the method for loading HiBiT fragment into EVs (fusion to a lipid-binding domain rather than to tetraspanins), and the intracellular position of LgBiT (associated to membranes), we could quantify cytosolic delivery from various non-VSV-G-expressing EVs into target immune dendritic cells. Importantly, this delivery did not involve the acidic late endosomes environment required for VSV-G-dependent EV cytosolic delivery. The limited efficacy of the process highlights the need for highly sensitive assays like the one described here. Further development of the LUCID-EV assay could help identifying EV/target cells pairs with enhanced cytosolic delivery properties and characterize the cellular route for delivery.

cell biology↗

Nano-flow cytometry of single extracellular vesicles reveals subpopulation differences across cell types and pharmacological perturbations

Extracellular vesicles (EVs) are lipid bilayer-enclosed particles released by most cell types, which can transfer signals and cargoes between cells. EVs released by a single donor cell source are increasingly recognized as extremely heterogeneous, in terms of size, intracellular origin, and cargo composition. Analyzing large numbers of EVs at the single vesicle level is therefore the only way to truly decipher their heterogeneity. Here, we developed a reliable pipeline of single EV analysis using a nanoparticle-dedicated flow cytometer, which detects particles and measures their size down to 55 nm in diameter, without the need for vesicle pre-immobilization or fluorescent label. We show that titrating each antibody, eliminating unbound antibodies and using EVs devoid of the analyzed markers as negative controls are required to reliably quantify the proportion of EVs bearing none or any combination of two markers, as well as to measure their sizes. We thus observed, depending on the cell source (human cell lines MDA-MB-231, HeLa, A549), variable proportions of EVs bearing none of the CD9, CD81 and CD63 tetraspanins often used to define EVs, and of single- and double-positive EVs for each of these markers. We also observed CD29 (ITGB1) as a protein detected as frequently on EVs as CD9, while other transmembrane proteins (CD44, SSEA-4, CD98), were detected in a small proportion of EVs, and mostly of relatively large size. Finally, we used this pipeline to uncover differential effects of small molecule drugs on subtypes of EVs, and showed that Homosalate increased the proportion of CD9+/CD63+ EVs while two other drugs, Dipivefrin hydrochloride and Metaraminol bitartrate, instead increased the proportion of CD9-/CD63+ EVs. Overall, nano-flow cytometry allows to reliably quantify proportions of EV subpopulations suggested by bulk analyzes of EV markers, at single EV resolution.

cell biology↗

Harnessing hydrodynamics for high-yield production of extracellular vesicles from stem cells spheroids with specific cargo profiling

This study presents a novel method and device for the hydrodynamic production of extracellular vesicles (EVs) derived from biomimetic multicellular 3D spheroids, enabling high-throughput particle release that is 10 to 20 times higher than in non-stimulated conditions. The device facilitates the formation of spheroids from human mesenchymal stem cells (hMSCs), offering an all-in-one approach for both spheroid generation and EV release. Production times are reduced to just a few hours, with yield further increased by alternating periods of high hydrodynamic flow and spheroid recovery in a sequential production approach. Using this system, we explored the impact of hydrodynamic and starvation conditions on the protein cargo of EVs, identifying distinct protein markers through proteomics. Specifically, hydrodynamic stimulation enriched EVs in plasma membrane-derived and mitochondrial proteins, revealing divergent biogenesis pathways. Importantly, the produced EVs exhibited therapeutic properties, with demonstrated effects in wound healing, angiogenesis, and anti-inflammatory responses, some showing enhanced efficacy under hydrodynamic stimulation.

bioengineering↗

Extracellular Vesicles heterogeneity through the lens of multiomics

Extracellular vesicles (EVs) are heterogenous in size, biogenesis, cargo and function. Beside small EVs, aggressive tumor cells release a population of particularly large EVs, namely large oncosomes (LO). This study provides the first resource of label-free quantitative proteomics of LO and small EVs obtained from distinct cancer cell types (prostate, breast, and glioma). This dataset was integrated with a SWATH Proteomic assay on LO, rigorously isolated from the plasma of patients with metastatic prostate cancer (PC). Proteins enriched in LO, which were identified also at the RNA level, and found in plasma LO significantly correlated with PC progression. Single EV RNA-Seq of the PC cell-derived LO confirmed some of the main findings from the bulk RNA-Seq, providing first evidence that single cell technologies can be successfully applied to EVs. This multiomics resource of cancer EVs can be leveraged for developing a multi-analyte approach for liquid biopsy.

cancer biology↗

Extracellular vesicles and co-isolated endogenous retroviruses differently affect dendritic cells

Cells secrete membrane-enclosed extracellular vesicles (EVs) and non-vesicular nanoparticles (ENPs) that may play a role in intercellular communication. Tumor-derived EVs have been proposed either to induce immune priming of antigen presenting cells, or, to be immuno-suppressive agents promoting tumor immune escape. We suspect that such disparate functions are due to variable composition in EV subtypes and ENPs of the analyzed EV preparations. We aimed to exhaustively characterize the array of secreted EVs and ENPs of murine tumor cell lines. Unexpectedly, we identified virus-like particles (VLPs) from endogenous murine leukemia virus in preparations of EVs produced by tumor cells. We established a robust protocol to separate small (s)EVs from VLPs and ENPs. We compared their protein composition and analyzed their functional interaction with target dendritic cells (DCs). ENPs were poorly captured and did not affect DCs. sEVs specifically induced DC death. A mixed EV/VLP preparation was the most efficient to induce DC maturation and antigen presentation. Our results call for systematic re-evaluation of the respective proportions and functions of non-viral EVs and VLPs produced by tumors and their contribution to anti-tumor immune responses and to tumor progression.

cell biology↗

Detection of tumor-derived extracellular vesicles interactions with immune cells is dependent on EV-labelling methods

Cell-cell communication within the complex tumor microenvironment is critical to cancer progression. Tumor-derived extracellular vesicles (TD-EVs) are key players in this process. They can interact with immune cells and modulate their activity, either suppressing or activating the immune system. Understanding the interactions between TD-EVs and immune cells is essential for understanding immune modulation by cancer cells. Fluorescent labelling of TD-EVs is a method of choice to study such interaction. This work aims to determine the impact of EV labelling methods on the detection of EV interaction and capture by the different immune cell types within human Peripheral Blood Mononuclear Cells (PBMCs), analyzed by imaging flow cytometry and multicolor spectral flow cytometry. EVs released by the triple-negative breast carcinoma cell line MDA-MB-231 were labeled either with the lipophilic dye MemGlow-488 (MG-488), with Carboxyfluorescein diacetate, succinimidyl ester (CFDA-SE), or through expression of a MyrPalm-superFolder GFP (sfGFP) that incorporates into EVs during their biogenesis using a genetically engineered cell line. Our results showed that these different labeling strategies, although analyzed with the same techniques, led to diverging results. While MG-488-labelled EVs incorporate in all cell types, CFSE-labelled EVs are restricted to a minor subset of cells and sfGFP-labelled EVs are mainly detected in CD14+ monocytes which are the main uptakers of EVs and other particles, regardless of the labeling method. Moreover, MG-488-labeled liposomes behaved similarly to MG-488 EVs, highlighting the predominant role of the labelling strategy on the visualization and analysis of TD-EVs uptake by immune cell types. Consequently, the use of different EV labeling methods has to be considered as they can provide complementary information on various types of EV-cell interaction and EV fate.

cell biology↗

Homosalate boosts the release of tumor-derived Extracellular Vesicles with anti-anoikis properties

Eukaryotic cells, including cancer cells, secrete highly heterogeneous populations of extracellular vesicles (EVs). EVs could have different subcellular origin, composition and functional properties, but tools to distinguish between EV subtypes are scarce. Here, we tagged CD63- or CD9-positive EVs secreted by triple negative breast cancer cells with Nanoluciferase enzyme, to set-up a miniaturized method to quantify secretion of these two EV subtypes directly in the supernatant of cells. We performed a cell-based high-content screening to identify clinically-approved drugs able to affect EV secretion. One of the identified hits is Homosalate, an anti-inflammatory drug found in sunscreens which robustly increased EVs release. Comparing EVs induced by Homosalate with those induced by Bafilomycin A1, we discovered that: 1) the two drugs act on EVs generated in distinct subcellular compartments and 2) EVs released upon treatment with Homosalate, but not with Bafilomycin A1, conferred anti-anoikis properties to another recipient tumor cell line. In conclusion, we identified a new drug modifying EV release and demonstrated that under influence of different drugs, triple negative breast cancer cells release EV subpopulations from different subcellular origins harboring distinct functional properties.

cell biology↗

Specificities of exosome versus small ectosome secretion revealed by live intracellulartracking and synchronized extracellular vesicle release of CD9 and CD63

Despite their important and multiple roles in intercellular communications, the different populations of extracellular vesicles (EVs) and their secretion mechanisms are not fully characterized yet. In particular, how and to what extent EVs form either as intraluminal vesicles of endocytic compartments (exosomes), or at the plasma membrane (ectosomes) remains unclear. We followed in HeLa cells the intracellular trafficking of the EV markers CD9 and CD63 from the endoplasmic reticulum to their residency compartment and identified transient co-localization both at the plasma membrane (PM) and in endosomes, before they finally segregate. CD9 was more abundantly released in EVs than CD63. However, when forcing expression of CD63 at the PM, by mutating its lysosome-addressing motive, its secretion in EVs was increased. Thus, in HeLa cells, small ectosomes are more prominently released than exosomes. By comparative proteomic analysis, we identified a few surface proteins likely specific of either exosomes (e.g. LAMP1) or ectosomes (e.g. BSG, SLC3A2), based on their known intracellular location in lysosomes or the PM, and on the different effects on their release of Bafilomycin A1, a drug that neutralizes endosomal pH. Our work sets the path for molecular and functional discrimination of exosomes and small ectosomes in any cell type.

cell biology↗