Suchergebnisse

Acknowledgments: Transmission electron microscopy was performed at the "Centro de Instrumentación Científica" of the "Universidad de Granada". Dynamic light scattering was performed at the "Laboratorio de Polímeros" of the School of Chemistry, "Universidad Nacional" and atomic force microscopy imaging was performed at the Physics Department of the same university. Proteomic analyses were performed at the "Instituto Clodomiro Picado", of the "Universidad de Costa Rica". Special thanks to Oscar Rojas Carrillo for allowing the access to the equipment and for his methodological support during the dynamic light scattering analyses and Desire Arrieta Murillo and Jocelyn Cortés Espínola for the technical support during the atomic force microscopy analyses. G.S.-A. wants to thank "Plan de Mejoramiento Institucional UNA BM-04", Consejo Nacional de Rectores (FEES-CONARE) and the "Vicerrectoría de Investigación" of Universidad Nacional de Costa Rica for funding for equipment. ; Data Availability Statement: Mass spectrometry raw files of the data presented in this work are available from the authors upon reasonable request. ; Funding: This research was funded by "Vicerrectoría de Investigación" of the "Universidad de Costa Rica", by supporting the research projects C-1061: "Caracterización de antígenos de excreción/ secreción y antígenos somáticos en amebas de vida libre mediante empleo de anticuerpos policlonales producidos en roedores" and C-2600: "Secreción de vesículas extracelulares por Naegleria fowleri y evaluación de su potencial rol inmunomodulador en un modelo in vitro". ; Institutional Review Board Statement: The use of animals was performed following the institutional guidelines (Spanish government regulations (Real Decreto RD1201/05)) and the guidelines of the European Union (European Directive 2010/63/EU). These experiments were approved by the Ethical Committee of the University of Granada (235-CEEA-OH-2018) and by the authorities of the Regional Government of Andalucía (JJAA) (number 12/11/2017/162). ...

Altres ajuts: this work was supported in part by Fundació La Marató de TV3 (201516-10, 201502-30). MM-T is sponsored by the PERIS (SLT002/16/00234) from the Generalitat de Catalunya; FB is a researcher from Fundació Institut de Recerca en Ciències de la Salut Germans Trias i Pujol, supported by the Health Department of the Catalan Government (Direcció General de Recerca i Innovació, Department Salut, Generalitat de Catalunya) and MF is funded by the Catalan Health Department (Generalitat de Catalunya) contract PERIS (SLT002/16/00069). ; Mesenchymal stem or stromal cells (MSC) have proven immunomodulatory properties toward B cell activation and induce regulatory B cells (Breg), through a dual mechanism of action that relies both on cell contact and secreted factors. One of them are MSC-derived extracellular vesicles (EVs), membrane nanovesicles that mediate cell communication and typically reflect the phenotype of the cell of origin. MSC-EVs could resemble MSC functions, and are being contemplated as an improved alternative to the MSC-based immunomodulatory therapy. In the present work, we focused on the factors secreted by MSC and aimed to elucidate the putative role of MSC-EVs in the immunomodulation of B cells. EVs and soluble protein-enriched fractions (PF) were isolated from MSC-conditioned medium (CM) using size-exclusion chromatography (SEC) and their capacity to modulate B cell activation, induction of Breg and B cell proliferation was compared to that of the whole MSCs. Co-culture with MSC or unfractionated CM induced naïve and CD24hiCD38hi, IL-10 producing (Breg) phenotypes on B cells while not affecting proliferation. MSC-PF had a comparable effect to MSCs, inducing a naïve phenotype, and even though they did not induce the shift toward a CD24hiCD38hi population, MSC-PF fostered IL-10 production by B cells. Conversely, MSC-EVs failed to promote naïve B cells and to reduce memory B cells. MSC-EVs induced CD24hiCD38hi B cells to a similar extent of that of MSC, but not bona fide Bregs since they did not produce IL-10. Our results show that B cell modulation by MSC is partially mediated by soluble factors other than EVs.

Abstract
The ability to assign cellular origin to low-abundance secreted factors in extracellular vesicles (EVs) would greatly facilitate the analysis of paracrine-mediated signaling. Here, we report a method, named selective isolation of extracellular vesicles (SIEVE), which uses cell type-specific proteome labeling via stochastic orthogonal recoding of translation (SORT) to install bioorthogonal reactive groups into the proteins derived from the cells targeted for labeling. We establish the native purification of intact EVs from a target cell, via a bioorthogonal tetrazine ligation, leading to copurification of the largely unlabeled EV proteome from the same cell. SIEVE enables capture of EV proteins at levels comparable with those obtained by antibody-based methods, which capture all EVs regardless of cellular origin, and at levels 20× higher than direct capture of SORT-labeled proteins. Using proteomic analysis, we analyze nonlabeled cargo proteins of EVs and show that the enhanced sensitivity of SIEVE allows for unbiased and comprehensive analysis of EV proteins from subpopulations of cells as well as for cell-specific EV proteomics in complex coculture systems. SIEVE can be applied with high efficiency in a diverse range of existing model systems for cell–cell communication and has direct applications for cell-of-origin EV analysis and for protein biomarker discovery.

Extracellular vesicles (EVs) are sub-micron-sized membranous spheres secreted by cells. EVs play a functional role as intercellular communicators and are associated with a number of diseases. Research into EVs is an area of growing interest due their many potential uses as therapeutic agents, as diagnostic and theranostic biomarkers, and as regulators of cellular biology. Flow cytometry is a popular method for enumerating and phenotyping EVs, even though the majority of EVs are below the detection sensitivity of most commercially available flow cytometers. Here, we present optimized protocols for EV labeling that increase the signal-to-noise ratio of EVs by removing residual antibody. Protocols for alignment of high-resolution jet-in-air flow cytometers are also provided. Published 2020. U.S. Government. BASIC PROTOCOL 1: Bulk EV staining with CFSE protein binding dye BASIC PROTOCOL 2: Antigen-specific staining of EV markers with fluorochrome-conjugated antibodies BASIC PROTOCOL 3: Astrios EQ instrument setup and sample acquisition BASIC PROTOCOL 4: Counting particles and EVs on Astrios EQ with spike-in reference beads

Extracellular vesicles (EVs) are membranous vesicles containing active proteins, lipids, and different types of genetic material such as miRNAs, mRNAs, and DNAs related to the characteristics of the originating cell. They possess a distinctive capacity to communicate over long distances. EVs have been involved in the modulation of several pathophysiological conditions and, more importantly, stem cell-derived EVs appear as a new promising therapeutic option. In fact, several reports provide convincing evidence of the regenerative potential of EVs released by stem cells and, in particular, mesenchymal stromal cells (MSCs) in different kidney injury models. Described mechanisms involve the reprogramming of injured cells, cell proliferation and angiogenesis, and inhibition of cell apoptosis and inflammation. Besides, the therapeutic use of MSC-EVs in clinical trials is under investigation. This review will focus on MSC-EV applications in preclinical models of acute and chronic renal damage including recent data on their use in kidney transplant conditioning. Moreover, ongoing clinical trials are described. Finally, new strategies to broaden and enhance EV therapeutic efficacy by engineering are discussed. ; This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie Actions, grant agreement No 813839, Innovative Training Network RenalToolBox. This research was founded by the IRMI "Italian Regenerative Medicine Infrastructure" program (Italian Ministry of Health CTN01 00177 88744) and by Regione Piemonte POR FESR 2014/2020—Bando Piattaforma Tecnologica Salute e Benessere—Project "Terapie Avanzate per Processi Fibrotici Cronici (EVER).

Abstract
Extracellular vesicles (EVs) transfer bioactive molecules between cells in a process reminiscent of enveloped viruses. EV cargo delivery is thought to occur by protein-mediated and pH-dependent membrane fusion of the EV and the cellular membrane. However, there is a lack of methods to identify the fusion proteins and resolve their mechanism. We developed and benchmarked an in vitro biophysical assay to investigate EV membrane fusion. The assay was standardized by directly comparing EV and viral fusion with liposomes. We show that EVs and retroviruses fuse with liposomes mimicking the membrane composition of the late endosome in a pH- and protein-dependent manner. Moreover, we directly visualize the stages of membrane fusion using cryo-electron tomography. We find that, unlike most retroviruses, EVs remain fusogenic after acidification and reneutralization. These results provide novel insights into the EV cargo delivery mechanism and an experimental approach to identify the EV fusion machinery.

Tissue regeneration is a hot topic in health sciences, particularly because effective therapies promoting the healing of several cell types are lacking, specifically those of the musculoskeletal system. Mesenchymal Stem/Stromal Cells (MSCs) have been identified as crucial players in bone homeostasis, and are considered a promising therapy for diseases such as osteoarthritis (OA) and Rheumatoid Arthritis (RA). However, some known drawbacks limit their use, particularly ethical issues and immunological rejections. Thus, MSCs byproducts, namely Extracellular Vesicles (EVs), are emerging as potential solutions to overcome some of the issues of the original cells. EVs can be modulated by either cellular preconditioning or vesicle engineering, and thus represent a plastic tool to be implemented in regenerative medicine. Further, the use of biomaterials is important to improve EV delivery and indirectly to modulate their content and secretion. This review aims to connect the dots among MSCs, EVs, and biomaterials, in the context of musculoskeletal diseases. ; This research was funded by European Union's Horizon 2020 Research and Innovation Program under the Marie Skłodowska-Curie grant agreement No 860462-Project PREMUROSA to H.A. and L.R.; by the Italian Ministry of Education, University and Research (MIUR) program "Departments of Excellence 2018–2022", FOHN to A.C. and AGING Projects to A.C.; Fondazione Cariplo 2019-3277 to A.C., European Union's Horizon 2020 Research and Innovation Program under Grant Agreement No.953121—project FLAMIN-GO to L.R. and A.C.; by FISM—Fondazione Italiana Sclerosi Multipla—cod. 2020/PR-Single/021 and financed or co-financed with the '5 per mille' public funding" to G.C.; by European Union's Horizon 2020 research and innovation programme under grant agreement No 952033—project "Twinning to excel materials engineering for medical devices" —ExcellMater to L.R. and A.C.

International audience ; Extracellular vesicles (EV) are emergent therapeutic effectors that have reached clinical trial investigation. To translate EV-based therapeutic to clinic, the challenge is to demonstrate quality, safety, and efficacy, as required for any medicinal product. EV research translation into medicinal products is an exciting and challenging perspective. Recent papers, provide important guidance on regulatory aspects of pharmaceutical development, defining EVs for therapeutic applications and critical considerations for the development of potency tests. In addition, the ISEV Task Force on Regulatory Affairs and Clinical Use of EV-based Therapeutics as well as the Exosomes Committee from the ISCT are expected to contribute in an active way to the development of EV-based medicinal products by providing update on the scientific progress in EVs field, information to patients and expert resource network for regulatory bodies. The contribution of our work group "Extracellular Vesicle translatiOn to clinicaL perspectiVEs - EVOLVE France", created in 2020, can be positioned in complement to all these important initiatives. Based on complementary scientific, technical, and medical expertise, we provide EV-specific recommendations for manufacturing, quality control, analytics, non-clinical development, and clinical trials, according to current European legislation. We especially focus on early phase clinical trials concerning immediate needs in the field. The main contents of the investigational medicinal product dossier, marketing authorization applications, and critical guideline information are outlined for the transition from research to clinical development and ultimate market authorization.

International audience ; Extracellular vesicles (EV) are emergent therapeutic effectors that have reached clinical trial investigation. To translate EV-based therapeutic to clinic, the challenge is to demonstrate quality, safety, and efficacy, as required for any medicinal product. EV research translation into medicinal products is an exciting and challenging perspective. Recent papers, provide important guidance on regulatory aspects of pharmaceutical development, defining EVs for therapeutic applications and critical considerations for the development of potency tests. In addition, the ISEV Task Force on Regulatory Affairs and Clinical Use of EV-based Therapeutics as well as the Exosomes Committee from the ISCT are expected to contribute in an active way to the development of EV-based medicinal products by providing update on the scientific progress in EVs field, information to patients and expert resource network for regulatory bodies. The contribution of our work group "Extracellular Vesicle translatiOn to clinicaL perspectiVEs - EVOLVE France", created in 2020, can be positioned in complement to all these important initiatives. Based on complementary scientific, technical, and medical expertise, we provide EV-specific recommendations for manufacturing, quality control, analytics, non-clinical development, and clinical trials, according to current European legislation. We especially focus on early phase clinical trials concerning immediate needs in the field. The main contents of the investigational medicinal product dossier, marketing authorization applications, and critical guideline information are outlined for the transition from research to clinical development and ultimate market authorization.

International audience ; Extracellular vesicles (EV) are emergent therapeutic effectors that have reached clinical trial investigation. To translate EV-based therapeutic to clinic, the challenge is to demonstrate quality, safety, and efficacy, as required for any medicinal product. EV research translation into medicinal products is an exciting and challenging perspective. Recent papers, provide important guidance on regulatory aspects of pharmaceutical development, defining EVs for therapeutic applications and critical considerations for the development of potency tests. In addition, the ISEV Task Force on Regulatory Affairs and Clinical Use of EV-based Therapeutics as well as the Exosomes Committee from the ISCT are expected to contribute in an active way to the development of EV-based medicinal products by providing update on the scientific progress in EVs field, information to patients and expert resource network for regulatory bodies. The contribution of our work group "Extracellular Vesicle translatiOn to clinicaL perspectiVEs - EVOLVE France", created in 2020, can be positioned in complement to all these important initiatives. Based on complementary scientific, technical, and medical expertise, we provide EV-specific recommendations for manufacturing, quality control, analytics, non-clinical development, and clinical trials, according to current European legislation. We especially focus on early phase clinical trials concerning immediate needs in the field. The main contents of the investigational medicinal product dossier, marketing authorization applications, and critical guideline information are outlined for the transition from research to clinical development and ultimate market authorization.