Biofabrication of Cell-Derived Nanovesicles: A Potential Alternative to Extracellular Vesicles for Regenerative Medicine

Bioderived Nanoparticles for Cardiac Repair

Biobased therapy represents a promising strategy for myocardial repair. However, the limitations of using live cells, including the risk of immunogenicity of allogeneic cells and inconsistent therapeutic efficacy of autologous cells together with low stability, result in an unsatisfactory clinical outcomes. Therefore, cell-free strategies for cardiac tissue repair have been proposed as alternative strategies. Cell-free strategies, primarily based on the paracrine effects of cellular therapy, have demonstrated their potential to inhibit apoptosis, reduce inflammation, and promote on-site cell migration and proliferation, as well as angiogenesis, after an infarction and have been explored preclinically and clinically. Among various cell-free modalities, bioderived nanoparticles, including adeno-associated virus (AAV), extracellular vesicles, cell membrane-coated nanoparticles, and exosome-mimetic nanovesicles, have emerged as promising strategies due to their improved biological function and therapeutic effect. The main focus of this review is the development of existing cellular nanoparticles and their fundamental working mechanisms, as well as the challenges and opportunities. The key processes and requirements for cardiac tissue repair are summarized first. Various cellular nanoparticle modalities are further highlighted, together with their advantages and limitations. Finally, we discuss various delivery approaches that offer potential pathways for researchers and clinicians to translate cell-free strategies for cardiac tissue repair into clinical practice.

Programmable DNA Scaffolds Enable Orthogonal Engineering of Cell Membrane-Based Nanovesicles for Therapeutic Development

Cell membrane-based nanovesicles (CMNVs) play pivotal roles in biomolecular transportation in living organisms and appear as attractive bioinformed nanomaterials for theranostic applications. However, the current surface-engineering technologies are limited in flexibility and orthogonality, making it challenging to simultaneously display multiple different ligands on the CMNV surface in a precisely controlled manner. Here, we developed a DNA scaffold-programmed approach to orthogonally engineer CMNVs with versatile ligands. The designed DNA scaffolds can rapidly anchor onto the CMNV surface, and their unique sequences and hybridized properties enable independent control of the loading of multiple different types of biomolecules on the CMNVs. As a result, the orthogonal engineering of CMNVs with a renal targeted peptide and a therapeutic protein at controlled ratios demonstrated an enhanced renal targeting and repair potential in vivo. This study highlights that a DNA scaffold-programmed platform can provide a potent means for orthogonal and flexible surface engineering of CMNVs for diverse therapeutic purposes.

Endothelial progenitor cell-derived extracellular vesicles: the world of potential prospects for the treatment of cardiovascular diseases

Cardiovascular diseases (CVDs) have emerged as a predominant threat to human health, surpassing the incidence and mortality rates of neoplastic diseases. Extracellular vesicles (EVs) serve as vital mediators in intercellular communication and material exchange. Endothelial progenitor cells (EPCs), recognized as precursors of vascular endothelial cells (ECs), have garnered considerable attention in recent years due to the potential therapeutic value of their derived extracellular vesicles (EPC-EVs) in the context of CVDs. This comprehensive review systematically explores the origins, characteristics, and functions of EPCs, alongside the classification, properties, biogenesis, and extraction techniques of EVs, with particular emphasis on their protective roles in CVDs. Additionally, we delve into the essential bioactive components of EPC-EVs, including microRNAs, long non-coding RNAs, and proteins, analyzing their beneficial effects in promoting angiogenesis, anti-inflammatory and anti-oxidant activities, anti-fibrosis, anti-apoptosis, and myocardial regeneration. Furthermore, this review comprehensively investigates the therapeutic potential of EPC-EVs across various CVDs, encompassing acute myocardial infarction, myocardial ischemia-reperfusion injury, atherosclerosis, non-ischemic cardiomyopathies, and diabetic cardiovascular disease. Lastly, we summarize the potential challenges associated with the clinical application of EPC-EVs and outline future directions, aiming to offer a valuable resource for both theoretical insights and practical applications of EPC-EVs in managing CVDs.

Rhizoma Drynariae-derived nanovesicles reverse osteoporosis by potentiating osteogenic differentiation of human bone marrow mesenchymal stem cells via targeting ERα signaling

Although various anti-osteoporosis drugs are available, the limitations of these therapies, including drug resistance and collateral responses, require the development of novel anti-osteoporosis agents. Rhizoma Drynariae displays a promising anti-osteoporosis effect, while the effective component and mechanism remain unclear. Here, we revealed the therapeutic potential of Rhizoma Drynariae-derived nanovesicles (RDNVs) for postmenopausal osteoporosis and demonstrated that RDNVs potentiated osteogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs) by targeting estrogen receptor-alpha (ERα). RDNVs, a natural product isolated from fresh Rhizoma Drynariae root juice by differential ultracentrifugation, exhibited potent bone tissue-targeting activity and anti-osteoporosis efficacy in an ovariectomized mouse model. RDNVs, effectively internalized by hBMSCs, enhanced proliferation and ERα expression levels of hBMSC, and promoted osteogenic differentiation and bone formation. Mechanistically, via the ERα signaling pathway, RDNVs facilitated mRNA and protein expression of bone morphogenetic protein 2 and runt-related transcription factor 2 in hBMSCs, which are involved in regulating osteogenic differentiation. Further analysis revealed that naringin, existing in RDNVs, was the active component targeting ERα in the osteogenic effect. Taken together, our study identified that naringin in RDNVs displays exciting bone tissue-targeting activity to reverse osteoporosis by promoting hBMSCs proliferation and osteogenic differentiation through estrogen-like effects.

The Landscape of Biomimetic Nanovesicles in Brain Diseases

Brain diseases, such as brain tumors, neurodegenerative diseases, cerebrovascular diseases, and brain injuries, are caused by various pathophysiological changes, which pose a serious health threat. Brain disorders are often difficult to treat due to the presence of the blood-brain barrier (BBB). Biomimetic nanovesicles (BNVs), including endogenous extracellular vesicles (EVs) derived from various cells and artificial nanovesicles, possess the ability to penetrate the BBB and thus can be utilized for drug delivery to the brain. BNVs, especially endogenous EVs, are widely distributed in body fluids and usually carry various disease-related signal molecules such as proteins, RNA, and DNA, and may also be analyzed to understand the etiology and pathogenesis of brain diseases. This review covers the exhaustive classification and characterization of BNVs and pathophysiological roles involved in various brain diseases, and emphatically focuses on nanotechnology-integrated BNVs for brain disease theranostics, including various diagnosis strategies and precise therapeutic regulations (e.g., immunity regulation, disordered protein clearance, anti-neuroinflammation, neuroregeneration, angiogenesis, and the gut-brain axis regulation). The remaining challenges and future perspectives regarding the nanotechnology-integrated BNVs for the diagnosis and treatment of brain diseases are also discussed and outlined.

Exosome-based delivery strategies for tumor therapy: an update on modification, loading, and clinical application

Malignancy is a major public health problem and among the leading lethal diseases worldwide. Although the current tumor treatment methods have therapeutic effect to a certain extent, they still have some shortcomings such as poor water solubility, short half-life, local and systemic toxicity. Therefore, how to deliver therapeutic agent so as to realize safe and effective anti-tumor therapy become a problem urgently to be solved in this field. As a medium of information exchange and material transport between cells, exosomes are considered to be a promising drug delivery carrier due to their nano-size, good biocompatibility, natural targeting, and easy modification. In this review, we summarize recent advances in the isolation, identification, drug loading, and modification of exosomes as drug carriers for tumor therapy alongside their application in tumor therapy. Basic knowledge of exosomes, such as their biogenesis, sources, and characterization methods, is also introduced herein. In addition, challenges related to the use of exosomes as drug delivery vehicles are discussed, along with future trends. This review provides a scientific basis for the application of exosome delivery systems in oncological therapy.

Formation and Investigation of Cell-Derived Nanovesicles as Potential Therapeutics against Chronic Liver Disease

A new therapeutic approach using cell-derived nanovesicles (cdNVs) is offered here to overcome the lack of effective treatments for liver fibrosis, a reversible chronic liver disease. To achieve this goal the formation and purification of cdNVs from untreated, quiescent-like, or activated LX-2 cells, an immortalized human hepatic stellate cell (HSC) line with key features of transdifferentiated HSCs are established. Analysis of the genotype and phenotype of naïve and transdifferentiated LX-2 cells activated through transforming growth factor beta 1, following treatment with cdNVs, reveals a concentration-dependent fibrosis regression. The beneficial fibrosis-resolving effects of cdNVs are linked to their biomolecular corona. Liposomes generated using lipids extracted from cdNVs exhibit a reduced antifibrotic response in perpetuated LX-2 cells and show a reduced cellular uptake. However, incubation with soluble factors collected during purification results in a new corona, thereby restoring fibrosis regression activity. Overall, cdNVs display encouraging therapeutic properties, making them a promising candidate for the development of liver fibrosis resolving therapeutics.

Strategies for targeted gene delivery using lipid nanoparticles and cell-derived nanovesicles

Gene therapy is a promising approach for the treatment of many diseases. However, the effective delivery of the cargo without degradation in vivo is one of the major hurdles. With the advent of lipid nanoparticles (LNPs) and cell-derived nanovesicles (CDNs), gene delivery holds a very promising future. The targeting of these nanosystems is a prerequisite for effective transfection with minimal side-effects. In this review, we highlight the emerging strategies utilized for the effective targeting of LNPs and CDNs, and we summarize the preparation methodologies for LNPs and CDNs. We have also highlighted the non-ligand targeting of LNPs toward certain organs based on their composition. It is highly expected that continuing the developments in the targeting approaches of LNPs and CDNs for the delivery system will further promote them in clinical translation.

Tailoring the Inherent Properties of Biobased Nanoparticles for Nanomedicine

Biobased nanoparticles are at the leading edge of the rapidly developing field of nanomedicine and biotherapeutics. Their unique size, shape, and biophysical properties make them attractive tools for biomedical research, including vaccination, targeted drug delivery, and immune therapy. These nanoparticles are engineered to present native cell receptors and proteins on their surfaces, providing a biomimicking camouflage for therapeutic cargo to evade rapid degradation, immune rejection, inflammation, and clearance. Despite showing promising clinical relevance, commercial implementation of these biobased nanoparticles is yet to be fully realized. In this perspective, we discuss advanced biobased nanoparticle designs used in medical applications, such as cell membrane nanoparticles, exosomes, and synthetic lipid-derived nanoparticles, and highlight their benefits and potential challenges. Moreover, we critically assess the future of preparing such particles using artificial intelligence and machine learning. These advanced computational tools will be able to predict the functional composition and behavior of the proteins and cell receptors present on the nanoparticle surfaces. With more advancement in designing new biobased nanoparticles, this field of research could play a key role in dictating the future rational design of drug transporters, thereby ultimately improving overall therapeutic outcomes.

Technological aspects of manufacturing and analytical control of biological nanoparticles

Extracellular vesicles (EVs) are cell-derived biological nanoparticles that gained great interest for drug delivery. EVs have numerous advantages compared to synthetic nanoparticles, such as ideal biocompatibility, safety, ability to cross biological barriers and surface modification via genetic or chemical methods. On the other hand, the translation and the study of these carriers resulted difficult, mostly because of significant issues in up-scaling, synthesis and impractical methods of quality control. However, current manufacturing advances enable EV packaging with any therapeutic cargo, including DNA, RNA (for RNA vaccines and RNA therapeutics), proteins, peptides, RNA-protein complexes (including gene-editing complexes) and small molecules drugs. To date, an array of new and upgraded technologies have been introduced, substantially improving EV production, isolation, characterization and standardization. The used-to-be "gold standards" of EV manufacturing are now outdated, and the state-of-art requires extensive revision. This review re-evaluates the pipeline for EV industrial production and provides a critical overview of the modern technologies required for their synthesis and characterization.

Methods for the identification and characterization of extracellular vesicles in cardiovascular studies: from exosomes to microvesicles

Extracellular vesicles (EVs) are nanosized vesicles with a lipid bilayer that are released from cells of the cardiovascular system, and are considered important mediators of intercellular and extracellular communications. Two types of EVs of particular interest are exosomes and microvesicles, which have been identified in all tissue and body fluids and carry a variety of molecules including RNAs, proteins, and lipids. EVs have potential for use in the diagnosis and prognosis of cardiovascular diseases and as new therapeutic agents, particularly in the setting of myocardial infarction and heart failure. Despite their promise, technical challenges related to their small size make it challenging to accurately identify and characterize them, and to study EV-mediated processes. Here, we aim to provide the reader with an overview of the techniques and technologies available for the separation and characterization of EVs from different sources. Methods for determining the protein, RNA, and lipid content of EVs are discussed. The aim of this document is to provide guidance on critical methodological issues and highlight key points for consideration for the investigation of EVs in cardiovascular studies.

Comparison of extruded cell nanovesicles and exosomes in their molecular cargos and regenerative potentials

Extracellular vesicles (EVs) generated from mesenchymal stem cells (MSCs) play an essential role in modulating cell-cell communication and tissue regeneration. The clinical translation of EVs is constrained by the poor yield of EVs. Extrusion has recently become an effective technique for producing a large scale of nanovesicles (NVs). In this study, we systematically compared MSC NVs (from extrusion) and EVs (from natural secretion). Proteomics and RNA sequencing data revealed that NVs resemble MSCs more closely than EVs. Additionally, microRNAs in NVs are related to cardiac repair, fibrosis repression, and angiogenesis. Lastly, intravenous delivery of MSC NVs improved heart repair and cardiac function in a mouse model of myocardial infarction.

Electronic Supplementary Material

Supplementary material (Figs. S1-S4) is available in the online version of this article at 10.1007/s12274-023-5374-3.

Current challenges and future directions for engineering extracellular vesicles for heart, lung, blood and sleep diseases

Extracellular vesicles (EVs) carry diverse bioactive components including nucleic acids, proteins, lipids and metabolites that play versatile roles in intercellular and interorgan communication. The capability to modulate their stability, tissue-specific targeting and cargo render EVs as promising nanotherapeutics for treating heart, lung, blood and sleep (HLBS) diseases. However, current limitations in large-scale manufacturing of therapeutic-grade EVs, and knowledge gaps in EV biogenesis and heterogeneity pose significant challenges in their clinical application as diagnostics or therapeutics for HLBS diseases. To address these challenges, a strategic workshop with multidisciplinary experts in EV biology and U.S. Food and Drug Administration (USFDA) officials was convened by the National Heart, Lung and Blood Institute. The presentations and discussions were focused on summarizing the current state of science and technology for engineering therapeutic EVs for HLBS diseases, identifying critical knowledge gaps and regulatory challenges and suggesting potential solutions to promulgate translation of therapeutic EVs to the clinic. Benchmarks to meet the critical quality attributes set by the USFDA for other cell-based therapeutics were discussed. Development of novel strategies and approaches for scaling-up EV production and the quality control/quality analysis (QC/QA) of EV-based therapeutics were recognized as the necessary milestones for future investigations.

Effects of mesenchymal stem cell-derived nanovesicles in experimental allergic airway inflammation

BACKGROUND

Allergic asthma is associated with airflow obstruction and hyper-responsiveness that arises from airway inflammation and remodeling. Cell therapy with mesenchymal stem cells (MSC) has been shown to attenuate inflammation in asthma models, and similar effects have recently been observed using extracellular vesicles (EV) obtained from these cells. Biologically functional vesicles can also be artificially generated from MSC by extruding cells through membranes to produce EV-mimetic nanovesicles (NV). In this study, we aimed to determine the effects of different MSC-derived vesicles in a murine model of allergic airway inflammation.

METHODS

EV were obtained through sequential centrifugation of serum-free media conditioned by human bone marrow MSC for 24 h. NV were produced through serial extrusion of the whole cells through filters. Both types of vesicles underwent density gradient purification and were quantified through nanoparticle tracking analysis. C57BL/6 mice were sensitized to ovalbumin (OVA, 8 µg), and then randomly divided into the OVA group (intranasally exposed to 100 µg OVA for 5 days) and control group (exposed to PBS). The mice were then further divided into groups that received 2 × 10⁹ EV or NV (intranasally or intraperitoneally) or PBS immediately following the first OVA exposure.

RESULTS

Administration of EV and NV reduced cellularity and eosinophilia in bronchoalveolar lavage (BAL) fluid in OVA-sensitized and OVA-exposed mice. In addition, NV treatment resulted in decreased numbers of inflammatory cells within the lung tissue, and this was associated with lower levels of Eotaxin-2 in both BAL fluid and lung tissue. Furthermore, both intranasal and systemic administration of NV were effective in reducing inflammatory cells; however, systemic delivery resulted in a greater reduction of eosinophilia in the lung tissue.

CONCLUSIONS

Taken together, our results indicate that MSC-derived NV significantly reduce OVA-induced allergic airway inflammation to a level comparable to EV. Thus, cell-derived NV may be a novel EV-mimetic therapeutic candidate for treating allergic diseases such as asthma.

Meet changes with constancy: Defence, antagonism, recovery, and immunity roles of extracellular vesicles in confronting SARS-CoV-2

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has wrought havoc on the world economy and people's daily lives. The inability to comprehensively control COVID-19 is due to the difficulty of early and timely diagnosis, the lack of effective therapeutic drugs, and the limited effectiveness of vaccines. The body contains billions of extracellular vesicles (EVs), which have shown remarkable potential in disease diagnosis, drug development, and vaccine carriers. Recently, increasing evidence has indicated that EVs may participate or assist the body in defence, antagonism, recovery and acquired immunity against SARS-CoV-2. On the one hand, intercepting and decrypting the general intelligence carried in circulating EVs from COVID-19 patients will provide an important hint for diagnosis and treatment; on the other hand, engineered EVs modified by gene editing in the laboratory will amplify the effectiveness of inhibiting infection, replication and destruction of ever-mutating SARS-CoV-2, facilitating tissue repair and making a better vaccine. To comprehensively understand the interaction between EVs and SARS-CoV-2, providing new insights to overcome some difficulties in the diagnosis, prevention and treatment of COVID-19, we conducted a rounded review in this area. We also explain numerous critical challenges that these tactics face before they enter the clinic, and this work will provide previous 'meet change with constancy' lessons for responding to future similar public health disasters. Extracellular vesicles (EVs) provide a 'meet changes with constancy' strategy to combat SARS-CoV-2 that spans defence, antagonism, recovery, and acquired immunity. Targets for COVID-19 diagnosis, therapy, and prevention of progression may be found by capture of the message decoding in circulating EVs. Engineered and biomimetic EVs can boost effects of the natural EVs, especially anti-SARS-CoV-2, targeted repair of damaged tissue, and improvement of vaccine efficacy.

Extruded small extracellular vesicles: splinters of circulating tumour cells may promote cancer metastasis?

We speculate ruptured circulating tumour cells (CTC) in capillaries could release a large number of small extracellular vesicle-like vesicles, namely mechanically extruded sEV (sEVme), which can encapsulate chromosomal DNA fragments. These sEVme have similar physicochemical properties compared to small extracellular vesicles spontaneously secreted by living cells (sEVss), and thus sEVme and sEVss cannot be effectively distinguished based on their size or membrane protein markers. Meanwhile, these sEVme derived from CTC inherit oncogenic payloads, deliver cargo through the bloodstream to recipient cells, and thus may promote cancer metastasis. The validation of this speculation could facilitate our understanding of EV biogenesis and cancer pathology. The potential finding will also provide a theoretical foundation for burgeoning liquid biopsy using DNA fragments derived from harvested sEV.

A lipid nanoparticle platform for mRNA delivery through repurposing of cationic amphiphilic drugs

Since the recent clinical approval of siRNA-based drugs and COVID-19 mRNA vaccines, the potential of RNA therapeutics for patient healthcare has become widely accepted. Lipid nanoparticles (LNPs) are currently the most advanced nanocarriers for RNA packaging and delivery. Nevertheless, the intracellular delivery efficiency of state-of-the-art LNPs remains relatively low and safety and immunogenicity concerns with synthetic lipid components persist, altogether rationalizing the exploration of alternative LNP compositions. In addition, there is an interest in exploiting LNP technology for simultaneous encapsulation of small molecule drugs and RNA in a single nanocarrier. Here, we describe how well-known tricyclic cationic amphiphilic drugs (CADs) can be repurposed as both structural and functional components of lipid-based NPs for mRNA formulation, further referred to as CADosomes. We demonstrate that selected CADs, such as tricyclic antidepressants and antihistamines, self-assemble with the widely-used helper lipid DOPE to form cationic lipid vesicles for subsequent mRNA complexation and delivery, without the need for prior lipophilic derivatization. Selected CADosomes enabled efficient mRNA delivery in various in vitro cell models, including easy-to-transfect cancer cells (e.g. human cervical carcinoma HeLa cell line) as well as hard-to-transfect primary cells (e.g. primary bovine corneal epithelial cells), outperforming commercially available cationic liposomes and state-of-the-art LNPs. In addition, using the antidepressant nortriptyline as a model compound, we show that CADs can maintain their pharmacological activity upon CADosome incorporation. Furthermore, in vivo proof-of-concept was obtained, demonstrating CADosome-mediated mRNA delivery in the corneal epithelial cells of rabbit eyes, which could pave the way for future applications in ophthalmology. Based on our results, the co-formulation of CADs, helper lipids and mRNA into lipid-based nanocarriers is proposed as a versatile and straightforward approach for the rational development of drug combination therapies.

Recent advancement of bioinspired nanomaterials and their applications: A review

With the advancement in the field of nanotechnology, different approaches for the synthesis of nanomaterials have been formulated, among which the bioinspired or biomimetic nanoplatforms have been utilized for different biomedical applications. In this context, bioinspired or biomimetic nanoparticles (NPs) have been synthesized in which the inspiration for synthesis is taken from nature or its components. Innovations in bioengineering tools and bio-conjugation chemistry have enabled scientists to develop novel types of such nanoplatforms. They have several advantages over normal synthesis protocols. In this review, we 1) summarized nanomaterial types and their advancements in bioinspired nanotechnology therapies; 2) discussed the major types, novel preparation methods, and synthesis progress of NPs in current biomedical fields; 3) gave a brief account of the need for synthesizing NPs via a bioinspired route rather than their common route; 4) highlighted the updated information on the biomimetic synthesis of different types of NPs; and 5) provided future perspectives in the synthesis of novel NPs for their potential applications in biomedical sciences.

Manufacturing Therapeutic Exosomes: from Bench to Industry

Process of manufacturing therapeutics exosome development for commercialization. The development of exosome treatment starts at the bench, and in order to be commercialized, it goes through the manufacturing, characterization, and formulation stages, production under Good Manufacturing Practice (GMP) conditions for clinical use, and close consultation with regulatory authorities. Exosome, a type of nanoparticles also known as small extracellular vesicles are gaining attention as novel therapeutics for various diseases because of their ability to deliver genetic or bioactive molecules to recipient cells. Although many pharmaceutical companies are gradually developing exosome therapeutics, numerous hurdles remain regarding manufacture of clinical-grade exosomes for therapeutic use. In this mini-review, we will discuss the manufacturing challenges of therapeutic exosomes, including cell line development, upstream cell culture, and downstream purification process. In addition, developing proper formulations for exosome storage and, establishing good manufacturing practice facility for producing therapeutic exosomes remains as challenges for developing clinicalgrade exosomes. However, owing to the lack of consensus regarding the guidelines for manufacturing therapeutic exosomes, close communication between regulators and companies is required for the successful development of exosome therapeutics. This review shares the challenges and perspectives regarding the manufacture and quality control of clinical grade exosomes.

Exosome Mimetics-Loaded Hydrogel Accelerates Wound Repair by Transferring Functional Mitochondrial Proteins

Loading human umbilical mesenchymal stem cell (hUMSC) derived exosomes onto hydrogel scaffolds is a strategy for rapid wound healing. The clinical application of exosomes is hindered by low production, and exosome mimetics could be substituted for exosomes. Here, the therapeutic effects of exosome-loaded hydrogels and exosome mimetic-loaded hydrogels on wounds are evaluated. Our results revealed that exosome mimetic-loaded hydrogels promote wound healing more efficiently than exosome-loaded hydrogels. Exosome mimetics can promote the proliferation and migration of dermal fibroblasts (hDF-a) cells in vitro. To investigate how exosome mimetics play a role, proteomics analysis was applied, and the obtained results suggested that exosome mimetics significantly enrich mitochondrial-derived oxidative phosphorylation-related proteins in comparison to exosomes. Overall, our work envisages the emerging potential of exosome mimetics, which take the advantage of exosomes and can be promising candidates for exosomes. It also suggests that hUMSC-derived exosome mimetic-loaded hydrogels have remarkable prospects for clinical application.

Elucidating Design Principles for Engineering Cell-Derived Vesicles to Inhibit SARS-CoV-2 Infection

The ability of pathogens to develop drug resistance is a global health challenge. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) presents an urgent need wherein several variants of concern resist neutralization by monoclonal antibody (mAb) therapies and vaccine-induced sera. Decoy nanoparticles-cell-mimicking particles that bind and inhibit virions-are an emerging class of therapeutics that may overcome such drug resistance challenges. To date, quantitative understanding as to how design features impact performance of these therapeutics is lacking. To address this gap, this study presents a systematic, comparative evaluation of various biologically derived nanoscale vesicles, which may be particularly well suited to sustained or repeated administration in the clinic due to low toxicity, and investigates their potential to inhibit multiple classes of model SARS-CoV-2 virions. A key finding is that such particles exhibit potent antiviral efficacy across multiple manufacturing methods, vesicle subclasses, and virus-decoy binding affinities. In addition, these cell-mimicking vesicles effectively inhibit model SARS-CoV-2 variants that evade mAbs and recombinant protein-based decoy inhibitors. This study provides a foundation of knowledge that may guide the design of decoy nanoparticle inhibitors for SARS-CoV-2 and other viral infections.

Extracellular Vesicles in Musculoskeletal Regeneration: Modulating the Therapy of the Future

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.

Elucidating design principles for engineering cell-derived vesicles to inhibit SARS-CoV-2 infection

The ability of pathogens to develop drug resistance is a global health challenge. The SARS-CoV-2 virus presents an urgent need wherein several variants of concern resist neutralization by monoclonal antibody therapies and vaccine-induced sera. Decoy nanoparticles-cell-mimicking particles that bind and inhibit virions-are an emerging class of therapeutics that may overcome such drug resistance challenges. To date, we lack quantitative understanding as to how design features impact performance of these therapeutics. To address this gap, here we perform a systematic, comparative evaluation of various biologically-derived nanoscale vesicles, which may be particularly well-suited to sustained or repeated administration in the clinic due to low toxicity, and investigate their potential to inhibit multiple classes of model SARS-CoV-2 virions. A key finding is that such particles exhibit potent antiviral efficacy across multiple manufacturing methods, vesicle subclasses, and virus-decoy binding affinities. In addition, these cell-mimicking vesicles effectively inhibit model SARS-CoV-2 variants that evade monoclonal antibodies and recombinant protein-based decoy inhibitors. This study provides a foundation of knowledge that may guide the design of decoy nanoparticle inhibitors for SARS-CoV-2 and other viral infections.

Extruded Mesenchymal Stem Cell Nanovesicles Are Equally Potent to Natural Extracellular Vesicles in Cardiac Repair

Mesenchymal stem cells (MSCs) repair injured tissues mainly through their paracrine actions. One of the important paracrine components of MSC secretomes is the extracellular vesicle (EV). The therapeutic potential of MSC-EVs has been established in various cardiac injury preclinical models. However, the large-scale production of EVs remains a challenge. We sought to develop a scale-up friendly method to generate a large number of therapeutic nanovesicles from MSCs by extrusion. Those extruded nanovesicles (NVs) are miniature versions of MSCs in terms of surface marker expression. The yield of NVs is 20-fold more than that of EVs. In vitro, cell-based assays demonstrated the myocardial protective effects and therapeutic potential of NVs. Intramyocardial delivery of NVs in the injured heart after ischemia-reperfusion led to a reduction in scar sizes and preservation of cardiac functions. Such therapeutic benefits are similar to those injected with natural EVs from the same MSC parental cells. In addition, NV therapy promoted angiogenesis and proliferation of cardiomyocytes in the post-injury heart. In summary, extrusion is a highly efficient method to generate a large quantity of therapeutic NVs that can potentially replace extracellular vesicles in regenerative medicine applications.

Thinking Quantitatively of RNA-Based Information Transfer via Extracellular Vesicles: Lessons to Learn for the Design of RNA-Loaded EVs

Extracellular vesicles (EVs) are 50–1000 nm vesicles secreted by virtually any cell type in the body. They are expected to transfer information from one cell or tissue to another in a short- or long-distance way. RNA-based transfer of information via EVs at long distances is an interesting well-worn hypothesis which is ~15 years old. We review from a quantitative point of view the different facets of this hypothesis, ranging from natural RNA loading in EVs, EV pharmacokinetic modeling, EV targeting, endosomal escape and RNA delivery efficiency. Despite the unique intracellular delivery properties endowed by EVs, we show that the transfer of RNA naturally present in EVs might be limited in a physiological context and discuss the lessons we can learn from this example to design efficient RNA-loaded engineered EVs for biotherapies. We also discuss other potential EV mediated information transfer mechanisms, among which are ligand–receptor mechanisms.

Nano-structured myelin: new nanovesicles for targeted delivery to white matter and microglia, from brain-to-brain

Neurodegenerative diseases affect millions of people worldwide and the presence of various physiological barriers limits the accessibility to the brain and reduces the efficacy of various therapies. Moreover, new carriers having targeting properties to specific brain regions and cells are needed in order to improve therapies for the brain disorder treatment. In this study, for the first time, Myelin nanoVesicles (hereafter defined MyVes) from brain-extracted myelin were produced. The MyVes have an average diameter of 100–150 ​nm, negative zeta potential, spheroidal morphology, and contain lipids and the key proteins of the myelin sheath. Furthermore, they exhibit good cytocompatibility. The MyVes were able to target the white matter and interact mainly with the microglia cells. The preliminary results here presented allow us to suppose the employment of MyVes as potential carrier to target the white matter and microglia in order to counteract white matter microglia-related diseases.

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Bio-fabrication of brain tissue derived nanovesicles: myelin nanovesicles.

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Myelin nanovesicles contain the main proteins of the myelin sheath (myelin basic protein and myelin proteolipid protein).

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Myelin nanovesicles can lade a drug/molecule and cross a blood–brain barrier model.

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Myelin nanovesicles target white matter and microglia cells.

A New Role for Extracellular Vesicles in Cardiac Tissue Engineering and Regenerative Medicine

Cardiovascular diseases are the leading cause of death worldwide. Discovering new therapies to treat heart disease requires improved understanding of cardiac physiology at a cellular level. Extracellular vesicles (EVs) are plasma membrane-bound nano- and microparticles secreted by cells and known to play key roles in intercellular communication, often through transfer of biomolecular cargo. Advances in EV research have established techniques for EV isolation from tissue culture media or biofluids, as well as standards for quantitation and biomolecular characterization. EVs released by cardiac cells are known to be involved in regulating cardiac physiology as well as in the progression of myocardial diseases. Due to difficulty accessing the heart in vivo, advanced in vitro cardiac 'tissues-on-a-chip' have become a recent focus for studying EVs in the heart. These physiologically relevant models are producing new insight into the role of EVs in cardiac physiology and disease while providing a useful platform for screening novel EV-based therapeutics for cardiac tissue regeneration post-injury. Numerous hurdles have stalled the clinical translation of EV therapeutics for heart patients, but tissue-on-a-chip models are playing an important role in bridging the translational gap, improving mechanistic understanding of EV signalling in cardiac physiology, disease, and repair.

Dually targeted bioinspired nanovesicle delays advanced prostate cancer tumour growth in vivo

Prostate cancer (PC) is second-leading cancer in men, with limited treatment options available for men with advanced and metastatic PC. Prostate-specific antigen (PSA) and prostate-specific membrane antigen (PSMA) have been exploited as therapeutic targets in PC due to their upregulation in the advanced stages of the disease. To date, several PSA- and PSMA-activatable prodrugs have been developed to reduce the systemic toxicity of existing chemotherapeutics. Bioinspired nanovesicles have been exploited in drug delivery, offering prolonged drug blood circulation and higher tumour accumulation. For the first time, this study describes the engineering of dually targeted PSA/PSMA nanovesicles for advanced PC. PSMA-targeted bioinspired hybrids were prepared by hydrating a lipid film with anti-PSMA-U937 cell membranes and DOX-PSA prodrug, followed by extrusion. The bioinspired hybrids were characterised using dynamic light scattering, transmission electron microscopy, Dot blot, flow cytometry and Western blot. Cellular binding and toxicity studies in PC cancer cell lines were carried out using flow cytometry, confocal microscopy, and resazurin assay. Finally, tumour targeting and therapeutic efficacy studies were performed in solid and metastatic C4-2B-tumor-bearing mice. Interestingly, our PSMA-targeted hybrids demonstrated high cell uptake in PSMA-expressing cells with significant accumulation in solid and metastatic C4-2B tumour tissues following intravenous administration. More promisingly, our dually targeted PSA/PSMA hybrid significantly slowed down the C4-2B tumour growth in vivo, compared to free DOX-PSA and non-targeted PSA-hybrid. Our PSA/PSMA bioinspired hybrid could offer a highly selective treatment for advanced PC with lower side effects. STATEMENT OF SIGNIFICANCE: This study investigates a new approach to treat prostate cancer using dually targeted bioinspired nanovesicle . Our bioinspired vesicles are made mainly of a human blood cell membrane with a ligand recognising a specific marker (PSMA) on the surface of the prostate cancer cells. The present work describes the successful loading of a doxorubicin prodrug linked to a PSA- activatable peptide into these targeted bioinspired nanovesicle , where the active PSA enzyme presents in these cells converts the drug to its active form. Our dually targeted PSA/PSMA hybrid vesicles has successfully improved site-specific prodrug delivery to tackle advanced prostate cancer, offering a novel and effective prostate cancer treatment.

Multiple Sclerosis: Focus on Extracellular and Artificial Vesicles, Nanoparticles as Potential Therapeutic Approaches

Multiple sclerosis (MS) is an autoimmune disease of the Central Nervous System, characterized by an inflammatory process leading to the destruction of myelin with neuronal death and neurodegeneration. In MS, lymphocytes cross the blood-brain barrier, creating inflammatory demyelinated plaques located primarily in the white matter. MS potential treatments involve various mechanisms of action on immune cells, immunosuppression, inhibition of the passage through the blood-brain barrier, and immunotolerance. Bio-nanotechnology represents a promising approach to improve the treatment of autoimmune diseases by its ability to affect the immune responses. The use of nanotechnology has been actively investigated for the development of new MS therapies. In this review, we summarize the results of the studies on natural and artificial vesicles and nanoparticles, and take a look to the future clinical perspectives for their application in the MS therapy.

Lyophilization Preserves the Intrinsic Cardioprotective Activity of Bioinspired Cell-Derived Nanovesicles

Recently, bioinspired cell-derived nanovesicles (CDNs) have gained much interest in the field of nanomedicine due to the preservation of biomolecular structure characteristics derived from their parent cells, which impart CDNs with unique properties in terms of binding and uptake by target cells and intrinsic biological activities. Although the production of CDNs can be easily and reproducibly achieved with any kind of cell culture, application of CDNs for therapeutic purposes has been greatly hampered by their physical and chemical instability during long-term storage in aqueous dispersion. In the present study, we conceived a lyophilization approach that would preserve critical characteristics regarding stability (vesicles' size and protein content), structural integrity, and biological activity of CDNs for enabling long-term storage in freeze-dried form. Compared to the lyoprotectant sucrose, trehalose-lyoprotected CDNs showed significantly higher glass transition temperature and lower residual moisture content. As assessed by ATR-FTIR and far-UV circular dichroism, lyophilization in the presence of the lyoprotectant effectively maintained the secondary structure of cellular proteins. After reconstitution, lyoprotected CDNs were efficiently associated with HeLa cells, CT26 cells, and bone marrow-derived macrophages at a rate comparable to the freshly prepared CDNs. In vivo, both lyoprotected and freshly prepared CDNs, for the first time ever reported, targeted the injured heart, and exerted intrinsic cardioprotective effects within 24 h, attributable to the antioxidant capacity of CDNs in a myocardial ischemia/reperfusion injury animal model. Taken together, these results pave the way for further development of CDNs as cell-based therapeutics stabilized by lyophilization that enabled long-term storage while preserving their activity.

Hijacking Endocytosis and Autophagy in Extracellular Vesicle Communication: Where the Inside Meets the Outside

Extracellular vesicles, phospholipid bilayer-membrane vesicles of cellular origin, are emerging as nanocarriers of biological information between cells. Extracellular vesicles transport virtually all biologically active macromolecules (e.g., nucleotides, lipids, and proteins), thus eliciting phenotypic changes in recipient cells. However, we only partially understand the cellular mechanisms driving the encounter of a soluble ligand transported in the lumen of extracellular vesicles with its cytosolic receptor: a step required to evoke a biologically relevant response. In this context, we review herein current evidence supporting the role of two well-described cellular transport pathways: the endocytic pathway as the main entry route for extracellular vesicles and the autophagic pathway driving lysosomal degradation of cytosolic proteins. The interplay between these pathways may result in the target engagement between an extracellular vesicle cargo protein and its cytosolic target within the acidic compartments of the cell. This mechanism of cell-to-cell communication may well own possible implications in the pathogenesis of neurodegenerative disorders.

Modern isolation and separation techniques for extracellular vesicles

Extracellular vesicles (EVs) are heterogenous membrane-bound vesicles released from various origins. EVs play a crucial role in cellular communication and mediate several physiological and pathological processes, highlighting their potential therapeutic and diagnostic applications. Due to the rapid increase in interests and needs to elucidate EV properties and functions, numerous isolation and separation approaches for EVs have been developed to overcome limitations of conventional techniques, such as ultracentrifugation. This review focuses on recently emerging and modern EV isolation and separation techniques, including size-, charge-, and affinity-based techniques while excluding ultracentrifugation and precipitation-based techniques due to their multiple limitations. The advantages and drawbacks of each technique are discussed together with insights into their applications. Emerging approaches all share similar features in terms of being time-effective, easy-to-operate, and capable of providing EVs with suitable and desirable purity and integrity for applications of interest. Combination and hyphenation of techniques have been used for EV isolation and separation to yield EVs with the best quality. The most recent development using an automated on-line system including selective affinity-based trapping unit and asymmetrical flow field-flow fractionation allows reliable isolation and fractionation of EV subpopulations from human plasma.

Myocardial infarction affects Cx43 content of extracellular vesicles secreted by cardiomyocytes

Ischemic heart disease has been associated with an impairment on intercellular communication mediated by both gap junctions and extracellular vesicles. We have previously shown that connexin 43 (Cx43), the main ventricular gap junction protein, assembles into channels at the extracellular vesicle surface, mediating the release of vesicle content into target cells. Here, using a comprehensive strategy that included cell-based approaches, animal models and human patients, we demonstrate that myocardial ischemia impairs the secretion of Cx43 into circulating, intracardiac and cardiomyocyte-derived vesicles. In addition, we show that ubiquitin signals Cx43 release in basal conditions but appears to be dispensable during ischemia, suggesting an interplay between ischemia-induced Cx43 degradation and secretion. Overall, this study constitutes a step forward for the characterization of the signals and molecular players underlying vesicle protein sorting, with strong implications on long-range intercellular communication, paving the way towards the development of innovative diagnostic and therapeutic strategies for cardiovascular disorders.

Repairing the heart: State-of the art delivery strategies for biological therapeutics

Myocardial infarction (MI) is one of the leading causes of mortality worldwide. It is caused by an acute imbalance between oxygen supply and demand in the myocardium, usually caused by an obstruction in the coronary arteries. The conventional therapy is based on the application of (a combination of) anti-thrombotics, reperfusion strategies to open the occluded artery, stents and bypass surgery. However, numerous patients cannot fully recover after these interventions. In this context, new therapeutic methods are explored. Three decades ago, the first biologicals were tested to improve cardiac regeneration. Angiogenic proteins gained popularity as potential therapeutics. This is not straightforward as proteins are delicate molecules that in order to have a reasonably long time of activity need to be stabilized and released in a controlled fashion requiring advanced delivery systems. To ensure long-term expression, DNA vectors-encoding for therapeutic proteins have been developed. Here, the nuclear membrane proved to be a formidable barrier for efficient expression. Moreover, the development of delivery systems that can ensure entry in the target cell, and also correct intracellular trafficking towards the nucleus are essential. The recent introduction of mRNA as a therapeutic entity has provided an attractive intermediate: prolonged but transient expression from a cytoplasmic site of action. However, protection of the sensitive mRNA and correct delivery within the cell remains a challenge. This review focuses on the application of synthetic delivery systems that target the myocardium to stimulate cardiac repair using proteins, DNA or RNA.

Extracellular vesicles in cardiovascular disease

Cardiovascular disease remains the leading cause of morbidity and mortality globally. Extracellular vesicles (EVs), a group of heterogeneous nanosized cell-derived vesicles, have attracted great interest as liquid biopsy material for biomarker discovery in a variety of diseases including cardiovascular disease. Because EVs inherit bioactive components from parent cells and are able to transfer their contents to recipient cells, EVs hold great promise as potential cell-free therapeutics and drug delivery systems. However, the development of EV-based diagnostics, therapeutics or drug delivery systems has been challenging due to the heterogenicity of EVs in biogenesis, size and cellular origin, the lack of standardized isolation and purification methods as well as the low production yield. In this review, we will provide an overview of the recent advances in EV-based biomarker discovery, highlight the potential usefulness of EVs and EV mimetics for therapeutic treatment and drug delivery in cardiovascular disease. In view of the fast development in this field, we will also discuss the challenges of current methodologies for isolation, purification and fabrication of EVs and potential alternatives.

Engineered Extracellular Vesicles: Tailored-Made Nanomaterials for Medical Applications

Extracellular vesicles (EVs) are emerging as promising nanoscale therapeutics due to their intrinsic role as mediators of intercellular communication, regulating tissue development and homeostasis. The low immunogenicity and natural cell-targeting capabilities of EVs has led to extensive research investigating their potential as novel acellular tools for tissue regeneration or for the diagnosis of pathological conditions. However, the clinical use of EVs has been hindered by issues with yield and heterogeneity. From the modification of parental cells and naturally-derived vesicles to the development of artificial biomimetic nanoparticles or the functionalisation of biomaterials, a multitude of techniques have been employed to augment EVs therapeutic efficacy. This review will explore various engineering strategies that could promote EVs scalability and therapeutic effectiveness beyond their native utility. Herein, we highlight the current state-of-the-art EV-engineering techniques with discussion of opportunities and obstacles for each. This is synthesised into a guide for selecting a suitable strategy to maximise the potential efficacy of EVs as nanoscale therapeutics.

Cell-Derived Vesicles as TRPC1 Channel Delivery Systems for the Recovery of Cellular Respiratory and Proliferative Capacities

Pulsed electromagnetic fields (PEMFs) are capable of specifically activating a TRPC1-mitochondrial axis underlying cell expansion and mitohormetic survival adaptations. This study characterizes cell-derived vesicles (CDVs) generated from C2C12 murine myoblasts and shows that they are equipped with the sufficient molecular machinery to confer mitochondrial respiratory capacity and associated proliferative responses upon their fusion with recipient cells. CDVs derived from wild type C2C12 myoblasts include the cation-permeable transient receptor potential (TRP) channels, TRPC1 and TRPA1, and directly respond to PEMF exposure with TRPC1-mediated calcium entry. By contrast, CDVs derived from C2C12 muscle cells in which TRPC1 has been genetically knocked-down using CRISPR/Cas9 genome editing, do not. Wild type C2C12-derived CDVs are also capable of restoring PEMF-induced proliferative and mitochondrial activation in two C2C12-derived TRPC1 knockdown clonal cell lines in accordance to their endogenous degree of TRPC1 suppression. C2C12 wild type CDVs respond to menthol with calcium entry and accumulation, likewise verifying TRPA1 functional gating and further corroborating compartmental integrity. Proteomic and lipidomic analyses confirm the surface membrane origin of the CDVs providing an initial indication of the minimal cellular machinery required to recover mitochondrial function. CDVs hence possess the potential of restoring respiratory and proliferative capacities to senescent cells and tissues.

Platelets in Neurodegenerative Conditions-Friend or Foe?

It is now apparent that platelet function is more diverse than originally thought, shifting the view of platelets from blood cells involved in hemostasis and wound healing to major contributors to numerous regulatory processes across different tissues. Given their intriguing ability to store, produce and release distinct subsets of bioactive molecules, including intercellular signaling molecules and neurotransmitters, platelets may play an important role in orchestrating healthy brain function. Conversely, a number of neurodegenerative conditions have recently been associated with platelet dysfunction, further highlighting the tissue-independent role of these cells. In this review we summarize the requirements for platelet-neural cell communication with a focus on neurodegenerative diseases, and discuss the therapeutic potential of healthy platelets and the proteins which they release to counteract these conditions.