A facile magnetic extrusion method for preparing endosome-derived vesicles for cancer drug delivery

Bioinspired cellular membrane-derived vesicles for mRNA delivery

The rapid advancement of mRNA as vaccines and therapeutic agents in the biomedical field has sparked hope in the fight against untreatable diseases. Successful clinical application of mRNA therapeutics largely depends on the carriers. Recently, a new and exciting focus has emerged on natural cell-derived vesicles. These nanovesicles offer many functions, including enhanced drug delivery capabilities and immune evasion, thereby presenting a unique and promising platform for the effective and safe delivery of mRNA therapeutics. In this study, we summarize the characteristics and properties of biomimetic delivery systems for mRNA therapeutics. In particular, we discuss the unique features of cellular membrane-derived vesicles (CDVs) and the combination of synthetic nanovesicles with CDVs.

Extracellular vesicles in cancer: challenges and opportunities for clinical laboratories

Extracellular vesicles (EVs) are nano-sized particles secreted by most cells. They transport different types of biomolecules (nucleic acids, proteins, and lipids) characteristic of their tissue or cellular origin that can mediate long-distance intercellular communication. In the case of cancer, EVs participate in tumor progression by modifying the tumor microenvironment, favoring immune tolerance and metastasis development. Consequently, EVs have great potential in liquid biopsy for cancer diagnosis, prognosis and follow-up. In addition, EVs could have a role in cancer treatment as a targeted drug delivery system. The intense research in the EV field has resulted in hundreds of patents and the creation of biomedical companies. However, methodological issues and heterogeneity in EV composition have hampered the advancement of EV validation trials and the development of EV-based diagnostic and therapeutic products. Consequently, only a few EV biomarkers have moved from research to clinical laboratories, such as the ExoDx Prostate IntelliScore (EPI) test, a CLIA/FDA-approved EV prostate cancer diagnostic test. In addition, the number of large-scale multicenter studies that would clearly define biomarker performance is limited. In this review, we will critically describe the different types of EVs, the methods for their enrichment and characterization, and their biological role in cancer. Then, we will specially focus on the parameters to be considered for the translation of EV biology to the clinic laboratory, the advances already made in the field of EVs related to cancer diagnosis and treatment, and the issues still pending to be solved before EVs could be used as a routine tool in oncology.

Challenges and Promise for Glioblastoma Treatment through Extracellular Vesicle Inquiry

Glioblastoma (GB) is a rare but extremely aggressive brain tumor that significantly impacts patient outcomes, affecting both duration and quality of life. The protocol established by Stupp and colleagues in 2005, based on radiotherapy and chemotherapy with Temozolomide, following maximum safe surgical resection remains the gold standard for GB treatment; however, it is evident nowadays that the extreme intratumoral and intertumoral heterogeneity, as well as the invasiveness and tendency to recur, of GB are not compatible with a routine and unfortunately ineffective treatment. This review article summarizes the main challenges in the search for new valuable therapies for GB and focuses on the impact that extracellular vesicle (EV) research and exploitation may have in the field. EVs are natural particles delimited by a lipidic bilayer and filled with functional cellular content that are released and uptaken by cells as key means of cell communication. Furthermore, EVs are stable in body fluids and well tolerated by the immune system, and are able to cross physiological, interspecies, and interkingdom barriers and to target specific cells, releasing inherent or externally loaded functionally active molecules. Therefore, EVs have the potential to be ideal allies in the fight against GB and to improve the prognosis for GB patients. The present work describes the main preclinical results obtained so far on the use of EVs for GB treatment, focusing on both the EV sources and molecular cargo used in the various functional studies, primarily in vivo. Finally, a SWOT analysis is performed, highlighting the main advantages and pitfalls of developing EV-based GB therapeutic strategies. The analysis also suggests the main directions to explore to realize the possibility of exploiting EVs for the treatment of GB.

Research Advances of Engineered Exosomes as Drug Delivery Carrier

Exosomes are nanoscale vesicles secreted by living cells that have similar membrane composition to parental cells and carry a variety of proteins, lipids, and nucleic acids. Therefore, exosomes have certain biological activities and play an important role in intercellular communication. On the basis of its potential as a carrier for drug delivery systems, exosomes have been engineered to compensate for the shortage of natural exosomes through various engineering strategies for improving drug delivery efficiency, enhancing targeting to tissues and organs, and extending the circulating half-life of exosomes. This review focuses on the engineered exosomes loading drugs through different strategies, discussions on exosome surface modification strategies, and summarizes the advantages and disadvantages of different strategies. In addition, this review provides an overview of the recent applications of engineered exosomes in a number of refractory and relapsable diseases. This review has the potential to provide a reference for further research and development of engineered exosomes.

Plant exosome nanovesicles (PENs): green delivery platforms

Natural plants have been attracting increasing attention in biomedical research due to their numerous benefits. Plant exosome-derived vesicles, some of the plant's components, are small nanoscale vesicles secreted by plant cells. These vesicles are rich in bioactive substances and play significant roles in intercellular communication, information transfer, and maintaining homeostasis in organisms. They also hold promise for treating diseases, and their vesicular structures make them suitable carriers for drug delivery, with large-scale production feasible. Therefore, this paper aims to provide an overview of nanovesicles from different plant sources and their extraction methods. We also outline the biological activities of nanovesicles, including their anti-inflammatory, anti-viral, and anti-tumor properties, and systematically introduce their applications in drug delivery. These applications include transdermal delivery, targeted drug delivery, gene delivery, and their potential use in the modern food industry. This review provides new ideas and methods for future research on plant exosomes, including their empowerment by artificial intelligence and gene editing, as well as their potential application in the biomedicine, food, and agriculture industries.

Extracellular Vesicles Facilitate the Transportation of Nanoparticles within and between Cells for Enhanced Tumor Therapy

The interaction between nanoparticles and cells is closely associated with the therapeutic effects of nanomedicine. Nanoparticles could be transported among cells, but the process-related mechanism remains to be further explored. In this study, it was found that endocytosed cationic polymer nanoparticles (cNPs) could be excreted in an extracellular vesicle (EV)-coated form (cNP@EVs). It was deduced that cNPs may pass through early endosomes, multivesicular bodies (MVBs), and autophagic MVBs within cells. Moreover, a high level of autophagy facilitated the exocytosis process. Since EVs were the effective vehicles for conveying biological information and substances, cNP@EVs were proved to be efficient forms for the intercellular transportation of nanoparticles and have the potential as efficient biomimetic drug delivery systems. These properties endowed cNP@EVs with deep penetration and enhanced antitumor activity. Our findings provided a proof-of-concept for understanding the transfer process of nanoparticles among cells and may help us to further utilize EV-mediated transportation of nanoparticles, therefore, expanding its clinical application.

Engineered extracellular vesicles-like biomimetic nanoparticles as an emerging platform for targeted cancer therapy

Nanotechnology offers the possibility of revolutionizing cancer theranostics in the new era of precision oncology. Extracellular vesicles (EVs)-like biomimetic nanoparticles (EBPs) have recently emerged as a promising platform for targeted cancer drug delivery. Compared with conventional synthetic vehicles, EBPs have several advantages, such as lower immunogenicity, longer circulation time, and better targeting capability. Studies on EBPs as cancer therapeutics are rapidly progressing from in vitro experiments to in vivo animal models and early-stage clinical trials. Here, we describe engineering strategies to further improve EBPs as effective anticancer drug carriers, including genetic manipulation of original cells, fusion with synthetic nanomaterials, and direct modification of EVs. These engineering approaches can improve the anticancer performance of EBPs, especially in terms of tumor targeting effectiveness, stealth property, drug loading capacity, and integration with other therapeutic modalities. Finally, the current obstacles and future perspectives of engineered EBPs as the next-generation delivery platform for anticancer drugs are discussed.

The role of mesenchymal stem cells derived exosomes as a novel nanobiotechnology target in the diagnosis and treatment of cancer

Mesenchymal stem cells (MSCs), one of the most common types of stem cells, are involved in the modulation of the tumor microenvironment (TME). With the advancement of nanotechnology, exosomes, especially exosomes secreted by MSCs, have been found to play an important role in the initiation and development of tumors. In recent years, nanobiotechnology and bioengineering technology have been gradually developed to detect and identify exosomes for diagnosis and modify exosomes for tumor treatment. Several novel therapeutic strategies bioengineer exosomes to carry drugs, proteins, and RNAs, and further deliver their encapsulated cargoes to cancer cells through the properties of exosomes. The unique properties of exosomes in cancer treatment include targeting, low immunogenicity, flexibility in modification, and high biological barrier permeability. Nevertheless, the current comprehensive understanding of the roles of MSCs and their secreted exosomes in cancer development remain inadequate. It is necessary to better understand/update the mechanism of action of MSCs-secreted exosomes in cancer development, providing insights for better modification of exosomes through bioengineering technology and nanobiotechnology. Therefore, this review focuses on the role of MSCs-secreted exosomes and bioengineered exosomes in the development, progression, diagnosis, and treatment of cancer.

Exosome-Based Drug Delivery: Translation from Bench to Clinic

Exosome-based drug delivery is emerging as a promising field with the potential to revolutionize therapeutic interventions. Exosomes, which are small extracellular vesicles released by various cell types, have attracted significant attention due to their unique properties and natural ability to transport bioactive molecules. These nano-sized vesicles, ranging in size from 30 to 150 nm, can effectively transport a variety of cargoes, including proteins, nucleic acids, and lipids. Compared to traditional drug delivery systems, exosomes exhibit unique biocompatibility, low immunogenicity, and reduced toxicity. In addition, exosomes can be designed and tailored to improve targeting efficiency, cargo loading capacity, and stability, paving the way for personalized medicine and precision therapy. However, despite the promising potential of exosome-based drug delivery, its clinical application remains challenging due to limitations in exosome isolation and purification, low loading efficiency of therapeutic cargoes, insufficient targeted delivery, and rapid elimination in circulation. This comprehensive review focuses on the transition of exosome-based drug delivery from the bench to clinic, highlighting key aspects, such as exosome structure and biogenesis, cargo loading methods, surface engineering techniques, and clinical applications. It also discusses challenges and prospects in this emerging field.

Recent progress in the effect of magnetic iron oxide nanoparticles on cells and extracellular vesicles

At present, iron oxide nanoparticles (IONPs) are widely used in the biomedical field. They have unique advantages in targeted drug delivery, imaging and disease treatment. However, there are many things to pay attention to. In this paper, we reviewed the fate of IONPs in different cells and the influence on the production, separation, delivery and treatment of extracellular vesicles. It aims to provide cutting-edge knowledge related to iron oxide nanoparticles. Only by ensuring the safety and effectiveness of IONPs can their application in biomedical research and clinic be further improved.

Small extracellular vesicles: a novel drug delivery system for neurodegenerative disorders

Neurodegenerative diseases (NDs) have a slow onset and are usually detected late during disease. NDs are often difficult to cure due to the presence of the blood-brain barrier (BBB), which makes it difficult to find effective treatments and drugs, causing great stress and financial burden to families and society. Currently, small extracellular vesicles (sEVs) are the most promising drug delivery systems (DDSs) for targeted delivery of molecules to specific sites in the brain as a therapeutic vehicle due to their low toxicity, low immunogenicity, high stability, high delivery efficiency, high biocompatibility and trans-BBB functionality. Here, we review the therapeutic application of sEVs in several NDs, including Alzheimer's disease, Parkinson's disease, and Huntington's disease, discuss the current barriers associated with sEVs and brain-targeted DDS, and suggest future research directions.

Bioengineered exosomal-membrane-camouflaged abiotic nanocarriers: neurodegenerative diseases, tissue engineering and regenerative medicine

A bio-inspired strategy has recently been developed for camouflaging nanocarriers with biomembranes, such as natural cell membranes or subcellular structure-derived membranes. This strategy endows cloaked nanomaterials with improved interfacial properties, superior cell targeting, immune evasion potential, and prolonged duration of systemic circulation. Here, we summarize recent advances in the production and application of exosomal membrane-coated nanomaterials. The structure, properties, and manner in which exosomes communicate with cells are first reviewed. This is followed by a discussion of the types of exosomes and their fabrication methods. We then discuss the applications of biomimetic exosomes and membrane-cloaked nanocarriers in tissue engineering, regenerative medicine, imaging, and the treatment of neurodegenerative diseases. Finally, we appraise the current challenges associated with the clinical translation of biomimetic exosomal membrane-surface-engineered nanovehicles and evaluate the future of this technology.

A Meta-analysis on the Effectiveness of Extracellular Vesicles as Nanosystems for Targeted Delivery of Anticancer Drugs

While the efficacy of anticancer drugs is hampered by low bioavailability and systemic toxicity, the uncertainty remains whether encapsulation of these drugs into natural nanovesicles such as extracellular vesicles (EVs) could improve controlled drug release and efficacy for targeted tumor therapy. Thus, we performed a meta-analysis for studies reporting the efficacy of EVs as nanosystems to deliver drugs and nucleic acid, protein, and virus (NPV) to tumors using the random-effects model. The electronic search of articles was conducted through Cochrane, PubMed, Scopus, Science Direct, and Clinical Trials Registry from inception up till September 2022. The pooled summary estimate and 95% confidence interval of tumor growth inhibition, survival, and tumor targeting were obtained to assess the efficacy. The search yielded a total of 119 studies that met the inclusion criteria having only 1 clinical study. It was observed that the drug-loaded EV was more efficacious than the free drug in reducing tumor volume and weight with the standardized mean difference (SMD) of -1.99 (95% CI: -2.36, -1.63; p < 0.00001) and -2.12 (95% CI: -2.48, -1.77; p < 0.00001). Similarly, the mean estimate of tumor volume and weight for NPV were the following: SMD: -2.30, 95% CI: -3.03, -1.58; p < 0.00001 and SMD: -2.05, 95% CI: -2.79, -1.30; p < 0.00001. Treatment of tumors with EV-loaded anticancer agents also prolonged survival (HR: 0.15, 95% CI: 0.10, 0.22, p < 0.00001). Furthermore, EVs significantly delivered drugs to tumors as revealed by the higher concentration at the tumor site (SMD: -2.73, 95% CI: -3.77, -1.69; p < 0.00001). This meta-analysis revealed that EV-loaded drugs and NPV performed significantly better in tumor growth inhibition with improved survival than the free anticancer agents, suggesting EVs as safe nanoplatforms for targeted tumor therapy.

Exosome mimetics derived from bone marrow mesenchymal stem cells deliver doxorubicin to osteosarcoma in vitro and in vivo

Osteosarcoma is a bone tumor with a high incidence in children and adolescents. Chemotherapy for osteosarcoma is limited, and effective targeted drugs are urgently needed to treat osteosarcoma. Exosomes as a natural nano drug delivery platform have been widely studied and proven to have good drug delivery performance. However, the low production of exosomes hinders its development as a carrier. Exosome mimetics (EMs) as an alternative product of exosomes solve the problem of low production of exosomes and maintain the good performance of exosomes as carriers. In this study, bone marrow mesenchymal stem cells (BMSCs) were sequentially extruded to generate EMs to encapsulate doxorubicin (EM-Dox) to treat osteosarcoma. The results showed that we successfully prepared EMs of BMSC, and EM-Dox was prepared using an active-loading approach. Our engineered EM-Dox demonstrated significantly more potent tumor inhibition activity and fewer side effects than free doxorubicin. This novel biological nanomedicine system provides a promising opportunity to develop novel precision medicine for osteosarcoma.

High-Yield, Magnetic Harvesting of Extracellular Outer-Membrane Vesicles from Escherichia coli

Extracellular outer-membrane vesicles (OMVs) are attractive for use as drug nanocarriers, because of their high biocompatibility and ability to enter cells. However, widespread use is hampered by low yields. Here, a high-yield method for magnetic harvesting of OMVs from Escherichia coli is described. To this end, E. coli are grown in the presence of magnetic iron-oxide nanoparticles (MNPs). Uptake of MNPs by E. coli is low and does not increase secretion of OMVs. Uptake of MNPs can be enhanced through PEGylation of MNPs. E. coli growth in the presence of PEGylated MNPs increases bacterial MNP-uptake and OMV-secretion, accompanied by upregulation of genes involved in OMV-secretion. OMVs containing MNPs can be magnetically harvested at 60-fold higher yields than achieved by ultracentrifugation. Functionally, magnetically-harvested OMVs and OMVs harvested by ultracentrifugation are both taken-up in similar numbers by bacteria. Uniquely, in an applied magnetic field, magnetically-harvested OMVs with MNPs accumulate over the entire depth of an infectious biofilm. OMVs harvested by ultracentrifugation without MNPs only accumulate near the biofilm surface. In conclusion, PEGylation of MNPs is essential for their uptake in E. coli and yields magnetic OMVs allowing high-yield magnetic-harvesting. Moreover, magnetic OMVs can be magnetically targeted to a cargo delivery site in the human body.

Extracellular-Vesicle-Based Drug Delivery Systems for Enhanced Antitumor Therapies through Modulating the Cancer-Immunity Cycle

Although immunotherapy harnessing activity of the immune system against tumors has made great progress, the treatment efficacy remains limited in most cancers. Current anticancer immunotherapy is primarily based on T-cell-mediated cellular immunity, which highly relies on efficiency of triggering the cancer-immunity cycle, namely, tumor antigen release, antigen presentation by antigen presenting cells, T cell activation, recruitment and infiltration of T cells into tumors, and recognition and killing of tumor cells by T cells. Unfortunately, these immunotherapies are restricted by inefficient drug delivery and acting on only a single step of the cancer-immunity cycle. Due to high biocompatibility, low immunogenicity, intrinsic cell targeting, and easy chemical and genetic manipulation, extracellular vesicle (EV)-based drug delivery systems are widely used to amplify anticancer immune responses by serving as an integrated platform for multiple drugs or therapeutic strategies to synergistically activate several steps of cancer-immunity cycle. This review summarizes various mechanisms related to affecting cancer-immunity cycle disorders. Meanwhile, preparation and application of EV-based drug delivery systems in modulating cancer-immunity cycle are introduced, especially in the improvement of T cell recruitment and infiltration into tumors. Finally, opportunities and challenges of EV-based drug delivery systems in translational clinical applications are briefly discussed.

Harnessing the Therapeutic Potential of Extracellular Vesicles for Biomedical Applications Using Multifunctional Magnetic Nanomaterials

Extracellular vesicles (e.g., exosomes) carrying various biomolecules (e.g., proteins, lipids, and nucleic acids) have rapidly emerged as promising platforms for many biomedical applications. Despite their enormous potential, their heterogeneity in surfaces and sizes, the high complexity of cargo biomolecules, and the inefficient uptake by recipient cells remain critical barriers for their theranostic applications. To address these critical issues, multifunctional nanomaterials, such as magnetic nanomaterials, with their tunable physical, chemical, and biological properties, may play crucial roles in next-generation extracellular vesicles (EV)-based disease diagnosis, drug delivery, tissue engineering, and regenerative medicine. As such, one aims to provide cutting-edge knowledge pertaining to magnetic nanomaterials-facilitated isolation, detection, and delivery of extracellular vesicles and their associated biomolecules. By engaging the fields of extracellular vesicles and magnetic nanomaterials, it is envisioned that their properties can be effectively combined for optimal outcomes in biomedical applications.

Osteoblast/Osteoclast and Immune Cocktail Therapy of an Exosome/Drug Delivery Multifunctional Hydrogel Accelerates Fracture Repair

The osteoblast/osteoclast and M1/M2 macrophage ratios play critical roles in delayed fracture healing. Robust osteoblast differentiation and M2 macrophage polarization can substantiality promote fracture repair; however, the combined effect of these strategies has not been previously studied. In this study, we constructed a cocktail therapy to simultaneously regulate the osteoblast/osteoclast and M1/M2 macrophage balance. The cocktail therapy composed of a natural polymer hyaluronic-acid-based hydrogel (HA hydrogel, which has a tissue-adhesive, injectable, self-healing, anti-inflammation profile), engineered endothelial cell-derived exosomes (EC-Exos^miR-26a-5p), and APY29, an IRE-1α inhibitor. This allowed for specific delivery of EC-Exos^miR-26a-5p and APY29 for osteoblast/osteoclast and macrophage regulation, respectively. The results suggested that the cocktail therapy exerted pro-fracture repair effects with each of its components established as indispensable. The assessed cocktail therapy provides insight into synergistic strategies and is useful for developing more suitable pro-fracture repair therapy.

Exosomes Engineering and Their Roles as Therapy Delivery Tools, Therapeutic Targets, and Biomarkers

Exosomes are becoming increasingly important therapeutic biomaterials for use in a variety of therapeutic applications due to their unique characteristics, especially due to the ineffectiveness and cytotoxicity of some existing therapies and synthetic therapeutic nanocarriers. They are highly promising as carriers of drugs, genes, and other therapeutic agents that can be incorporated into their interior or onto their surface through various modification techniques to improve their targeting abilities. In addition, they are biocompatible, safe, and stable. The review focuses on different types of exosomes and methods of their preparation, including the incorporation of different kinds of cargo, especially for drug delivery purposes. In particular, their importance and effectiveness as delivery vehicles of various therapeutic agents for a variety of therapeutic applications, including different diseases and disorders such as cancer treatment, cardiovascular and neurodegenerative diseases, are emphasized. Administration routes of exosomes into the body are also included. A novelty in the article is the emphasis on global companies that are already successfully developing and testing such therapeutic biomaterials, with a focus on the most influential ones. Moreover, a comparison of the advantages and disadvantages of the various methods of exosome production is summarized for the first time.

Artificial exosomes for translational nanomedicine

Exosomes are lipid bilayer membrane vesicles and are emerging as competent nanocarriers for drug delivery. The clinical translation of exosomes faces many challenges such as massive production, standard isolation, drug loading, stability and quality control. In recent years, artificial exosomes are emerging based on nanobiotechnology to overcome the limitations of natural exosomes. Major types of artificial exosomes include 'nanovesicles (NVs)', 'exosome-mimetic (EM)' and 'hybrid exosomes (HEs)', which are obtained by top-down, bottom-up and biohybrid strategies, respectively. Artificial exosomes are powerful alternatives to natural exosomes for drug delivery. Here, we outline recent advances in artificial exosomes through nanobiotechnology and discuss their strengths, limitations and future perspectives. The development of artificial exosomes holds great values for translational nanomedicine.