Biomimetic Exosomes: A New Generation of Drug Delivery System

Lactobacillus-derived artificial extracellular vesicles for skin rejuvenation and prevention of photo-aging

Extracellular vesicles (EVs) are small membrane-bound sacs released by cells that play crucial roles in intercellular communication. They transport biomolecules between cells and have both diagnostic and therapeutic potential. Artificial EVs, designed to mimic natural EVs, have been developed using various methods. In this study, Lactobacillus plantarum was used to create Lactobacillus-derived artificial EVs (LAEs) for skin rejuvenation and anti-aging. LAEs demonstrated monodispersity and effectively improved adverse gene expression and wound healing in fibroblasts. They also modulated aging-related genes and improved skin conditions in humans. Their simplicity, promptness, and lack of animal-derived sources make LAEs a promising alternative to natural EVs. LAEs have the potential to overcome the technical limitations of artificial EVs and advance EVs or exosome-based technologies for comprehensive skin rejuvenation.

Role of Nanomedicine in Transforming Pharmacotherapy for Substance Use Disorder (SUD)

The field of nanomedicine offers revolutionary potential to reshape the discovery and development of therapeutics for diverse human diseases. However, its application has been limited in improving Substance Use Disorders (SUDs), which represent a profound public health crisis, including major types such as opioid, alcohol, stimulant, and cannabis use disorders. Pharmacotherapy, a cornerstone of SUD management, has reduced morbidity, mortality, and the societal impact of addiction, though its efficacy has ranged from none to moderate. Thus, there is a major unmet need to transform SUD pharmacotherapy to curb the epidemic of addiction. This article explores the potential roles of nanomedicine-inspired precision-targeted drug delivery, sustained release, and combination therapies to increase therapeutic efficacy and minimize side effects. Additionally, it discusses innovative mechanisms that align with the neurobiological complexities of addiction and synergistic approaches that integrate nanomedicine with behavioral interventions, device-based therapies, and emerging modalities such as immunotherapy and neurostimulation. Despite these advancements, barriers such as treatment accessibility, adherence challenges, and inequitable resource distribution persist, particularly in underserved populations. By harnessing the transformative capabilities of nanomedicine and integrating it into holistic, equitable, and personalized care frameworks, this review highlights a path forward to revolutionize the SUD pharmacotherapy landscape. The article underscores the need for continued nano-SUD pharmacotherapy research and the development of strategies to alleviate the substantial burden of addiction on individuals, families, and society.

Leveraging nature's nanocarriers: Translating insights from extracellular vesicles to biomimetic synthetic vesicles for biomedical applications

Naturally occurring extracellular vesicles (EVs) and synthetic nanoparticles like liposomes have revolutionized precision diagnostics and medicine. EVs excel in biocompatibility and cell targeting, while liposomes offer enhanced drug loading capacity and scalability. The clinical translation of EVs is hindered by challenges including low yield and heterogeneity, whereas liposomes face rapid immune clearance and limited targeting efficiency. To bridge these gaps, biomimetic synthetic vesicles (SVs) have emerged as innovative platforms, combining the advantageous properties of EVs and liposomes. This review emphasizes critical aspects of EV biology, such as mechanisms of EV-cell interaction and source-dependent functionalities in targeting, immune modulation, and tissue regeneration, informing biomimetic SV engineering. We reviewed a broad array of biomimetic SVs, with a focus on lipid bilayered vesicles functionalized with proteins. These include cell-derived nanovesicles, protein-functionalized liposomes, and hybrid vesicles. By addressing current challenges and highlighting opportunities, this review aims to advance biomimetic SVs for transformative biomedical applications.

Development of non-viral targeted RNA delivery vehicles - a key factor in success of therapeutic RNA

Decade-long efforts in medicinal biotechnology have enabled large-scale in-vitro production of optimised therapeutic RNA constructs for stable in-vivo delivery and modify the expression of disease-related genes. The success of lipid nanoparticle-formulated mRNA vaccines against Severe acute respiratory syndrome Coronavirus-2 (SARS-Cov2) has opened a new era of RNA therapeutics and non-viral drug delivery systems. The major limiting factor in the clinical translation of RNA-based drugs is the availability of suitable delivery vehicles that can protect RNA payloads from degradation, offer controlled release, and pose minimal inherent toxicity. Unwanted immune response, payload size constraints, genome integration, and non-specific tissue targeting limit the application of conventional viral drug-delivery vehicles. This review summarises current research on nano-sized drug carriers, including lipid nanoparticles, polymer-based formulations, cationic nanoemulsion, and cell-penetrating peptides, for targeted therapeutic RNA delivery. Further, this paper highlights the biomimetic approaches (i.e. mimicking naturally occurring bio-compositions, molecular designs, and systems), including virus-like particles (VLPs), exosomes, and selective endogenous eNcapsidation (SEND) technology being explored as safer and more efficient alternatives.

Mesenchymal Stem-Cell-Derived Exosomes as Novel Drug Carriers in Anti-Cancer Treatment: A Myth or Reality?

Although cancer therapy has significantly advanced in recent decades, patients and healthcare professionals are still quite concerned about adverse effects due to the non-targeted nature of currently used chemotherapeutics. Results obtained in a large number of recently published experimental studies indicated that mesenchymal stem-cell-derived exosomes (MSC-Exos), due to their biocompatibility, ability to cross biological barriers, and inherent targeting capabilities, could be used as a promising drug-delivery system for anti-cancer therapies. Their lipid bilayer protects cargo of anti-cancer drugs, making them excellent candidates for the delivery of therapeutic agents. MSC-Exos could be engineered to express ligands specific for tumor cells and, therefore, could selectively deliver anti-cancer agents directly in malignant cells, minimizing side effects associated with chemotherapeutic-dependent injury of healthy cells. MSC-Exos can carry multiple therapeutic agents, including anti-cancer drugs, micro RNAs, and small bioactive molecules, which can concurrently target multiple signaling pathways, preventing tumor growth and progression and overcoming resistance of tumor cells to many standard chemotherapeutics. Accordingly, in this review article, we summarized current knowledge and future perspectives about the therapeutic potential of MSCs-Exos in anti-cancer treatment, opening new avenues for the targeted therapy of malignant diseases.

Evolution of antisense oligonucleotides: navigating nucleic acid chemistry and delivery challenges

INTRODUCTION

Antisense oligonucleotide (ASO) was established as a viable therapeutic option for genetic disorders. ASOs can target RNAs implicated in various diseases, including upregulated mRNA and pre-mRNA undergoing abnormal alternative splicing events. Therapeutic applications of ASOs have been proven with the Food and Drug Administration approval of several drugs in recent years. Earlier enzymatic stability and delivery remains a big challenge for ASOs. Introducing new chemical modifications and new formulations resolving the issues related to the nuclease stability and delivery of the ASOs. Excitingly, ASOs-based bioconjugates that target the hepatocyte have gained much attraction. Efforts are ongoing to increase the therapeutic application of the ASOs to the extrahepatic tissue as well.

AREA COVERED

We have briefly discussed the mechanism of ASOs, the development of new chemistries, and delivery strategies for ASO-based drug discovery and development. The discussion focuses more on the already approved ASOs and those in the clinical development stage.

EXPERT OPINION

To expand the clinical application of ASOs, continuous effort is required to develop precise delivery strategies for targeting extrahepatic tissue to minimize the off-target effects.

Edge advances in nanodrug therapies for osteoarthritis treatment

As global population and lifestyles change, osteoarthritis (OA) is becoming a major healthcare challenge world. OA, a chronic condition characterized by inflammatory and degeneration, often present with joint pain and can lead to irreversible disability. While there is currently no cure for OA, it is commonly managed using nonsteroidal anti-inflammatory drugs (NSAIDs), glucocorticoids, and glucosamine. Although these treatments can alleviate symptoms, it is difficult to effectively deliver and sustain therapeutic agents within joints. The emergence of nanotechnology, particularly in form of smart nanomedicine, has introduced innovative therapeutic approaches for OA treatment. Nanotherapeutic strategies offer promising advantages, including more precise targeting of affected areas, prolonged therapeutic effects, enhanced bioavailability, and reduced systemic toxicity compared to traditional treatments. While nanoparticles show potential as a viable delivery system for OA therapies based on encouraging lab-based and clinical trials results, there remails a considerable gap between current research and clinical application. This review highlights recent advances in nanotherapy for OA and explore future pathways to refine and optimize OA treatments strategies.

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.

Diagnostic and Therapeutic Roles of Extracellular Vesicles and Their Enwrapped ncRNAs in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a systemic inflammatory disease whose precise pathogenesis remains mysterious. The involvement of epigenetic regulation in the pathogenesis of RA is one of the most anticipated findings, among which non-coding RNAs (ncRNAs) hold great application promise as diagnostic and therapeutic biomarkers for RA. Extracellular vesicles (EVs) are a heterogeneous group of nano-sized, membrane-enclosed vesicles that mediate intercellular communication and substance exchange, especially the transfer of ncRNAs from donor cells, thereby regulating the functional activities and biological processes of recipient cells. In light of the significant correlation between EVs, ncRNAs, and RA, we first documented expression levels of EVs and their-encapsulated ncRNAs in RA individuals, and methodically discussed their-implicated signaling pathways and phenotypic changes. The last but not least, we paied special attention to the therapeutic benefits of gene therapy reagents specifically imitating or silencing candidate ncRNAs with exosomes as carriers on RA animal models, and briefly highlighted their clinical application advantage and foreground. In conclusion, the present review may be conducive to a deeper comprehension of the diagnostic and therapeutic roles of EVs-enwrapped ncRNAs in RA, with special emphasis on exosomal ncRNAs, which may offer hints for the monitoring and treatment of RA.

Advances in Engineering Circular RNA Vaccines

Engineered circular RNAs (circRNAs) are a class of single-stranded RNAs with head-to-tail covalently linked structures that integrate open reading frames (ORFs) and internal ribosome entry sites (IRESs) with the function of coding and expressing proteins. Compared to mRNA vaccines, circRNA vaccines offer a more improved method that is safe, stable, and simple to manufacture. With the rapid revelation of the biological functions of circRNA and the success of Severe Acute Respiratory Coronavirus Type II (SARS-CoV-2) mRNA vaccines, biopharmaceutical companies and researchers around the globe are attempting to develop more stable circRNA vaccines for illness prevention and treatment. Nevertheless, research on circRNA vaccines is still in its infancy, and more work and assessment are needed for their synthesis, delivery, and use. In this review, based on the current understanding of the molecular biological properties and immunotherapeutic mechanisms of circRNA, we summarize the current preparation methods of circRNA vaccines, including design, synthesis, purification, and identification. We discuss their delivery strategies and summarize the challenges facing the clinical application of circRNAs to provide references for circRNA vaccine-related research.

Engineering Exosomes for Therapeutic Applications: Decoding Biogenesis, Content Modification, and Cargo Loading Strategies

Exosomes emerge from endosomal invagination and range in size from 30 to 200 nm. Exosomes contain diverse proteins, lipids, and nucleic acids, which can indicate the state of various physiological and pathological processes. Studies have revealed the remarkable clinical potential of exosomes in diagnosing and prognosing multiple diseases, including cancer, cardiovascular disorders, and neurodegenerative conditions. Exosomes also have the potential to be engineered and deliver their cargo to a specific target. However, further advancements are imperative to optimize exosomes' diagnostic and therapeutic capabilities for practical implementation in clinical settings. This review highlights exosomes' diagnostic and therapeutic applications, emphasizing their engineering through simple incubation, biological, and click chemistry techniques. Additionally, the loading of therapeutic agents onto exosomes, utilizing passive and active strategies, and exploring hybrid and artificial exosomes are discussed.

Large-Scale Isolation of Milk Exosomes for Skincare

Exosomes are small membrane vesicles in a cell culture. They are secreted by most cells and originate from the endosomal pathway. A variety of proteins, lipids, and genetic materials have been shown to be carried by exosomes. Once taken up by neighboring or distant cells, the bioactive compounds in exosomes can regulate the condition of recipient cells. Typically, producing exosomes in large quantities requires cell culture, resulting in high production costs. However, exosomes are abundant in milk and can be isolated on a large scale at a low cost. In our study, we found that milk exosomes can promote the synthesis and reconstruction of stratum corneum lipids, enhance skin barrier function, and provide greater protection for the skin. Furthermore, milk exosomes have anti-inflammatory properties that can reduce skin irritation, redness, and other symptoms, giving immediate relief. They also exhibit antioxidant activity, which helps neutralize free radicals and slows down the skin aging process. Additionally, milk exosomes inhibit melanin production, aiding in skin whitening. Ongoing research has uncovered the benefits of milk exosomes for skin improvement and their application in cosmetics, skin healthcare, and other fields, and these applications are continuing to expand.

Exploiting Sound for Emerging Applications of Extracellular Vesicles

Extracellular vesicles are nano- to microscale, membrane-bound particles released by cells into extracellular space, and act as carriers of biomarkers and therapeutics, holding promising potential in translational medicine. However, the challenges remain in handling and detecting extracellular vesicles for disease diagnosis as well as exploring their therapeutic capability for disease treatment. Here, we review the recent engineering and technology advances by leveraging the power of sound waves to address the challenges in diagnostic and therapeutic applications of extracellular vesicles and biomimetic nanovesicles. We first introduce the fundamental principles of sound waves for understanding different acoustic-assisted extracellular vesicle technologies. We discuss the acoustic-assisted diagnostic methods including the purification, manipulation, biosensing, and bioimaging of extracellular vesicles. Then, we summarize the recent advances in acoustically enhanced therapeutics using extracellular vesicles and biomimetic nanovesicles. Finally, we provide perspectives into current challenges and future clinical applications of the promising extracellular vesicles and biomimetic nanovesicles powered by sound.

COTiR: Molecular Communication Model for Synthetic Exosome-Based Tissue Regeneration

Mesenchymal stem cell (MSC)-derived exosomes are recognized as an unparalleled therapy for tissue damage rendered by COVID-19 infection and subsequent hyper-inflammatory immune response. However, the natural targeting mechanism of exosomes is challenging to detect the damaged tissue over long diffusion distances efficiently. The coordinated movement of exosomes is desired for successful identification of target sites. In this work, we propose a molecular communication model, CoTiR, with a bio-inspired directional migration strategy (DMS) for guided propagation of exosomes to target the damaged tissues. The model includes directional propagation, reception, and regeneration of tissue. The proposed model has the potential to be used in designing efficient communication systems in the nanodomain. We compare the proposed model to the basic random propagation model and show the efficacy of our model regarding the detection of multiple targets and the detection time required. Simulation results indicate that the proposed model requires a shorter period of time for a similar number of exosomes to detect the targets compared to the basic random propagation model. Furthermore, the results reveal a 99.96% decrease in the collagen concentration in the absence of inflammatory cytokine molecules compared to the collagen concentration in the presence of inflammatory cytokine molecules.

Recent progress in nanotechnology-based drug carriers for resveratrol delivery

Resveratrol is a polyphenol with diverse pharmacological activities, but its clinical efficacy is limited due to low solubility/permeability, light-induced isomerization, auto-oxidation, and rapid metabolism. Nanodelivery systems, such as liposomes, polymeric nanoparticles, lipid nanocarriers, micelles, nanocrystals, inorganic nanoparticles, nanoemulsions, protein-based nanoparticles, exosomes, macrophages, and red blood cells (RBCs) have shown great potential for improving the solubility, biocompatibility, and therapeutic efficacy of resveratrol. This review comprehensively summarizes the recent advances in resveratrol nanoencapsulation and describes potential strategies to improve the pharmacokinetics of existing nanoformulations, enhance targeting, reduce toxicity, and increase drug release and encapsulation efficiency. The article also suggests that in order to avoid potential safety issues, resveratrol nanoformulations must be tested in vivo in a wide range of diseases.

Genetically Engineered-Cell-Membrane Nanovesicles for Cancer Immunotherapy

The advent of immunotherapy has marked a new era in cancer treatment, offering significant clinical benefits. Cell membrane as drug delivery materials has played a crucial role in enhancing cancer therapy because of their inherent biocompatibility and negligible immunogenicity. Different cell membranes are prepared into cell membrane nanovesicles (CMNs), but CMNs have limitations such as inefficient targeting ability, low efficacy, and unpredictable side effects. Genetic engineering has deepened the critical role of CMNs in cancer immunotherapy, enabling genetically engineered-CMN (GCMN)-based therapeutics. To date, CMNs that are surface modified by various functional proteins have been developed through genetic engineering. Herein, a brief overview of surface engineering strategies for CMNs and the features of various membrane sources is discussed, followed by a description of GCMN preparation methods. The application of GCMNs in cancer immunotherapy directed at different immune targets is addressed as are the challenges and prospects of GCMNs in clinical translation.

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.

Biomembrane-wrapped gene delivery nanoparticles for cancer therapy

As a promising strategy, gene delivery for cancer treatment accepts encouraging progress due to its high efficacy, low toxicity, and exclusive selectivity. However, the delivery efficiency, specific biological distribution, targeted uptake, and biosafety of naked nucleic acid agents still face serious challenges, which limit further clinical application. To overcome the above bottleneck, safe and efficient functional nanovectors are developed to improve the delivery efficiency of nucleic acid agents. In recent years, emerging membrane-wrapped biomimetic nanoparticles (MBNPs) based on the concept of "imitating nature" are well known for their advantages, such as low immunogenicity and long cycle time, and especially play a crucial role in improving the overall efficiency of gene delivery and reducing adverse reactions. Therefore, combining MBNPs and gene delivery is an effective strategy to enhance tumor treatment efficiency. This review presents the mechanism of gene therapy and the current obstacles to gene delivery. Remarkably, the latest development of gene delivery MBNPs and the strategies to overcome these obstacles are summarized. Finally, the future challenges and prospects of gene delivery MBNPs toward clinical transformation are introduced. The principal purpose of this review is to discuss the biomedical potential of gene delivery MBNPs for cancer therapy and to provide guidance for further enhancing the efficiency of tumor gene therapy.

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.

Extracellular Vesicles for Therapeutic Nucleic Acid Delivery: Loading Strategies and Challenges

Extracellular vesicles (EVs) are membrane vesicles released into the extracellular milieu by cells of various origins. They contain different biological cargoes, protecting them from degradation by environmental factors. There is an opinion that EVs have a number of advantages over synthetic carriers, creating new opportunities for drug delivery. In this review, we discuss the ability of EVs to function as carriers for therapeutic nucleic acids (tNAs), challenges associated with the use of such carriers in vivo, and various strategies for tNA loading into EVs.

Exosome-Based Carrier for RNA Delivery: Progress and Challenges

In the last few decades, RNA-based drugs have emerged as a promising candidate to specifically target and modulate disease-relevant genes to cure genetic defects. The key to applying RNA therapy in clinical trials is developing safe and effective delivery systems. Exosomes have been exploited as a promising vehicle for drug delivery due to their nanoscale size, high stability, high biocompatibility, and low immunogenicity. We reviewed and summarized the progress in the strategy and application of exosome-mediated RNA therapy. The challenges of exosomes as a carrier for RNA drug delivery are also elucidated in this article. RNA molecules can be loaded into exosomes and then delivered to targeted cells or tissues via various biochemical or physical approaches. So far, exosome-mediated RNA therapy has shown potential in the treatment of cancer, central nervous system disorders, COVID-19, and other diseases. To further exploit the potential of exosomes for RNA delivery, more efforts should be made to overcome both technological and logistic problems.

Advances in Purification, Modification, and Application of Extracellular Vesicles for Novel Clinical Treatments

Extracellular vesicles (EV) are membrane vesicles surrounded by a lipid bilayer membrane and include microvesicles, apoptotic bodies, exosomes, and exomeres. Exosome-encapsulated microRNAs (miRNAs) released from cancer cells are involved in the proliferation and metastasis of tumor cells via angiogenesis. On the other hand, mesenchymal stem cell (MSC) therapy, which is being employed in regenerative medicine owing to the ability of MSCs to differentiate into various cells, is due to humoral factors, including messenger RNA (mRNA), miRNAs, proteins, and lipids, which are encapsulated in exosomes derived from transplanted cells. New treatments that advocate cell-free therapy using MSC-derived exosomes will significantly improve clinical practice. Therefore, using highly purified exosomes that perform their original functions is desirable. In this review, we summarized advances in the purification, modification, and application of EVs as novel strategies to treat some diseases.

Engineered stem cell exosomes for oral and maxillofacial wound healing

Wound healing of the oral and maxillofacial area affects the quality of life and mental health of the patient; therefore, effective therapies are required to promote wound healing. However, traditional treatment methods have limited efficacy. Exosomes secreted by stem cells used for oral and maxillofacial wound healing have shown outstanding results. Stem cell-derived exosomes possess the regenerative and repair ability of stem cells. Moreover, they are nontumorigenic and have good biosafety. However, the application of natural stem cell exosomes is limited owing to their low yield, impurity, lack of targeting, and low drug delivery rate. Many modification methods have been developed to engineered stem cell exosomes with beneficial properties, such as modifying parent cells and directly processing stem cell exosomes. These methods include coincubation, genetic engineering, electroporation, ultrasound, and artificial synthesis of engineered stem cell exosomes. These engineered stem cell exosomes can cargo nucleic acids, proteins, and small molecules. This gives them anti-inflammatory and cell proliferation regulatory abilities and enables the targeted promotion of efficient soft tissue repair after trauma. Engineered stem cell exosomes can decrease inflammation, promote fibroblast proliferation, and angiogenesis, and decrease scar formation to promote oral and maxillofacial wound healing, including diabetic and burn wounds. Thus, engineered stem cell exosomes are an effective treatment that has the potential for oral and maxillofacial wound healing.

Hyaluronic Acid-Coated Bovine Milk Exosomes for Achieving Tumor-Specific Intracellular Delivery of miRNA-204

Cell type-specific drug delivery is a straightforward strategy to achieve targeted cancer therapy and reduce side effects. Hyaluronic acid (HA), an U.S. Food and Drug Administration (FDA)-approved biocompatible carbohydrate polymer, has been extensively employed as a targeting ligand for a drug delivery system due to its natural ability to bind to tumor cells overexpressing cluster of differentiation 44 (CD44) receptors. Here, we report the preparation and antitumor efficacy of HA-coated bovine milk exosomes (HA-mExo) for tumor-specific delivery of microRNA-204-5p mimics (miR-204). The exosome-based delivery formulation was prepared with miR-204 encapsulated inside the lumen and HA displayed outside the membrane. The resultant formulation of HA-mExo-miR204 was able to specifically target CD44-positive cancer cells, with a concomitant increase in the intracellular uptake of miR-204. Compared to the uncoated mExo-miR204 formulation, HA-mExo-miR204 showed significantly increased antitumor efficacy both in vitro and in vivo. Importantly, HA-mExo-miR204 showed excellent biocompatibility and did not cause significant systemic toxicity. Given that both HA and bovine milk exosomes are low-cost and highly accessible biogenic materials with broad biomedical applications, HA-decorated bovine milk exosomes can be proven to be a practical drug delivery system of RNA drugs for targeted cancer therapy.

Insights into CD24 and Exosome Physiology and Potential Role in View of Recent Advances in COVID-19 Therapeutics: A Narrative Review

Cluster of differentiation (CD) 24, a long-known protein with multifaceted functions, has gained attention as a possible treatment for Coronavirus Disease 19 (COVID-19) due to its known anti-inflammatory action. Extracellular vesicles (EVs), such as exosomes and microvesicles, may serve as candidate drug delivery platforms for novel therapeutic approaches in COVID-19 and various other diseases due to their unique characteristics. In the current review, we describe the physiology of CD24 and EVs and try to elucidate their role, both independently and as a combination, in COVID-19 therapeutics. CD24 may act as an important immune regulator in diseases with complex physiologies characterized by excessive inflammation. Very recent data outline a possible therapeutic role not only in COVID-19 but also in other similar disease states, e.g., acute respiratory distress syndrome (ARDS) and sepsis where immune dysregulation plays a key pathophysiologic role. On the other hand, CD24, as well as other therapeutic molecules, can be administered with the use of exosomes, exploiting their unique characteristics to create a novel drug delivery platform as outlined in recent clinical efforts. The implications for human therapeutics in general are huge with regard to pharmacodynamics, pharmacokinetics, safety, and efficacy that will be further elucidated in future randomized controlled trials (RCTs).