Internalization of Exosomes through Receptor-Mediated Endocytosis

Characterization, microRNA profiling, and immunomodulatory role of plasma-derived exosomes from olive flounder (Paralichthys olivaceus) in response to viral hemorrhagic septicemia virus

Viral hemorrhagic septicemia virus (VHSV) is a highly pathogenic virus that frequently infects olive flounder (Paralichthys olivaceus), causing viral hemorrhagic septicemia (VHS), and posing a significant threat to global aquaculture. This study characterizes plasma-derived exosomes from olive flounder following VHSV challenge (VHSV-Exo) or phosphate buffered saline (PBS) injection (PBS-Exo), comparing their morphology, physicochemical properties, molecular profiles, and immunomodulatory functions. Both PBS-Exo (118.3 ± 8.6 nm) and VHSV-Exo (82.6 ± 5.9 nm) exhibited the typical cup-shaped morphology of exosomes. The successful isolation and purity of exosomes were confirmed by the presence of exosome markers (CD81, CD9, and CD63) and the absence of albumin. High-throughput sequencing identified 13 differentially expressed (DE) microRNAs (miRNAs) between PBS-Exo and VHSV-Exo, including six upregulated and seven downregulated miRNAs (log2 fold change ≥1 or ≤ -1). Toxicity assessments revealed that neither PBS-Exo nor VHSV-Exo were toxic to murine macrophage Raw 264.7 cells or zebrafish larvae at tested doses (up to 100 and 400 μg/mL, respectively). The absence of green fluorescence at 96 h post-treatment of VHSV-Exo indicated minimal reactive oxygen species generation, further supporting exosome safety. Functional studies demonstrated that both in vitro (Raw 264.7 cells) and in vivo (adult zebrafish) treatments with exosomes regulated immune-related genes and proteins expression. Notabaly, VHSV-Exo exhibited superior immunomodulatory effects, as evidenced by enhanced immune gene and protein expression. To our knowledge, this is the first study demonstrating the immunomodulatory potential of VHSV-Exo. These findings highlight VHSV-Exo as a promising immunomodulatory agent, with potential applications as a prophylactic vaccine candidate against VHSV infection in aquaculture.

Small milk-derived EVs: Suitable vehicles for oral drug delivery?

Current treatments for inflammatory bowel disease often fail due to systemic side effects, but bovine milk-derived extracellular vesicles (EVs) show promise for targeted delivery to inflamed gut tissue via the leaky gut effect. This study assessed the stability of EVs as drug carriers in simulated gastrointestinal (GI) fluids and their efficacy in a colitis mouse model. EVs were characterised after incubation in PBS at various pH levels, and their lipid bilayer stability in biorelevant GI fluids was evaluated using the polar probe laurdan. Two small molecules, acridine orange (lipophilic) and riboflavin (hydrophilic), were loaded into EVs to test their release under GI conditions, while unloaded EVs were investigated for therapeutic effect via oral gavage or rectal enema in a colitis mouse model. Although no significant changes in EVs' physical properties were observed at different pH levels, lipid bilayer damage was evident in acidic (p ≤ 0.05) and enzyme-rich environments (p ≤ 0.01). Acridine orange release was significant (p ≤ 0.05), butriboflavin remained encapsulated, and no therapeutic effect was observed with unloaded EVs in vivo. These results suggest that physical characterisation alone does not reflect EV stability, that bovine milk EVs have limited potential for oral drug delivery and are better suited for hydrophilic drugs.

Emerging roles of exosomal circRNAs in non-small cell lung cancer

Despite the prevalence of non-small cell lung cancer (NSCLC) is high, the limited early detection and management of these tumors are restricted since there is an absence of reliable and precise diagnostic biomarkers and therapeutic targets. Exosomes transport functional molecules for facilitating intercellular communication, especially in the tumor microenvironment, indicating their potential as cancer biomarkers and therapeutic targets. Circular RNA (circRNA), a type of non-coding RNA possessing a covalently closed loop structure, substantial abundance, and tissue-specific expression patterns, is stably enriched in exosomes. In recent years, significant breakthroughs have been made in research on exosomal circRNA in NSCLC. This review briefly introduces the biogenesis, characterizations, and functions of circRNAs and exosomes, and systematically describes the biological functions and mechanisms of exosomal circRNAs in NSCLC. In addition, this study summarizes their role in the progression of NSCLC and discusses their clinical significance as biomarkers and therapeutic targets for NSCLC.

A Review of the Neuroprotective Properties of Exosomes Derived from Stem Cells and Exosome-Coated Nanoparticles for Treating Neurodegenerative Diseases and Stroke

Neurological diseases, including neurodegenerative disorders and stroke, represent significant medical challenges due to their complexity and the limitations of current treatment approaches. This review explores the potential of stem cell (SC)-derived exosomes (Exos) as a transformative therapeutic strategy for these diseases. Exos, especially those derived from SCs, exhibit natural targeting ability, biocompatibility, and the capacity to cross the blood-brain barrier (BBB), making them ideal vehicles for drug delivery. This review provides an in-depth discussion of the properties and advantages of SC-Exos. It highlights their potential synergistic benefits in therapeutic approaches to treat neurological diseases. This article discusses the mechanisms of action of SC-Exos, highlighting their ability to target specific cells, modulate disease pathways, and provide controlled release of therapeutic agents. Applications in specific neurological disorders have been investigated, demonstrating the potential to improve outcomes in conditions such as Alzheimer's Disease (AD), Parkinson's Disease (PD), and stroke. Moreover, Exos-coated nanoparticles (NPs) combine the natural properties of Exos with the multifunctionality of NPs. This integration takes advantage of exosome membrane biocompatibility and targeting capabilities while preserving NPs' beneficial features, such as drug loading and controlled release. As a result, Exos-coated NPs may enhance the precision, efficacy, and safety of therapeutic interventions. In conclusion, SC-Exos represent a promising and innovative approach to treating neurological diseases.

Uptake of small extracellular vesicles by recipient cells is facilitated by paracrine adhesion signaling

Small extracellular vesicles (sEVs) play crucial roles in intercellular communication. However, the internalization of individual sEVs by recipient cells has not been directly observed. Here, we examined these mechanisms using state-of-the-art imaging techniques. Single-molecule imaging shows that tumor-derived sEVs can be classified into several subtypes. Simultaneous single-sEV particle tracking and observation of super-resolution movies of membrane invaginations in living cells reveal that all sEV subtypes are internalized via clathrin-independent endocytosis mediated by galectin-3 and lysosome-associated membrane protein-2C, while some subtypes that recruited raft markers are internalized through caveolae. Integrin β1 and talin-1 accumulate in recipient cell plasma membranes beneath all sEV subtypes. Paracrine, but not autocrine, sEV binding triggers Ca2+ mobilization induced by the activation of Src family kinases and phospholipase Cγ. Subsequent Ca2+-induced activation of calcineurin-dynamin promotes sEV internalization, leading to the recycling pathway. Thus, we clarified the detailed mechanisms of sEV internalization driven by paracrine adhesion signaling.

An anti-CD19-exosome delivery system navigates the blood-brain barrier for targeting of central nervous system lymphoma

BACKGROUND

High-dose methotrexate (HD-MTX) serves as the cornerstone of central nervous system lymphoma (CNSL) treatment, but its efficacy is limited due to low blood-brain barrier (BBB) penetration and adverse effects. This study is focused on an exosome-based drug delivery approach aimed at enhancing BBB permeability, thereby reducing the required dosage of methotrexate (MTX) while ensuring specific targeting of CNSL.

METHODS

Human adipose-derived mesenchymal stem cells (hAMSCs) were modified with a lentiviral vector encoding anti-CD19, incorporated into exosomes characterized by colloidal gold immunoelectron microscopy and Nano flow cytometry. MTX loaded into anti-CD19-Exos via co-incubation, assessed for loading and encapsulation efficiencies using HPLC. In vitro BBB model constructed using hCMEC/D3 and astrocytes to investigate BBB permeability. In vivo efficacy of anti-CD19-Exo-MTX evaluated in intracranial CNSL models using MRI. Biodistribution tracked with DiR-labeled exosomes, drug concentration in CSF measured by HPLC. LC-MS/MS identified and characterized exosomal proteins analyzed using GO Analysis. Neuroprotective effects of exosomal proteins assessed with TUNEL and Nissl staining on hippocampal neurons in CNSL models. Liver and kidney pathology, blood biochemical markers, and complete blood count evaluated exosomal protein effects on organ protection and MTX-induced myelosuppression.

RESULTS

We generated anti-CD19-Exo derived from hAMSCs. These adapted exosomes effectively encapsulated MTX, enhancing drug accessibility within lymphoma cells and sustained intracellular accumulation over an extended period. Notably, anti-CD19-Exo-MTX interacted with cerebrovascular endothelial cells and astrocytes of the BBB, leading to endocytosis and facilitating the transportation of MTX across the barrier. Anti-CD19-Exo-MTX outperformed free MTX in vitro, exhibiting a more potent lymphoma-suppressive effect (P < 0.05). In intracranial orthotopic CNSL models, anti-CD19-Exo-MTX exhibited a significantly reduced disease burden compared to both the MTX and Exo-MTX groups, along with prolonged overall survival (P < 0.05). CSF drug concentration analysis demonstrated enhanced stability and longer-lasting drug levels for anti-CD19-Exo-MTX. Anti-CD19-Exo-MTX exhibited precise CNSL targeting with no organ toxicity. Notably, our study highlighted the functional potential of reversal effect of hAMSCs-exosomes on MTX-induced neurotoxicity, hepatic and renal impairment, and myelosuppression.

CONCLUSIONS

We present anti-CD19-Exo-MTX as a promising exosome-based drug delivery platform that enhances BBB permeability and offers specific targeting for effective CNSL treatment with reduced adverse effects.

hESC-derived extracellular vesicles enriched with MFGE-8 and the GSH redox system act as senotherapeutics for neural stem cells in ischemic stroke

Human embryonic stem cells (hESCs) and their extracellular vesicles (EVs) hold significant potential for tissue repair and regeneration. Neural stem cells (NSCs) in the adult brain often acquire senescent phenotypes after ischemic injuries, releasing neurodegenerative senescence-associated secretory phenotype factors. In this study, we investigated the senotherapeutic effects of hESC-EVs on NSCs and confirmed their neuroprotective effects in neurons via rejuvenation of NSC secretions. Proteomic profiling of hESC-EVs identified MFGE-8 as a critical bridging molecule to NSCs. We also found that the glutathione (GSH) redox system is a key contributor to the therapeutic antioxidant activity of hESC-EVs. Additionally, EVs produced by the hypoxic preconditioning of hESCs (hESC-HypoxEVs) exhibited reinforced GSH redox capacity and further enhanced the senotherapeutic effects on NSCs compared to naïve hESC-EVs. We also demonstrated that administration of hESC-HypoxEVs, precoated with MFGE-8, significantly increased the populations of NSCs and newborn neurons in the subventricular zone of the brain and improved sensorimotor functions in a rat model of ischemic stroke. Our study suggests that combining hESC-HypoxEVs with MFGE-8 may serve as an effective therapeutic modality for reversing senescence and enhancing the neurogenic potential of NSCs to treat neurodegenerative diseases.

Exploring the ncRNA landscape in exosomes: Insights into wound healing mechanisms and therapeutic applications

Exosomal non-coding RNAs (ncRNAs), including miRNAs, lncRNAs, and circRNAs, have emerged as crucial modulators in cellular signaling, influencing wound healing processes. Stem cell-derived exosomes, which serve as vehicles for these ncRNAs, show remarkable therapeutic potential due to their ability to modulate wound healing stages, from initial inflammation to collagen formation. These ncRNAs act as molecular signals, regulating gene expression and protein synthesis necessary for cellular responses in healing. Wound healing is a complex, staged process involving inflammation, hemostasis, fibroblast proliferation, angiogenesis, and tissue remodeling. Stem cell-derived exosomal ncRNAs enhance these stages by reducing excessive inflammation, promoting anti-inflammatory responses, guiding fibroblast and keratinocyte maturation, enhancing vascularization, and ensuring organized collagen deposition. Their molecular cargo, particularly ncRNAs, specifically targets pathways to aid chronic wound repair and support scarless regeneration. This review delves into the unique composition and signaling roles of Stem cell-derived exosomes and ncRNAs, highlighting their impact across wound healing stages and their potential as innovative therapeutics. Understanding the interaction between exosomal ncRNAs and cellular signaling pathways opens new avenues in regenerative medicine, positioning Stem cell-derived exosomes and their ncRNAs as promising molecular-level interventions in wound healing.

Substrate stiffness regulates the proliferation and inflammation of chondrocytes and macrophages through exosomes

Osteoarthritis (OA) progression is characterized by decreased cartilage stiffness and degradation of the extracellular matrix (ECM), which significantly influence cartilage behavior and fate. In contrast, processes such as chondrocyte calcification and aging often result in increased stiffness. Despite extensive studies on how ECM stiffness regulates cellular functions, the impact of substrate stiffness on the cartilage microenvironment and intercellular communications remains not well understood. Using tunable stiffness Gelatin methacryloyl (GelMA) hydrogel, we demonstrated that a potential optimal substrate stiffness can promote maximal chondrocyte proliferation and exosome secretion. The exogenous addition of stiffness-tuned exosomes induced significant changes in chondrocyte morphology, proliferation, migration, and inflammation. Notably, blocking Yes-associated protein (YAP) synthesis negated the proliferation enhancement induced by exosomes from chondrocytes cultured on medium stiffness substrates (ExoMedium), confirming that substrate stiffness regulates cell proliferation through exosomes by modulating YAP expression and its nuclear localization. Moreover, our study revealed that exosomes from medium stiffness substrates-mimicking normal cartilage stiffness-not only reduce inflammation in chondrocytes but also shift macrophage polarization from M1 to M2. Conversely, exosomes from soft stiffness substrates, akin to osteoarthritic tissue, exacerbate chondrocytes inflammation and M1 macrophage polarization. These findings highlight the crucial role of stiffness-tuned exosomes in OA progressing, affecting chondrocyte proliferation, migration, inflammation and macrophage polarization, and provide new insights into the potential novel treatment strategies using engineered scaffolds and exosomes. STATEMENT OF SIGNIFICANCE: Osteoarthritis (OA) is a prevalent degenerative joint disease characterized by decreased cartilage stiffness and degradation of the extracellular matrix (ECM). While some studies suggest that increased substrate stiffness enhances cell proliferation, others have reported the opposite effect. Whether there exists an optimal matrix stiffness that promotes chondrocytes anabolism and how matrix stiffness regulates the cartilage microenvironment and intercellular communications remain unclear. Utilizing tunable stiffness Gelatin methacryloyl (GelMA) hydrogel, this study demonstrated that a potential optimal substrate stiffness can maximize chondrocyte proliferation and exosome secretion. The introduction of stiffness-tuned exosomes induced significant changes in chondrocyte and macrophage proliferation, migration, and inflammation, offering new insights into OA progression and highlighting their potential as a promising therapeutic strategy for osteoarthritis treatment and tissue regeneration.

Exosomes and breast cancer angiogenesis; Highlights in intercellular communication

Breast cancer (BC) is a prevalent and highly lethal cancer in females. Like other cancer types, the intricate cellular and molecular heterogeneity leads to the variation of therapeutic outcomes. The development and progression of blood vessels increase the tumor cell expansion and metastasis to remote sites. Based on several pieces of scientific data, different mediators and cells are involved in the promotion of angiogenesis into the tumor parenchyma. Recent data have indicated the critical role of extracellular vesicles, especially exosomes (Exos), in the transfer of angiogenesis molecules between the BC cells. Due to unique physicochemical properties, and the transfer of certain signaling molecules, Exos are at the center of attention in terms of biomarkers and therapeutic bullets in cancer patients. Along with these statements, understanding the modulatory role of Exos in BC angiogenesis seems critical in the clinical setting. Here, the mechanisms by which BC cells can orchestrate the angiogenesis phenomenon via Exos are discussed in detail. The present study can help us to understand the pro-/anti-angiogenesis role of Exos in BC and to design better oncostatic strategies.

Hybrid Nanoparticle Engineered with Transforming Growth Factor -β1-Overexpressed Extracellular Vesicle and Cartilage-Targeted Anti-Inflammatory Liposome for Osteoarthritis

Extracellular vesicles (EVs) possess the characteristics of their parent cells, based on which various studies have actively investigated treatments for diseases using mesenchymal stem cell-derived EVs due to their regenerative activity. Furthermore, in recent years, there have been significant efforts to engineer EVs to improve their native activities and integrate additional functions. Although both endogenous and exogenous methods are used for engineering EVs, endogenous methods may pose the problem of administering substances to cells undergoing metabolic changes, which can cause potential side effects. In addition, exogenous methods may have the limitation of losing beneficial factors inside EVs due to membrane disruption during engineering processes. Surface modification of EVs may also impair efficiency due to the presence of proteins on the EV surface. Therefore, in this study, a stable and efficient engineering method was achieved through the ethanol-mediated hybridization of EVs and functionalized lipid nanoparticles (LNPs) with a fusogenic lipid component. During hybridization, the internal bioactive factors and targeting moiety were maintained to possess the characteristics of both LNPs and EVs. The Ab-Hybrid, which was successfully synthesized through hybridization with nicotinamide-encapsulated and Col2A1 antibody-modified liposome and Transforming growth factor-β1 (TGF-β1)-overexpressed EVs, was administered to osteoarthritis (OA)-induced rats undergoing the destabilization of the medial meniscus surgery. Ultimately, the Ab-Hybrid demonstrated excellent chondroprotective and anti-inflammatory effects with targeting and long-lasting properties in OA lesions. We anticipate that this approach for manufacturing hybrid particles will serve as a valuable EV engineering method and a versatile platform technology applicable to various diseases.

Organoids and organoid extracellular vesicles-based disease treatment strategies

Organoids are "mini-organs" that self-organize and differentiate from stem cells under in vitro 3D culture conditions, mimicking the spatial structure and function of tissues in vivo. Extracellular vesicles (EVs) are nanoscale phospholipid bilayer vesicles secreted by living cells, rich in bioactive molecules, with excellent biocompatibility and low immunogenicity. Compared to EVs, organoid-derived EVs (OEVs) exhibit higher yield and enhanced biological functions. Organoids possess stem cell characteristics, and OEVs are capable of delivering active substances, making both highly promising for medical applications. In this review, we provide an overview of the fundamental biological principles of organoids and OEVs, and discuss their current applications in disease treatment. We then focus on the differences between OEVs and traditional EVs. Subsequently, we present methods for the engineering modification of OEVs. Finally, we critically summarize the advantages and challenges of organoids and OEVs. In conclusion, we believe that a deeper understanding of organoids and OEVs will provide innovative solutions to complex diseases.

Endocytic pathways and metabolic fate of colloidal bismuth subcitrate in human renal cells

Bismuth compounds, particularly colloidal bismuth subcitrate (CBS), have been widely used in the treatment of gastrointestinal diseases. However, overdose of CBS has been linked to cases of acute renal failure, primarily due to the intracellular accumulation of bismuth in the kidney. To date, the detailed mechanisms of CBS internalization and its metabolic fate remain unclear. In this study, CBS was characterized as a type of nano-object using transmission electron microscopy and dynamic light scattering. Renal cells internalized CBS primarily via clathrin-mediated endocytosis in an active transport manner. Gene knockdown techniques revealed that CBS binds to the transferrin receptor likely through complexing with transferrin before cellular uptake. Once internalized, CBS was sorted into early endosomes, late endosomes, and lysosomes, mediated by microtubules and the Golgi apparatus. Additionally, differentially expressed genes analysis revealed that CBS endocytosis stimulated oxidative stress, significantly affecting the metabolism of glutathione and cysteine within cells. This led to the formation of black bismuth sulfide particles as a result of CBS conjugating with intracellular glutathione. These findings provide crucial insights into the cellular mechanisms underlying excessive CBS exposure, which is essential for understanding and potentially mitigating the risks associated with the use of bismuth compounds in medical treatments.

Extracellular vesicles in cancer: golden goose or Trojan horse

Intercellular communication can be mediated by direct cell-to-cell contact and indirect interactions through secretion of soluble chemokines, cytokines, and growth factors. Extracellular vesicles (EVs) have emerged as important mediators of cell-to-cell and cell-to-environment communications. EVs from tumor cells, immune cells, and stromal cells can remodel the tumor microenvironment and promote cancer cell survival, proliferation, metastasis, immune evasion, and therapeutic resistance. Most importantly, EVs as natural nanoparticles can be manipulated to serve as a potent delivery system for targeted cancer therapy. EVs can be engineered or modified to improve their ability to target tumors and deliver therapeutic substances, such as chemotherapeutic drugs, nucleic acids, and proteins, for the treatment of cancer. This review provides an overview of the biogenesis and recycling of EVs, discusses their roles in cancer development, and highlights their potential as a delivery system for targeted cancer therapy.

Enhancing Cartilage Repair: Surgical Approaches, Orthobiologics, and the Promise of Exosomes

Treating cartilage damage is challenging as its ability for self-regeneration is limited. Left untreated, it can progress to osteoarthritis (OA), a joint disorder characterized by the deterioration of articular cartilage and other joint tissues. Surgical options, such as microfracture and cell/tissue transplantation, have shown promise as techniques to harness the body's endogenous regenerative capabilities to promote cartilage repair. Nonetheless, these techniques have been scrutinized due to reported inconsistencies in long-term outcomes and the tendency for the defects to regenerate as fibrocartilage instead of the smooth hyaline cartilage native to joint surfaces. Orthobiologics are medical therapies that utilize biologically derived substances to augment musculoskeletal healing. These treatments are rising in popularity because of their potential to enhance surgical standards of care. More recent developments in orthobiologics have focused on the role of exosomes in articular cartilage repair. Exosomes are nano-sized extracellular vesicles containing cargo such as proteins, lipids, and nucleic acids, and are known to facilitate intercellular communication, though their regenerative potential still needs to be fully understood. This review aims to demonstrate the advancements in cartilage regeneration, highlight surgical and biological treatment options, and discuss the recent strides in understanding the precise mechanisms of action involved.

Vascularized platforms for investigating cell communication via extracellular vesicles

The vascular network plays an essential role in the maintenance of all organs in the body via the regulated delivery of oxygen and nutrients, as well as tissue communication via the transfer of various biological signaling molecules. It also serves as a route for drug administration and affects pharmacokinetics. Due to this importance, engineers have sought to create physiologically relevant and reproducible vascular systems in tissue, considering cell-cell and extracellular matrix interaction with structural and physical conditions in the microenvironment. Extracellular vesicles (EVs) have recently emerged as important carriers for transferring proteins and genetic material between cells and organs, as well as for drug delivery. Vascularized platforms can be an ideal system for studying interactions between blood vessels and EVs, which are crucial for understanding EV-mediated substance transfer in various biological situations. This review summarizes recent advances in vascularized platforms, standard and microfluidic-based techniques for EV isolation and characterization, and studies of EVs in vascularized platforms. It provides insights into EV-related (patho)physiological regulations and facilitates the development of EV-based therapeutics.

Small Differences and Big Changes: The Many Variables of MicroRNA Expression and Function in the Brain

MicroRNAs are emerging as crucial regulators within the complex, dynamic environment of the synapse, and they offer a promising new avenue for the treatment of neurological disease. These small noncoding RNAs modify gene expression in several ways, including posttranscriptional modulation via binding to complementary and semicomplementary sites on target mRNAs. This rapid, finely tuned regulation of gene expression is essential to meet the dynamic demands of the synapse. Here, we provide a detailed review of the multifaceted world of synaptic microRNA regulation. We discuss the many mechanisms by which microRNAs regulate gene expression at the synapse, particularly in the context of neuronal plasticity. We also describe the various factors, such as age, sex, and neurological disease, that can influence microRNA expression and activity in neurons. In summary, microRNAs play a crucial role in the intricate and quickly changing functional requirements of the synapse, and context is essential in the study of microRNAs and their potential therapeutic applications.

Modulated Cell Internalization Behavior of Icosahedral DNA Framework with Programmable Surface Modification

Surface modification could enhance the cell internalization efficiency of nanovehicles for targeted gene or drug delivery. However, the influence of surface modification parameters, including recognition manners, valences, and patterns, is often clouded, especially for the endocytosis of DNA nanostructures in customized shapes. Focusing on an icosahedral DNA framework, we systematically programmed three distinct types of ligands with diverse valence and spatial distribution on their outer surface to study the internalization efficiency, endocytic pathways, and postinternalization fate. The comparison in different aspects of parameters deepens our understanding of the intricate relationship between surface modification and cell entry behavior, offering insights crucial for designing and optimizing DNA framework nanostructures for potent cell-targeted purposes.

Copper/Tin Nanocomposites-Loaded Exosomes Induce Apoptosis and Cell Cycle Arrest at G0/G1 Phase in Skin Cancer Cell Line

This study aims to explore the efficacy of Copper/Tin (CuS/SnS) nanocomposites loaded into exosomes against skin cancer A431 cell line. CuS/SnS nanocomposites (S1, S2, S3) were synthesized and characterized, then loaded into exosomes (Exo) (S1-Exo, S2-Exo and S3-Exo) and characterized. After that, the loaded samples were investigated in vitro against A431 using cytotoxicity, apoptosis, and cell cycle assays. CuS/SnS nanocomposites were indexed to hexagonal CuS structure and orthorhombic α-SnS phase and showed nano-rode shape. The exosomes loaded with nanocomposites were regular and rounded within the size of 120 nm, with no signs of broken exosomes or leakage of their contents. The cytotoxicity assay indicated the enhanced cytotoxic of S1-Exo versus the free nano-form S1 on A431. Interestingly, S1-Exo recorded 1.109 times more than DOX in its anti-skin cancer capacity. Moreover, S1-Exo recorded 40.2 % for early apoptosis and 22.1 % for late apoptosis. Furthermore, it displayed impact in arresting the cancer cell cycle at G0/G1 phase and reducing G2/M phase. Noteworthy, loaded nanocomposites were safe against normal HSF skin cells. In conclusion, the loaded CuS/SnS nanocomposites into the exosomes could be of great potential as anti-skin cancer candidates through induction of apoptosis and promotion of the cell cycle arrest at G0/G1 phase.

Exosomes: a review of biologic function, diagnostic and targeted therapy applications, and clinical trials

Exosomes are extracellular vesicles generated by all cells and they carry nucleic acids, proteins, lipids, and metabolites. They mediate the exchange of substances between cells,thereby affecting biological properties and activities of recipient cells. In this review, we briefly discuss the composition of exocomes and exosome isolation. We also review the clinical applications of exosomes in cancer biology as well as strategies in exosome-mediated targeted drug delivery systems. Finally, the application of exosomes in the context of cancer therapeutics both in practice and literature are discussed.

In vivo Fate of Targeted Drug Delivery Carriers

This review aimed to systematically investigate the intracellular and subcellular fate of various types of targeting carriers. Upon entering the body via intravenous injection or other routes, a targeting carrier that can deliver therapeutic agents initiates their journey. If administered intravenously, the carrier initially faces challenges presented by the blood circulation before reaching specific tissues and interacting with cells within the tissue. At the subcellular level, the car2rier undergoes processes, such as drug release, degradation, and metabolism, through specific pathways. While studies on the fate of 13 types of carriers have been relatively conclusive, these studies are incomplete and lack a comprehensive analysis. Furthermore, there are still carriers whose fate remains unclear, underscoring the need for continuous research. This study highlights the importance of comprehending the in vivo and intracellular fate of targeting carriers and provides valuable insights into the operational mechanisms of different carriers within the body. By doing so, researchers can effectively select appropriate carriers and enhance the successful clinical translation of new formulations.

Exosome for mRNA delivery: strategies and therapeutic applications

Messenger RNA (mRNA) has emerged as a promising therapeutic molecule with numerous clinical applications in treating central nervous system disorders, tumors, COVID-19, and other diseases. mRNA therapies must be encapsulated into safe, stable, and effective delivery vehicles to preserve the cargo from degradation and prevent immunogenicity. Exosomes have gained growing attention in mRNA delivery because of their good biocompatibility, low immunogenicity, small size, unique capacity to traverse physiological barriers, and cell-specific tropism. Moreover, these exosomes can be engineered to utilize the natural carriers to target specific cells or tissues. This targeted approach will enhance the efficacy and reduce the side effects of mRNAs. However, difficulties such as a lack of consistent and reliable methods for exosome purification and the efficient encapsulation of large mRNAs into exosomes must be addressed. This article outlines current breakthroughs in cell-derived vesicle-mediated mRNA delivery and its biomedical applications.

Macrophages treated with interferons induce different responses in lymphocytes via extracellular vesicles

Limited information exists regarding the impact of interferons (IFNs) on the information carried by extracellular vesicles (EVs). This study aimed at investigating whether IFN-α2b, IFN-β, IFN-γ, and IFN-λ1/2 modulate the content of EVs released by primary monocyte-derived macrophages (MDM). Small-EVs (sEVs) were purified by size exclusion chromatography from supernatants of MDM treated with IFNs. To characterize the concentration and dimensions of vesicles, nanoparticle tracking analysis was used. SEVs surface markers were examined by flow cytometry. IFN treatments induced a significant down-regulation of the exosomal markers CD9, CD63, and CD81 on sEVs, and a significant modulation of some adhesion molecules, major histocompatibility complexes and pro-coagulant proteins, suggesting IFNs influence biogenesis and shape the immunological asset of sEVs. SEVs released by IFN-stimulated MDM also impact lymphocyte function, showing significant modulation of lymphocyte activation and IL-17 release. Altogether, our results show that sEVs composition and activity are affected by IFN treatment of MDM.

Integrated proteomic, phosphoproteomic, and N-glycoproteomic analyses of small extracellular vesicles from C2C12 myoblasts identify specific PTM patterns in ligand-receptor interactions

Small extracellular vesicles (sEVs) are important mediators of intercellular communication by transferring of functional components (proteins, RNAs, and lipids) to recipient cells. Some PTMs, including phosphorylation and N-glycosylation, have been reported to play important role in EV biology, such as biogenesis, protein sorting and uptake of sEVs. MS-based proteomic technology has been applied to identify proteins and PTM modifications in sEVs. Previous proteomic studies of sEVs from C2C12 myoblasts, an important skeletal muscle cell line, focused on identification of proteins, but no PTM information on sEVs proteins is available.In this study, we systematically analyzed the proteome, phosphoproteome, and N-glycoproteome of sEVs from C2C12 myoblasts with LC-MS/MS. In-depth analyses of the three proteomic datasets revealed that the three proteomes identified different catalogues of proteins, and PTMomic analysis could expand the identification of cargos in sEVs. At the proteomic level, a high percentage of membrane proteins, especially tetraspanins, was identified. The sEVs-derived phosphoproteome had a remarkably high level of tyrosine-phosphorylated sites. The tyrosine-phosphorylated proteins might be involved with EPH-Ephrin signaling pathway. At the level of N-glycoproteomics, several glycoforms, such as complex N-linked glycans and sialic acids on glycans, were enriched in sEVs. Retrieving of the ligand-receptor interaction in sEVs revealed that extracellular matrix (ECM) and cell adhesion molecule (CAM) represented the most abundant ligand-receptor pairs in sEVs. Mapping the PTM information on the ligands and receptors revealed that N-glycosylation mainly occurred on ECM and CAM proteins, while phosphorylation occurred on different categories of receptors and ligands. A comprehensive PTM map of ECM-receptor interaction and their components is also provided.In summary, we conducted a comprehensive proteomic and PTMomic analysis of sEVs of C2C12 myoblasts. Integrated proteomic, phosphoproteomic, and N-glycoproteomic analysis of sEVs might provide some insights about their specific uptake mechanism.

The effect of macrophages and their exosomes in ischemic heart disease

Ischemic heart disease (IHD) is a leading cause of disability and death worldwide, with immune regulation playing a crucial role in its pathogenesis. Various immune cells are involved, and as one of the key immune cells residing in the heart, macrophages play an indispensable role in the inflammatory and reparative processes during cardiac ischemia. Exosomes, extracellular vesicles containing lipids, nucleic acids, proteins, and other bioactive molecules, have emerged as important mediators in the regulatory functions of macrophages and hold promise as a novel therapeutic target for IHD. This review summarizes the regulatory mechanisms of different subsets of macrophages and their secreted exosomes during cardiac ischemia over the past five years. It also discusses the current status of clinical research utilizing macrophages and their exosomes, as well as strategies to enhance their therapeutic efficacy through biotechnology. The aim is to provide valuable insights for the treatment of IHD.

Extracellular Microvesicles Modified with Arginine-Rich Peptides for Active Macropinocytosis Induction and Delivery of Therapeutic Molecules

Extracellular vesicles (EVs), including exosomes and microvesicles (MVs), transfer bioactive molecules from donor to recipient cells in various pathophysiological settings, thereby mediating intercellular communication. Despite their significant roles in extracellular signaling, the cellular uptake mechanisms of different EV subpopulations remain unknown. In particular, plasma membrane-derived MVs are larger vesicles (100 nm to 1 μm in diameter) and may serve as efficient molecular delivery systems due to their large capacity; however, because of size limitations, receptor-mediated endocytosis is considered an inefficient means for cellular MV uptake. This study demonstrated that macropinocytosis (lamellipodia formation and plasma membrane ruffling, causing the engulfment of large fluid volumes outside cells) can enhance cellular MV uptake. We developed experimental techniques to induce macropinocytosis-mediated MV uptake by modifying MV membranes with arginine-rich cell-penetrating peptides for the intracellular delivery of therapeutic molecules.

The impact of hUC MSC-derived exosome-nanoliposome hybrids on α-synuclein fibrillation and neurotoxicity

Amyloid aggregation of α-synuclein (αSN) protein amplifies the pathogenesis of neurodegenerative diseases (NDs) such as Parkinson's disease (PD). Consequently, blocking aggregation or redirecting self-assembly to less toxic aggregates could be therapeutic. Here, we improve brain-specific nanocarriers using a hybrid of exosomes (Ex) from human umbilical cord mesenchymal stem cells (hUC MSCs) and nanoliposomes containing baicalein (Ex-NLP-Ba) and oleuropein (Ex-NLP-Ole). The hybrids contained both lipid membranes, Ex proteins, and baicalein or oleuropein. Fluorescence resonance energy transfer analysis confirmed their proper integration. The hybrids reduced the extent of αSN fibrillation and interfered with secondary nucleation and disaggregation. They not only reduced αSN pathogenicity but also enhanced drug internalization into cells, surpassing the efficacy of NLP alone, and also crossed the blood-brain barrier in a cellular model. We conclude that Ex can be successfully extracted and efficiently merged with NLPs while retaining its original properties, demonstrating great potential as a theranostic drug delivery vehicle against NDs like PD.

Methods, Mechanisms, and Application Prospects for Enhancing Extracellular Vesicle Uptake

Extracellular vesicles (EVs) are considered to be a new generation of bioinspired nanoscale drug delivery systems due to their low immunogenicity, natural functionality, and excellent biocompatibility. However, limitations such as low uptake efficiency, insufficient production, and inhomogeneous performance undermine their potential. To address these issues, numerous researchers have put forward various methods and applications for enhancing EV uptake in recent decades. In this review, we introduce various methods for the cellular uptake of EVs and summarize recent advances on the methods and mechanisms for enhancing EV uptake. In addition, we provide further understanding regarding enhancing EV uptake and put forward prospects and challenges for the development of EV-based therapy in the future.

Small extracellular vesicles loaded with carboplatin effectively enhance the cytotoxicity of drug-resistant cells from Y79 cells-in vitro

Drug resistance (DR) is one of the challenges in treating retinoblastoma (Rb) that warrants novel approaches. With the emerging evidence on the role of small extracellular vesicles (sEVs) as a drug-delivery carrier system, in this study, we derived the drug-resistant (DR) clones of Y79 cells and evaluated the efficacy of sEVs-loaded with carboplatin (sEVs-CPT) to reverse the chemoresistance. Drug-resistant clones of Y79 cells (DR-Y79) were systematically developed through sequential exposure to carboplatin (CPT), showcasing a sixfold increase in inhibitory concentration when compared to parental Y79 cells (IC50: 41.4 µg/mL and 6.2 µg/mL) (P<0.0001). These DR-Y79 cells show higher expression of ABCG2 and higher expression of DR genes than parental Y79 cells (P<0.0001). The sEVs were isolated from the conditioned media of Y79 cells using ultracentrifugation (UC) and characterized. Further, the sEVs were loaded with CPT and achieved higher encapsulation efficiency at one hour, and drug release of sEVs-CPT was highest at ∼80% at pH 5.0. The cytotoxicity of sEVs-CPT on Y79 cells and DR-Y79 was higher when compared to the CPT (IC50: 3.5 µg/mL vs 6.2 µg/mL; 23.1 µg/mL vs 41.2 µg/mL) (p<0.0001). This study demonstrates that sequential exposure to CPT generates DR clones of Y79 cells, which could serve as an appropriate model to evaluate the efficacy of drugs. The sEVs-CPT were highly effective in enhancing cytotoxicity in DR-Y79 cells, and appear to hold promise as a novel complimentary drug delivery system.

Dissemination of the Flavivirus Subgenomic Replicon Genome and Viral Proteins by Extracellular Vesicles

Extracellular vesicles (EVs) such as exosomes have been shown to play physiological roles in cell-to-cell communication by delivering various proteins and nucleic acids. In addition, several studies revealed that the EVs derived from the cells that are infected with certain viruses could transfer the full-length viral genomes, resulting in EVs-mediated virus propagation. However, the possibility cannot be excluded that the prepared EVs were contaminated with infectious viral particles. In this study, the cells that harbor subgenomic replicon derived from the Japanese encephalitis virus and dengue virus without producing any replication-competent viruses were employed as the EV donor. It was demonstrated that the EVs in the culture supernatants of those cells were able to transfer the replicon genome to other cells of various types. It was also shown that the EVs were incorporated by the recipient cells primarily through macropinocytosis after interaction with CD33 and Tim-1/Tim-4 on HeLa and K562 cells, respectively. Since the methods used in this study are free from contamination with infectious viral particles, it is unequivocally indicated that the flavivirus genome can be transferred by EVs from cell to cell, suggesting that this pathway, in addition to the classical receptor-mediated infection, may play some roles in the viral propagation and pathogenesis.

Exosome-Mediated Antigen Delivery: Unveiling Novel Strategies in Viral Infection Control and Vaccine Design

Exosomes are small subtypes of extracellular vesicles (EVs) naturally released by different types of cells into their environment. Their physiological roles appear to be multiple, yet many aspects of their biological activities remain to be understood. These vesicles can transport and deliver a variety of cargoes and may serve as unconventional secretory vesicles. Thus, they play a crucial role as important vectors for intercellular communication and the maintenance of homeostasis. Exosome production and content can vary under several stresses or modifications in the cell microenvironment, influencing cellular responses and stimulating immunity. During infectious processes, exosomes are described as double-edged swords, displaying both beneficial and detrimental effects. Owing to their tractability, the analysis of EVs from multiple biofluids has become a booming tool for monitoring various pathologies, from infectious to cancerous origins. In this review, we present an overview of exosome features and discuss their particular and ambiguous functions in infectious contexts. We then focus on their properties as diagnostic or therapeutic tools. In this regard, we explore the capacity of exosomes to vectorize immunogenic viral antigens and their function in mounting adaptive immune responses. As exosomes provide interesting platforms for antigen presentation, we further review the available data on exosome engineering, which enables peptides of interest to be exposed at their surface. In the light of all these data, exosomes are emerging as promising avenues for vaccine strategies.

Size-exclusion chromatography combined with DIA-MS enables deep proteome profiling of extracellular vesicles from melanoma plasma and serum

Extracellular vesicles (EVs) are important players in melanoma progression, but their use as clinical biomarkers has been limited by the difficulty of profiling blood-derived EV proteins with high depth of coverage, the requirement for large input amounts, and complex protocols. Here, we provide a streamlined and reproducible experimental workflow to identify plasma- and serum- derived EV proteins of healthy donors and melanoma patients using minimal amounts of sample input. SEC-DIA-MS couples size-exclusion chromatography to EV concentration and deep-proteomic profiling using data-independent acquisition. From as little as 200 µL of plasma per patient in a cohort of three healthy donors and six melanoma patients, we identified and quantified 2896 EV-associated proteins, achieving a 3.5-fold increase in depth compared to previously published melanoma studies. To compare the EV-proteome to unenriched blood, we employed an automated workflow to deplete the 14 most abundant proteins from plasma and serum and thereby approximately doubled protein group identifications versus native blood. The EV proteome diverged from corresponding unenriched plasma and serum, and unlike the latter, separated healthy donor and melanoma patient samples. Furthermore, known melanoma markers, such as MCAM, TNC, and TGFBI, were upregulated in melanoma EVs but not in depleted melanoma plasma, highlighting the specific information contained in EVs. Overall, EVs were significantly enriched in intact membrane proteins and proteins related to SNARE protein interactions and T-cell biology. Taken together, we demonstrated the increased sensitivity of an EV-based proteomic workflow that can be easily applied to larger melanoma cohorts and other indications.

Brassica oleracea L. var. italica Aquaporin Reconstituted Proteoliposomes as Nanosystems for Resveratrol Encapsulation

Aquaporins (AQPs), membrane proteins responsible for facilitating water transport, found in plant membrane vesicles (MV), have been related to the functionality and stability of MV. We focused on AQPs obtained from broccoli, as they show potential for biotechnological applications. To gain further insight into the role of AQPs in MV, we describe the heterologous overexpression of two broccoli AQPs (BoPIP1;2 and BoPIP2;2) in Pichia pastoris, resulting in their purification with high yield (0.14 and 0.99 mg per gram cells for BoPIP1;2 and BoPIP2;2). We reconstituted AQPs in liposomes to study their functionality, and the size of proteoliposomes did not change concerning liposomes. BoPIP2;2 facilitated water transport, which was preserved for seven days at 4 °C and at room temperature but not at 37 °C. BoPIP2;2 was incorporated into liposomes to encapsulate a resveratrol extract, resulting in increased entrapment efficiency (EE) compared to conventional liposomes. Molecular docking was utilized to identify binding sites in PIP2s for resveratrol, highlighting the role of aquaporins in the improved EE. Moreover, interactions between plant AQP and human integrin were shown, which may increase internalization by the human target cells. Our results suggest AQP-based alternative encapsulation systems can be used in specifically targeted biotechnological applications.

Extracellular Vesicles in the Skin Microenvironment: Emerging Roles as Biomarkers and Therapeutic Tools in Dermatologic Health and Disease

The recent discovery of extracellular vesicles (EVs) carrying cargo consisting of various bioactive macromolecules that can modulate the phenotype of recipient target cells has revealed an important new mechanism through which cells can signal their neighbors and regulate their microenvironment. Because EV cargo and composition correlate with the physiologic state of their cell of origin, investigations into the role of EVs in disease pathogenesis and progression have become an area of intense study. The physiologic and pathologic effects of EVs on their microenvironment are incredibly diverse and include the modulation of molecular pathways involved in angiogenesis, inflammation, wound healing, epithelial-mesenchymal transition, proliferation, and immune escape. This review examines recent studies on the role of EVs in diseases of the skin and on how differences in EV composition and cargo can alter cell states and the surrounding microenvironment. We also discuss the potential clinical applications of EVs in skin disease diagnosis and management. We examine their value as an easily isolated source of biomarkers to predict disease prognosis or to monitor patient response to treatment. Given the ability of EVs to modulate disease-specific signaling pathways, we also assess their potential to serve as novel personalized precision therapeutic tools for dermatological diseases.

A Novel Cargo Delivery System-AnCar-ExoLaIMTS Ameliorates Arthritis via Specifically Targeting Pro-Inflammatory Macrophages

Macrophages are heterogenic phagocytic cells that play distinct roles in physiological and pathological processes. Targeting different types of macrophages has shown potent therapeutic effects in many diseases. Although many approaches are developed to target anti-inflammatory macrophages, there are few researches on targeting pro-inflammatory macrophages, which is partially attributed to their non-s pecificity phagocytosis of extracellular substances. In this study, a novel recombinant protein is constructed that can be anchored on an exosome membrane with the purpose of targeting pro-inflammatory macrophages via antigen recognition, which is named AnCar-ExoLaIMTS . The data indicate that the phagocytosis efficiencies of pro-inflammatory macrophages for different AnCar-ExoLaIMTS show obvious differences. The AnCar-ExoLaIMTS3 has the best targeting ability for pro-inflammatory macrophages in vitro and in vivo. Mechanically, AnCar-ExoLaIMTS3 can specifically recognize the leucine-rich repeat domain of the TLR4 receptor, and then enter into pro-inflammatory macrophages via the TLR4-mediated receptor endocytosis pathway. Moreover, AnCar-ExoLaIMTS3 can efficiently deliver therapeutic cargo to pro-inflammatory macrophages and inhibit the synovial inflammatory response via downregulation of HIF-1α level, thus ameliorating the severity of arthritis in vivo. Collectively, the work established a novel gene/drug delivery system that can specifically target pro-inflammatory macrophages, which may be beneficial for the treatments of arthritis and other inflammatory diseases.

Navigating the brain: the role of exosomal shuttles in precision therapeutics

Brain diseases have become one of the leading roots of mortality and disability worldwide, contributing a significant part of the disease burden on healthcare systems. The blood-brain barrier (BBB) is a primary physical and biological obstacle that allows only small molecules to pass through it. Its selective permeability is a significant challenge in delivering therapeutics into the brain for treating brain dysfunction. It is estimated that only 2% of the new central nervous system (CNS) therapeutic compounds can cross the BBB and achieve their therapeutic targets. Scientists are exploring various approaches to develop effective cargo delivery vehicles to promote better therapeutics targeting the brain with minimal off-target side effects. Despite different synthetic carriers, one of the natural brain cargo delivery systems, "exosomes," are now employed to transport drugs through the BBB. Exosomes are naturally occurring small extracellular vesicles (EVs) with unique advantages as a therapeutic delivery system for treating brain disorders. They have beneficial innate aspects of biocompatibility, higher stability, ability to cross BBB, low cytotoxicity, low immunogenicity, homing potential, targeted delivery, and reducing off-site target effects. In this review, we will discuss the limitations of synthetic carriers and the utilization of naturally occurring exosomes as brain-targeted cargo delivery vehicles and highlight the methods for modifying exosome surfaces and drug loading into exosomes. We will also enlist neurodegenerative disorders targeted with genetically modified exosomes for their treatment.

Entry and exit of extracellular vesicles to and from the blood circulation

Extracellular vesicles (EVs) are biological nanoparticles that promote intercellular communication by delivering bioactive cargo over short and long distances. Short-distance communication takes place in the interstitium, whereas long-distance communication is thought to require transport through the blood circulation to reach distal sites. Extracellular vesicle therapeutics are frequently injected systemically, and diagnostic approaches often rely on the detection of organ-derived EVs in the blood. However, the mechanisms by which EVs enter and exit the circulation are poorly understood. Here, the lymphatic system and transport across the endothelial barrier through paracellular and transcellular routes are discussed as potential pathways for EV entry to and exit from the blood circulatory system.

Dacarbazine-primed carbon quantum dots coated with breast cancer cell-derived exosomes for improved breast cancer therapy

Imprecise targeting of chemotherapeutic drugs often leads to severe toxicity during breast cancer therapy. To address this issue, we have devised a strategy to load dacarbazine (DC) into fucose-based carbon quantum dots (CQDs), which are subsequently coated with exosomes (Ex-DC@CQDs) derived from breast cancer cells. Nanoparticle tracking analysis and western blotting revealed that Ex-DC@CQDs retained the structural and functional characteristics of exosomes. We found that exosomes facilitated the transport of DC@CQDs to cancer cells via heparan sulfate proteoglycan (HSPG) receptors, followed by an augmented depolarization of the mitochondrial membrane potential, ROS generation, and induction of apoptosis leading to cell death. In vivo imaging and pharmacokinetic studies demonstrated enhanced antitumor targeting and efficacy compared to free DC which we attribute to an improved pharmacokinetic profile, a greater tumor accumulation via exosome-mediated- HSPG receptor-driven cell uptake, and sustained release of the Ex-DC@CQDs. Our findings may pave the way for the further development of biologically sourced nanocarriers for breast cancer targeting.

Cellular Uptake of Engineered Extracellular Vesicles: Biomechanisms, Engineered Strategies, and Disease Treatment

Extracellular vesicles (EVs), lipid-enclosed nanosized membrane vesicles, are regarded as new vehicles and therapeutic agents in intercellular communication. During internal circulation, if EVs are not effectively taken up by recipient cells, they will be cleared as "cellular waste" and unable to deliver therapeutic components. It can be seen that cells uptake EVs are the prerequisite premise for sharing intercellular biological information. However, natural EVs have a low rate of absorption by their recipient cells, off-target delivery, and rapid clearance from circulation, which seriously reduces the utilization rate. Affecting the uptake rate of EVs through engineering technologies is essential for therapeutic applications. Engineering strategies for customizing EV uptake can potentially overcome these limitations and enable desirable therapeutic uses of EVs. In this review, the mechanism and influencing factors of natural EV uptake will be described in detail. Targeting each EV uptake mechanism, the strategies of engineered EVs and their application in diseases will be emphatically discussed. Finally, the future challenges and perspectives of engineered EVs are presented multidimensionally.

M2 exosomes modified by hydrogen sulfide promoted bone regeneration by moesin mediated endocytosis

Bone defects caused by trauma or tumor led to high medical costs and poor life quality for patients. The exosomes, micro vesicles of 30-150 nm in diameter, derived from macrophages manipulated bone regeneration. However, the role of hydrogen sulfide (H2S) in the biogenesis and function of exosomes and its effects on bone regeneration remains elusive. In this study, we used H2S slow releasing donor GYY4137 to stimulate macrophages and found that H2S promoted the polarization of M2 macrophages to increase bone regeneration of MSCs in vitro and in vivo. Moreover, we developed the H2S pre-treated M2 macrophage exosomes and found these exosomes displayed significantly higher capacity to promote bone regeneration in calvarial bone defects by re-establishing the local immune microenvironment. Mechanically, H2S treatment altered the protein profile of exosomes derived from M2 macrophages. One of the significantly enriched exosomal proteins stimulated by H2S, moesin protein, facilitated the exosomes endocytosis into MSCs, leading to activated the β-catenin signaling pathway to promote osteogenic differentiation of MSCs. In summary, H2S pretreated M2 exosomes promoted the bone regeneration of MSCs via facilitating exosomes uptake by MSCs and activate β-catenin signaling pathway. This study not only provides new strategies for promoting bone regeneration, but also provides new insights for the effect and mechanism of exosomes internalization.

The Current Status and Future Direction of Extracellular Nano-vesicles in the Alleviation of Skin Disorders

Exosomes are extracellular vesicles (EVs) that originate from endocytic membranes. The transfer of biomolecules and biological compounds such as enzymes, proteins, RNA, lipids, and cellular waste disposal through exosomes plays an essential function in cell-cell communication and regulation of pathological and physiological processes in skin disease. The skin is one of the vital organs that makes up about 8% of the total body mass. This organ consists of three layers, epidermis, dermis, and hypodermis that cover the outer surface of the body. Heterogeneity and endogeneity of exosomes is an advantage that distinguishes them from nanoparticles and liposomes and leads to their widespread usage in the remedy of dermal diseases. The biocompatible nature of these extracellular vesicles has attracted the attention of many health researchers. In this review article, we will first discuss the biogenesis of exosomes, their contents, separation methods, and the advantages and disadvantages of exosomes. Then we will highlight recent developments related to the therapeutic applications of exosomes in the treatment of common skin disorders like atopic dermatitis, alopecia, epidermolysis bullosa, keloid, melanoma, psoriasis, and systemic sclerosis.

Unveiling the Complex World of Extracellular Vesicles: Novel Characterization Techniques and Manufacturing Considerations

Extracellular vesicles (EVs) function as potent mediators of intercellular communication for many in vivo processes, contributing to both health and disease related conditions. Given their biological origins and diverse functionality from correspondingly unique "cargo" compositions, both endogenous and modified EVs are garnering attention as promising therapeutic modalities and vehicles for targeted therapeutic delivery applications. Their diversity in composition, however, has revealed a significant need for more comprehensive analytical-based characterization methods, and manufacturing processes that are consistent and scalable. In this review, we explore the dynamic landscape of EV research and development efforts, ranging from novel isolation approaches, to their analytical assessment through novel characterization techniques, and to their production by industrial-scale manufacturing process considerations. Expanding the horizon of these topics to EVs for in-human applications, we underscore the need for stringent development and adherence to Good Manufacturing Practice (GMP) guidelines. Wherein, the intricate interplay of raw materials, production in bioreactors, and isolation practices, along with analytical assessments compliant with the Minimal Information for Studies of Extracellular Vesicles (MISEV) guidelines, in conjunction with reference standard materials, collectively pave the way for standardized and consistent GMP production processes.

Unraveling the Multifaceted Roles of Extracellular Vesicles: Insights into Biology, Pharmacology, and Pharmaceutical Applications for Drug Delivery

Extracellular vesicles (EVs) are nanoparticles released from various cell types that have emerged as powerful new therapeutic option for a variety of diseases. EVs are involved in the transmission of biological signals between cells and in the regulation of a variety of biological processes, highlighting them as potential novel targets/platforms for therapeutics intervention and/or delivery. Therefore, it is necessary to investigate new aspects of EVs' biogenesis, biodistribution, metabolism, and excretion as well as safety/compatibility of both unmodified and engineered EVs upon administration in different pharmaceutical dosage forms and delivery systems. In this review, we summarize the current knowledge of essential physiological and pathological roles of EVs in different organs and organ systems. We provide an overview regarding application of EVs as therapeutic targets, therapeutics, and drug delivery platforms. We also explore various approaches implemented over the years to improve the dosage of specific EV products for different administration routes.

Heterogeneity and Compositional Diversities of Campylobacter jejuni Outer Membrane Vesicles (OMVs) Drive Multiple Cellular Uptake Processes

Naturally secreted outer membrane vesicles (OMVs) from gut microbes carry diverse cargo, including proteins, nucleic acids, toxins, and many unidentified secretory factors. Bacterial OMVs can shuttle molecules across different cell types as a generalized secretion system, facilitating bacterial pathogenicity and self-survival. Numerous mucosal pathogens, including Campylobacter jejuni (C. jejuni), share a mechanism of harmonized secretion of major virulence factors. Intriguingly, as a common gut pathogen, C. jejuni lacks some classical virulence-associated secretion systems; alternatively, it often employs nanosized lipid-bound OMVs as an intensive strategy to deliver toxins, including secretory proteins, into the target cells. To better understand how the biophysical and compositional attributes of natural OMVs of C. jejuni regulate their cellular interactions to induce a biologically relevant host response, we conducted an in-depth morphological and compositional analysis of naturally secreted OMVs of C. jejuni. Next, we focused on understanding the mechanism of host cell-specific OMVs uptake from the extracellular milieu. We showed that intracellular perfusion of OMVs is mediated by cytosolic as well as multiple endocytic uptake processes due to the heterogenic nature, abundance of surface proteins, and membrane phospholipids acquired from the source bacteria. Furthermore, we used human and avian cells as two different host targets to provide evidence of target cell-specific preferential uptake of OMVs. Together, the present study provides insight into the unique functionality of natural OMVs of C. jejuni at the cellular interface, upholding their potential for multimodal use as prophylactic and therapeutic carriers.

Dairy Intake Modifies the Level of the Bile Acid Precursor and Its Correlation with Serum Proteins Associated with Cholesterol Clearance in Subjects with Hyperinsulinemia

Bile acids regulate glucose homeostasis and lipid metabolism. Further, the levels of bile acids can be influenced by the intake of dairy products. Although the serum proteome can provide information on the biological pathways associated with different metabolites, it is unknown whether the intake of dairy modifies such associations between bile acids and the proteome. The objectives of this study were to examine plasma bile acid profiles, find the correlations between bile acids and lipid as well as glycemic markers, and to uncover the correlation between bile acids and proteins after high dairy (HD) and adequate dairy (AD) intake among 25 overweight individuals with hyperinsulinemia. In this randomized crossover-trial study, hyperinsulinemia adults were randomized to both HD (≥4 servings/day) and AD (≤2 servings/day) for 6 weeks. Measurements and analyses were performed on before- as well as after- AD and HD conditions. The results indicated that plasma 7α-hydroxy-4-cholesten-3-one (7AC4) increased after HD in comparison with before HD intake (p = 0.03). After adjusting for BMI, age, and sex, 7AC4 positively correlated with triglyceride levels in the pre-AD (r = 0.44; p = 0.03) and post-HD (r = 0.42; p = 0.04). Further, 7AC4 correlated positively with proteins associated with high-density lipoprotein particle remodeling pathway and reverse cholesterol transport only after HD consumption. Thus, the consumption of higher dairy intake modifies the association between 7AC4-a biomarker for bile acid synthesis-and serum proteins involved in cholesterol clearance. Overall, higher dairy consumption may have a positive effect on cholesterol metabolism in subjects at risk of type 2 diabetes.

Colorectal cancer cell exosome and cytoplasmic membrane for homotypic delivery of therapeutic molecules

Colorectal cancer (CRC) is one of the most common causes of death in the world. The multi-drug resistance, especially in metastatic colorectal cancer, drives the development of new strategies that secure a positive outcome and reduce undesirable side effects. Nanotechnology has made an impact in addressing some pharmacokinetic and safety issues related to administration of free therapeutic agents. However, demands of managing complex biointerfacing require equally complex methods for introducing stimuli-responsive or targeting elements. In order to procure a more efficient solution to the overcoming of biological barriers, the physiological functions of cancer cell plasma and exosomal membranes provided the source of highly functionalized coatings. Biomimetic nanovehicles based on colorectal cancer (CRC) membranes imparted enhanced biological compatibility, immune escape and protection to diverse classes of therapeutic molecules. When loaded with therapeutic load or used as a coating for other therapeutic nanovehicles, they provide highly efficient and selective cell targeting and uptake. This review presents a detailed overview of the recent application of homotypic biomimetic nanovehicles in the management of CRC. We also address some of the current possibilities and challenges associated with the CRC membrane biomimetics.

Challenges and future scope of exosomes in the treatment of cardiovascular diseases

Exosomes are nanosized vesicles that carry biologically diverse molecules for intercellular communication. Researchers have been trying to engineer exosomes for therapeutic purposes by using different approaches to deliver biologically active molecules to the various target cells efficiently. Recent technological advances may allow the biodistribution and pharmacokinetics of exosomes to be modified to meet scientific needs with respect to specific diseases. However, it is essential to determine an exosome's optimal dosage and potential side effects before its clinical use. Significant breakthroughs have been made in recent decades concerning exosome labelling and imaging techniques. These tools provide in situ monitoring of exosome biodistribution and pharmacokinetics and pinpoint targetability. However, because exosomes are nanometres in size and vary significantly in contents, a deeper understanding is required to ensure accurate monitoring before they can be applied in clinical settings. Different research groups have established different approaches to elucidate the roles of exosomes and visualize their spatial properties. This review covers current and emerging strategies for in vivo and in vitro exosome imaging and tracking for potential studies.

Differences and Similarities of the Intravenously Administered Lipid Nanoparticles in Three Clinical Trials: Potential Linkage between Lipid Nanoparticles and Extracellular Vesicles

Lipid nanoparticles (LNPs) are clinically validated drug-delivery carriers. However, clinical data on intravenously administered LNPs are limited compared with those on intramuscularly administered LNPs (mRNA vaccines against COVID-19). Here, we reviewed three clinically tested intravenously administered LNPs (patisiran, mRNA-1944, and NTLA-2001). We summarize the differences and similarities in their formulations, mechanisms of action, and pharmacokinetics profiles. In humans, patisiran and mRNA-1944 exhibited similar multiphasic pharmacokinetic profiles with a secondary peak in the RNA concentration. siRNA (patisiran) and mRNA (mRNA-1944) exhibited prolonged blood circulation and were detectable for more than 28 days after a single administration. We further summarize the basics of extracellular vesicles (EVs) and discuss the potential linkages between LNPs and EVs. This Review provides an understanding of the human clinical data of intravenous LNP formulations, which can be potentially explored to develop next-generation LNP-and EV-based drug delivery carriers.

A Comparison of Cellular Uptake Mechanisms, Delivery Efficacy, and Intracellular Fate between Liposomes and Extracellular Vesicles

A key aspect for successful drug delivery via lipid-based nanoparticles is their internalization in target cells. Two prominent examples of such drug delivery systems are artificial phospholipid-based carriers, such as liposomes, and their biological counterparts, the extracellular vesicles (EVs). Despite a wealth of literature, it remains unclear which mechanisms precisely orchestrate nanoparticle-mediated cargo delivery to recipient cells and the subsequent intracellular fate of therapeutic cargo. In this review, internalization mechanisms involved in the uptake of liposomes and EVs by recipient cells are evaluated, also exploring their intracellular fate after intracellular trafficking. Opportunities are highlighted to tweak these internalization mechanisms and intracellular fates to enhance the therapeutic efficacy of these drug delivery systems. Overall, literature to date shows that both liposomes and EVs are predominantly internalized through classical endocytosis mechanisms, sharing a common fate: accumulation inside lysosomes. Studies tackling the differences between liposomes and EVs, with respect to cellular uptake, intracellular delivery and therapy efficacy, remain scarce, despite its importance for the selection of an appropriate drug delivery system. In addition, further exploration of functionalization strategies of both liposomes and EVs represents an important avenue to pursue in order to control internalization and fate, thereby improving therapeutic efficacy.

Targeted therapy using engineered extracellular vesicles: principles and strategies for membrane modification

Extracellular vesicles (EVs) are 30-150 nm membrane-bound vesicles naturally secreted by cells and play important roles in intercellular communication by delivering regulatory molecules such as proteins, lipids, nucleic acids and metabolites to recipient cells. As natural nano-carriers, EVs possess desirable properties such as high biocompatibility, biological barrier permeability, low toxicity, and low immunogenicity, making them potential therapeutic delivery vehicles. EVs derived from specific cells have inherent targeting capacity towards specific cell types, which is yet not satisfactory enough for targeted therapy development and needs to be improved. Surface modifications endow EVs with targeting abilities, significantly improving their therapeutic efficiency. Herein, we first briefly introduce the biogenesis, composition, uptake and function of EVs, and review the cargo loading approaches for EVs. Then, we summarize the recent advances in surface engineering strategies of EVs, focusing on the applications of engineered EVs for targeted therapy. Altogether, EVs hold great promise for targeted delivery of various cargos, and targeted modifications show promising effects on multiple diseases.