Exosome-based delivery of super-repressor IκBα relieves sepsis-associated organ damage and mortality

Extracellular Vesicles in Renal Inflammatory Diseases: Revealing Mechanisms of Extracellular Vesicle-Mediated Macrophage Regulation

Renal inflammatory diseases are a group of severe conditions marked by significant morbidity and mortality. Extracellular vesicles (EVs), as facilitators of intercellular communication, have been recognized as pivotal regulators of renal inflammatory diseases, significantly contributing to these conditions by modulating immune responses among other mechanisms. This review highlights the intricate mechanisms through which EVs modulate macrophage-kidney cell interactions by regulating macrophages, the principal immune cells within the renal milieu. This regulation subsequently influences the pathophysiology of renal inflammatory diseases such as acute kidney injury and chronic kidney disease. Furthermore, understanding these mechanisms offers novel opportunities to alleviate the severe consequences associated with renal inflammatory diseases. In addition, we summarize the therapeutic landscape based on EV-mediated macrophage regulatory mechanisms, highlighting the potential of EVs as biomarkers and therapeutic targets as well as the challenges and limitations of translating therapies into clinical practice.

Effects and Mechanisms of Extracellular Vesicles in Different Models of Acute Kidney Injury

Acute kidney injury (AKI) is a rapid decline in renal function caused by ischemia/reperfusion (I/R), renal toxic injury, and sepsis. While the precise molecular mechanisms underlying AKI are still under investigation, current therapeutic approaches remain insufficient. In recent years, there has been growing evidence that mesenchymal stem cells (MSCs) have great potential in accelerating renal repair after AKI in various preclinical models, while there has been extensive research on extracellular vesicles (EVs) as therapeutic mediators in AKI models, and they are considered to be superior to MSCs as new regenerative therapies. EVs are nanoparticles secreted by various types of cells under physiological and pathological conditions. EVs derived from various sources possess biomarker potential and play crucial roles in mediating cellular communication between kidney cells and other tissue cells by transmitting signal molecules. These vesicles play a direct and indirect role in regulating the pathophysiological mechanisms of AKI and contribute to the occurrence, development, treatment, and repair of AKI. In this review, we briefly outline the essential characteristics of EVs, focus on the multiple molecular mechanisms currently involved in the protection of EVs against different types of AKI, and further discuss the potential targets of EVs from different sources in the treatment of AKI. Finally, we summarized the deficiencies in the production and treatment of EVs and the current strategies for improvement.

Clinical Impact of Exosome Chemistry in Cancer

As we progress into the 21st century, cancer stands as one of the most dreaded diseases. With approximately one in every four individuals facing a lifetime risk of developing cancer, cancer remains one of the most serious health challenges worldwide. Its multifaceted nature makes it an arduous and tricky problem to diagnose and treat. Over the years, researchers have explored plenty of approaches and avenues to improve cancer management. One notable strategy includes the study of extracellular vesicles (EVs) as potential biomarkers and therapeutics. Among these EVs, exosomes have emerged as particularly promising candidates due to their unique characteristic properties and functions. They are small membrane-bound vesicles secreted by cells carrying a cargo of biomolecules such as proteins, nucleic acids, and lipids. These vesicles play crucial roles in intercellular communication, facilitating the transfer of biological information between cell-to-cell communication. Exosomes transport cargoes such as DNA, RNA, proteins, and lipids involved in cellular reprogramming and promoting cancer. In this review, we explore the molecular composition of exosomes, significance of exosomes chemistry in cancer development, and its theranostic application as well as exosomes research complications and solutions.

FGF21 ameliorates septic liver injury by restraining proinflammatory macrophages activation through the autophagy/HIF-1α axis

INTRODUCTION

Sepsis, a systemic immune syndrome caused by severe trauma or infection, poses a substantial threat to the health of patients worldwide. The progression of sepsis is heavily influenced by septic liver injury, which is triggered by infection and cytokine storms, and has a significant impact on the tolerance and prognosis of septic patients. The objective of our study is to elucidate the biological role and molecular mechanism of fibroblast growth factor 21 (FGF21) in the process of sepsis.

OBJECTIVES

This study was undertaken in an attempt to elucidate the function and molecular mechanism of FGF21 in therapy of sepsis.

METHODS

Serum concentrations of FGF21 were measured in sepsis patients and septic mice. Liver injury was compared between mice FGF21 knockout (KO) mice and wildtype (WT) mice. To assess the therapeutic potential, recombinant human FGF21 was administered to septic mice. Furthermore, the molecular mechanism of FGF21 was investigated in mice with myeloid-cell specific HIF-1α overexpression mice (LyzM-CreDIO-HIF-1α) and myeloid-cell specific Atg7 knockout mice (Atg7△mye).

RESULTS

Serum level of FGF21 was significantly increased in sepsis patients and septic mice. Through the use of recombinant human FGF21 (rhFGF21) and FGF21 KO mice, we found that FGF21 mitigated septic liver injury by inhibiting the initiation and propagation of inflammation. Treatment with rhFGF21 effectively suppressed the activation of proinflammatory macrophages by promoting macroautophagy/autophagy degradation of hypoxia-inducible factor-1α (HIF-1α). Importantly, the therapeutic effect of rhFGF21 against septic liver injury was nullified in LyzM-CreDIO-HIF-1α mice and Atg7△mye mice.

CONCLUSIONS

Our findings demonstrate that FGF21 considerably suppresses inflammation upon septic liver injury through the autophagy/ HIF-1α axis.

The Therapeutic Potential of Exosome Therapy in Sepsis Management: Addressing Complications and Improving Outcomes"

Infection occurs when pathogens penetrate tissues, reproduce, and trigger a host response to both the infectious agents and their toxins. A diverse array of pathogens, including viruses and bacteria, can cause infections. The host's immune system employs several mechanisms to combat these infections, typically involving an innate inflammatory response. Inflammation is a complex biological reaction that can affect various parts of the body and is a key component of the response to harmful stimuli. Sepsis arises when the body's response to infection leads to widespread damage to tissues and organs, potentially resulting in severe outcomes or death. The initial phase of sepsis involves immune system suppression. Early identification and targeted management are crucial for improving sepsis outcomes. Common treatment approaches include antibiotics, intravenous fluids, blood cultures, and monitoring urine output. This study explores the potential of exosome therapy in enhancing the management and alleviation of sepsis symptoms.

Engineered Exosomes Carrying Super-Repressor IκB Reduced Biliary Atresia-Induced Liver Fibrosis in Minipig and Mouse Models

Background and Aim: Biliary atresia is a rare, progressive disease that affects the bile ducts in newborns. Persistent bile duct obstruction induces various pathological conditions, including jaundice, inflammation, and liver fibrosis; however, the exact pathogenesis of biliary atresia is not yet fully understood. Nuclear factor-κB (NF-κB) is widely acknowledged as a key regulator in the pathogenesis of hepatitis and liver fibrosis, and extensive research has been conducted to develop strategies to effectively inhibit its activity to mitigate liver damage. Exosome-based therapeutic platforms offer targeted NF-κB inhibition with low immunogenicity and enhanced liver-specific delivery. This study aimed to evaluate the therapeutic efficacy of Exo-SrIκB in treating cholestatic liver fibrosis using experimental animal models. Methods: Exo-SrIκB (an exosome-based therapy containing the super-repressor IκB protein) using EXPLOR technology (Exosome engineering for Protein Loading via Optically Reversible protein-protein interactions) to encapsulate the super repressor IκB (SrIκB) within exosomes. The therapeutic efficacy of Exo-SrIκB was assessed in minipig and mouse models with experimentally induced cholestatic liver disease. Results: Administration of Exo-SrIκB significantly attenuated liver fibrosis progression in both animal models by inhibiting NF-κB nuclear translocation and reducing the expression of fibrotic markers. Treated animals exhibited reduced collagen deposition, lower α-SMA levels, and improved hepatic function compared to untreated controls. Conclusion: Exo-SrIκB effectively suppressed NF-κB signaling and alleviated liver fibrosis in experimental cholestatic liver disease models, suggesting that exosome-based therapeutics may offer a targeted and biocompatible application to managing liver fibrosis and other chronic liver diseases.

Pathogenic and therapeutic roles of extracellular vesicles in sepsis

Sepsis is a systemic injury resulting in vascular dysfunction, which can lead to multiple organ dysfunction, even shock and death. Extracellular vesicles (EVs) released by mammalian cells and bacteria have been shown to play important roles in intercellular communication and progression of various diseases. In past decades, the functional role of EVs in sepsis and its complications has been well explored. EVs are one of the paracrine components of cells. By delivering bioactive materials, EVs can promote immune responses, particularly the development of inflammation. In addition, EVs can serve as beneficial tools for delivering therapeutic cargos. In this review, we discuss the dual role of EVs in the progression and treatment of sepsis, exploring their intricate involvement in both inflammation and tissue repair processes. Specifically, the remarkable role of engineered strategies based on EVs in the treatment of sepsis is highlighted. The engineering EVs-mediated drug delivery and release strategies offer broad prospects for the effective treatment of sepsis. EVs-based approaches provide a novel avenue for diagnosing sepsis and offer opportunities for more precise intervention.

Exosome-based targeted delivery of NF-κB ameliorates age-related neuroinflammation in the aged mouse brain

Neuroinflammation, a significant contributor to various neurodegenerative diseases, is strongly associated with the aging process; however, to date, no efficacious treatments for neuroinflammation have been developed. In aged mouse brains, the number of infiltrating immune cells increases, and the key transcription factor associated with increased chemokine levels is nuclear factor kappa B (NF-κB). Exosomes are potent therapeutics or drug delivery vehicles for various materials, including proteins and regulatory genes, to target cells. In the present study, we evaluated the therapeutic efficacy of exosomes loaded with a nondegradable form of IκB (Exo-srIκB), which inhibits the nuclear translocation of NF-κB to suppress age-related neuroinflammation. Single-cell RNA sequencing revealed that these anti-inflammatory exosomes targeted macrophages and microglia, reducing the expression of inflammation-related genes. Treatment with Exo-srIκB also suppressed the interactions between macrophages/microglia and T and B cells in the aged brain. We demonstrated that Exo-srIκB successfully alleviates neuroinflammation by primarily targeting activated macrophages and partially modulating the functions of age-related interferon-responsive microglia in the brain. Thus, our findings highlight Exo-srIκB as a potential therapeutic agent for treating age-related neuroinflammation.

Surface modification of extracellular vesicles with polyoxazolines to enhance their plasma stability and tumor accumulation

Extracellular vesicles (EVs) are future promising therapeutics, but their instability in vivo after administration remains an important barrier to their further development. Many groups evaluated EV surface modification strategies to add a targeting group with the aim of controlling EV biodistribution. Conversely, fewer groups focused on their stabilization to obtain "stealth" allogenic EVs. Modulating their stabilization and biodistribution is an essential prerequisite for their development as nano-therapeutics. Here, we explored polyoxazolines with lipid anchors association to the EV membrane (POxylation as an alternative to PEGylation) to stabilize EVs in plasma and control their biodistribution, while preserving their native properties. We found that this modification maintained and seemed to potentiate the immunomodulatory properties of EVs derived from mesenchymal stem/stromal cells (MSC). Using a radiolabeling protocol to track EVs at a therapeutically relevant concentration in vivo, we demonstrated that POxylation is a promising option to stabilize EVs in plasma because it increased EV half-life by 6 fold at 6 h post-injection. Moreover, EV accumulation in tumors was higher after POxylation than after PEGylation.

Extracellular Vesicles as Tools for Crossing the Blood-Brain Barrier to Treat Lysosomal Storage Diseases

Extracellular vesicles (EVs) are nanosized, membrane-bound structures that have emerged as promising tools for drug delivery, especially in the treatment of lysosomal storage disorders (LSDs) with central nervous system (CNS) involvement. This review highlights the unique properties of EVs, such as their biocompatibility, capacity to cross the blood-brain barrier (BBB), and potential for therapeutic cargo loading, including that of enzymes and genetic material. Current therapies for LSDs, like enzyme replacement therapy (ERT), often fail to address neurological symptoms due to their inability to cross the BBB. EVs offer a viable alternative, allowing for targeted delivery to the CNS and improving therapeutic outcomes. We discuss recent advancements in the engineering and modification of EVs to enhance targeting, circulation time and cargo stability, and provide a detailed overview of their application in LSDs, such as Gaucher and Fabry diseases, and Sanfilippo syndrome. Despite their potential, challenges remain in scaling production, ensuring isolation purity, and meeting regulatory requirements. Future developments will focus on overcoming these barriers, paving the way for the clinical translation of EV-based therapies in LSDs and other CNS disorders.

Nature's carriers: leveraging extracellular vesicles for targeted drug delivery

With the rapid development of drug delivery systems, extracellular vesicles (EVs) have emerged as promising stars for improving targeting abilities and realizing effective delivery. Numerous studies have shown when compared to conventional strategies in targeted drug delivery (TDD), EVs-based strategies have several distinguished advantages besides targeting, such as participating in cell-to-cell communications and immune response, showing high biocompatibility and stability, penetrating through biological barriers, etc. In this review, we mainly focus on the mass production of EVs including the challenges and strategies for scaling up EVs production in a cost-effective and reproducible manner, the loading and active targeting methods, and examples of EVs as vehicles for TDD in consideration of potential safety and regulatory issues associated. We also conclude and discuss the rigor and reproducibility of EVs production, the current research status of the application of EVs-based strategies to targeted drug delivery, clinical conversion prospects, and existing chances and challenges.

Nanolevel Immunomodulators in Sepsis: Novel Roles, Current Perspectives, and Future Directions

Sepsis represents a profound challenge in critical care, characterized by a severe systemic inflammatory response which can lead to multi-organ failure and death. The intricate pathophysiology of sepsis involves an overwhelming immune reaction that disrupts normal host defense mechanisms, necessitating innovative approaches to modulation. Nanoscale immunomodulators, with their precision targeting and controlled release capabilities, have emerged as a potent solution to recalibrate immune responses in sepsis. This review explores the recent advancements in nanotechnology for sepsis management, emphasizing the integration of nanoparticulate systems to modulate immune function and inflammatory pathways. Discussions detail the development of the immune system, the distinct inflammatory responses triggered by sepsis, and the scientific principles underpinning nanoscale immunomodulation, including specific targeting mechanisms and delivery systems. The review highlights nanoformulation designs aimed at enhancing bioavailability, stability, and therapeutic efficacy, which shows promise in clinical settings by modulating key inflammatory pathways. Ultimately, this review synthesizes the current state of knowledge and projects future directions for research, underscoring the transformative potential of nanolevel immunomodulators for sepsis treatment through innovative technologies and therapeutic strategies.

Innate immunity-modulating nanobiomaterials for controlling inflammation resolution

The acute inflammatory response is an inherent protective mechanism, its unsuccessful resolution can contribute to disease pathogenesis and potentially lead to death. Innate immune cells are the first line of host defenders and play a substantial role in inflammation initiation, amplification, resolution, or subsequent disease progression. As the resolution of inflammation is an active and highly regulated process, modulating innate immune cells, including neutrophils, monocytes and macrophages, and endothelial cells, and their interactions offer opportunities to control excessive inflammation. Nanobiomaterials have shown superior therapeutic potential in inflammation-related diseases by manipulating inflammatory responses because nanobiomaterials can target and interact with innate immune cells. Versatile nanobiomaterials can be designed for targeted modulation of specific innate immune responses. Nanopro-resolving medicines have been prepared both with pro-resolving lipid mediators and peptides each demonstrated to active resolution of inflammation in animal disease models. Here, we review innovative nanobiomaterials for modulating innate immunity and alleviating inflammation. We summarise the strategies converging the design of nanobiomaterials and the nano-bio interaction in modulating innate immune profiles and propelling the advancement of nanobiomaterials for inflammatory disease treatments. We also propose the future perspectives and translational challenges of nanobiomaterials that need to be overcome in this swiftly rising field.

Engineered extracellular vesicles enable high-efficient delivery of intracellular therapeutic proteins

Developing an intracellular delivery system is of key importance in the expansion of protein-based therapeutics acting on cytosolic or nuclear targets. Recently, extracellular vesicles (EVs) have been exploited as next-generation delivery modalities due to their natural role in intercellular communication and biocompatibility. However, fusion of protein of interest to a scaffold represents a widely used strategy for cargo enrichment in EVs, which could compromise the stability and functionality of cargo. Herein, we report intracellular delivery via EV-based approach (IDEA) that efficiently packages and delivers native proteins both in vitro and in vivo without the use of a scaffold. As a proof-of-concept, we applied the IDEA to deliver cyclic GMP-AMP synthase (cGAS), an innate immune sensor. The results showed that cGAS-carrying EVs activated interferon signaling and elicited enhanced antitumor immunity in multiple syngeneic tumor models. Combining cGAS EVs with immune checkpoint inhibition further synergistically boosted antitumor efficacy in vivo. Mechanistically, scRNA-seq demonstrated that cGAS EVs mediated significant remodeling of intratumoral microenvironment, revealing a pivotal role of infiltrating neutrophils in the antitumor immune milieu. Collectively, IDEA, as a universal and facile strategy, can be applied to expand and advance the development of protein-based therapeutics.

Unveiling the promise: Exosomes as game-changers in anti-infective therapy

Extracellular vesicles (EVs)-based intercellular communication (through exosomes, microvesicles, and apoptotic bodies) is conserved across all kingdoms of life. In recent years, exosomes have gained much attention for targeted pharmaceutical administration due to their unique features, nanoscale size, and capacity to significantly contribute to cellular communication. As drug delivery vehicles, exosomes have several advantages over alternative nanoparticulate drug delivery technologies. A key advantage lies in their comparable makeup to the body's cells, which makes them non-immunogenic. However, exosomes vesicles face several challenges, including a lack of an effective and standard production technique, decreased drug loading capacity, limited characterization techniques, and underdeveloped isolation and purification procedures. Exosomes are well known for their long-term safety and natural ability to transport intercellular nucleic acids and medicinal compounds across the blood-brain-barrier (BBB). Therefore, in addition to revealing new insights into exosomes' distinctiveness, the growing availability of new analytical tools may drive the development of next-generation synthetic systems. Herein, light is shed on exosomes as drug delivery vehicles in anti-infective therapy by reviewing the literature on primary articles published between 2002 and 2023. Additionally, the benefits and limitations of employing exosomes as vehicles for therapeutic drug delivery are also discussed.

Recent progress in engineered extracellular vesicles and their biomedical applications

AIMS

To present the recent update on the isolation, engineering techniques for extracellular vesicles, limitations associated with different isolation techniques, different biomedical applications, and challenges of engineered extracellular vesicles for the benefit of researchers from academic, industry, etc. MATERIALS AND METHODS: Peer-reviewed articles from most recognized journals were collected, and presented information was analyzed to discuss collection, chemical, electroporation, cellular, and membrane surface engineering to design extracellular vesicles for various therapeutic applications. In addition, we present the applications and limitations of techniques for the collection of extracellular vesicles.

KEY FINDINGS

There is a need for isolation techniques with the gold standard. However, advanced extracellular vesicle isolation techniques showed improved recovery, and purity of extracellular vesicles. Tumor therapy is a major part of the therapy section that illustrates the role of engineered extracellular vesicles in synergetic therapy such as phototherapy, theragnostic, and delivery of genetic materials. In addition, extracellular vesicles have shown their potential in the treatment of retinal disorders, neurodegenerative disease, tuberculosis, osteoporosis, inflammatory bowel disease, vaccine production, and wound healing.

SIGNIFICANCE

Engineered extracellular vesicles can deliver cargo to the specific cells, elicit an immune response and could be used for the development of the vaccines in the future. However, the progress is at the initial stage. Overall, this review will provide a comprehensive understanding and could serve as a reference for researchers in the clinical translation of engineered extracellular vesicles in different biomedical fields.

Exploring the clinical transition of engineered exosomes designed for intracellular delivery of therapeutic proteins

Extracellular vesicles, particularly exosomes, have emerged as promising drug delivery systems owing to their unique advantages, such as biocompatibility, immune tolerability, and target specificity. Various engineering strategies have been implemented to harness these innate qualities, with a focus on enhancing the pharmacokinetic and pharmacodynamic properties of exosomes via payload loading and surface engineering for active targeting. This concise review outlines the challenges in the development of exosomes as drug carriers and offers insights into strategies for their effective clinical translation. We also highlight preclinical studies that have successfully employed anti-inflammatory exosomes and suggest future directions for exosome therapeutics. These advancements underscore the potential for integrating exosome-based therapies into clinical practice, heralding promise for future medical interventions.

Self-powered triboelectric-responsive microneedles with controllable release of optogenetically engineered extracellular vesicles for intervertebral disc degeneration repair

Excessive exercise is an etiological factor of intervertebral disc degeneration (IVDD). Engineered extracellular vesicles (EVs) exhibit excellent therapeutic potential for disease-modifying treatments. Herein, we fabricate an exercise self-powered triboelectric-responsive microneedle (MN) assay with the sustainable release of optogenetically engineered EVs for IVDD repair. Mechanically, exercise promotes cytosolic DNA sensing-mediated inflammatory activation in senescent nucleus pulposus (NP) cells (the master cell population for IVD homeostasis maintenance), which accelerates IVDD. TREX1 serves as a crucial nuclease, and disassembly of TRAM1-TREX1 complex disrupts the subcellular localization of TREX1, triggering TREX1-dependent genomic DNA damage during NP cell senescence. Optogenetically engineered EVs deliver TRAM1 protein into senescent NP cells, which effectively reconstructs the elimination function of TREX1. Triboelectric nanogenerator (TENG) harvests mechanical energy and triggers the controllable release of engineered EVs. Notably, an optogenetically engineered EV-based targeting treatment strategy is used for the treatment of IVDD, showing promising clinical potential for the treatment of degeneration-associated disorders.

Trends in Developing Extracellular Vesicle-Based Therapeutics

Extracellular vesicles are nano-sized vesicles surrounded by lipid bilayers, and all cells release them to the extracellular environment for communication. Extracellular vesicles consist of molecules with various biological activities and can play essential roles as therapeutics, so they attract much attention as next-generation modalities to treat various diseases. As extracellular vesicles are cell-derived nanovesicles, they are favorable to be developed as therapeutics, but they also have limitations. In addition, there are a number of things to consider in terms of manufacturing, quality control, non-clinical studies, and clinical trials during the development of extracellular vesicle-based therapeutics. Meanwhile, as much attention has been paid to the potentials of extracellular vesicles as therapeutics, many biopharmaceutical companies are trying to develop extracellular vesicle-based therapeutics. This review will introduce the advantages and limitations of extracellular vesicles as therapeutics. In addition, it will cover things to consider during developing extracellular vesicle-based therapeutics and development cases of extracellular vesicle-based therapeutics.

Engineered exosomes: a potential therapeutic strategy for septic cardiomyopathy

Septic cardiomyopathy, a life-threatening complication of sepsis, can cause acute heart failure and carry a high mortality risk. Current treatments have limitations. Fortunately, engineered exosomes, created through bioengineering technology, may represent a potential new treatment method. These exosomes can both diagnose and treat septic cardiomyopathy, playing a crucial role in its development and progression. This article examines the strategies for using engineered exosomes to protect cardiac function and treat septic cardiomyopathy. It covers three innovative aspects: exosome surface modification technology, the use of exosomes as a multifunctional drug delivery platform, and plant exosome-like nanoparticle carriers. The article highlights the ability of exosomes to deliver small molecules, proteins, and drugs, summarizing several RNA molecules, proteins, and drugs beneficial for treating septic cardiomyopathy. Although engineered exosomes are a promising biotherapeutic carrier, they face challenges in clinical application, such as understanding the interaction mechanism with host cells, distribution within the body, metabolism, and long-term safety. Further research is essential, but engineered exosomes hold promise as an effective treatment for septic cardiomyopathy.

Effects of NF-κB Inhibitor on Sepsis Depend on the Severity and Phase of the Animal Sepsis Model

Hyperinflammation occurs in sepsis, especially in the early phase, and it could have both positive and negative effects on sepsis. Previously, we showed that a new concept of NF-κB inhibitor, exosome-based super-repressor IκBα (Exo-srIκB) delivery, has a beneficial effect on sepsis. Here, we further investigate the therapeutic effects of Exo-srIκB at different severities and phases of sepsis using an animal polymicrobial intra-abdominal infection model. We used a rat model of fecal slurry polymicrobial sepsis. First, we determined the survival effects of Exo-srIκB on sepsis according to the severity. We used two different severities of the animal sepsis model. The severe model had a mortality rate of over 50%. The mild/moderate model had a less than 30% mortality rate. Second, we administered the Exo-srIκB at various time points (1 h, 6 h, and 24 h after fecal slurry administration) to determine the therapeutic effect of Exo-srIκB at different phases of sepsis. Lastly, we determined the effects of the Exo-srIκB on cytokine production, arterial blood gas, electrolyte, and lactate. The survival gain was statistically significant in the severe sepsis model when Exo-srIκB was administered 6 h after sepsis. Interleukin 6 and interleukin-10 were significantly decreased in the kidney when administered with Exo-srIκB. The laboratory data showed that lactate, glucose, and potassium levels were significantly lowered in the NF-κB inhibitor group. In conclusion, Exo-srIκB exhibited a beneficial therapeutic effect when administered 6 h post fecal slurry administration in a severe sepsis model.

Relieving Macrophage Dysfunction by Inhibiting SREBP2 Activity: A Hypoxic Mesenchymal Stem Cells-Derived Exosomes Loaded Multifunctional Hydrogel for Accelerated Diabetic Wound Healing

Macrophage dysfunction is one of the primary factors leading to the delayed healing of diabetic wounds. Hypoxic bone marrow mesenchymal stem cells-derived exosomes (hyBMSC-Exos) have been shown to play an active role in regulating cellular function through the carried microRNAs. However, the administration of hyBMSC-Exos alone in diabetic wounds usually brings little effect, because the exosomes are inherently unstable and have a short retention time at the wounds. In this study, a multifunctional hydrogel based on gallic acid (GA) conjugated chitosan (Chi-GA) and partially oxidized hyaluronic acid (OHA) is prepared for sustained release of hyBMSC-Exos. The hydrogel not only exhibits needs-satisfying physicochemical properties, but also displays outstanding biological performances such as low hemolysis rate, strong antibacterial capacity, great antioxidant ability, and excellent biocompatibility. It has the ability to boost the stability of hyBMSC-Exos, leading to a continuous and gradual release of the exosomes at wound locations, ultimately enhancing the exosomes' uptake efficiency by target cells. Most importantly, hyBMSC-Exos loaded hydrogel shows an excellent ability to promote diabetic wound healing by regulating macrophage polarization toward M2 phenotype. This may be because exosomal miR-4645-5p and antioxidant property of the hydrogel synergistically inhibit SREBP2 activity in macrophages. This study presents a productive approach for managing diabetic wounds.

Mesenchymal stem cell‐derived extracellular vesicles: Recent therapeutics and targeted drug delivery advances

The targeted drug delivery field is rapidly advancing, focusing on developing biocompatible nanoparticles that meet rigorous criteria of non‐toxicity, biocompatibility, and efficient release of encapsulated molecules. Conventional synthetic nanoparticles (SNPs) face complications such as elevated immune responses, complex synthesis methods, and toxicity, which restrict their utility in therapeutics and drug delivery. Extracellular vesicles (EVs) have emerged as promising substitutes for SNPs, leveraging their ability to cross biological barriers, biocompatibility, reduced toxicity, and natural origin. Notably, mesenchymal stem cell‐derived EVs (MSC‐EVs) have garnered much curiosity due to their potential in therapeutics and drug delivery. Studies suggest that MSC‐EVs, the central paracrine contributors of MSCs, replicate the therapeutic effects of MSCs. This review explores the characteristics of MSC‐EVs, emphasizing their potential in therapeutics and drug delivery for various diseases, including CRISPR/Cas9 delivery for gene editing. It also delves into the obstacles and challenges of MSC‐EVs in clinical applications and provides insights into strategies to overcome the limitations of biodistribution and target delivery.

Single-Cell Sequencing Reveals MYOF-Enriched Monocyte/Macrophage Subcluster as a Favorable Prognostic Factor in Sepsis

This research utilized single-cell RNA sequencing to map the immune cell landscape in sepsis, revealing 28 distinct cell clusters and categorizing them into nine major types. Delving into the monocyte/macrophage subclusters, 12 unique subclusters are identified and pathway enrichment analyses are conducted using KEGG and GO, discovering enriched pathways such as oxidative phosphorylation and antigen processing. Further GSVA and AUCell assessments show varied activation of interferon pathways, especially in subclusters 4 and 11. The clinical correlation analysis reveals genes significantly linked to survival outcomes. Additionally, cellular differentiation in these subclusters is explored. Building on these insights, the differential gene expression within these subclusters is specifically scrutinized, which reveal MYOF as a key gene with elevated expression levels in the survivor group. This finding is further supported by in-depth pathway enrichment analysis and the examination of cellular differentiation trajectories, where MYOF's role became evident in the context of immune response regulation and sepsis progression. Validating the role of the MYOF gene in sepsis, a dose-dependent response to LPS in THP-1 cells and C57 mice is observed. Finally, inter-cellular communications are analyzed, particularly focusing on the MYOF+Mono/Macro subcluster, which indicates a pivotal role in immune regulation and potential therapeutic targeting.

Exosomal mediators in sepsis and inflammatory organ injury: unraveling the role of exosomes in intercellular crosstalk and organ dysfunction

Sepsis, a severe systemic inflammatory response to infection, remains a leading cause of morbidity and mortality worldwide. Exosomes, as mediators of intercellular communication, play a pivotal role in the pathogenesis of sepsis through modulating immune responses, metabolic reprogramming, coagulopathy, and organ dysfunction. This review highlights the emerging significance of exosomes in these processes. Initially, it provides an in-depth insight into exosome biogenesis and characterization, laying the groundwork for understanding their diverse and intricate functions. Subsequently, it explores the regulatory roles of exosomes in various immune cells such as neutrophils, macrophages, dendritic cells, T cells, and B cells. This analysis elucidates how exosomes are pivotal in modulating immune responses, thus contributing to the complexity of sepsis pathophysiology. Additionally, this review delves into the role of exosomes in the regulation of metabolism and subsequent organ dysfunction in sepsis. It also establishes a connection between exosomes and the coagulation cascade, which affects endothelial integrity and promotes thrombogenesis in sepsis. Moreover, the review discusses the dual role of exosomes in the progression and resolution of sepsis, exploring their complex involvement in inflammation and healing processes. Furthermore, it underscores their potential as biomarkers and therapeutic targets. Understanding these mechanisms presents new opportunities for novel interventions to mitigate the severe outcomes of sepsis, emphasizing the therapeutic promise of exosome research in critical care settings.

Applications of peptides in nanosystems for diagnosing and managing bacterial sepsis

Sepsis represents a critical medical condition stemming from an imbalanced host immune response to infections, which is linked to a significant burden of disease. Despite substantial efforts in laboratory and clinical research, sepsis remains a prominent contributor to mortality worldwide. Nanotechnology presents innovative opportunities for the advancement of sepsis diagnosis and treatment. Due to their unique properties, including diversity, ease of synthesis, biocompatibility, high specificity, and excellent pharmacological efficacy, peptides hold great potential as part of nanotechnology approaches against sepsis. Herein, we present a comprehensive and up-to-date review of the applications of peptides in nanosystems for combating sepsis, with the potential to expedite diagnosis and enhance management outcomes. Firstly, sepsis pathophysiology, antisepsis drug targets, current modalities in management and diagnosis with their limitations, and the potential of peptides to advance the diagnosis and management of sepsis have been adequately addressed. The applications have been organized into diagnostic or managing applications, with the last one being further sub-organized into nano-delivered bioactive peptides with antimicrobial or anti-inflammatory activity, peptides as targeting moieties on the surface of nanosystems against sepsis, and peptides as nanocarriers for antisepsis agents. The studies have been grouped thematically and discussed, emphasizing the constructed nanosystem, physicochemical properties, and peptide-imparted enhancement in diagnostic and therapeutic efficacy. The strengths, limitations, and research gaps in each section have been elaborated. Finally, current challenges and potential future paths to enhance the use of peptides in nanosystems for combating sepsis have been deliberately spotlighted. This review reaffirms peptides' potential as promising biomaterials within nanotechnology strategies aimed at improving sepsis diagnosis and management.

Extracellular vesicles and endothelial dysfunction in infectious diseases

Cardiovascular diseases (CVDs) remain the leading cause of mortality and morbidity globally. Studies have shown that infections especially bacteraemia and sepsis are associated with increased risks for endothelial dysfunction and related CVDs including atherosclerosis. Extracellular vesicles (EVs) are small, sealed membrane-derived structures that are released into body fluids and blood from cells and/or microbes and are critically involved in a variety of important cell functions and disease development, including intercellular communications, immune responses and inflammation. It is known that EVs-mediated mechanism(s) is important in the development of endothelial dysfunction in infections with a diverse spectrum of microorganisms including Escherichia coli, Candida albicans, SARS-CoV-2 (the virus for COVID-19) and Helicobacter pylori. H. pylori infection is one of the most common infections globally. During H. pylori infection, EVs can carry H. pylori components, such as lipopolysaccharide, cytotoxin-associated gene A, or vacuolating cytotoxin A, and transfer these substances into endothelial cells, triggering inflammatory responses and endothelial dysfunction. This review is to illustrate the important role of EVs in the pathogenesis of infectious diseases, and the development of endothelial dysfunction in infectious diseases especially H. pylori infection, and to discuss the potential mechanisms and clinical implications.

Regulation of cargo selection in exosome biogenesis and its biomedical applications in cancer

Extracellular vesicles (EVs), including exosomes, are increasingly recognized as potent mediators of intercellular communication due to their capacity to transport a diverse array of bioactive molecules. They assume vital roles in a wide range of physiological and pathological processes and hold significant promise as emerging disease biomarkers, therapeutic agents, and carriers for drug delivery. Exosomes encompass specific groups of membrane proteins, lipids, nucleic acids, cytosolic proteins, and other signaling molecules within their interior. These cargo molecules dictate targeting specificity and functional roles upon reaching recipient cells. Despite our growing understanding of the significance of exosomes in diverse biological processes, the molecular mechanisms governing the selective sorting and packaging of cargo within exosomes have not been fully elucidated. In this review, we summarize current insights into the molecular mechanisms that regulate the sorting of various molecules into exosomes, the resulting biological functions, and potential clinical applications, with a particular emphasis on their relevance in cancer and other diseases. A comprehensive understanding of the loading processes and mechanisms involved in exosome cargo sorting is essential for uncovering the physiological and pathological roles of exosomes, identifying therapeutic targets, and advancing the clinical development of exosome-based therapeutics.

Ultrasound-Assisted CRISPRi-Exosome for Epigenetic Modification of α-Synuclein Gene in a Mouse Model of Parkinson's Disease

Currently, there is a lack of effective treatment for Parkinson's disease (PD). In PD patients, aberrant methylation of SNCA (α-synuclein gene) has been reported and may be a potential therapeutic target. In this study, we established an epigenetic regulation platform based on an exosomal CRISPR intervention system. With the assist of focused ultrasound (FUS) opening the blood-brain barrier, engineered exosomes carrying RVG (rabies viral glycoprotein) targeting peptide, sgRNA (single guide RNA), and dCas9-DNMT3A (named RVG-CRISPRi-Exo) were efficiently delivered into the brain lesions and induced specific methylation of SNCA. In vivo, FUS combined with RVG-CRISPRi-Exo significantly improved motor performance, balance coordination, and neurosensitivity in PD mice, greatly down-regulated the elevation of α-synuclein (α-syn) caused by modeling, rescued cell apoptosis, and alleviated the progression of PD in mice. [18F]-FP-DTBZ imaging suggested that the synaptic function of the nigrostriatal pathway could be restored, which was conducive to the control of motor behavior in PD mice. Pyrosequencing results showed that RVG-CRISPRi-Exo could methylate CpG at specific sites of SNCA, and this fine-tuned editing achieved good therapeutic effects in PD model mice. In vitro, RVG-CRISPRi-Exo down-regulated SNCA transcripts and α-syn expression and relieved neuronal cell damage. Collectively, our findings provide a proof-of-principle for the development of targeted brain nanodelivery based on engineered exosomes and provide insights into epigenetic regulation of brain diseases.

NF-κB in biology and targeted therapy: new insights and translational implications

NF-κB signaling has been discovered for nearly 40 years. Initially, NF-κB signaling was identified as a pivotal pathway in mediating inflammatory responses. However, with extensive and in-depth investigations, researchers have discovered that its role can be expanded to a variety of signaling mechanisms, biological processes, human diseases, and treatment options. In this review, we first scrutinize the research process of NF-κB signaling, and summarize the composition, activation, and regulatory mechanism of NF-κB signaling. We investigate the interaction of NF-κB signaling with other important pathways, including PI3K/AKT, MAPK, JAK-STAT, TGF-β, Wnt, Notch, Hedgehog, and TLR signaling. The physiological and pathological states of NF-κB signaling, as well as its intricate involvement in inflammation, immune regulation, and tumor microenvironment, are also explicated. Additionally, we illustrate how NF-κB signaling is involved in a variety of human diseases, including cancers, inflammatory and autoimmune diseases, cardiovascular diseases, metabolic diseases, neurological diseases, and COVID-19. Further, we discuss the therapeutic approaches targeting NF-κB signaling, including IKK inhibitors, monoclonal antibodies, proteasome inhibitors, nuclear translocation inhibitors, DNA binding inhibitors, TKIs, non-coding RNAs, immunotherapy, and CAR-T. Finally, we provide an outlook for research in the field of NF-κB signaling. We hope to present a stereoscopic, comprehensive NF-κB signaling that will inform future research and clinical practice.

Micro Trojan horses: Engineering extracellular vesicles crossing biological barriers for drug delivery

The biological barriers of the body, such as the blood-brain, placental, intestinal, skin, and air-blood, protect against invading viruses and bacteria while providing necessary physical support. However, these barriers also hinder the delivery of drugs to target tissues, reducing their therapeutic efficacy. Extracellular vesicles (EVs), nanostructures with a diameter ranging from 30 nm to 10 μm secreted by cells, offer a potential solution to this challenge. These natural vesicles can effectively pass through various biological barriers, facilitating intercellular communication. As a result, artificially engineered EVs that mimic or are superior to the natural ones have emerged as a promising drug delivery vehicle, capable of delivering drugs to almost any body part to treat various diseases. This review first provides an overview of the formation and cross-species uptake of natural EVs from different organisms, including animals, plants, and bacteria. Later, it explores the current clinical applications, perspectives, and challenges associated with using engineered EVs as a drug delivery platform. Finally, it aims to inspire further research to help bioengineered EVs effectively cross biological barriers to treat diseases.

Exosome-Mediated Impact on Systemic Metabolism

Exosomes are small extracellular vesicles that carry lipids, proteins, and microRNAs (miRNAs). They are released by all cell types and can be found not only in circulation but in many biological fluids. Exosomes are essential for interorgan communication because they can transfer their contents from donor to recipient cells, modulating cellular functions. The miRNA content of exosomes is responsible for most of their biological effects, and changes in exosomal miRNA levels can contribute to the progression or regression of metabolic diseases. As exosomal miRNAs are selectively sorted and packaged into exosomes, they can be useful as biomarkers for diagnosing diseases. The field of exosomes and metabolism is expanding rapidly, and researchers are consistently making new discoveries in this area. As a result, exosomes have great potential for a next-generation drug delivery platform for metabolic diseases.

ASC-expressing pyroptotic extracellular vesicles alleviate sepsis by protecting B cells

Pyroptosis is an inflammatory programmed cell death process characterized by membrane rupture. Interestingly, pyroptotic cells can generate plenty of nanosized vesicles. Non-inflammatory apoptotic cell death-derived apoptotic vesicles (apoVs) were systemically characterized and displayed multiple physiological functions and therapeutic potentials. However, the characteristics of pyroptotic cell-generated extracellular vesicles (EVs) are largely unknown. Here, we identified a group of pyroptotic EVs (pyroEVs) from in vitro cultured pyroptotic mesenchymal stem cells (MSCs), as well as from septic mouse blood. Compared with apoVs, pyroEVs express similar levels of annexin V, calreticulin, and common EV markers, but express a decreased level of apoptotic marker cleave caspase-3. PyroEVs, but not apoVs and exosomes, specifically express pyroptotic maker apoptosis-associated speck-like protein containing CARD (ASC). More importantly, MSC-derived pyroEVs protect B cells in the spleen and bone marrow to relieve inflammatory responses and enhance the survival rate of the septic mice. Mechanistically, pyroEV membrane-expressed ASC binds to B cells to repress cell death by repressing Toll-like receptor 4. This study uncovered the characteristics of pyroEVs and their therapeutic role in sepsis and B cell-mediated immune response.

Advances and challenges in clinical applications of tumor cell-derived extracellular vesicles

Extracellular vesicles (EVs) are a class of substances that feature vesicle-like structures. Initially deemed to be "biological waste", recent studies have highlighted the crucial role of EVs in mediating information communication between cells by transporting bioactive components. Specifically, tumor cell-derived extracellular vesicles (TEVs) contain components that can be utilized for disease diagnosis and as vaccines to activate the immune system. Moreover, since TEVs have a phospholipid bilayer shell and can transport exogenous substances, they are being increasingly explored as drug delivery vehicles in anti-tumor therapy. TEVs have proven highly compatible with their corresponding tumor cells, allowing for efficient drug delivery and exerting killing effects on tumor cells through various mechanisms such as domino effects, lysosomal pathways, and inhibition of drug efflux from tumor tissues. Despite these promising developments, challenges remain in the clinical applications of EVs derived from tumor cells. This paper outlines the current advances and limitations in this field, highlighting the potential of TEVs as a powerful tool for combating cancer.

Deciphering the molecular classification of pediatric sepsis: integrating WGCNA and machine learning-based classification with immune signatures for the development of an advanced diagnostic model

Introduction: Pediatric sepsis (PS) is a life-threatening infection associated with high mortality rates, necessitating a deeper understanding of its underlying pathological mechanisms. Recently discovered programmed cell death induced by copper has been implicated in various medical conditions, but its potential involvement in PS remains largely unexplored. Methods: We first analyzed the expression patterns of cuproptosis-related genes (CRGs) and assessed the immune landscape of PS using the GSE66099 dataset. Subsequently, PS samples were isolated from the same dataset, and consensus clustering was performed based on differentially expressed CRGs. We applied weighted gene co-expression network analysis to identify hub genes associated with PS and cuproptosis. Results: We observed aberrant expression of 27 CRGs and a specific immune landscape in PS samples. Our findings revealed that patients in the GSE66099 dataset could be categorized into two cuproptosis clusters, each characterized by unique immune landscapes and varying functional classifications or enriched pathways. Among the machine learning approaches, Extreme Gradient Boosting demonstrated optimal performance as a diagnostic model for PS. Discussion: Our study provides valuable insights into the molecular mechanisms underlying PS, highlighting the involvement of cuproptosis-related genes and immune cell infiltration.

An overview of the mechanisms and potential roles of extracellular vesicles in septic shock

Septic shock, a subset of sepsis, is a fatal condition associated with high morbidity and mortality. However, the pathophysiology of septic shock is not fully understood. Moreover, the diagnostic markers employed for identifying septic shock lack optimal sensitivity and specificity. Current treatment protocols for septic shock have not been effective in lowering the mortality rate of patients. Most cells exhibit the capability to release extracellular vesicles (EVs), nanoscale vesicles that play a vital role in intercellular communication. In recent years, researchers have investigated the potential role of EVs in the pathogenesis, diagnosis, and treatment of different diseases, such as oncological, neurological, and cardiovascular diseases, as well as diabetes and septic shock. In this article, we present an overview of the inhibitory and facilitative roles that EVs play in the process of septic shock, the potential role of EVs in the diagnosis of septic shock, and the potential therapeutic applications of both native and engineered EVs in the management of septic shock.

Intracellular Protein Delivery: Approaches, Challenges, and Clinical Applications

Protein biologics are powerful therapeutic agents with diverse inhibitory and enzymatic functions. However, their clinical use has been limited to extracellular applications due to their inability to cross plasma membranes. Overcoming this physiological barrier would unlock the potential of protein drugs for the treatment of many intractable diseases. In this review, we highlight progress made toward achieving cytosolic delivery of recombinant proteins. We start by first considering intracellular protein delivery as a drug modality compared to existing Food and Drug Administration-approved drug modalities. Then, we summarize strategies that have been reported to achieve protein internalization. These techniques can be broadly classified into 3 categories: physical methods, direct protein engineering, and nanocarrier-mediated delivery. Finally, we highlight existing challenges for cytosolic protein delivery and offer an outlook for future advances.

Bioactive Phosphorus Dendrimers as a Universal Protein Delivery System for Enhanced Anti-inflammation Therapy

Nanocarrier-based cytoplasmic protein delivery offers opportunities to develop protein therapeutics; however, many delivery systems are positively charged, causing severe toxic effects. For enhanced therapeutics, it is also of great importance to design nanocarriers with intrinsic bioactivity that can be integrated with protein drugs due to the limited bioactivity of proteins alone for disease treatment. We report here a protein delivery system based on anionic phosphite-terminated phosphorus dendrimers with intrinsic anti-inflammatory activity. A phosphorus dendrimer termed AK-137 with optimized anti-inflammatory activity was selected to complex proteins through various physical interactions. Model proteins such as bovine serum albumin, ribonuclease A, ovalbumin, and fibronectin (FN) can be transfected into cells to exert their respective functions, including cancer cell apoptosis, dendritic cell maturation, or macrophage immunomodulation. Particularly, the constructed AK-137@FN nanocomplexes display powerful therapeutic effects in acute lung injury and acute gout arthritis models by integrating the anti-inflammatory activity of both the carrier and protein. The developed anionic phosphite-terminated phosphorus dendrimers may be employed as a universal carrier for protein delivery and particularly utilized to deliver proteins and fight different inflammatory diseases with enhanced therapeutic efficacy.

Nanoparticles Based on Natural Lipids Reveal Extent of Impacts of Designed Physical Characteristics on Biological Functions

Nanoparticles based on lipids (LNPs) are essential in pharmaceuticals and intercellular communication, and their design parameters span a diverse range of molecules and assemblies. In bridging the gap in insight between extracellular vesicles (EVs) and synthetic LNPs, one challenge is understanding their in-cell/in-body behavior when simultaneously assessing more than one physical characteristic. Herein, we demonstrate comprehensive evaluation of LNP behavior by using LNPs based on natural lipids (N-LNPs) with designed physical characteristics: size tuned using microfluidic methods, surface fluidity designed based on EV components, and stiffness tuned using biomolecules. We produce 12 types of N-LNPs having different physical characteristics─two sizes, three membrane fluidities, and two stiffnesses for in vitro evaluation─and evaluate cellular uptake vitality and endocytic pathways of N-LNPs based on the physical characteristics of N-LNPs. To reveal the extent of the impact of the predesigned physical characteristics of N-LNPs on cellular uptakes in vivo, we also carried out animal experiments with four types of N-LNPs having different sizes and fluidities. The use of N-LNPs has helped to clarify the extent of the impact of inextricably related, designed physical characteristics on transportation and provided a bidirectional guidepost for the streamlined design and understanding of the biological functions of LNPs.

Efficacy of Allogeneic and Xenogeneic Exosomes for the Treatment of Canine Atopic Dermatitis: A Pilot Study

Canine atopic dermatitis (CAD) is a genetically predisposed inflammatory pruritic skin disease. The available treatments for CAD have several adverse effects and vary in efficacy, indicating the need for the development of improved treatments. In this study, we aimed to elucidate the therapeutic effects of allogeneic and xenogeneic exosomes on CAD. Six laboratory beagle dogs with CAD were randomly assigned to three treatment groups: control, canine exosome (cExos), or human exosome (hExos) groups. Dogs in the cExos and hExos groups were intravenously administered 1.5 mL of cExos (5 × 1010) and hExos (7.5 × 1011) solutions, respectively, while those in the control group were administered 1.5 mL of normal saline three times per week for 4 weeks. Skin lesion score and transepidermal water loss decreased in cExos and hExos groups compared with those in the control group. The exosome treatments decreased the serum levels of inflammatory cytokines (interferon-γ, interleukin-2, interleukin-4, interleukin-12, interleukin-13, and interleukin-31) but increased those of anti-inflammatory cytokines (interleukin-10 and transforming growth factor-β), indicating the immunomodulatory effect of exosomes. Skin microbiome analysis revealed that the exosome treatments alleviated skin bacterial dysbiosis. These results suggest that allogeneic and xenogeneic exosome therapy may alleviate CAD in dogs.

Exosome-mediated delivery of super-repressor IκBα alleviates inflammation and joint damages in rheumatoid arthritis

BACKGROUND

This study aims to investigate the potential anti-inflammatory effects of exosomes engineered to carry super-repressor IκB (Exo-srIκB), an exosome-based NF-κB inhibitor, in the context of RA.

METHODS

Peripheral blood mononuclear cells (PBMCs) and synovial fluid mononuclear cells (SFMCs) were collected from patients diagnosed with RA and treated with Exo-srIκB to test the therapeutic potential. Flow cytometry analysis was performed to assess the production of inflammatory cytokines (IL-17A and GM-CSF) by the cells. ELISA was utilized to measure the levels of TNF-α, IL-17A, IL-6, and GM-CSF. Arthritis was induced in SKG mice by intraperitoneal injection of curdlan. DBA/1 J mice were used in collagen-induced arthritis (CIA) experiments. After the development of arthritis, mice were injected with either Exo-Naïve (control exosome) or Exo-srIκB. Arthritis scores were recorded biweekly, and histological observations of the ankle joint were conducted using H&E and safranin-O staining. Additionally, bone erosion was evaluated using micro-CT imaging.

RESULTS

In the ex vivo study involving human PBMCs and SFMCs, treatment with Exo-srIκB demonstrated a notable reduction in inflammatory cytokines. Furthermore, in both the SKG and CIA models, Exo-srIκB treatment exhibited significant reductions in inflammation, cartilage destruction, and bone erosion within the joint tissues when compared to the Exo-Naive control group. Additionally, the radiographic score assessed through microCT showed a significant decrease compared to the Exo-Naive control group.

CONCLUSION

Overall, these findings suggest that Exo-srIκB possesses anti-inflammatory properties in human RA cells and animal models, making it a promising therapeutic candidate for the treatment of RA.

Macrophage-derived exosomal miRNA-141 triggers endothelial cell pyroptosis by targeting NLRP3 to accelerate sepsis progression

Sepsis, critical condition marked by severe organ dysfunction from uncontrolled infection, involves the endothelium significantly. Macrophages, through paracrine actions, play a vital role in sepsis, but their mechanisms in sepsis pathogenesis remain elusive. Objective: We aimed to explore how macrophage-derived exosomes with low miR-141 expression promote pyroptosis in endothelial cells (ECs). Exosomes from THP-1 cell supernatant were isolated and characterized. The effects of miR-141 mimic/inhibitor on apoptosis, proliferation, and invasion of Human Umbilical Vein Endothelial Cells (HUVECs) were assessed using flow cytometry, CCK-8, and transwell assays. Key pyroptosis-related proteins, including caspase-1, IL-18, IL-1β, NLR Family Pyrin Domain Containing 3 (NLRP3), ASC, and cleaved-GSDMD, were analyzed via Western blot. The interaction between miR-141 and NLRP3 was studied using RNAhybrid v2.2 and dual-Luciferase reporter assays. The mRNA and protein level of NLRP3 after exosomal miR-141 inhibitor treatment was detected by qPCR and Western blot, respectively. Exosomes were successfully isolated. miR-141 mimic reduced cell death and pyroptosis-related protein expression in HUVECs, while the inhibitor had opposite effects, increasing cell death, and enhancing pyroptosis protein expression. Additionally, macrophage-derived exosomal miR-141 inhibitor increased cell death and pyroptosis-related proteins in HUVECs. miR-141 inhibits NLRP3 transcription. Macrophages facilitate sepsis progression by secreting miR-141 decreased exosomes to activate NLRP3-mediated pyroptosis in ECs, which could be a potentially valuable target of sepsis therapy.

Protective effect of small extracellular vesicles (EVs) derived from ACE2-modified human umbilical cord mesenchymal stem cells against renal ischemia-reperfusion injury

AIM

Acute kidney injury is a severe disease that is closely associated with substantial morbidity and mortality. The most common cause of AKI is renal ischemia-reperfusion injury. Mesenchymal stem cells (MSCs) have previously been shown to have renoprotective effects. However, extracellular vesicles secreted by MSCs are thought to be the key for the therapeutic effects of MSCs. This study investigated whether small EVs derived from ACE2-modified human umbilical cord MSCs could alleviate RIRI and explored their underlying molecular mechanisms METHODS: A lentivirus carrying an ACE2 overexpression vector was constructed and used to infect MSCs. The small EVs were isolated from MSC-conditioned medium by ultracentrifugation. HK-2 cells were cocultured with MSC-ACE2-EVs and subjected to hypoxia/reoxygenation injury. MSCs-ACE2-EVs were injected into RIRI mice. Biochemical and morphological characteristics were assessed, and the levels of inflammatory-related factors, oxidative stress products, and apoptosis in HK-2 cells and kidney tissues were assessed RESULTS: In vitro, MSC-ACE2-EVs had stronger anti-inflammatory, antioxidative stress, and antiapoptotic effects in HK-2 cells subjected to H/R than MSC-NC-EVs. In vivo, MSC-ACE2-EVs could target the injured kidney, reduce blood creatinine and urea nitrogen levels, and protect the kidney from I/R, and this effect may have been related to the activation of the Nrf2/HO-1 signalling pathway CONCLUSION: Taken together, our results demonstrated the anti-inflammatory, antioxidative stress, and antiapoptotic effects of MSC-ACE2-EVs, which protected against I/R injury in vitro and vivo. MSC-ACE2-EVs may be therapeutic agents for RIRI.

The Transcriptome Analysis of Circular RNAs Between the Doxorubicin- Induced Cardiomyocytes and Bone Marrow Mesenchymal Stem Cells- Derived Exosomes Treated Ones

AIM

To analyze the sequencing results of circular RNAs (circRNAs) in cardiomyocytes between the doxorubicin (DOX)-injured group and exosomes treatment group. Moreover, to offer potential circRNAs possibly secreted by exosomes mediating the therapeutic effect on DOX-induced cardiotoxicity for further study.

METHODS

The DOX-injured group (DOX group) of cardiomyocytes was treated with DOX, while an exosomes-treated group of injured cardiomyocytes were cocultured with bone marrow mesenchymal stem cells (BMSC)-derived exosomes (BEC group). The high-throughput sequencing of circRNAs was conducted after the extraction of RNA from cardiomyocytes. The differential expression of circRNA was analyzed after identifying the number, expression, and conservative of circRNAs. Then, the target genes of differentially expressed circRNAs were predicted based on the targetscan and Miranda database. Next, the GO and KEGG enrichment analyses of target genes of circRNAs were performed. The crucial signaling pathways participating in the therapeutic process were identified. Finally, a real-time quantitative polymerase chain reaction experiment was conducted to verify the results obtained by sequencing.

RESULTS

Thirty-two circRNAs are differentially expressed between the two groups, of which twenty-three circRNAs were elevated in the exosomes-treated group (BEC group). The GO analysis shows that target genes of differentially expressed circRNAs are mainly enriched in the intracellular signalactivity, regulation of nucleic acid-templated transcription, Golgi-related activity, and GTPase activator activity. The KEGG analysis displays that they were involved in the autophagy biological process and NOD-like receptor signaling pathway. The verification experiment suggested that mmu_circ_0000425 (ID: 116324210) was both decreased in the DOX group and elevated in BEC group, which was consistent with the result of sequencing.

CONCLUSION

mmu_circ_0000425 in exosomes derived from bone marrow mesenchymal stem cells (BMSC) may have a therapeutic role in alleviating doxorubicin-induced cardiotoxicity (DIC).

Engineered Exosomes for Drug Delivery in Cancer Therapy: A Promising Approach and Application

A significant amount of research effort is currently focused on investigating the role of exosomes in various cancers. These tiny vesicles, apart from acting as biomarkers, also play a crucial role in tumor formation and development. Several studies have demonstrated that exosomes can be a drug delivery vehicle for cancer therapy. In this paper, we highlight the key advantages of exosomes as a drug delivery candidate, with a particular focus on their low immunogenicity, natural targeting ability and suitable mechanical properties. Furthermore, we propose that the selection of appropriate exosomes and drug loading methods based on therapeutic goals and product heterogeneity is essential for preparing engineered exosomes. We comprehensively analyzed the superiorities of current drug-loading methods to improve the creation of designed exosomes. Moreover, we systematically review the applications of engineered exosomes in various therapies such as immunotherapy, gene therapy, protein therapy, chemotherapy, indicating that engineered exosomes have the potential to be reliable and, safe drug carriers that can address the unmet needs in cancer clinical practice.

Recent advances in extracellular vesicle engineering and its applications to regenerative medicine

Extracellular vesicles (EVs) are nanosized particles that are released from cells and reflect the characteristics of the mother cell. Recently, the EVs have been used in several types of studies across many different fields. In the field of EV research, multiple cell culture and EV isolation techniques have been highlighted in importance. Various strategies, including exclusive component culture media, three-dimensional (3D) cultures, and hypoxic conditions, have been proposed for the cell culture to control function of the EVs. Ultracentrifugation, ultrafiltration, precipitation, and tangential flow filtration (TFF) have been utilized for EV isolation. Although isolated EVs have their own functionalities, several researchers are trying to functionalize EVs by applying various engineering approaches. Gene editing, exogenous, endogenous, and hybridization methods are the four well-known types of EV functionalization strategies. EV engineered through these processes has been applied in the field of regenerative medicine, including kidney diseases, osteoarthritis, rheumatoid arthritis, nervous system-related diseases, and others. In this review, it was focused on engineering approaches for EV functionalization and their applications in regenerative medicine.

Exosomal miR-181d-5p Derived from Rapamycin-Conditioned MDSC Alleviated Allograft Rejection by Targeting KLF6

Immune rejection and side effects of long-term administration of immunosuppressants are the two major obstacles to allograft acceptance and tolerance. The immunosuppressive extracellular vesicles (EVs)-based approach has been proven to be effective in treating autoimmune/inflammatory disorders. Herein, the anti-rejection advantage of exosomes (Rapa-Exo) from rapamycin-conditioned myeloid-derived suppressor cells (MDSCs) over exosomes (Exo-Nor) from the untreated MDSCs is shown. The exosomal small RNA sequencing and loss-of-function assays reveal that the anti-rejection effect of Rapa-Exo functionally relies on miR-181d-5p. Through target prediction and double-luciferase reporter assay, Kruppel-like factor (KLF) 6 is identified as a direct target of miR-181d-5p. Finally, KLF6 knockdown markedly resolves inflammation and prolongs the survival of corneal allografts. Taken together, these findings support that Rapa-Exo executes an anti-rejection effect, highlighting the immunosuppressive EVs-based treatment as a promising approach in organ transplantation.

Surface modification strategies in translocating nano-vesicles across different barriers and the role of bio-vesicles in improving anticancer therapy

Nanovesicles and bio-vesicles (BVs) have emerged as promising tools to achieve targeted cancer therapy due to their ability to overcome many of the key challenges currently being faced with conventional chemotherapy. These challenges include the diverse and often complex pathophysiology involving the progression of cancer, as well as the various biological barriers that circumvent therapeutic molecules reaching their target site in optimum concentration. The scientific evidence suggests that surface-functionalized nanovesicles and BVs camouflaged nano-carriers (NCs) both can bypass the established biological barriers and facilitate fourth-generation targeting for the improved regimen of treatment. In this review, we intend to emphasize the role of surface-functionalized nanovesicles and BVs camouflaged NCs through various approaches that lead to an improved internalization to achieve improved and targeted oncotherapy. We have explored various strategies that have been employed to surface-functionalize and biologically modify these vesicles, including the use of biomolecule functionalized target ligands such as peptides, antibodies, and aptamers, as well as the targeting of specific receptors on cancer cells. Further, the utility of BVs, which are made from the membranes of cells such as mesenchymal stem cells (MSCs), white blood cells (WBCs), red blood cells (RBCs), platelets (PLTs) as well as cancer cells also been investigated. Lastly, we have discussed the translational challenges and limitations that these NCs can encounter and still need to be overcome in order to fully realize the potential of nanovesicles and BVs for targeted cancer therapy. The fundamental challenges that currently prevent successful cancer therapy and the necessity of novel delivery systems are in the offing.

Analysis of microRNA expression in rat kidneys after VEGF inhibitor treatment under different degrees of hypoxia

Previously, we found that the incidence of kidney injury in patients with chronic hypoxia was related to the partial pressure of arterial oxygen. However, at oxygen concentrations that contribute to kidney injury, the changes in the relationship between microRNAs (miRNAs) and the hypoxia-inducible factor-1α (HIF-1α)-vascular endothelial growth factor (VEGF) axis and the key miRNAs involved in this process have not been elucidated. Therefore, we elucidated the relationship between VEGF and kidney injury at different oxygen concentrations and the mechanisms mediated by miRNAs. Sprague-Dawley rats were exposed to normobaric hypoxia and categorized into six groups based on the concentration of the oxygen inhaled and injection of the angiogenesis inhibitor bevacizumab, a humanized anti-VEGF monoclonal antibody. Renal tissue samples were processed to determine pathological and morphological changes and HIF-1α, VEGF, and miRNA expression. We performed a clustering analysis of high-risk pathways and key hub genes. The results were validated using two Gene Expression Omnibus datasets (GSE94717 and GSE30718). As inhaled oxygen concentration decreased, destructive changes in the kidney tissues became more severe. Although the kidney possesses a self-protective mechanism under an intermediate degree of hypoxia (10% O2), bevacizumab injections disrupted this mechanism, and VEGF expression was associated with the ability of the kidney to repair itself. rno-miR-124-3p was identified as a crucial miRNA; a key gene target, Mapk14, was identified during this process. VEGF plays an important role in kidney protection from injury under different hypoxia levels. Specific miRNAs and their target genes may serve as biomarkers that provide new insights into kidney injury treatment.NEW & NOTEWORTHY Renal tolerance to hypoxic environments is limited, and the degree of hypoxia does not show a linear relationship with angiogenesis. VEGF plays an important role in the kidney's self-protective mechanism under different levels of hypoxia. miR-124-3p may be particularly important in kidney repair, and it may modulate VEGF expression through the miR-124-3p/Mapk14 signaling pathway. These microRNAs may serve as biomarkers that provide new insights into kidney injury treatment.

The role of neutrophil extracellular traps in sepsis and sepsis-related acute lung injury

Neutrophils release neutrophil extracellular traps (NETs) to trap pathogenic microorganisms. NETs are involved in the inflammatory response and bacterial killing and clearance. However, their excessive activation can lead to an inflammatory storm in the body, which may damage tissues and cause organ dysfunction. Organ dysfunction is the main pathophysiological cause of sepsis and also a cause of the high mortality rate in sepsis. Acute lung injury caused by sepsis accounts for the highest proportion of organ damage in sepsis. NET formation can lead to the development of sepsis because by promoting the release of interleukin-1 beta, interleukin-8, and tumor necrosis factor-alpha, thereby accelerating acute lung injury. In this review, we describe the critical role of NETs in sepsis-associated acute lung injury and review the current knowledge and novel therapeutic approaches.