Research Progress in the Application of Exosomes in Immunotherapy

Nanomaterials for delivery of drugs and genes to disrupt notch signaling pathway in breast cancer

Breast cancer, marked by considerable heterogeneity and intricate molecular subgroups, poses substantial obstacles to therapy. Epithelial-mesenchymal transition (EMT) and the existence of tumor-initiating cells (TICs) facilitate treatment resistance, metastasis, and worse prognosis. The Notch signaling system has garnered significant interest for its involvement in promoting epithelial-mesenchymal transition (EMT), maintaining tumor-initiating cells (TIC), and facilitating cancer progression, especially in truculent subtypes such as triple-negative breast cancer (TNBC). Targeting the Notch system represents a promising therapeutic strategy; nevertheless, traditional inhibitors frequently encounter obstacles, including inadequate selectivity and bioavailability. Nanocarrier-based drug delivery systems provide novel therapeutic strategies to these difficulties by augmenting the targeted delivery of Notch inhibitors and enhancing therapeutic efficacy. Solid lipid nanoparticles (SLNs), polymeric nanoparticles, lipid-based nanocarriers, and micelles exhibit promise in delivering Notch inhibitors to neoplastic cells, altering the Notch signaling pathway, and surmounting drug resistance. This review examines recent breakthroughs in nanocarrier systems aimed at the Notch signaling pathway in breast cancer, highlighting the therapeutic potential of integrating nanomedicine with Notch inhibition to disrupt epithelial-mesenchymal transition (EMT), tumor-initiating cells (TICs), and metastasis, thereby enhancing clinical outcomes.

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.

Immunomodulatory Significance of Mast Cell Exosomes (MC-EXOs) in Immune Response Coordination

Mast cells (MCs) communicate with other cells by direct cell-to-cell interaction, secreting mediators, and releasing exosomes (EXOs). MC-exosomes (MC-EXOs) contain proteins, lipids, mRNAs, and noncoding RNAs (ncRNAs), exhibit typical EXO markers such as heat shock proteins, tetraspanins, tumor susceptibility gene 101 protein (TSG101), and ALG-2-interacting protein X (ALIX), and are released constitutively or following MC degranulation. MC-EXOs also have signature MC markers like FcεRI and KIT (CD117), which allows for their identification and comparison with other EXO populations. Following their release, MC-EXOs may interact with the recipient cell(s) directly or be internalized and then release their protein and nucleic acid content. This may contribute to the regulation of immune responses and other biological processes and reprogramming of recipient cells. MC-EXO proteins may integrate and become a functional part of the recipient cell membrane. The mRNA transferred by MC-EXOs is functional and the transfer of exosomal RNA to other MCs results in the expression of donor MC proteins in the recipient MCs. Moreover, MCs may function as the recipients of EXOs that are released by other non-immune and immune cells, altering the secretome of MCs. In this review, we focus on how MC-EXOs modulate the biology of other cells and vice versa; and we highlight the role of MC-EXOs in the pathogenesis of allergic and non-allergic diseases.

Immunomodulatory effect of PLGA-encapsulated mesenchymal stem cells-derived exosomes for the treatment of allergic rhinitis

Introduction

Allergic rhinitis (AR) is an upper airway inflammatory disease of the nasal mucosa. Conventional treatments such as symptomatic pharmacotherapy and allergen-specific immunotherapy have considerable limitations and drawbacks. As an emerging therapy with regenerative potential and immunomodulatory effect, mesenchymal stem cell-derived exosomes (MSC-Exos) have recently been trialed for the treatment of various inflammatory and autoimmune diseases.

Methods

In order to achieve sustained and protected release of MSC-Exos for intranasal administration, we fabricated Poly(lactic-co-glycolic acid) (PLGA) micro and nanoparticles-encapsulated MSC-Exos (PLGA-Exos) using mechanical double emulsion for local treatment of AR. Preclinical in vivo imaging, ELISA, qPCR, flow cytometry, immunohistochemical staining, and multiomics sequencing were used for phenotypic and mechanistic evaluation of the therapeutic effect of PLGA-Exos in vitro and in vivo.

Results

The results showed that our PLGA platform could efficiently encapsulate and release the exosomes in a sustained manner. At protein level, PLGA-Exos treatment upregulated IL-2, IL-10 and IFN-γ, and downregulated IL-4, IL-17 and antigen-specific IgE in ovalbumin (OVA)-induced AR mice. At cellular level, exosomes treatment reduced Th2 cells, increased Tregs, and reestablished Th1/Th2 balance. At tissue level, PLGA-Exos significantly attenuated the infiltration of immune cells (e.g., eosinophils and goblet cells) in nasal mucosa. Finally, multiomics analysis discovered several signaling cascades, e.g., peroxisome proliferator-activated receptor (PPAR) pathway and glycolysis pathway, that might mechanistically support the immunomodulatory effect of PLGA-Exos.

Discussion

For the first time, we present a biomaterial-facilitated local delivery system for stem cell-derived exosomes as a novel and promising strategy for AR treatment.

Exosomes as drug delivery systems in glioma immunotherapy

Recently, the significant benefits of cancer immunotherapy for most cancers have been demonstrated in clinical and preclinical studies. However, the efficacy of these immunotherapies for gliomas is limited, owing to restricted drug delivery and insufficient immune activation. As drug carriers, exosomes offer the advantages of low toxicity, good biocompatibility, and intrinsic cell targeting, which could enhance glioma immunotherapy efficacy. However, a review of exosome-based drug delivery systems for glioma immunotherapy has not been presented. This review introduces the current problems in glioma immunotherapy and the role of exosomes in addressing these issues. Meanwhile, preparation and application strategies of exosome-based drug delivery systems for glioma immunotherapy are discussed, especially for enhancing immunogenicity and reversing the immunosuppressive tumor microenvironment. Finally, we briefly describe the challenges of exosome-based drug delivery systems in clinical translation. We anticipate that this review will guide the use of exosomes as drug carriers for glioma immunotherapy.

Pro-endothelialization of nitinol alloy cardiovascular stents enhanced by the programmed assembly of exosomes and endothelial affinity peptide

Stent implantation is one of the most effective methods for the treatment of atherosclerosis. Nitinol stent is a type of stent with good biocompatibility and relatively mature development; however, it cannot effectively achieve long-term anticoagulation and early endothelialization. In this study, nitinol surfaces with the programmed assembly of heparin, exosomes from endothelial cells, and endothelial affinity peptide (REDV) were fabricated through layer-by-layer assembly technology and click-chemistry, and then exosomes/REDV-modified nitinol interface (ACC-Exo-REDV) was prepared. ACC-Exo-REDV could promote the rapid proliferation and adhesion of endothelial cells and achieve anticoagulant function in the blood. Besides, ACC-Exo-REDV had excellent anti-inflammatory properties and played a positive role in the transformation of macrophage from the pro-inflammatory to anti-inflammatory phenotype. Ex vivo and in vivo experiments demonstrated the effectiveness of ACC-Exo-REDV in preventing thrombosis and hyperplasia formation. Hence, the programmed assembly of exosome interface could contribute to endothelialization and have potential application on the cardiovascular surface modification to prevent stent thrombosis and restenosis.

Milk: A Natural Guardian for the Gut Barrier

The gut barrier plays an important role in health maintenance by preventing the invasion of dietary pathogens and toxins. Disruption of the gut barrier can cause severe intestinal inflammation. As a natural source, milk is enriched with many active constituents that contribute to numerous beneficial functions, including immune regulation. These components collectively serve as a shield for the gut barrier, protecting against various threats such as biological, chemical, mechanical, and immunological threats. This comprehensive review delves into the active ingredients in milk, encompassing casein, α-lactalbumin, β-lactoglobulin, lactoferrin, the milk fat globular membrane, lactose, transforming growth factor, and glycopeptides. The primary focus is to elucidate their impact on the integrity and function of the gut barrier. Furthermore, the implications of different processing methods of dairy products on the gut barrier protection are discussed. In conclusion, this study aimed to underscore the vital role of milk and dairy products in sustaining gut barrier health, potentially contributing to broader perspectives in nutritional sciences and public health.

Circulating T cell specific extracellular vesicle profiles in cardiac allograft acute cellular rejection

There is a critical need for biomarkers of acute cellular rejection (ACR) in organ transplantation. We hypothesized that ACR leads to changes in donor-reactive T cell small extracellular vesicle (sEV) profiles in transplant recipient circulation that match the kinetics of alloreactive T cell activation. In rodent heart transplantation, circulating T cell sEV quantities (P < .0001) and their protein and mRNA cargoes showed time-specific expression of alloreactive and regulatory markers heralding early ACR in allogeneic transplant recipients but not in syngeneic transplant recipients. Next generation sequencing of their microRNA cargoes identified novel candidate biomarkers of ACR, which were validated by stem loop quantitative reverse transcription polymerase chain reaction (n = 10). Circulating T cell sEVs enriched from allogeneic transplant recipients mediated targeted cytotoxicity of donor cardiomyocytes by apoptosis assay (P < .0001). Translation of the concept and EV methodologies to clinical heart transplantation demonstrated similar upregulation of circulating T cell sEV profiles at time points of grade 2 ACR (n = 3 patients). Furthermore, T cell receptor sequencing of T cell sEV mRNA cargo demonstrated expression of T cell clones with intact complementarity determining region 3 signals. These data support the diagnostic potential of T cell sEVs as noninvasive biomarker of ACR and suggest their potential functional roles.

Global trend in exosome isolation and application: an update concept in management of diseases

Extracellular vesicles (EVs) secreted by various cells offer great potential for use in the diagnosis and treatment of disease. EVs are heterogeneous membranous vesicles. Exosomes are a subtype of EVs, 40-150 nm spherical vesicles with a lipid layer derived from endosomes. Exosomes, which are involved in signal transduction and maintain homeostasis, are released from almost all cells, tissues, and body fluids. Although several methods exist to isolate and characterize EVs and exosomes, each technique has significant drawbacks and limitations that prevent progress in the field. New approaches in the biology of EVs show great potential for isolating and characterizing EVs, which will help us better understand their biological function. The strengths and limitations of conventional strategies and novel methods (microfluidic) for EV isolation are outlined in this review. We also present various exosome isolation techniques and kits that are commercially available and assess the global market demand for exosome assays.

Understanding exosomes: Part 2-Emerging leaders in regenerative medicine

Exosomes are the smallest subset of extracellular signaling vesicles secreted by most cells with the ability to communicate with other tissues and cell types over long distances. Their use in regenerative medicine has gained tremendous momentum recently due to their ability to be utilized as therapeutic options for a wide array of diseases/conditions. Over 5000 publications are currently being published yearly on this topic, and this number is only expected to dramatically increase as novel therapeutic strategies continue to be developed. Today exosomes have been applied in numerous contexts including neurodegenerative disorders (Alzheimer's disease, central nervous system, depression, multiple sclerosis, Parkinson's disease, post-traumatic stress disorders, traumatic brain injury, peripheral nerve injury), damaged organs (heart, kidney, liver, stroke, myocardial infarctions, myocardial infarctions, ovaries), degenerative processes (atherosclerosis, diabetes, hematology disorders, musculoskeletal degeneration, osteoradionecrosis, respiratory disease), infectious diseases (COVID-19, hepatitis), regenerative procedures (antiaging, bone regeneration, cartilage/joint regeneration, osteoarthritis, cutaneous wounds, dental regeneration, dermatology/skin regeneration, erectile dysfunction, hair regrowth, intervertebral disc repair, spinal cord injury, vascular regeneration), and cancer therapy (breast, colorectal, gastric cancer and osteosarcomas), immune function (allergy, autoimmune disorders, immune regulation, inflammatory diseases, lupus, rheumatoid arthritis). This scoping review is a first of its kind aimed at summarizing the extensive regenerative potential of exosomes over a broad range of diseases and disorders.

Role of dendritic cell‑derived exosomes in allergic rhinitis (Review)

Allergic rhinitis (AR) is a common pathological condition in otorhinolaryngology. Its prevalence has been increasing worldwide and is becoming a major burden to the world population. Dendritic cells (DCs) are typically activated and matured after capturing, phagocytosing, and processing allergens during the immunopathogenesis of AR. In addition, the process of DC activation and maturation is accompanied by the production of exosomes, which are cell‑derived extracellular vesicles (EVs) that can carry proteins, lipids, nucleic acids, and other cargoes involved in intercellular communication and material transfer. In particular, DC‑derived exosomes (Dex) can participate in allergic immune responses, where the biological substances carried by them can have potentially important implications for both the pathogenesis and treatment of AR. Dex can also be exploited to carry anti‑allergy agents to effectively treat AR. This provides a novel method to explore the pathogenesis of and treatment strategies for AR further. Therefore, the present review focuses on the origin, composition, function, and biological characteristics of DCs, exosomes, and Dex, in addition to the possible relationship between Dex and AR.

Application of exosomes as nanocarriers in cancer therapy

Cancer remains the most common lethal disease in the world. Although the treatment choices for cancer are still limited, significant progress has been made over the past few years. By improving targeted drug therapy, drug delivery systems promoted the therapeutic effects of anti-cancer medications. Exosome is a kind of natural nanoscale delivery system with natural substance transport properties, good biocompatibility, and high tumor targeting, which shows great potential in drug carriers, thereby providing novel strategies for cancer therapy. In this review, we present the formation, distribution, and characteristics of exosomes. Besides, extraction and isolation techniques are discussed. We focus on the recent progress and application of exosomes in cancer therapy in four aspects: exosome-mediated gene therapy, chemotherapy, photothermal therapy, and combination therapy. The current challenges and future developments of exosome-mediated cancer therapy are also discussed. Finally, the latest advances in the application of exosomes as drug delivery carriers in cancer therapy are summarized, which provide practical value and guidance for the development of cancer therapy.

microRNAs-based diagnostic and therapeutic applications in liver fibrosis

Liver fibrosis is a process of over-extracellular matrix (ECM) aggregation and angiogenesis, which develops into cirrhosis and hepatocellular carcinoma (HCC). With the increasing pressure of liver fibrosis, new therapeutics to cure this disease requires much attention. Exosome-cargoed microRNAs (miRNAs) are emerging approaches in the precision of the liver fibrotic paradigm. In this review, we outlined the different types of hepatic cells derived miRNAs that drive intra-/extra-cellular interactive communication in liver fibrosis with different physiological and pathological processes. Specifically, we highlighted the possible mechanism of liver fibrosis pathogenesis associated with immune response and angiogenesis. In addition, potential clinical biomarkers and different stem cell transplant-derived miRNAs-based therapeutic strategies in liver fibrosis were summarized in this review. miRNAs-based approaches might help researchers devise new candidates for the cell-free treatment of liver fibrosis. This article is categorized under: RNA in Disease and Development > RNA in Disease.

Extracellular vesicle-mediated regulation of macrophage polarization in bacterial infections

Extracellular vesicles (EVs) are nanoscale membrane-enveloped vesicles secreted by prokaryotic and eukaryotic cells, which are commonly defined as membrane vesicles (MVs) and exosomes, respectively. They play critical roles in the bacteria-bacteria and bacteria-host interactions. In infectious diseases caused by bacteria, as the first line of defense against pathogens, the macrophage polarization mode commonly determines the success or failure of the host's response to pathogen aggression. M1-type macrophages secrete pro-inflammatory factors that support microbicidal activity, while alternative M2-type macrophages secrete anti-inflammatory factors that perform an antimicrobial immune response but partially allow pathogens to replicate and survive intracellularly. Membrane vesicles (MVs) released from bacteria as a distinctive secretion system can carry various components, including bacterial effectors, nucleic acids, or lipids to modulate macrophage polarization in host-pathogen interaction. Similar to MVs, bacteria-infected macrophages can secrete exosomes containing a variety of components to manipulate the phenotypic polarization of "bystander" macrophages nearby or long distance to differentiate into type M1 or M2 to regulate the course of inflammation. Exosomes can also repair tissue damage associated with the infection by upregulating the levels of anti-inflammatory factors, downregulating the pro-inflammatory factors, and regulating cellular biological behaviors. The study of the mechanisms by which EVs modulate macrophage polarization has opened new frontiers in delineating the molecular machinery involved in bacterial pathogenesis and challenges in providing new strategies for diagnosis and therapy.

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

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

Regulation of Extracellular Vesicle-Mediated Immune Responses against Antigen-Specific Presentation

Extracellular vesicles (EVs) produced by various immune cells, including B and T cells, macrophages, dendritic cells (DCs), natural killer (NK) cells, and mast cells, mediate intercellular communication and have attracted much attention owing to the novel delivery system of molecules in vivo. DCs are among the most active exosome-secreting cells of the immune system. EVs produced by cancer cells contain cancer antigens; therefore, the development of vaccine therapy that does not require the identification of cancer antigens using cancer-cell-derived EVs may have significant clinical implications. In this review, we summarise the molecular mechanisms underlying EV-based immune responses and their therapeutic effects on tumour vaccination.

Effects of Exosomal Viral Components on the Tumor Microenvironment

Simple Summary

Oncogenic viral infection may lead to cancers, such as nasopharyngeal carcinoma, hepatocellular carcinoma, and cervical cancer. In addition to the tumor cells themselves, the tumor microenvironment also plays a decisive role in tumor evolution. Oncogenic viruses can affect the tumor microenvironment via exosomes influencing the occurrence and development of tumors by encapsulating and transporting viral components. This review focuses on the effects of virus-infected cancer exosomes on tumor microenvironment and tumor progression.

Abstract

Exosomes are extracellular membrane vesicles with a diameter of 30–100 nm, produced by different eukaryotic cells that contain multitudinous lipids, nucleic acids, and proteins. They transfer membrane components and nucleic acids between cells, thereby performing an information exchange between cells. Many studies have shown that a variety of tumor-associated viruses can exert their biological functions through exosomes. The tumor microenvironment (TME) is very important in the occurrence, development, and chemoresistance of tumors. It is composed of tumor cells, fibroblasts, endothelial cells, immune cells, stromal cells, and acellular components, such as exosomes and cytokines. This review focuses on the effects of virus-related components secreted by tumor cells over the TME in several virus-associated cancers.

A New Target of Dental Pulp-Derived Stem Cell-Based Therapy on Recipient Bone Marrow Niche in Systemic Lupus Erythematosus

Recent advances in mesenchymal stem/stromal cell (MSC) research have led us to consider the feasibility of MSC-based therapy for various diseases. Human dental pulp-derived MSCs (hDPSCs) have been identified in the dental pulp tissue of deciduous and permanent teeth, and they exhibit properties with self-renewal and in vitro multipotency. Interestingly, hDPSCs exhibit superior immunosuppressive functions toward immune cells, especially T lymphocytes, both in vitro and in vivo. Recently, hDPSCs have been shown to have potent immunomodulatory functions in treating systemic lupus erythematosus (SLE) in the SLE MRL/lpr mouse model. However, the mechanisms underlying the immunosuppressive efficacy of hDPSCs remain unknown. This review aims to introduce a new target of hDPSC-based therapy on the recipient niche function in SLE.