Cellular nanovesicles for therapeutic immunomodulation: A perspective on engineering strategies and new advances

NK cellular derived nanovesicles in tumor immunity

Natural Killer (NK) cells are a vital element of the innate immune system, and NK cell-based therapies have demonstrated efficacy against various malignancies. However, targeting solid tumors has been challenging due to the low infiltration of NK cells into tumors and the effective evasion strategies employed by tumors. Recent studies have shown that NK cell derived nanovesicles (NK-NV) can not only replicate the functions of NK cells but also offer more advantages in clinical applications. They are capable of transporting various cellular components such as proteins, nucleic acids, and lipids across distances, thereby facilitating intercellular communication among various cells within the tumor microenvironment (TME). With the progress in nanomedical technology, these vesicles can be engineered to carry a range of functional elements and therapeutic agents to enhance their antitumoral capabilities. In this review, we summarize the current available literature on NK-NVs, discuss their potential biological functions and the role of non-coding RNAs (ncRNAs), and explore their application in the treatment of solid tumors.

Exosomes in Systemic Autoimmune Diseases: Recent Advances in Diagnostic Biomarkers and Therapeutic Applications

Systemic autoimmune diseases (SADs) encompass a spectrum of organ involvement, clinical heterogeneity, and therapeutic challenges meriting significant research. These conditions involve the immune system mistakenly attacking and damaging multiple body tissues and organs, leading to chronic inflammation and damage. Exosomes are nanoscale extracellular vesicles secreted by cells that modulate intercellular communication and immunity. Accumulating evidence indicates that exosomes have multifaceted roles in the pathogenesis of SADs through processes like cellular signaling, immune modulation, antigen presentation, and inflammatory response. The cargo of exosomes, such as proteins, miRNAs, and lipids, are vital determinants of cellular and humoral immunity. This review examines key signaling pathways in four common SADs, rheumatoid arthritis, systemic lupus erythematosus, systemic sclerosis, and Sjögren's syndrome, and explores exosome as non-invasive biomarkers for diagnosis, disease monitoring, and therapeutic response prediction. Additionally, the therapeutic potential of mesenchymal stromal cells (MSCs) or various type of mesenchymal stem cells derived exosomes as cell-free immunotherapies for SADs is highlighted. Engineered exosomes, with enhanced targeting, bioavailability, low toxicity, are emerging as promising drug delivery vehicles. However, challenges such as high production costs, technical complexity, and inefficiency, along with the lack of standardized protocols, limit clinical implementation in SADs. A deeper understanding of exosome roles in SADs pathogenesis and innovative immunotherapies may provide valuable theoretical support for the diagnosis and treatment of these challenging conditions.

坏死性凋亡在糖尿病性创面愈合中的研究进展

糖尿病是一种目前临床上常见的慢性代谢性疾病，并发症多，尤其是糖尿病足可导致患者残疾，甚至死亡，具有易诊断、治疗难、治疗周期长、医疗费用高且容易复发等特点，严重影响患者的生活质量及身心健康，给个人、家庭和社会造成了沉重的负担。因此，如何提高糖尿病性创面的治愈率已成为急需解决的难题。坏死性凋亡是近年来发现的一种新型的细胞程序性死亡途径，可参与多种炎症反应。研究表明，细胞坏死性凋亡参与糖尿病的发病过程，在糖尿病性创面愈合中扮演着极其重要的作用。本文通过阐述细胞坏死性凋亡与创面相关蛋白的研究及其在糖尿病性创面中的作用机制，为临床治疗糖尿病性创面提供借鉴。

Inhalable nanovesicles loaded with a STING agonist enhance CAR-T cell activity against solid tumors in the lung

Suppression of chimeric antigen receptor-modified T (CAR-T) cells by the immunosuppressive tumor microenvironment remains a major barrier to their efficacy against solid tumors. To address this, we develop an anti-PD-L1-expressing nanovesicle loaded with the STING agonist cGAMP (aPD-L1 NVs@cGAMP) to remodel the tumor microenvironment and thereby enhance CAR-T cell activity. Following pulmonary delivery, the nanovesicles rapidly accumulate in the lung and selectively deliver STING agonists to PD-L1-overexpressing cells via the PD-1/PD-L1 interaction. This targeted delivery effectively avoids the systemic inflammation and poor cellular uptake that plague free STING agonists. Internalized STING agonists trigger STING signaling and induce interferon responses, which diminish immunosuppressive cell populations such as myeloid-derived suppressor cells in the tumor microenvironment and promote CAR-T cell infiltration. Importantly, the anti-PD-L1 single chain variable fragment on the nanovesicle surface blocks PD-L1 upregulation induced by STING agonists and prevents CAR-T cell exhaustion. In both orthotopic lung cancer and lung metastasis model, combined therapy with CAR-T cells and aPD-L1 NVs@cGAMP potently inhibits tumor growth and prevents recurrence. Therefore, aPD-L1 NVs@cGAMP is expected to serve as an effective CAR-T cell enhancer to improve the efficacy of CAR-T cells against solid tumors.

Concurrent immune checkpoint blockade for enhanced cancer immunotherapy utilizing engineered hybrid nanovesicles

Immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment, demonstrating unprecedented efficacy against advanced cancers. However, their clinical applications are significantly hampered by low overall response rates. Dual blockade of two immune checkpoints represents a promising strategy to enhance immunotherapeutic efficacy. In this study, we developed hybrid cell membrane nanovesicles adorned with PD-1 and SIRPα receptors for combination immunotherapy in melanoma. Our hybrid nanovesicles (PD-1/SIRPα NVs) demonstrated high specificity to PD-L1 and CD47 ligands, facilitating the phagocytosis of melanoma cells by macrophages. In a melanoma mouse model, PD-1/SIRPα NVs significantly suppressed 77% of tumor growth and elicited a robust antitumor immune response for immunotherapy. In conclusion, our findings highlight the promising potential of PD-1/SIRPα NVs as novel and effective ICIs for cancer immunotherapy.

Biomimetic Nanoparticles for Basic Drug Delivery

Biomimetic nanoparticles (BMNPs) are innovative nanovehicles that replicate the properties of naturally occurring extracellular vesicles, facilitating highly efficient drug delivery across biological barriers to target organs and tissues while ensuring maximal biocompatibility and minimal-to-no toxicity. BMNPs can be utilized for the delivery of therapeutic payloads and for imparting novel properties to other nanotechnologies based on organic and inorganic materials. The application of specifically modified biological membranes for coating organic and inorganic nanoparticles has the potential to enhance their therapeutic efficacy and biocompatibility, presenting a promising pathway for the advancement of drug delivery technologies. This manuscript is grounded in the fundamentals of biomimetic technologies, offering a comprehensive overview and analytical perspective on the preparation and functionalization of BMNPs, which include cell membrane-coated nanoparticles (CMCNPs), artificial cell-derived vesicles (ACDVs), and fully synthetic vesicles (fSVs). This review examines both "top-down" and "bottom-up" approaches for nanoparticle preparation, with a particular focus on techniques such as cell membrane coating, cargo loading, and microfluidic fabrication. Additionally, it addresses the technological challenges and potential solutions associated with the large-scale production and clinical application of BMNPs and related technologies.

M1-polarized macrophage-derived cellular nanovesicle-coated lipid nanoparticles for enhanced cancer treatment through hybridization of gene therapy and cancer immunotherapy

Optimum genetic delivery for modulating target genes to diseased tissue is a major obstacle for profitable gene therapy. Lipid nanoparticles (LNPs), considered a prospective vehicle for nucleic acid delivery, have demonstrated efficacy in human use during the COVID-19 pandemic. This study introduces a novel biomaterial-based platform, M1-polarized macrophage-derived cellular nanovesicle-coated LNPs (M1-C-LNPs), specifically engineered for a combined gene-immunotherapy approach against solid tumor. The dual-function system of M1-C-LNPs encapsulates Bcl2-targeting siRNA within LNPs and immune-modulating cytokines within M1 macrophage-derived cellular nanovesicles (M1-NVs), effectively facilitating apoptosis in cancer cells without impacting T and NK cells, which activate the intratumoral immune response to promote granule-mediating killing for solid tumor eradication. Enhanced retention within tumor was observed upon intratumoral administration of M1-C-LNPs, owing to the presence of adhesion molecules on M1-NVs, thereby contributing to superior tumor growth inhibition. These findings represent a promising strategy for the development of targeted and effective nanoparticle-based cancer genetic-immunotherapy, with significant implications for advancing biomaterial use in cancer therapeutics.

The novel insights of epithelial-derived exosomes in various fibrotic diseases

The characteristics of fibrosis include the abnormal accumulation of extracellular matrix proteins and abnormal tissue repair caused by injury, infection, and inflammation, leading to a significant increase in organ failure and mortality. Effective and precise treatments are urgently needed to halt and reverse the progression of fibrotic diseases. Exosomes are tiny vesicles derived from endosomes, spanning from 40 to 160 nanometers in diameter, which are expelled into the extracellular matrix environment by various cell types. They play a crucial role in facilitating cell-to-cell communication by transporting a variety of cargoes, including proteins, RNA, and DNA. Epithelial cells serve as the primary barrier against diverse external stimuli that precipitate fibrotic diseases. Numerous research suggests that exosomes from epithelial cells have a significant impact on several fibrotic diseases. An in-depth comprehension of the cellular and molecular mechanisms of epithelial cell-derived exosomes in fibrosis holds promise for advancing the exploration of novel diagnostic biomarkers and clinical drug targets. In this review, we expand upon the pathogenic mechanisms of epithelium-derived exosomes and highlight their role in the fibrotic process by inducing inflammation and activating fibroblasts. In addition, we are particularly interested in the bioactive molecules carried by epithelial-derived exosomes and their potential value in the diagnosis and treatment of fibrosis and delineate the clinical utility of exosomes as an emerging therapeutic modality, highlighting their potential application in addressing various medical conditions.

Dendritic cell-derived exosome (DEX) therapy for digestive system cancers: Recent advances and future prospect

Tumor-mediated immunosuppression is a fundamental obstacle to the development of dendritic cell (DC)-based cancer vaccines, which despite their ability to stimulate host anti-tumor CD8 T cell immunity, have not been able to generate meaningful therapeutic responses. Exosomes are inactive membrane vesicles that are nanoscale in size and are produced by the endocytic pathway. They are essential for intercellular communication. Additionally, DC-derived exosomes (DEXs) contained MHC class I/II (MHCI/II), which is frequently complexed with antigens and co-stimulatory molecules and is therefore able to prime CD4 and CD8 T cells that are specific to particular antigens. Indeed, vaccines with DEXs have been shown to exhibit better anti-tumor efficacy in eradicating tumors compared to DC vaccines in pre-clinical models of digestive system tumors. Also, there is room for improvement in the tumor antigenic peptide (TAA) selection process. DCs release highly targeted exosomes when the right antigenic peptide is chosen, which could aid in the creation of DEX-based antitumor vaccines that elicit more targeted immune responses. Coupled with their resistance to tumor immunosuppression, DEXs-based cancer vaccines have been heralded as the superior alternative cell-free therapeutic vaccines over DC vaccines to treat digestive system tumors. In this review, current studies of DEXs cancer vaccines as well as potential future directions will be deliberated.

Platelet-derived drug delivery systems: Pioneering treatment for cancer, cardiovascular diseases, infectious diseases, and beyond

Platelets play a critical role as circulating cells in the human body and contribute to essential physiological processes such as blood clotting, hemostasis, vascular repair, and thrombus formation. Currently, platelets are extensively employed in the development of innovative biomimetic drug delivery systems, offering significant enhancements in circulation time, biocompatibility, and targeted delivery efficiency compared to conventional drug delivery approaches. Leveraging the unique physiological functions of platelets, these platelet-derived drug delivery systems (DDSs) hold great promise for the treatment of diverse diseases, including cancer, cardiovascular diseases, infectious diseases, wound healing and other diseases. This review primarily focuses on the design and characteristics of existing platelet-derived DDSs, including their preparation and characterization methods. Furthermore, this review comprehensively outlines the applications of these materials across various diseases, offering a holistic understanding of their therapeutic potential. This study aimed to provide a comprehensive overview of the potential value of these materials in clinical treatment, serving as a valuable reference for the advancement of novel platelet-derived DDSs and their broader utilization in the field of disease treatment.

Immune cell-derived extracellular vesicles for precision therapy of inflammatory-related diseases

Inflammation-related diseases impose a significant global health burden, necessitating urgent exploration of novel treatment modalities for improved clinical outcomes. We begin by discussing the limitations of conventional approaches and underscore the pivotal involvement of immune cells in the inflammatory process. Amidst the rapid growth of immunology, the therapeutic potential of immune cell-derived extracellular vesicles (EVs) has garnered substantial attention due to their capacity to modulate inflammatory response. We provide an in-depth examination of immune cell-derived EVs, delineating their promising roles across diverse disease conditions in both preclinical and clinical settings. Additionally, to direct the development of the next-generation drug delivery systems, we comprehensively investigate the engineered EVs on their advanced isolation methods, cargo loading techniques, and innovative engineering strategies. This review ends with a focus on the prevailing challenges and considerations regarding the clinical translation of EVs in future, emphasizing the need of standardized characterization and scalable production processes. Ultimately, immune cell-derived EVs represent a cutting-edge therapeutic approach and delivery platform, holding immense promise in precision medicine.

T-cell immunity against senescence: potential role and perspectives

The development of age-associated diseases is related to the accumulation of senescent cells in the body. These are old non-functional cells with impaired metabolism, which are unable to divide. Such cells are also resistant to programmed cell death and prone to spontaneous production of some inflammatory factors. The accumulation of senescent cells is related to the age-associated dysfunction of organs and tissues as well as chronic inflammation that enhances with age. In the young organism, senescent cells are removed with the innate immunity system. However, the efficiency of this process decreases with age. Nowadays, more and more evidences are accumulating to support the involvement of specific immunity and T-lymphocytes in the fight against senescent cells. It has great physiological importance since the efficient elimination of senescent cells requires a high diversity of antigen-recognizing receptors to cover the entire spectrum of senescent-associated antigens with high precision and specificity. Developing the approaches of T-cell immunity stimulation to generate or amplify a physiological immune response against senescent cells can provide new perspectives to extend active longevity. In this mini-review, the authors summarize the current understanding of the role of T-cell immunity in the fight against senescent cells and discuss the prospects of stimulating adaptive immunity for combating the accumulation of senescent cells that occurs with age.

Dendritic Nanomedicine with Boronate Bonds for Augmented Chemo-Immunotherapy via Synergistic Modulation of Tumor Immune Microenvironment

Unsatisfied tumor accumulation of chemotherapeutic drugs and a complicated immunosuppressive microenvironment diminish the immune response rate and the therapeutic effect. Surface modification of these drugs with target ligands can promote their cellular internalization, but the modified drugs may be subjected to unexpected immune recognition and clearance. Herein, a phenylboronic acid (PBA) group-shieldable dendritic nanomedicine that integrates an immunogenic cell death (ICD)-inducing agent (epirubicin, Epi) and an indoleamine 2,3-dioxgenase 1 (IDO1) inhibitor (NLG919) is reported for tumor chemo-immunotherapy. This NLG919-loaded Epi-conjugated PEGylated dendrimers bridged with boronate bonds (NLG919@Epi-DBP) maintains a stable nanostructure during circulation. Under a moderate acidic condition, the PBA group exposes to the sialic acid residue on the tumor cell membrane to enhance the internalization and penetration of NLG919@Epi-DBP. At pH 5.0, NLG919@Epi-DBP rapidly disassembles to release the incorporated Epi and NLG919. Epi triggers robust ICD of tumor cells that evokes strong immune response. In addition, inhibition of the IDO1 activity downregulates the metabolism of L-tryptophan to kynurenine, leading to a reduction in the recruitment of immunosuppressive cells and modulation of the tumor immune microenvironment. Collectively, this promising strategy has been demonstrated to evoke robust immune response as well as remodel the immunosuppressive microenvironment for an enhanced chemo-immunotherapeutic effect.

Cellular-Membrane-Derived Vesicles for Cancer Immunotherapy

The medical community is constantly searching for new and innovative ways to treat cancer, and cellular-membrane-derived artificial vesicles are emerging as a promising avenue for cancer immunotherapy. These vesicles, which are derived from mammal and bacteria cell membranes, offer a range of benefits, including compatibility with living organisms, minimal immune response, and prolonged circulation. By modifying their surface, manipulating their genes, combining them with other substances, stimulating them externally, and even enclosing drugs within them, cellular vesicles have the potential to be a powerful tool in fighting cancer. The ability to merge drugs with diverse compositions and functionalities in a localized area is particularly exciting, as it offers a way to combine different immunotherapy treatments for maximum impact. This review contains information on the various sources of these vesicles and discusses some recent developments in cancer immunotherapy using this promising technology. While there are still obstacles to overcome, the possibilities for cellular vesicles in cancer treatment are truly exciting.

Exosomes as a potential therapeutic approach in osteoimmunology

Exosomes are natural extracellular vesicles that play a key role in inter- and intracellular communication. Currently they are considered as a promising therapeutic strategy for the treatment of various diseases. In osteoimmunology, exosomes can serve as biomarkers of bone homeostasis disorders and, at the same time, promising therapeutic agents with high stability in the biological environment, low immunogenicity and good bioavailability. In this review, we attempted to examine exosomes as natural mediators of intercellular communication, playing an essential role in the interaction of the immune system and bone tissue, based on an analysis of the PubMed database up to October 2023.

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.

Exosome nanovesicles as potential biomarkers and immune checkpoint signaling modulators in lung cancer microenvironment: recent advances and emerging concepts

Lung cancer remains the leading cause of cancer-related deaths globally, and the survival rate remains low despite advances in diagnosis and treatment. The progression of lung cancer is a multifaceted and dynamic phenomenon that encompasses interplays among cancerous cells and their microenvironment, which incorporates immune cells. Exosomes, which are small membrane-bound vesicles, are released by numerous cell types in normal and stressful situations to allow communication between cells. Tumor-derived exosomes (TEXs) possess diverse neo-antigens and cargoes such as proteins, RNA, and DNA and have a unique molecular makeup reflecting tumor genetic complexity. TEXs contain both immunosuppressive and immunostimulatory factors and may play a role in immunomodulation by influencing innate and adaptive immune components. Moreover, they transmit signals that contribute to the progression of lung cancer by promoting metastasis, epithelial-mesenchymal transition (EMT), angiogenesis, and immunosuppression. This makes them a valuable resource for investigating the immune environment of tumors, which could pave the way for the development of non-invasive biomarkers that could aid in the prognosis, diagnosis, and immunotherapy of lung cancer. While immune checkpoint inhibitor (ICI) immunotherapy has shown promising results in treating initial-stage cancers, most patients eventually develop adaptive resistance over time. Emerging evidence demonstrates that TEXs could serve as a prognostic biomarker for immunotherapeutic response and have a significant impact on both systemic immune suppression and tumor advancement. Therefore, understanding TEXs and their role in lung cancer tumorigenesis and their response to immunotherapies is an exciting research area and needs further investigation. This review highlights the role of TEXs as key contributors to the advancement of lung cancer and their clinical significance in lung immune-oncology, including their possible use as biomarkers for monitoring disease progression and prognosis, as well as emerging shreds of evidence regarding the possibility of using exosomes as targets to improve lung cancer therapy.

Dendritic Cell-Derived Exosomes in Cancer Immunotherapy

Exosomes are nanoscale vesicles released by diverse types of cells for complex intercellular communication. Numerous studies have shown that exosomes can regulate the body's immune response to tumor cells and interfere with the tumor microenvironment (TME). In clinical trials on dendritic cell (DC)-based antitumor vaccines, no satisfactory results have been achieved. However, recent studies suggested that DC-derived exosomes (DEXs) may be superior to DC-based antitumor vaccines in avoiding tumor cell-mediated immunosuppression. DEXs contain multiple DC-derived surface markers that capture tumor-associated antigens (TAAs) and promote immune cell-dependent tumor rejection. These findings indicate the necessity of the further development and improvement of DEX-based cell-free vaccines to complement chemotherapy, radiotherapy, and other immunotherapies. In this review, we highlighted the recent progress of DEXs in cancer immunotherapy, particularly by concentrating on landmark studies and the biological characterization of DEXs, and we summarized their important role in the tumor immune microenvironment (TIME) and clinical application in targeted cancer immunotherapy. This review could enhance comprehension of advances in cancer immunotherapy and contribute to the elucidation of how DEXs regulate the TIME, thereby providing a reference for utilizing DEX-based vaccines in clinical practice.

Extracellular vesicles and their cells of origin: Open issues in autoimmune diseases

The conventional therapeutic approaches to treat autoimmune diseases through suppressing the immune system, such as steroidal and non-steroidal anti-inflammatory drugs, are not adequately practical. Moreover, these regimens are associated with considerable complications. Designing tolerogenic therapeutic strategies based on stem cells, immune cells, and their extracellular vesicles (EVs) seems to open a promising path to managing autoimmune diseases' vast burden. Mesenchymal stem/stromal cells (MSCs), dendritic cells, and regulatory T cells (Tregs) are the main cell types applied to restore a tolerogenic immune status; MSCs play a more beneficial role due to their amenable properties and extensive cross-talks with different immune cells. With existing concerns about the employment of cells, new cell-free therapeutic paradigms, such as EV-based therapies, are gaining attention in this field. Additionally, EVs' unique properties have made them to be known as smart immunomodulators and are considered as a potential substitute for cell therapy. This review provides an overview of the advantages and disadvantages of cell-based and EV-based methods for treating autoimmune diseases. The study also presents an outlook on the future of EVs to be implemented in clinics for autoimmune patients.