Microfluidic-based exosome isolation and highly sensitive aptamer exosome membrane protein detection for lung cancer diagnosis

Highly sensitive and portable detection of PD-L1+ exosomes using a smartphone-assisted colorimetric sensor

PD-L1+ exosomes act as a useful biomarker in early cancer diagnosis, therapeutic monitoring, prognostic assessment, and immunotherapy for non-invasive liquid biopsy. There exists urgent clinical need for developing rapid, portable, and cost-effective immediate-response assays for PD-L1+ exosomes. Here, we proposed a smartphone-assisted colorimetric sensor using the triple-helix molecular switch (THMS) combined with Y-shaped catalytic hairpin assembly (Y-CHA) reaction. Namely, this strategy initiates the Y-CHA cycle and forms Y-DNA G-quadruplex/Hemin DNAzyme with K+ and Hemin after specific recognition of PD-L1+ exosomes by THMS. Then, PD-L1+ exosomes could be quantified via the oxidation of 3,3',5,5'-tetramethylbenzidine (TMB)-mediated color change. The method demonstrates excellent specificity and sensitivity, with a limit of detection (LOD) of 5.45 × 103 particles/mL and an LOD of 8.56 × 103 particles/mL using smartphone analysis. With this strategy, we found that PD-L1+ exosome levels were significantly elevated in the peripheral blood of patients with colorectal cancer liver metastases (CRLM), indicating great potential for identifying CRLM patients. Additionally, this colorimetric sensor can be used to quantify PD-L1+ exosomes across wide range of cancers, which possess a great prospect in the point-of-care testing filed for cancer companion diagnosis.

A microfluidic system for rapid enrichment and sensitive detection of E. coli based on bilayer membrane and high flux droplets

Rapid and sensitive detection of Escherichia coli (E. coli) is crucial for ensuring water safety. Traditional culture-based detection technologies are time-consuming, cumbersome, and difficult to meet immediate needs, while existing instrument-based detection is costly, time-consuming, and struggle to process complex samples. Herein, a microfluidic system for rapid enrichment and sensitive detection of E. coli in water based on bilayer membrane and high flux droplets is proposed. The bilayer membrane structure can enrich bacteria while removing impurities in the sample. High-throughput droplets can encapsulate single bacteria for enzymatic reactions within the droplets, reducing the reaction system to nanoliter, and greatly shortening the reaction time. The results showed that the detection of E. coli solution with different concentrations by this system had little difference compared to the plate counting method, demonstrating a good linear relationship (R = 0.9968) and the detection of total coliform in sewage has an accuracy rate of at least 80 %. In summary, this system combines enrichment technology with microdroplet technology to detect E. coli for the first time. It can achieve 50-fold enrichment of E. coli in water and bacteria isolation in 100 μL solution with tens of thousands of droplets, which greatly improves the sensitivity and efficiency of detection, thus showing great potential for ensuring water safety.

Extracellular Vesicles: Hermes between cancers and lymph nodes

Cancer is one of the main causes of death and a major obstacle to increasing life expectancy in all countries of the world. Lymph node metastasis (LNM) of in cancer patients indicates poor prognosis and it is an important indication to determine the therapeutic regime. Therefore, more attention should be given to the molecular mechanics of tumor lymphangiogenesis and LNM. Extracellular vesicles (EVs) are nanoscale cargo-bearing membrane vesicles that can serve as key mediators for the intercellular communication. Like Hermes, the messenger of the Greek gods, EVs can be secreted by tumor cells to regulate the LNM process. Many evidence has proved the clinical correlation between EVs and LNM in various cancer types. EVs plays an active role in the process of metastasis by expressing its connotative molecules, including proteins, nucleic acids, and metabolites. However, the clear role of EVs in the process of cancer LNM has not been thoroughly studied yet. In this review, we will summarize the clinical and mechanical findings of EVs regulating role on cancer LNM, and discuss the advanced modification of the research proposal. We propose the "PUMP" principle of EVs in LNM, including Preparation, Unleash, Migration, and Planting.

Si Microanemones Integrated Microfluidic Chip for Highly Efficient Isolation of Extracellular Vesicles

Liquid biopsy has emerged as a transformative approach for early cancer detection and treatment monitoring, offering significant potential to improve patient outcomes. However, isolating tumor-derived extracellular vesicles (EVs) from body fluids is often impeded by background noise, making subsequent analysis challenging. Herein, a bio-inspired 3D silicon microanemone (SMA) microfluidic chip is reported. This innovative structure is prepared by a two-step lithographic method combined with nanosphere lithography, achieving an impressive isolation efficiency of 89.4%. Simulation results reveal that the hierarchical structure not only provides more antibody binding sites but also synergizes with an integrated chaotic mixer to amplify fluid perturbations, while inducing a flow around circular cylinder phenomenon to enhance EV-antibody interactions. Finally, the SMA chip's performance is assessed with clinical samples and combined with RT-qPCR-based β-actin (ACTB) mRNA quantification in purified EVs. The results demonstrate its high sensitivity and specificity in isolating cancer-related EV subgroups, enabling non-invasive and precise detection of cancer biomarkers in blood samples.

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

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

Advancements and innovations in liquid biopsy through microfluidic technology for cancer diagnosis

Cancer is one of the leading causes of death worldwide, with approximately 10 million deaths and almost 20 million cases diagnosed in 2022. Various diagnostic methods for cancer, including physical examination, lab tests, imaging, and biopsy (tissue or liquid), are available in clinical settings. Liquid biopsy earned considerable attention due to its minimal invasiveness, patient convenience, and rapidness. Liquid biopsy is experiencing a significant transformation owing to the incorporation of microfluidic technologies. Microfluidic technologies allow for real-time observations and precise, sensitive, and efficient results in early cancer diagnosis through the identification of various biomarkers using body fluids at the microscale. This review highlights the transition from conventional cancer diagnostic methods to critically analyzing innovations and the integration of modern microfluidic technologies, presenting their influence in improving cancer diagnosis. This review highlights the significance of identifying exosomes and their biological components, such as micro RNAs, circular RNA, and mRNA, via microfluidics as biomarkers for cancer diagnosis. It also highlights the integration of microfluidics with advanced technologies, such as CRISPR gene editing, organ-on-a-chip models, 3D bioprinting, and nanotechnology, for cancer diagnosis. Moreover, integrating artificial intelligence into microfluidic systems has significantly transformed research related to cancer diagnosis. This advancement enables more precise diagnosis and personalized treatment strategies using the large available data on networks along with algorithmic approaches. Collectively, microfluidics and their integration into advanced technologies have shown the potential for progress in early cancer diagnosis and the customization of treatment approaches, such as immunotherapy, in the future.

Aptamer-based microfluidics for the detection of cancer biomarkers

Early diagnosis of cancer is a major concern in clinical medicine. Recently, aptamer-based microfluidics have offered promising platforms for the sensitive detection of cancer biomarkers. This review summarizes the application of aptamer sensors in the microfluidic platform for cancer biomarker analysis. The materials for microfluidic aptamer biosensor fabrication, unique design based on microposts, materials for enhanced detection capability, and the application principle of combining with other detection methods are introduced in detail, so as to demonstrate its development potential in cancer diagnosis and personalized therapy. Finally, the challenges and opportunities for developing miniaturized diagnostic platforms are discussed.

The Application of Stem Cells and Exosomes in Promoting Nerve Conduits for Peripheral Nerve Repair

The repair of peripheral nerve injury (PNI) presents a multifaceted and protracted challenge, with current therapeutic approaches failing to achieve optimal repair outcomes, thereby not satisfying the considerable clinical demand. The advent of tissue engineering has led to a growing body of experimental evidence indicating that the synergistic application of nerve conduits, which provide structural guidance, alongside the biological signals derived from exosomes and stem cells, yields superior therapeutic results for PNI compared to isolated interventions. This combined approach holds great promise for clinical application. In this review, we present the latest advancements in the treatment of PNI through the integration of stem cells or exosomes with nerve conduits. We have addressed the inadequate efficiency of exosomes or stem cells in conjunction with nerve conduits from 3 perspectives: enhancing stem cells or exosomes, improving nerve conduits, and incorporating physical stimulation.

Enhancing Analysis of Extracellular Vesicles by Microfluidics

Extracellular vesicles (EVs) play crucial roles in intercellular communication and hold great promise as biomarkers for noninvasive disease diagnosis. Intensive research efforts have been devoted to discovering the EV subpopulations responsible for specific functions or with enhanced effectiveness as disease markers, through extensive EV purification and content analysis. However, their high heterogeneity in size and cargo composition poses significant challenges for reaching such goals. Isolation methods like ultracentrifugation and size-exclusion chromatography, as well as content analysis approaches like polymerase chain reaction and enzyme-linked immunosorbent assay, have made significant contributions to improving our understanding of EV biology. Nonetheless, these methods face limitations in isolation efficiency, EV purity, and detection sensitivity and specificity due to issues like large sample consumption, unsatisfactory purity, and insufficient resolution in EV subtyping. Microfluidic technology presents promising solutions to these challenges, leveraging their intrinsic capabilities in precise flow and external energy field manipulation, sample compartmentalization, and signal enhancement at the micro- and nanoscale. Hence, this review summarizes the recent developments in microfluidics-enabled EV analysis, paying special attention to the unique microfluidic features exploited. Strategies such as viscoelastic and inertial flow, fluid mixing, and external-field-assisted approaches in improving EV purification, as well as compartmentalization and micro/nanostructures for enhancing EV detection, are examined. Furthermore, the current limitations and potential future directions are discussed to inspire advancements in this rapidly developing field.

On-Chip Isolation and Reciprocal Signal Amplification Detection of Tumor-Derived Exosomes in Dual-Control Microfluidic Device

The detection of exosomes is critical for health monitoring and disease diagnosis. However, their small size and low concentration present significant challenges. In this study, we designed a dual-control microchip integrated with a surface-enhanced Raman scattering (SERS) signal amplification detection method. By employing separate chambers for isolation and detection, this method achieves magnetic separation control and DNA cascade signal amplification with electrokinetic enrichment detection. The magnetic separation step captures and isolates exosomes in a magnetic-controlled reaction chamber, releasing a signal-switching strand that translates exosome recognition into a DNA signal amplification process. The DNA cascade reciprocal signal amplification reaction is performed in an electrokinetic enrichment reaction chamber, significantly improving detection efficiency and signal intensity. In addition, absolute-value coupled data processing reduces background interference. These unique merits enable precise and highly efficient assay of exosomes. This dual-control microchip signal amplification sensor exhibits remarkable sensitivity, rapid detection times, with a detection limit of 10.9 particles/μL and a reaction time of 35 min, and successful application to real sample analysis. The platform offers a viable, accurate, and portable solution for medical point-of-care testing.

Chitosan-exosome synergy: Advanced cell-free scaffold approaches for bone tissue engineering

Bone regeneration and repair, which are hampered by fractures, bone diseases, and trauma, require innovative therapeutic strategies in the field of regenerative medicine. Conventional treatments, such as the use of autologous and allogeneic bone grafts and metal implants, are the primary modalities for bone augmentation in clinical practice; however, they exhibit various limitations. To overcome these limitations, new paradigms, such as exosome-based therapies using chitosan scaffolds, exhibit significant potential for bone tissue engineering. Exosomes, which serve as cell-free therapeutic agents, promote immunomodulation, angiogenesis, and osteogenesis. Moreover, the distinct structural and functional properties of chitosan facilitate efficient exosome loading and sustained release, exerting localized and prolonged regenerative effects crucial for bone repair. Advanced scaffold modification and exosome mimetic integration are other innovative strategies to promote osteogenesis and vascularized bone regeneration. Focusing on these novel approaches, this review highlights chitosan-exosome scaffolds as transformative platforms for bone tissue engineering, providing new avenues for effective and targeted bone regeneration and repair.

Immunofluorescent analysis of exosomes using a microchip filled with transparent antibody-conjugated beads for breast cancer liquid biopsy

BACKGROUND

Exosomes represent optimal biomarkers for liquid biopsy. Current exosome-based methods are still limited by isolation methods, long processing times, complex structure, low accuracy, large sample volume consumption, and the influence of chemical reagents on the analysis results.

RESULT

To overcome these challenges, a novel microfluidic approach that employs continuous, rapid, and efficient processes is proposed for the capture and enriching exosomes using the optical transparent antibody-conjugated microbeads within the chip. By interfering with laminar flow, increasing mass transfer efficiency, expanding the specific reaction area, and concentrating the fluorescent signal, the microbeads raise the sensitivity of the detection. Furthermore, multiple biomarkers of a single disease could be detected simultaneously by multi-color labeling with a single sample injection. This method required only 50 μL of plasma sample for detection within 35 min, demonstrating a low detection limit of 2.61 × 103 exosomes/μL, coupled with high reproducibility, stability, and specificity. We evaluated the diagnostic potential for breast cancer (BC) by analyzing plasma exosomes in samples from 15 patients with BC and 15 healthy individuals. The identification of total exosomes, EpCAM-positive exosomes, and MUC1-positive exosomes demonstrated a strong ability to distinguish between cancer patients and healthy individuals, as indicated by area under curve (AUC) values of 0.88, 0.98, and 0.99, respectively. The integrated multi-biomarker detection strategy achieved the highest of diagnostic accuracy and specificity (SUM, AUC = 1.0).

SIGNIFICANCE

This study presents a novel exosome-based liquid biopsy strategy, which is expected to enhance the accuracy and efficiency of early diagnosis for cancer and other diseases.

A Surface-Enhanced Raman Scattering Platform for Rapid, Sensitive, and Cost-Effective Quantitative Analysis of Exosomes Based on Titanium Dioxide Functionalized Nanomaterials

Exosomes have emerged as vital biomarkers for cancer diagnosis because they carry diverse biomolecules, reflecting the physiological state of their original cells. However, despite this potential, there are still challenges in developing highly sensitive, rapid, and efficient detection methods in clinical diagnosis. Here, we present a straightforward approach for the efficient enrichment and SERS quantification of exosomes via the interaction between titanium dioxide (TiO2) and the phospholipid bilayer on the exosome membrane. First, Fe3O4@TiO2 was employed for rapid exosome enrichment, enabling magnetic separation from biological fluids. Subsequently, surface-enhanced Raman scattering (SERS) tags, Ag@NTP@TiO2, were applied to label exosomes for precise quantification. Ag@NTP@TiO2 exhibited strong and homogeneous SERS signals. The TiO2 shell of SERS tags not only facilitated the labeling of exosomes rapidly but also ensured the long-term stability of the SERS signals. It avoided the high cost and time-consuming disadvantages of the traditional method of recognizing exosomes with antibodies and aptamers. Our approach enabled quantitative detection of exosomes from capture to SERS measurement within 10 min. The quantification range spanned 5 orders of magnitude, with the detection limit as low as 640 particles/mL. In clinical plasma sample testing, this method exhibited good diagnosis ability in distinguishing cancer patients from healthy individuals, with an area under the curve (AUC) of 0.880. All these results suggest that our method may become a powerful tool for liquid biopsy based on the analysis of exosomes in clinics.

Biomedical implication of microfluidics in disease diagnosis and therapeutics: from fabrication to prognosis

Microfluidics has given us an approach to regulate the fluids' behaviour and influence at the microscale level, including the microchannels as an integral element. Microchannels encompass the high surface area-to-volume ratio, causing the rapid diffusion and mixing of substances within the tiny canals and facilitating predictable and stable fluid dynamics. This precise regulatory mechanism of fluid behaviour by microchannels is significant for several biological and chemical processes. In the present scenario, microfluidics plays a significant role in pharmaceutical industries for efficient drug synthesis, DNA analysis, protein crystallization and cell culture. They have also been exploited in fabricating site-directed drug delivery systems such as microchannels. This review has illustrated the different strategies for fabricating microfluidic devices (e.g. microchannels) and their potential implications in biomedical sciences. It also includes a discussion about the challenges associated with standardisation, cost-effective production, biocompatibility and safety concerning microchannel fabrication and its biological application, as well as possible approaches to overcome these issues. These microfluidic devices have the potential for diagnosis, drug delivery, disease monitoring and other applications in human health and diseases and require more attention from researchers to fabricate them precisely and efficiently.

Current advances and future prospects of blood-based techniques for identifying benign and malignant pulmonary nodules

Lung cancer is the leading cause of cancer-related mortality worldwide, highlighting the urgent need for more accurate and minimally invasive diagnostic tools to improve early detection and patient outcomes. While low-dose computed tomography (LDCT) is effective for screening in high-risk individuals, its high false-positive rate necessitates more precise diagnostic strategies. Liquid biopsy, particularly ctDNA methylation analysis, represents a promising alternative for non-invasive classification of indeterminate pulmonary nodules (IPNs). This review highlights the progress and clinical potential of liquid biopsy technologies, including traditional proteins markers, cfDNA, exosomes, metabolomics, circulating tumor cells (CTCs) and platelets, in lung cancer diagnosis. We discuss the integration of ctDNA methylation analysis with traditional imaging and clinical data to enhance the early detection of IPNs, as well as potential solutions to address the challenges of low biomarker concentration and background noise. By advancing precision diagnostics, liquid biopsy technologies could transform lung cancer management, improve survival rates, and reduce the disease burden.

Aptamer selection via versatile microfluidic platforms and their diverse applications

Aptamers are synthetic oligonucleotides that bind with high affinity and specificity to various targets, making them invaluable for diagnostics, therapeutics, and biosensing. Microfluidic platforms can improve the efficiency and scalability of aptamer selection, especially through advancements in systematic evolution of ligands by exponential enrichment (SELEX) methods. Microfluidic SELEX methods are less time-consuming and labor-intensive and include critical steps like library preparation, binding, partitioning, and amplification. This review examines the contributions of microfluidic technology to SELEX-based aptamer identification, with alternative methods like conditional SELEX, in vivo-like SELEX and Non-SELEX for selecting aptamers and also discusses critical SELEX steps over the past decade. This work also examined the integrated microfluidic systems for SELEX, highlighting innovations such as conditional SELEX and in vivo-like SELEX. These advancements provide potential solutions to existing challenges in aptamer selection using conventional SELEX, especially concerning biological samples. A trend toward non-SELEX methods was also reviewed and discussed, wherein nucleic acid amplification was eliminated to improve aptamer selection. Microfluidic platforms have demonstrated versatility not only in aptamer selection but also in various detection applications; they allow for precise control of liquid flow and have been essential in the advancement of therapeutic aptamers, facilitating accurate screening, enhancing drug delivery systems, and enabling targeted therapeutic interventions. Although advances in microfluidic technology are expected to enhance aptamer-based diagnostics, therapeutics, and biosensing, challenges still persist, especially in up-scaling microfluidic systems for various clinical applications. The advantages and limitations of integrating microfluidic platforms with aptamer development are further addressed, emphasizing areas for future research. We also present a perspective on the future of microfluidic systems and aptamer technologies, highlighting their increasing significance in healthcare and diagnostics.

Regulatory Roles of Exosomes in Aging and Aging-Related Diseases

Exosomes are small vesicles with diameters ranging from 30 to 150 nm. They originate from cellular endocytic systems. These vesicles contain a rich payload of biomolecules, including proteins, nucleic acids, lipids, and metabolic products. Exosomes mediate intercellular communication and are key regulators of a diverse array of biological processes, such as oxidative stress and chronic inflammation. Furthermore, exosomes have been implicated in the pathogenesis of infectious diseases, autoimmune disorders, and cancer. Aging is closely associated with the onset and progression of numerous diseases and is significantly influenced by exosomes. Recent studies have consistently highlighted the important functions of exosomes in the regulation of cellular senescence. Additionally, research has explored their potential to delay aging, such as the alleviatory effects of stem cell-derived exosomes on the aging process, which offers broad potential for the development and application of exosomes as anti-aging therapeutic strategies. This review aims to comprehensively investigate the multifaceted impact of exosomes while concurrently evaluating their potential applications and underscoring their strategic significance in advancing anti-aging strategies.

Extracellular vesicles in tumor immunity: mechanisms and novel insights

Extracellular vesicles (EVs), nanoscale vesicles secreted by cells, have attracted considerable attention in recent years due to their role in tumor immunomodulation. These vesicles facilitate intercellular communication by transporting proteins, nucleic acids, and other biologically active substances, and they exhibit a dual role in tumor development and immune evasion mechanisms. Specifically, EVs can assist tumor cells in evading immune surveillance and attack by impairing immune cell function or modulating immunosuppressive pathways, thereby promoting tumor progression and metastasis. Conversely, they can also transport and release immunomodulatory factors that stimulate the activation and regulation of the immune system, enhancing the body's capacity to combat malignant diseases. This dual functionality of EVs presents promising avenues and targets for tumor immunotherapy. By examining the biological characteristics of EVs and their influence on tumor immunity, novel therapeutic strategies can be developed to improve the efficacy and relevance of cancer treatment. This review delineates the complex role of EVs in tumor immunomodulation and explores their potential implications for cancer therapeutic approaches, aiming to establish a theoretical foundation and provide practical insights for the advancement of future EVs-based cancer immunotherapy strategies.

Methods for Eluting Intact Extracellular Vesicles From Aptamer-Based Affinity Chromatography: A Critical Evaluation Based on Downstream Applications

Extracellular vesicles (EVs) are nanosized vesicles released by cells, containing molecular cargo such as proteins and nucleic acids. EVs offer promising avenues for the detection of biomarkers of disease and are excellent candidates for drug delivery and therapeutics. Although EVs can be obtained from biological fluids, it is challenging to obtain intact EVs from complex fluids and there is no universally accepted standard method of isolating EVs. When affinity chromatography-based isolation is used to isolate EVs from complex biofluids, there exist multiple ways to elute intact EVs from capture. This review aims to identify effective EV elution methods for preserving EV integrity and bioactivity after capture on aptamer-functionalized substrates, addressing the requirements of various downstream applications. We hypothesize that when used for elution, different materials and techniques influence the characteristics of EVs, such as their molecular content and bioactivity. The elution reagent and technique must be selected for the intended application for isolated EVs. However, currently, there is no agreement on the optimal elution method for EVs. This literature review aims to evaluate the different methods used to elute intact EVs from capture with regards to the downstream applications of isolated EVs. Based on the results of our analysis of recent literatures, the two elution reagents that are optimal for general purposes of the eluted intact EVs are deoxyribonuclease I and complementary oligonucleotides, as they both preserve EV characteristics that are required for molecular analysis and bioactivity, such as maintained morphology and protein profiles.

An Advanced Multivalent Ligand-Decorated Microsphere Enrichment System Efficiently Captures Circulating Tumor Cells In Vivo

Capturing circulating tumor cells (CTCs) in vivo from the bloodstream lessens tumor metastasis and recurrence risks. However, the absence of CTC receptors due to epithelial-mesenchymal transition (EMT), the limited binding capacity of a single ligand, and the complexity of the blood flow environment significantly reduce the efficiency of CTC capture in vivo. Herein, a multivalent ligand-decorated microsphere enrichment system (MLMES) is crafted that incorporates a capture column replete with an immunosorbent that precisely recognizes and binds the stably expressed cluster of differentiation 44 (CD44) and glucose transporter protein 1 (GLUT1) receptors present on the exterior of CTCs. As peripheral blood flows through the column, CTCs are efficiently captured, achieving an in vivo capture rate of up to 64.2%, the highest reported to date. Moreover, the MLMES demonstrates excellent biocompatibility, broad-spectrum tumor cells capture, and storage stability. Importantly, it significantly eliminates a substantial quantity of CTCs from peripheral blood, reducing the risk of metastasis. This breakthrough method has broad clinical application potential in preventing tumor metastasis and recurrence, bringing new possibilities for improving cancer treatment.

Exosomes as a Therapeutic Strategy in Cancer: Potential Roles as Drug Carriers and Immune Modulators

Exosome-based cancer immunotherapy is advancing quickly on the concept of artificially activating the immune system to combat cancer. They can mechanistically change the tumor microenvironment, increase immune responses, and function as efficient drug delivery vehicles because of their inherent bioactivity, low toxicity, and immunogenicity. Accurate identification of the mechanisms of action of exosomes in tumor environments, along with optimization of their isolation, purification, and characterization methods, is necessary to increase clinical applications. Exosomes can be modified through cargo loading and surface modification to enhance their therapeutic applications, either before or after the donor cells' isolation. These engineered exosomes can directly target tumor cells at the tumor site or indirectly activate innate and adaptive immune responses in the tumor microenvironment. This approach is particularly effective when combined with traditional cancer immunotherapy techniques such as vaccines, immune checkpoints, and CAR-T cells. It can improve anti-tumor responses, induce long-term immunity, and address the limitations of traditional therapies, such as poor penetration in solid tumors and immunosuppressive environments. This review aims to provide a comprehensive and detailed overview of the direct role of engineered exosomes as drug delivery systems and their immunomodulatory effects on tumors as an indirect approach to fighting cancer. Additionally, it will discuss novel immunotherapy options.

Recent Advances in Aptamer-Based Microfluidic Biosensors for the Isolation, Signal Amplification and Detection of Exosomes

Exosomes carry diverse tumor-associated molecular information that can reflect real-time tumor progression, making them a promising tool for liquid biopsy. However, traditional methods for exosome isolation and detection often rely on large, expensive equipment and are time-consuming, limiting their practical applicability in clinical settings. Microfluidic technology offers a versatile platform for exosome analysis, with advantages such as seamless integration, portability and reduced sample volumes. Aptamers, which are single-stranded oligonucleotides with high affinity and specificity for target molecules, have been frequently employed in the development of aptamer-based microfluidics for the isolation, signal amplification, and quantitative detection of exosomes. This review summarizes recent advances in aptamer-based microfluidic strategies for exosome analysis, including (1) strategies for on-chip exosome capture mediated by aptamers combined with nanomaterials or nanointerfaces; (2) aptamer-based on-chip signal amplification techniques, such as enzyme-free hybridization chain reaction (HCR), rolling circle amplification (RCA), and DNA machine-assisted amplification; and (3) various aptamer-assisted detection methods, such as fluorescence, electrochemistry, surface-enhanced Raman scattering (SERS), and magnetism. The limitations and advantages of these methods are also summarized. Finally, future challenges and directions for the clinical analysis of exosomes based on aptamer-based microfluidics are discussed.

Exosomes in Oral Diseases: Mechanisms and Therapeutic Applications

Exosomes, small extracellular vesicles secreted by various cells, play crucial roles in the pathogenesis and treatment of oral diseases. Recent studies have highlighted their involvement in orthodontics, periodontitis, oral squamous cell carcinoma (OSCC), and hand, foot, and mouth disease (HFMD). Exosomes have a positive effect on the inflammatory environment of the oral cavity, remodeling and regeneration of oral tissues, and offer promising therapeutic options for bone and periodontal tissue restoration. In OSCC tumor-derived exosomes promote cancer progression through cell proliferation, migration, invasion, and angiogenesis, and serve as potential biomarkers for early diagnosis and prognosis. Additionally, engineered exosomes constructed specifically based on exosome properties hold great promise for targeted drug delivery and regenerative therapies such as bone regeneration in orthodontics and periodontal healing. With continued research, exosomes hold great potential for improving diagnosis and treatment in oral diseases, advancing personalized and regenerative therapies.

Exosomes in Autoimmune Diseases: A Review of Mechanisms and Diagnostic Applications

Exosomes, small extracellular vesicles secreted by various cell types, have emerged as key players in the pathophysiology of autoimmune diseases. These vesicles serve as mediators of intercellular communication, facilitating the transfer of bioactive molecules such as proteins, lipids, and nucleotide. In autoimmune diseases, exosomes have been implicated in modulating immune responses, oxidative stress, autophagy, gut microbes, and the cell cycle, contributing to disease initiation, progression, and immune dysregulation. Recent advancements in exosome isolation techniques and their molecular characterization have paved the way for exploring their clinical potential as biomarkers and therapeutic targets. This review focuses on the mechanisms by which exosomes influence autoimmune disease development and their potential clinical applications, particularly in diagnosis. The role of exosomes in autoimmune diseases, including systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), type 1 diabetes mellitus (T1DM), inflammatory bowel disease (IBD), and Sjögren's syndrome (SS), is discussed in relation to their involvements in antigen presentation, T-cell activation, and the induction of inflammatory pathways. Additionally, exosome-based biomarkers offer promising non-invasive diagnostic tools for early diagnostic, disease monitoring, and therapeutic response assessment. However, challenges such as standardization of exosome isolation protocols and validation of their clinical significance remain. This review highlights the potential of exosomes as both diagnostic biomarkers and therapeutic targets in autoimmune diseases, emphasizing the need for further research to overcome current limitations and fully harness their clinical value.

Exosomes in oral squamous cell carcinoma: functions, challenges, and potential applications

Oral squamous cell carcinoma (OSCC) accounts for approximately 90% of all oral cancers, significantly impacting the survival and quality of life of patients. Exosomes, small extracellular vesicles released by cells, play a crucial role in intercellular communication in cancer. Nevertheless, their function and mechanism in OSCC remain elusive. Search Pubmed, Web of Science, and Cochrane Library using keywords OSCC, exome, diagnosis, and treatment to review the research progress of exome in OSCC. Based on these results, this review starting from the biosynthesis, structure, and contents of exosomes, elaborates on the research progress of exosomes in the diagnosis and treatment of OSCC. It explores the potential of exosomes in the diagnosis and treatment of OSCC, and briefly describes the challenges researchers currently face.

Exosomal ncRNAs in liquid biopsies for lung cancer

Exosomal non-coding RNAs (ncRNAs) have become essential contributors to advancing and treating lung cancers (LCs). The development of liquid biopsies that utilize exosomal ncRNAs (exo-ncRNAs) offers an encouraging method for diagnosing, predicting, and treating LC. This thorough overview examines the dual function of exo-ncRNAs as both indicators for early diagnosis and avenues for LC treatment. Exosomes are tiny vesicles secreted by various cells, including cancerous cells, enabling connection between cells by delivering ncRNAs. These ncRNAs, which encompass circular RNAs, long ncRNAs, and microRNAs, participate in the modulation of gene expression and cellular functions. In LC, certain exo-ncRNAs are linked to tumour advancement, spread, and treatment resistance, positioning them as promising non-invasive indicators in liquid biopsies. Additionally, targeting these ncRNAs offers potential for innovative treatment approaches, whether by suppressing harmful ncRNAs or reinstating the activity of tumour-suppressing ones. This review emphasizes recent developments in the extraction and analysis of exo-ncRNAs, their practical applications in LC treatment, and the challenges and prospects for translating these discoveries into clinical usage. Through this detailed examination of the current state of the art, we aim to highlight the significant potential of exo-ncRNAs for LC diagnostics and treatments.

Advances of New Extracellular Vesicle Isolation and Detection Technologies in Cancer Diagnosis

Cancer is a global health issue threatening people's lives. Currently, cancer detection methods still have a lot of room for improvement in both efficiency and accuracy. The development and application of new technologies are urgently required for early cancer diagnosis and prognosis. Extracellular vesicles (EVs) are a type of phospholipid bilayer vesicle secreted by cells and play an important role in cancer development and metastasis. These small vesicles participate in cancer information transmission, antigen presentation, angiogenesis, immune response, tumor invasion, and mediate signaling pathways in the tumor microenvironment. Liquid biopsy of EV cargo contents is a fast-developing research area, holding promise for early cancer diagnosis and monitoring cancer progression in real-time. However, current EV detection technologies for clinical translation are still facing many challenges. Recent advancements in developing techniques for EV isolation and detection have made significant progress and are paving the way toward clinical application. Here, the advantages and limitations of traditional EV detection and isolation technologies in cancer diagnosis and prognosis are reviewed. The review also focuses on emerging EV detection and isolation technologies in cancer, discusses the challenges faced by current methods, and explores the perspective of new EV detection techniques for future cancer diagnosis.

Microfluidic biosensors for biomarker detection in body fluids: a key approach for early cancer diagnosis

Early detection of cancer significantly improves patient outcomes, with biomarkers offering a promising avenue for earlier and more precise diagnoses. Microfluidic biosensors have emerged as a powerful tool for detecting these biomarkers in body fluids, providing enhanced sensitivity, specificity, and rapid analysis. This review focuses on recent advances in microfluidic biosensors from 2018 to 2024, detailing their operational principles, fabrication techniques, and integration with nanotechnology for cancer biomarker detection. Additionally, we have reviewed recent innovations in several aspects of microfluidic biosensors, such as novel detection technologies, nanomaterials and novel microfluidic chip structures, which significantly enhance detection capabilities. We highlight key biomarkers pertinent to early cancer detection and explore how these innovations in biosensor technology contribute to the evolving landscape of personalized medicine. We further explore how these technologies could be incorporated into clinical cancer diagnostic workflows to improve early detection and treatment outcomes. These innovations could help enable more precise and personalized cancer diagnostics. In addition, this review addresses several important issues such as enhancing the scalability and sensitivity of these biosensors in clinical settings and points out future possibilities of combining artificial intelligence diagnostics with microfluidic biosensors to optimize their practical applications. This overview aims to guide future research and clinical applications by addressing current challenges and identifying opportunities for further development in the field of biomarker research.

Exosomal integrins in tumor progression, treatment and clinical prediction (Review)

Integrins are a large family of cell adhesion molecules involved in tumor cell differentiation, migration, proliferation and neovascularization. Tumor cell‑derived exosomes carry a large number of integrins, which are closely associated with tumor progression. As crucial mediators of intercellular communication, exosomal integrins have gained attention in the field of cancer biology. The present review examined the regulatory mechanisms of exosomal integrins in tumor cell proliferation, migration and invasion, and emphasized their notable roles in tumor initiation and progression. The potential of exosomal integrins as drug delivery systems in cancer treatment was explored. Additionally, the potential of exosomal integrins in clinical tumor prediction was considered, while summarizing their applications in diagnosis, prognosis assessment and treatment response prediction. Thus, the present review aimed to provide guidance and insights for future basic research and the clinical translation of exosomal integrins. The study of exosomal integrins is poised to offer new perspectives and methods for precise cancer treatment and clinical prediction.

Integrated SERS-Microfluidic Sensor Based on Nano-Micro Hierarchical Cactus-like Array Substrates for the Early Diagnosis of Prostate Cancer

The detection and analysis of cancer cell exosomes with high sensitivity and precision are pivotal for the early diagnosis and treatment strategies of prostate cancer. To this end, a microfluidic chip, equipped with a cactus-like array substrate (CAS) based on surface-enhanced Raman spectroscopy (SERS) was designed and fabricated for the detection of exosome concentrations in Lymph Node Carcinoma of the Prostate (LNCaP). Double layers of polystyrene (PS) microspheres were self-assembled onto a polyethylene terephthalate (PET) film to form an ordered cactus-like nanoarray for detection and analysis. By combining EpCAM aptamer-labeled SERS nanoprobes and a CD63 aptamer-labeled CAS, a 'sandwich' structure was formed and applied to the microfluidic chips, further enhancing the Raman scattering signal of Raman reporter molecules. The results indicate that the integrated microfluidic sensor exhibits a good linear response within the detection concentration range of 105 particles μL-1 to 1 particle μL-1. The detection limit of exosomes in cancer cells can reach 1 particle μL-1. Therefore, we believed that the CAS integrated microfluidic sensor offers a superior solution for the early diagnosis and therapeutic intervention of prostate cancer.

Advancements in Exosome Proteins for Breast Cancer Diagnosis and Detection: With a Focus on Nanotechnology

Breast cancer, a leading cause of mortality among women, has been recognized as requiring improved diagnostic methods. Exosome proteins, found in small extracellular vesicles, have emerged as a promising solution, reflecting the state of their cell of origin and playing key roles in cancer progression. This review examines their potential in breast cancer diagnosis, discussing advanced isolation and characterization techniques such as ultracentrifugation and microfluidic-based approaches. Various detection methods-including electrochemical, nano-based, optical, and machine learning platforms-were evaluated for their high sensitivity, specificity, and non-invasive capabilities. Electrochemical methods were used to identify unique protein signatures for rapid, cost-effective diagnosis, while machine learning enhanced the classification of exosome proteins. Nano-based techniques leveraged nanomaterials to detect low-abundance proteins, and optical methods offered real-time, label-free monitoring. Despite their promise, challenges in standardizing protocols and integrating these diagnostics into clinical practice remain. Future directions include technological advancements, personalized medicine, and exploring the therapeutic potential of exosome proteins.

Lung cancer exosomal Gal3BP promotes osteoclastogenesis with potential connotation in osteolytic metastasis

New insights into cellular interactions and key biomolecules involved in lung cancer (LC) bone metastasis could offer remarkable therapeutic benefits. Using a panel of four LC cells, we investigated LC-bone interaction by exposing differentiating osteoclasts (OCs) to LC cells (LC-OC interaction) directly in a co-culture setting or indirectly via treatment with LC secretomes (conditioned media or exosomes). LC-OC interaction facilitated the production of large-sized OCs (nuclei > 10) coupled with extensive bone resorption pits. Proteomic analysis of LC exosomes identified galectin-3-binding protein (Gal3bp) as a potential biomarker which was released primarily by most of LC-derived exosomes. The facilitation of OC differentiation and function by LC-exosomal Gal3bp was supported by the application of recombinant Gal3bp and anti-Gal3bp in OC treatment. Further, our results exhibited a dysregulation of crucial OC markers (TRAF6, p-SAPK/JNK, p-44/42 MAPK, NFAT2 and CD9) during LC-OC interaction that possibly contributed to the facilitation of osteoclastogenesis. Simulation of bone metastasis via intratibial injection of LC cells revealed Gal3bp's possible roles in enhancing OC activation leading to osseous tissue resorption. Overall, this work implicated LC-exosomal Gal3bp in osteolytic metastasis of LC which warrants further studies to assess its potential prognostic and therapeutic relevance.

MicroRNA-enriched exosome as dazzling dancer between cancer and immune cells

Exosomes are widely recognized for their roles in numerous biological processes and as intercellular communication mediators. Human cancerous and normal cells can both produce massive amounts of exosomes. They are extensively dispersed in tumor-modeling animals' pleural effusions, ascites, and plasma from people with cancer. Tumor cells interact with host cells by releasing exosomes, which allow them to interchange various biological components. Tumor growth, invasion, metastasis, and even tumorigenesis can all be facilitated by this delicate and complex system by modifying the nearby and remote surroundings. Due to the existence of significant levels of biomolecules like microRNA, exosomes can modulate the immune system's stimulation or repression, which in turn controls tumor growth. However, the role of microRNA in exosome-mediated communication between immunological and cancer cells is still poorly understood. This study aims to get the most recent information on the "yin and yang" of exosomal microRNA in the regulation of tumor immunity and immunotherapy, which will aid current cancer treatment and diagnostic techniques.

Bilateral efforts to improve SERS detection efficiency of exosomes by Au/Na7PMo11O39 Combined with Phospholipid Epitope Imprinting

Detection of cancer-related exosomes in body fluids has become a revolutionary strategy for early cancer diagnosis and prognosis prediction. We have developed a two-step targeting detection method, termed PS-MIPs-NELISA SERS, for rapid and highly sensitive exosomes detection. In the first step, a phospholipid polar site imprinting strategy was employed using magnetic PS-MIPs (phospholipids-molecularly imprinted polymers) to selectively isolate and enrich all exosomes from urine samples. In the second step, a nanozyme-linked immunosorbent assay (NELISA) technique was utilized. We constructed Au/Na7PMo11O39 nanoparticles (NPs) with both surface-enhanced Raman scattering (SERS) property and peroxidase catalytic activity, followed by the immobilization of CD9 antibodies on the surface of Au/Na7PMo11O39 NPs. The Au/Na7PMo11O39-CD9 antibody complexes were then used to recognize CD9 proteins on the surface of exosomes enriched by magnetic PS-MIPs. Lastly, the high sensitivity detection of exosomes was achieved indirectly via the SERS activity and peroxidase-like activity of Au/Na7PMo11O39 NPs. The quantity of exosomes in urine samples from pancreatic cancer patients obtained by the PS-MIPs-NELISA SERS technique showed a linear relationship with the SERS intensity in the range of 6.21 × 107-2.81 × 108 particles/mL, with a limit of detection (LOD) of 5.82 × 107 particles/mL. The SERS signal intensity of exosomes in urine samples from pancreatic cancer patients was higher than that of healthy volunteers. This bidirectional MIPs-NELISA-SERS approach enables noninvasive, highly sensitive, and rapid detection of cancer, facilitating the monitoring of disease progression during treatment and opening up a new avenue for rapid early cancer screening.

Lectin microarray based glycan profiling of exosomes for dynamic monitoring of colorectal cancer progression

BACKGROUND

Exosomes, as emerging biomarkers in liquid biopsies in recent years, offer profound insights into cancer diagnostics due to their unique molecular signatures. The glycosylation profiles of exosomes have emerged as potential biomarkers, offering a novel and less invasive method for cancer diagnosis and monitoring. Colorectal cancer (CRC) represents a substantial global health challenge and burden. Thus there is a great need for the aberrant glycosylation patterns on the surface of CRC cell-derived exosomes, proposing them as potential biomarkers for tumor characterization.

RESULTS

The interactions of 27 lectins with exosomes from three CRC cell lines (SW480, SW620, HCT116) and one normal colon epithelial cell line (NCM460) have been analyzed by the lectin microarray. The result indicates that Ulex Europaeus Agglutinin I (UEA-I) exhibits high affinity and specificity towards exosomes derived from SW480 cells. The expression of glycosylation related genes within cells has been analyzed by high-throughput quantitative polymerase chain reaction (HT-qPCR). The experimental result of HT-qPCR is consistent with that of lectin microarray. Moreover, the limit of detection (LOD) of UEA-I microarray is calculated to be as low as 2.7 × 105 extracellular vehicles (EVs) mL-1 (three times standard deviation (3σ) of blank sample). The UEA-I microarray has been successfully utilized to dynamically monitor the progression of tumors in mice-bearing SW480 CRC subtype, applicable in tumor sizes ranging from 2 mm to 20 mm in diameter.

SIGNIFICANCE

The results reveal that glycan expression pattern of exosome is linked to specific CRC subtypes, and regulated by glycosyltransferase and glycosidase genes of mother cells. Our findings illuminate the potential of glycosylation molecules on the surface of exosomes as reliable biomarkers for diagnosis of tumor at early stage and monitoring of cancer progression.

Circulating serum exosomes i-tRF-AspGTC and tRF-1-SerCGA as diagnostic indicators for non-small cell lung cancer

BACKGROUND

tRF-RNA-a representative of non-coding RNA (ncRNA)-is a precursor or fragment of mature tRNA and plays a crucial regulatory role in the occurrence and development of cancer. There is currently little research on tRF-RNA as a diagnostic marker in cancer, especially for NSCLC from serum exosomes.

METHOD

Serum exosomes were successfully extracted from serum; their physical morphology was captured by transmission electron microscopy (TEM); appropriate particle size detection was performed using qNano; surface labeling was verified through western blotting. Serum exosomes i-tRF-AspGTC and tRF-1-SerCGA were selected through gene microarray, and qPCR was used to validate their significance in 242 patients and 201 healthy individuals. The area under the curve (AUC) was used to evaluate the diagnostic indicators of non-small cell lung cancer (NSCLC).

RESULT

Compared with 201 healthy individuals, i-tRF-AspGTC and tRF-1-SerCGA were significantly downregulated in 242 NSCLC patients and 95 early-stage patients. For tRF-AspGTC and tRF-1-SerCGA, the predictive diagnostic efficiency rates of AUC were 0.690 and 0.680, respectively, whereas the early diagnostic efficiency rates were 0.656 and 0.688, respectively. The result of combined diagnosis with CEA and CYFRA21-1 was 0.928, and the early diagnostic efficiency was 0.843, which is a very high biological predictive factor for NSCLC.

CONCLUSION

The expression of serum exosomes i-tRF-AspGTC and tRF-1-SerCGA was significantly downregulated in NSCLC patients. These exosomes could be used as predictive indicators for diagnosis or early diagnosis of NSCLC.

Rapid isolation of extracellular vesicles using covalent organic frameworks combined with microfluidic technique

Extracellular vesicles (EVs) are nano-sized lipid-membrane vesicles involved in intercellular communication and reflecting the physiological and pathological processes of their parental cells. Rapid isolation of EVs with low cost is an essential precondition for downstream function exploration and clinical applications. In this work, we designed a novel EVs isolation device based on the boronated organic framework (BOF) coated recyclable microfluidic chip (named EVs-BD) to separate EVs from cell culture media. Using a reactive oxygen species responsive phenylboronic ester compound, the highly porous BOF with a pore size in the range of 10-300 nm was prepared by crosslinking γ-cyclodextrin metal-organic frameworks. A mussel-inspired polydopamine (PDA)/polyethyleneimine (PEI) coating was employed to pattern BOF on the PDMS substrate of microfluidic channels. The EVs-BD was demonstrated to offer distinct advantages over the traditional ultracentrifugation method, such as operation simplicity and safety, reduced time and expense, and low expertize requirements. All things considered, a novel approach of EV acquisition has been successfully developed, which can be customized easily to meet the requirements of various EV-relevant research.

Trends and frontiers in signal amplification for aptamer-based tumor detection: A bibliometric analysis

BACKGROUND

Malignant tumors are one of the leading causes of death worldwide, imposing a substantial economic and social burden. Early detection is the key to improving cure rates and reducing mortality rates, which requires the development of sensitive early detection technologies. Signal amplification techniques play a crucial role in aptamer-based early detection of tumors and are increasingly garnering attention from researchers.

AIM

To investigate the current research status, developmental trajectories, and hotspots in signal amplification for aptamer-based tumor detection through bibliometric analysis.

METHODS

English publications pertaining to signal amplification in aptamer-based tumor detection were retrieved from the Web of Science Core Collection database. VOSviewer and CiteSpace software were employed to analyze various information within this field, including countries, institutions, authors, co-cited authors, journals, co-cited journals, cited references, and keywords.

RESULTS

A total of 757 publications were included in this study. China accounted for 85.47% of all publications, with Nanjing University (China) emerging as the institution with the highest publication output. The most influential authors and journals were Hasanzadeh M. from Iran and "Biosensors and Bioelectronics", respectively. Exosomes and carcinoembryonic antigen (CEA) stood out as the most researched tumor-related molecules. Currently, the predominant signal amplification technique, nanomaterial, and signal transduction method were identified as hybridization chain reactions, gold nanoparticles, and electrochemical methods, respectively. Over the past 3 years, exosomes, CEA, electrochemical biosensors, and nanosheets have emerged as research hotspots, exhibiting a robust burst of intensity.

CONCLUSION

This study is the first bibliometric analysis of literature on signal amplification in aptamer-based tumor detection and elucidates the current status, hotspots, and prospective research directions within this realm. Additionally, it provides an important reference for researchers.

Current status and progress of PD-L1 detection: guiding immunotherapy for non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is the leading cause of cancer-related deaths and represents a substantial disease burden worldwide. Immune checkpoint inhibitors combined with chemotherapy are the standard first-line therapy for advanced NSCLC without driver mutations. Programmed death-ligand 1 (PD-L1) is currently the only approved immunotherapy marker. PD-L1 detection methods are diverse and have developed rapidly in recent years, such as improved immunohistochemical detection methods, the application of liquid biopsy in PD-L1 detection, genetic testing, radionuclide imaging, and the use of machine learning methods to construct PD-L1 prediction models. This review focuses on the detection methods and challenges of PD-L1 from different sources, and discusses the influencing factors of PD-L1 detection and the value of combined biomarkers. Provide support for clinical screening of immunotherapy-advantage groups and formulation of personalized treatment decisions.

A lateral flow assay strip for simultaneous detection of miRNA and exosomes in liver cancer

By employing an aptamer as the bridge and combining catalytic hairpin assembly with the Au aggregation amplification effect, a lateral flow assay (LFA) is designed for simultaneous detection of liver cancer-associated miRNA and exosomes. The LFA can differentiate between liver cancer patients and healthy individuals with simple operation and high accuracy.

Exosome theranostics: Comparative analysis of P body and exosome proteins and their mutations for clinical applications

Exosomes are lipid-bilayered vesicles, originating from early endosomes that capture cellular proteins and genetic materials to form multi-vesicular bodies. These exosomes are secreted into extracellular fluids such as cerebrospinal fluid, blood, urine, and cell culture supernatants. They play a key role in intercellular communication by carrying active molecules like lipids, cytokines, growth factors, metabolites, proteins, and RNAs. Recently, the potential of exosomal delivery for therapeutic purposes has been explored due to their low immunogenicity, nano-scale size, and ability to cross cellular barriers. This review comprehensively examines the biogenesis of exosomes, their isolation techniques, and their diverse applications in theranostics. We delve into the mechanisms and methods for loading exosomes with mRNA, miRNA, proteins, and drugs, highlighting their transformative role in delivering therapeutic payloads. Additionally, the utility of exosomes in stem cell therapy is discussed, showcasing their potential in regenerative medicine. Insights into exosome cargo using pre- or post-loading techniques are critical for exosome theranostics. We review exosome databases such as ExoCarta, Expedia, and ExoBCD, which document exosome cargo. From these databases, we identified 25 proteins common to both exosomes and P-bodies, known for mutations in the COSMIC database. Exosome databases do not integrate with mutation analysis programs; hence, we performed mutation analysis using additional databases. Accounting for the mutation status of parental cells and exosomal cargo is crucial in exosome theranostics. This review provides a comprehensive report on exosome databases, proteins common to exosomes and P-bodies, and their mutation analysis, along with the latest studies on exosome-engineered theranostics.

Empowering Exosomes with Aptamers for Precision Theranostics

As information messengers for cell-to-cell communication, exosomes, typically small membrane vesicles (30-150 nm), play an imperative role in the physiological and pathological processes of living systems. Accumulating studies have demonstrated that exosomes are potential biological candidates for theranostics, including liquid biopsy-based diagnosis and drug delivery. However, their clinical applications are hindered by several issues, especially their unspecific detection and insufficient targeting ability. How to upgrade the accuracy of exosome-based theranostics is being widely explored. Aptamers, benefitting from their admirable characteristics, are used as excellent molecular recognition elements to empower exosomes for precision theranostics. With high affinity against targets and easy site-specific modification, aptamers can be incorporated with platforms for the specific detection of exosomes, thus providing opportunities for advancing disease diagnostics. Furthermore, aptamers can be tailored and functionalized on exosomes to enable targeted therapeutics. Herein, this review emphasizes the empowering of exosomes by aptamers for precision theranostics. A brief introduction of exosomes and aptamers is provided, followed by a discussion of recent progress in aptamer-based exosome detection for disease diagnosis, and the emerging applications of aptamer-functionalized exosomes for targeted therapeutics. Finally, current challenges and opportunities in this research field are presented.

A proximity ligation hybridization triggered structure-switching based signal amplification strategy for sensitive and accurate exosome detection

Exosomes have significant functions in intercellular communication, as well as in tumor migration and invasion. Nevertheless, the precise identification of exosomes poses a significant obstacle due to their low abundance in biofluids and potential disruption caused by free protein molecules, such as CD63 protein. In this study, we have developed a signal amplification method for precise detection of exosomes using a proximity ligation hybridization triggered structure-switching approach. The method involves the dual-recognition of exosomes by two probes: an aptamer probe that recognizes the exosomal surface protein CD63 (L1 probe), and a cholesterol probe that targets the biolipid layer of the exosomes (L2 probe). Based on the dual-recognition of exosomes, we have successfully developed an accurate and sensitive approach that integrates the proximity ligation hybridization technique with a structure-switching based signal cycle. This approach allows for the simultaneous analysis of two biomarkers, enabling both quantification and tracing of exosomes without the need for enzymes. Eventually, the proposed method exhibits a wide detection range of 5 orders of magnitude and a low limit of detection of 36 particles per μL, making it suitable for a wide range of applications in the fields of biological science, biomedical engineering, and personalized medicine.

Macrophage-derived CD36 + exosome subpopulations as novel biomarkers of Candida albicans infection

Invasive candidiasis (IC) is a notable healthcare-associated fungal infection, characterized by high morbidity, mortality, and substantial treatment costs. Candida albicans emerges as a principal pathogen in this context. Recent academic advancements have shed light on the critical role of exosomes in key biological processes, such as immune responses and antigen presentation. This burgeoning body of research underscores the potential of exosomes in the realm of medical diagnostics and therapeutics, particularly in relation to fungal infections like IC. The exploration of exosomal functions in the pathophysiology of IC not only enhances our understanding of the disease but also opens new avenues for innovative therapeutic interventions. In this investigation, we focus on exosomes (Exos) secreted by macrophages, both uninfected and those infected with C. albicans. Our objective is to extract and analyze these exosomes, delving into the nuances of their protein compositions and subgroups. To achieve this, we employ an innovative technique known as Proximity Barcoding Assay (PBA). This methodology is pivotal in our quest to identify novel biological targets, which could significantly enhance the diagnostic and therapeutic approaches for C. albicans infection. The comparative analysis of exosomal contents from these two distinct cellular states promises to yield insightful data, potentially leading to breakthroughs in understanding and treating this invasive fungal infection. In our study, we analyzed differentially expressed proteins in exosomes from macrophages and C. albicans -infected macrophages, focusing on proteins such as ACE2, CD36, CAV1, LAMP2, CD27, and MPO. We also examined exosome subpopulations, finding a dominant expression of MPO in the most prevalent subgroup, and a distinct expression of CD36 in cluster14. These findings are crucial for understanding the host response to C. albicans and may inform targeted diagnostic and therapeutic approaches. Our study leads us to infer that MPO and CD36 proteins may play roles in the immune escape mechanisms of C. albicans. Additionally, the CD36 exosome subpopulations, identified through our analysis, could serve as potential biomarkers and therapeutic targets for C. albicans infection. This insight opens new avenues for understanding the infection's pathology and developing targeted treatments.

Ultrasensitive electrochemical sensor based on synergistic effect of Ag@MXene and antifouling cyclic multifunctional peptide for PD-L1 detection in serum

A sensing interface co-constructed from the two-dimensional conductive material (Ag@MXene) and an antifouling cyclic multifunctional peptide (CP) is described. While the large surface area of Ag@MXene loads more CP probes, CP binds to Ag@MXene to form a fouling barrier and ensure the structural rigidity of the targeting sequence. This strategy synergistically enhances the biosensor's sensitivity and resistance to contamination. The SPR results showed that the binding affinity of the CP to the target was 6.23 times higher than that of the antifouling straight-chain multifunctional peptide (SP) to the target. In the 10 mg/mL BSA electrochemical fouling test, the fouling resistance of Ag@MXene + CP (composite sensing interface of CP combined with Ag@MXene) was 30 times higher than that of the bare electrode. The designed electrochemical sensor exhibited good selectivity and wide dynamic response range at PD-L1 concentrations from 0.1 to 50 ng/mL. The lowest detection limit was 24.54 pg/mL (S/N = 3). Antifouling 2D materials with a substantial specific surface area, coupled with non-straight chain antifouling multifunctional peptides, offer a wide scope for investigating the sensitivity and antifouling properties of electrochemical sensors.

Dual-Aptamer Recognition of DNA Logic Gate Sensor-Based Specific Exosomal Proteins for Ovarian Cancer Diagnosis

Clinical diagnosis of ovarian cancer lacks high accuracy due to the weak selection of specific biomarkers along with the circumstance biomarkers localization. Clustering analysis of proteins transported on exosomes enables a more precise screening of effective biomarkers. Herein, through bioinformatics analysis of ovarian cancer and exosome proteomes, two coexpressed proteins, EpCAM and CD24, specifically enriched, were identified, together with the development of an as-derived dual-aptamer targeted exosome-based strategy for ovarian cancer screening. In brief, a DNA ternary polymer with aptamers targeting EpCAM and CD24 was designed to present a logic gate reaction upon recognizing ovarian cancer exosomes, triggering a rolling circle amplification chemiluminescent signal. A dynamic detection range of 6 orders of magnitude was achieved by quantifying exosomes. Moreover, for clinical samples, this strategy could accurately differentiate exosomes from healthy persons, other cancer patients, and ovarian cancer patients, enabling promising in situ detection. By accurately selecting biomarkers and constructing a dual-targeted exosomal protein detection strategy, the limitation of insufficient specificity of traditional protein markers was circumvented. This work contributed to the development of exosome-based prognosis monitoring in ovarian cancer through the identification of disease-specific exosome protein markers.

An integrated liposome-based microfluidic strategy for rapid colorimetric analysis: A case study of microRNA-21 detection

In this study, a novel integrated liposome-based microfluidic platform combined with a smartphone was designed for the rapid colorimetric detection of microRNA-21 (miRNA-21) in real samples. The flowing surface-functionalized liposomes were first captured by nucleic acid-functionalized Au nanoparticles in the microfluidic chip. In the presence of miRNA-21, the DNA strand modified on the surface of Au nanoparticles hybridized with the target to form double-stranded products and was cleaved by duplex-specific nuclease (DSN) enzyme, causing the liposomes to be re-released. Then, as the liposomes in the colorimetric module were lysed and the "cellular" contents were released, a step-by-step "glucose-glucose oxidase-3,3',5,5'-tetramethylbenzidine (TMB)" colorimetric reaction process catalyzed by the G-quadruplex/hemin was triggered. The grayscale values were recorded and recognized by the smartphone camera for miRNA-21 analysis. The advantages of the present strategy included the portability of smartphone-based colorimetric assay, the encapsulation and transport of reactants by liposomes and the low solvent usage of microfluidic chip. Under optimal conditions, this assay exhibited a wide linear range from 1 pM to 1 nM (r2 = 0.9981), and the limit of detection of miRNA-21 was as low as 0.27 pM. Moreover, the high specificity of this strategy allowed its successful application to the rapid analysis of miRNA-21 in real blood serum samples of people with type 2 diabetes.

Recent Advances in Microfluidic-Based Extracellular Vesicle Analysis

Extracellular vesicles (EVs) serve as vital messengers, facilitating communication between cells, and exhibit tremendous potential in the diagnosis and treatment of diseases. However, conventional EV isolation methods are labor-intensive, and they harvest EVs with low purity and compromised recovery. In addition, the drawbacks, such as the limited sensitivity and specificity of traditional EV analysis methods, hinder the application of EVs in clinical use. Therefore, it is urgent to develop effective and standardized methods for isolating and detecting EVs. Microfluidics technology is a powerful and rapidly developing technology that has been introduced as a potential solution for the above bottlenecks. It holds the advantages of high integration, short analysis time, and low consumption of samples and reagents. In this review, we summarize the traditional techniques alongside microfluidic-based methodologies for the isolation and detection of EVs. We emphasize the distinct advantages of microfluidic technology in enhancing the capture efficiency and precise targeting of extracellular vesicles (EVs). We also explore its analytical role in targeted detection. Furthermore, this review highlights the transformative impact of microfluidic technology on EV analysis, with the potential to achieve automated and high-throughput EV detection in clinical samples.

Exosomes as mediators of signal transmitters in biotoxins toxicity: a comprehensive review

Small membranes known as exosomes surround them and are released by several cell types both in vitro and in vivo. These membranes are packed with a variety of biomolecules, including proteins, lipids, deoxyribonucleic acid (DNA), ribonucleic acid (RNA), and non-coding RNA (ncRNA). As a source of biological nanomaterials, exosomes play a role in information and substance transmission between cells and have been identified as a general method of facilitating communication during interactions between the body, target organs, and toxins.. In order to understand the changes and mechanism of the composition and level of exosomes after biotoxin infection, this review focuses on current findings on the exosomes and highlights their novel uses in the toxicity mechanism. Exosomes are mainly used as a delivery carrier or mediated by receptors, and play an immune role after the toxin enters the body. This review expounds on the importance of exosomes in the toxicological mechanism of biotoxins and provides new insights for further diagnosis of toxic biomarkers, detoxification, and treatment development.

Exosomes: efficient macrophage-related immunomodulators in chronic lung diseases

Macrophages, the predominant immune cells in the lungs, play a pivotal role in maintaining the delicate balance of the pulmonary immune microenvironment. However, in chronic inflammatory lung diseases and lung cancer, macrophage phenotypes undergo distinct transitions, with M1-predominant macrophages promoting inflammatory damage and M2-predominant macrophages fostering cancer progression. Exosomes, as critical mediators of intercellular signaling and substance exchange, participate in pathological reshaping of macrophages during development of pulmonary inflammatory diseases and lung cancer. Specifically, in inflammatory lung diseases, exosomes promote the pro-inflammatory phenotype of macrophages, suppress the anti-inflammatory phenotype, and subsequently, exosomes released by reshaped macrophages further exacerbate inflammatory damage. In cancer, exosomes promote pro-tumor tumor-associated macrophages (TAMs); inhibit anti-tumor TAMs; and exosomes released by TAMs further enhance tumor proliferation, metastasis, and resistance to chemotherapy. Simultaneously, exosomes exhibit a dual role, holding the potential to transmit immune-modulating molecules and load therapeutic agents and offering prospects for restoring immune dysregulation in macrophages during chronic inflammatory lung diseases and lung cancer. In chronic inflammatory lung diseases, this is manifested by exosomes reshaping anti-inflammatory macrophages, inhibiting pro-inflammatory macrophages, and alleviating inflammatory damage post-reshaping. In lung cancer, exosomes reshape anti-tumor macrophages, inhibit pro-tumor macrophages, and reshaped macrophages secrete exosomes that suppress lung cancer development. Looking ahead, efficient and targeted exosome-based therapies may emerge as a promising direction for treatment of pulmonary diseases.