Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer, characterized by difficulties in early diagnosis, prone to distant metastasis, and high recurrence rates following surgery. Extracellular vesicles (EVs) are a class of cell-derived particles, including exosomes, characterized by a phospholipid bilayer. They serve as effective carriers for intercellular communication cargo, including proteins and nucleic acids, and are widely involved in tumor progression. They are being explored as potential tumor biomarkers and novel therapeutic avenues. We provide a brief overview of the biogenesis and characteristics of EVs to better understand their classification standards. The focus of this review is on the research progress of EV-associated proteins in the field of HCC. EV-associated proteins are involved in tumor growth and regulation in HCC, participate in intercellular communication within the tumor microenvironment (TME), and are implicated in events including angiogenesis and epithelial-mesenchymal transition (EMT) during tumor metastasis. In addition, EV-associated proteins show promising diagnostic efficacy for HCC. For the treatment of HCC, they also demonstrate significant potential including enhancing the efficacy of tumor vaccines, and as targeting cargo anchors. Facing current challenges, we propose the future directions of research in this field. Above all, research on EV-associated proteins offers the potential to enhance our comprehension of HCC and offer novel insights for developing new treatment strategies.

Rheumatoid arthritis (RA) remains a challenging chronic autoimmune disorder characterized by persistent joint inflammation and damage. While modern regenerative strategies, encompassing cell/stem cell-based therapies, gene therapy, and tissue engineering, have advanced tissue repair efforts, a definitive cure for RA remains elusive. Consequently, there is growing interest in developing targeted therapies that directly address the underlying mechanisms driving RA pathogenesis, such as extracellular vesicles (EVs). These small membrane-bound particles can modulate immune responses within the inflammatory microenvironment of damaged cartilage. To launch the clinical potential of EVs, they can be isolated from various cell types through several techniques. EVs can carry various bioactive molecules and anti-inflammatory or pro-regenerative drugs, deliver them directly to the affected joints, and affect the behavior of injured cells, making them a compelling choice for targeted therapy and drug delivery in RA patients. However, there are still several challenges and limitations associated with EV-based therapy, including the absence of standardized protocols for EV isolation, characterization, and delivery. This review provides a comprehensive overview of the cellular sources of EVs in RA and delves into their therapeutic potential and the hurdles they must overcome.

The restoration of cartilage injuries remains a formidable challenge in orthopedics, chiefly attributed to the absence of vascularization and innervation in cartilage. Decellularized extracellular matrix (dECM) derived from cartilage, following antigenic removal through decellularization processes, has exhibited remarkable biocompatibility and bioactivity, rendering it a viable candidate for cartilage repair. Additionally, extracellular vesicles (EVs) generated from cartilage have demonstrated a synergistic effect when combined with dECM, potentially mitigating the inhibitory impact on protein synthesis by phosphorylating 4ebp, thereby promoting the synthesis of cartilage-related proteins such as collagen. In pursuit of this objective, we have innovated a novel bioink and repair scaffold characterized by exceptional biocompatibility, bioactivity, and biodegradability, establishing a tissue-specific microenvironment conducive to chondrogenesis. Within rat osteochondral defects, the biologically active scaffold successfully prompted the formation of transparent cartilage, featuring adequate mechanical strength, favorable elasticity, and dECM deposition indicative of cartilage. In summary, this study has effectively engineered a hydrogel bioink tailored for cartilage repair and devised a bioactive cartilage repair scaffold proficient in instigating cell differentiation and fostering cartilage repair.

This study presents and compares two methods for identifying the types of extracellular vesicles (EVs) from different cell lines. Through SDS-PAGE analysis, we discovered that the ratio of CD63 to CD81 in different EVs is consistent and distinct, making it a reliable characteristic for recognizing EVs secreted by cancer cells. However, the electrophoresis and imaging processes may introduce errors in the concentration values, especially at lower concentrations, rendering this method potentially less effective. An alternative approach involves the use of quartz crystal microbalance (QCM) and electroanalytical interdigitated electrode (IDT) biosensors for EV type identification and quantification. The QCM frequency shift caused by EVs is directly proportional to their concentration, while electroanalysis relies on measuring the curvature of the I-V curve as a distinguishing feature, which is also proportional to EV concentration. Linear regression lines for the QCM frequency shift and the electroanalysis curvature of various EV types are plotted separately, enabling the estimation of the corresponding concentration for an unknown EV type on the graphs. By intersecting the results from both biosensors, the unknown EV type can be identified. The biosensor analysis method proves to be an effective means of analyzing both the type and concentration of EVs from different cell lines.

Brain tumors, and, in particular, glioblastoma (GBM), are among the most aggressive forms of cancer. In spite of the advancement in the available therapies, both diagnosis and treatments are still unable to ensure pathology-free survival of the GBM patients for more than 12-15 months. At the basis of the still poor ability to cope with brain tumors, we can consider: (i) intra-tumor heterogeneity; (ii) heterogeneity of the tumor properties when we compare different patients; (iii) the blood-brain barrier (BBB), which makes difficult both isolation of tumor-specific biomarkers and delivering of therapeutic drugs to the brain. Recently, it is becoming increasingly clear that cancer cells release large amounts of extracellular vesicles (EVs) that transport metabolites, proteins, different classes of RNAs, DNA, and lipids. These structures are involved in the pathological process and characterize any particular form of cancer. Moreover, EVs are able to cross the BBB in both directions. Starting from these observations, researchers are now evaluating the possibility to use EVs purified from organic fluids (first of all, blood and saliva), in order to obtain, through non-invasive methods (liquid biopsy), tumor biomarkers, and, perhaps, also for obtaining nanocarriers for the targeted delivering of drugs.

Conventional drug delivery techniques face challenges related to targeting and adverse reactions. Recent years have witnessed significant advancements in nanoparticle-based drug carriers. Nevertheless, concerns persist regarding their safety and insufficient metabolism. Employing cells and their derivatives, such as cell membranes and extracellular vesicles (EVs), as drug carriers effectively addresses the challenges associated with nanoparticle carriers. However, an essential hurdle remains in efficiently loading drugs into these carriers. With the advancement of microfluidic technology and its advantages in precise manipulation at the micro- and nanoscales, as well as minimal sample loss, it has found extensive application in the loading of drugs using cells and their derivatives, thereby fostering the development of drug-loading techniques. This paper outlines the characteristics and benefits of utilizing cells and their derivatives as drug carriers and provides an overview of current drug-loading techniques, particularly those rooted in microfluidic technology. The significant potential for microfluidic technology in targeted disease therapy through drug delivery systems employing cells and their derivatives, is foreseen.

Long coronavirus disease 2019 (COVID-19) is linked to an increased risk of post-acute sequelae affecting the pulmonary and extrapulmonary organ systems. Up to 20% of COVID-19 patients may proceed to a more serious form, such as severe pneumonia, acute respiratory distress syndrome (ARDS), or pulmonary fibrosis. Still, the majority of patients may only have mild, self-limiting sickness. Of particular concern is the possibility of parenchymal fibrosis and lung dysfunction in long-term COVID-19 patients. Furthermore, it has been observed that up to 43% of individuals hospitalized with COVID-19 also had acute renal injury (AKI). Care for kidney, brain, lung, cardiovascular, liver, ocular, and tissue injuries should be included in post-acute COVID-19 treatment. As a powerful immunomodulatory tool in regenerative medicine, dental stem cells (DSCs) have drawn much interest. Numerous immune cells and cytokines are involved in the excessive inflammatory response, which also has a significant effect on tissue regeneration. A unique reservoir of stem cells (SCs) for treating acute lung injury (ALI), liver damage, neurological diseases, cardiovascular issues, and renal damage may be found in tooth tissue, according to much research. Moreover, a growing corpus of in vivo research is connecting DSC-derived extracellular vesicles (DSC-EVs), which are essential paracrine effectors, to the beneficial effects of DSCs. DSC-EVs, which contain bioactive components and therapeutic potential in certain disorders, have been shown as potentially effective therapies for tissue damage after COVID-19. Consequently, we explore the properties of DSCs in this work. Next, we\'ll look at how SARS-CoV-2 affects tissue damage. Lastly, we have looked at the use of DSCs and DSC-EVs in managing COVID-19 and chronic tissue damage, such as injury to the heart, brain, lung, and other tissues.

Osteosarcoma (OS) is a rare malignant tumor that affects soft tissue and has high rates of lung metastasis and mortality. The primary treatments for OS include preoperative chemotherapy, surgical resection of the lesion, and postoperative chemotherapy. However, OS chemotherapy presents critical challenges related to treatment toxicity and multiple drug resistance. To address these challenges, nanotechnology has developed nanosystems that release drugs directly to OS cells, reducing the drug\'s toxicity. Extracellular vesicles (EVs) are nanosized lipid-bilayer bound vesicles that act as cell-derived vehicles and drug delivery systems for several cancers. This study aims to utilize EVs for OS management by co-delivering Hdac1 siRNA and zoledronic acid (zol). The EVs\' surface is modified with folic acid (FA) and their targeting ability is compared to that of native EVs. The results showed that the EVs\' targeting ability depends on the parent cell source, and FA conjugation further enhanced it. Furthermore, EVs were used as the carrier for co-loading drug (zol) and small RNA (Hdac-1). This approach of using surface engineered EVs as carriers for cargo loading and delivery can be a promising strategy for osteosarcoma management.

Mesenchymal stem-cell-derived extracellular vesicles (MSC-EVs) have been increasingly investigated for cancer therapy and drug delivery, and they offer an advanced cell-free therapeutic option. However, their overall effects and efficacy depend on various factors, including the MSC source and cargo content. In this study, we isolated EVs from the conditioned medium of human immature dental pulp stem cells (hIDPSC-EVs) and investigated their effects on two papillary thyroid cancer (PTC) cell lines (BCPAP and TPC1). We observed efficient uptake of hIDPSC-EVs by both PTC cell lines, with a notable impact on gene regulation, particularly in the Wnt signaling pathway in BCPAP cells. However, no significant effects on cell proliferation were observed. Conversely, hIDPSC-EVs significantly reduced the invasive capacity of both PTC cell lines after 120 h of treatment. These in vitro findings suggest the therapeutic potential of hIDPSC-EVs in cancer management and emphasize the need for further research to develop novel and effective treatment strategies. Furthermore, the successful internalization of hIDPSC-EVs by PTC cell lines underscores their potential use as nanocarriers for anti-cancer agents.

UNASSIGNED: The COVID-19 pandemic has caused significant morbidity and mortality globally. The role of plasma-derived extracellular vesicles (EVs) in pediatric COVID-19 patients remains unclear.
UNASSIGNED: We isolated EVs from healthy controls (n = 13) and pediatric COVID-19 patients (n = 104) with varying severity during acute and convalescent phases using serial ultracentrifugation. EV effects on healthy PBMCs, naïve CD4+ T cells, and monocytes were assessed through in vitro assays, flow cytometry, and ELISA.
UNASSIGNED: Our findings indicate that COVID-19 severity correlates with diverse immune responses. Severe acute cases exhibited increased cytokine levels, decreased IFNγ levels, and lower CD4+ T cell and monocyte counts, suggesting immunosuppression. EVs from severe acute patients stimulated healthy cells to express higher PDL1, increased Th2 and Treg cells, reduced IFNγ secretion, and altered Th1/Th17 ratios. Patient-derived EVs significantly reduced proinflammatory cytokine production by monocytes (p < .001 for mild, p = .0025 for severe cases) and decreased CD4+ T cell (p = .043) and monocyte (p = .033) populations in stimulated healthy PBMCs.
UNASSIGNED: This study reveals the complex relationship between immunological responses and EV-mediated effects, emphasizing the impact of COVID-19 severity. We highlight the potential role of plasma-derived EVs in early-stage immunosuppression in severe COVID-19 patients.