Aim: This study investigates the change in profiles of miRNAs in extracellular vesicles released during Toxoplasma gondii (T. gondii) infection. T. gondii has been implicated in host behavioural modifications and neuroinflammatory responses, yet the molecular mechanisms involved in these changes remain poorly understood. Extracellular vesicles, involved in intercellular communication, play an important role in host-pathogen interactions, particularly through the transfer of microRNAs (miRNAs); however, the impact of extracellular vesicle miRNAs in T. gondii infection remains largely unexplored.

Methods: Human BE(2)-M17 neuronal cells were infected with Toxoplasma gondii to investigate infection-induced changes in extracellular vesicle (EV) miRNA content. EVs from infected and control cultures were isolated, characterised, and subjected to miRNA extraction followed by next-generation sequencing and differential expression analysis using standard bioinformatic pipelines. Predicted miRNA targets were integrated across multiple databases and analysed for enriched pathways to identify neuronal regulatory networks.

Results: Pathway network analysis identified key neurobiological pathways, including neuroplasticity, neurotransmission, and neuroinflammation in high-confidence miRNA targets with gene enrichment of neurotrophin and long-term depression and long-term potentiation, which may underlie parasite-induced alterations in neural function. Bioinformatic analysis of extracellular vesicle miRNA profiles from infected and uninfected neuronal cells revealed a set of miRNAs including hsa-miR-4645-3p with significant upregulation in response to infection.

Conclusion: These findings suggest that T. gondii modulates host neuronal processes through extracellular vesicle-mediated miRNA transfer, providing a potential mechanistic link between infection and parasite-associated cognitive and neuropsychiatric disturbances.

A recent study on Cell Reports Medicine by Wang et al. introduces a hybrid exosome platform - selenized neural stem cell-derived exosomes (SeNExo) - that couples the biological functionality of neural stem cell exosomes with the antioxidant power of ultrasmall nanoselenium. SeNExo crosses the blood-brain barrier via apolipoprotein E (APOE)-lipoprotein receptor-associated protein-1 (LRP1) interaction, scavenges reactive oxygen species, and restores glial-neuron homeostasis. It demonstrates potent therapeutic efficacy in both traumatic brain injury and spinal cord injury mouse models. This work highlights a promising direction for engineering multifunctional, cell-free nanotherapeutics for central nervous system repair.

Mesenchymal stromal/stem cell-derived extracellular vesicles (MSC-EVs) have emerged as promising acellular therapeutics in regenerative medicine, offering a safer and more controllable alternative to whole-cell therapies. Their therapeutic efficacy, however, is highly dependent on their molecular cargo, which reflects the physiological state and environmental conditions of the parent MSCs. Priming of mesenchymal stromal/stem cells (MSCs) with defined stimuli such as hypoxia, inflammatory cytokines, 3D culture systems, biomaterials, or pharmacological agents has been increasingly employed to enhance extracellular vesicle (EV) bioactivity. These strategies modulate EV content, enriching vesicles with regenerative, immunomodulatory, angiogenic, and antioxidant factors. For instance, hypoxic priming activates hypoxia-inducible factor-1α-driven gene expression, promoting the packaging of angiogenic and anti-inflammatory molecules, while cytokine-based priming upregulates immunosuppressive proteins and regulatory microRNAs. Similarly, 3D culture mimics aspects of the native tissue microenvironment, augmenting the secretion of EVs with enhanced reparative potential. Emerging combination-based approaches synergize these effects, generating EVs with superior therapeutic profiles. Despite encouraging preclinical data, translation to clinical application is challenged by variability in MSC sources, priming conditions, and EV isolation methods. Standardization of protocols, validated potency assays, and regulatory harmonization are critical for clinical advancement. This mini-review summarizes current priming strategies, the underlying mechanisms influencing EV cargo, and their functional implications in disease models, while highlighting key barriers and future directions for the clinical translation of primed MSC-EV therapies.

Aim: To investigate the therapeutic potential and underlying mechanism of mesenchymal stem cell (MSC)-derived extracellular vesicles (MSC-EVs) in treating hepatorenal syndrome (HRS), a condition lacking therapies for multi-organ damage.

Methods: EVs were isolated from human umbilical cord MSCs and characterized by transmission electron microscopy, nanoparticle tracking analysis, and proteomics. A murine model of HRS, induced by bile duct ligation (BDL), was established, and mice received intravenous MSC-EVs treatment. Therapeutic efficacy was assessed through histopathology, serum biochemistry, and analysis of necroptosis, inflammation, and fibrosis markers.

Results: Proteomic profiling of MSC-EVs revealed significant enrichment of proteins involved in renal processes, anti-fibrosis, and immune regulation. In BDL-induced HRS mice, MSC-EVs treatment demonstrated potent multi-organ protective effects. This was evidenced by alleviation of hepatic necroptosis and renal tubular injury, downregulation of interleukin-17 expression, and concurrent attenuation of fibrosis in both liver and kidney tissues. Consequently, significant improvements in hepatic and renal function markers were observed.

Conclusion: MSC-EVs represent a novel and effective cell-free nanotherapeutic strategy for HRS. They confer protection through multi-faceted mechanisms, including inhibition of necroptosis, immune reprogramming, and fibrosis resolution, offering a promising paradigm for the treatment of multi-organ failure.

The existence of small vesicles released by cells into the extracellular space was first documented over 40 years ago. These nanoparticles, now recognized as extracellular vesicles (EVs), were originally defined as “cellular dust” reflecting the early belief that their primary function was to dispose of cellular waste. Nowadays, it is widely acknowledged that EVs make a fundamental contribution to intercellular communication, being capable of transporting biologically active molecules, including proteins and nucleic acids, which regulate both physiological and pathological processes. Their involvement in various diseases, particularly cancer, has been well documented. EVs influence tumor development, progression, and therapeutic response, and have therefore been considered potential diagnostic and prognostic biomarkers. In this review, we focus on the contribution of EVs in modulating tumor cell metabolism and the tumor microenvironment. Specifically, we describe how EVs promote angiogenesis, induce the transformation of fibroblasts into cancer-associated fibroblasts, and influence extracellular matrix remodeling. Additionally, we explore their contribution to the reprogramming of tumor metabolism, including glycolytic, lipid, and amino acid pathways. We provide an in-depth overview of the key molecules carried by EVs that contribute to these pro-tumorigenic effects and of the underlying mechanisms involved.

Aim: This proof-of-concept study aimed to evaluate the impact of fluorescence-based sorting on the microRNA (miRNA) molecular profile of extracellular vesicles (EVs) derived from adipose-derived mesenchymal stromal cells (ASCs) (ASC-EVs), with a focus on osteoarthritis (OA) as a model disease.

Methods: ASCs from five human donors were characterized by flow cytometry and cultured to collect conditioned media. EV isolation was performed by fluorescence-based sorting using a high-sensitivity cell sorter calibrated for particles ≥ 100 nm. In both ASC-EVs and sorted ASC-EVs (sASC-EVs), EV and MSC markers were analysed by flow cytometry, while size and morphology were assessed via nanoparticle tracking analysis and electron microscopy. Small RNA sequencing was used to profile miRNAs, followed by differential expression and functional enrichment analyses.

Results: EVs displayed comparable size distributions and surface marker profiles before and after sorting. In contrast, small RNA sequencing revealed a marked reduction in the number of detectable miRNAs in sASC-EVs relative to EVs isolated by standard ultracentrifugation (285 vs. 749). Among these, 271 miRNAs were shared between groups, exhibiting a strong correlation in relative abundance and functional enrichment in angiogenesis, inflammation modulation and gene silencing pathways. Nevertheless, differential expression analysis identified 32 upregulated and 6 downregulated miRNAs in sASC-EVs, with 14 miRNAs detected exclusively after sorting. Despite these transcriptional differences, the overall balance between protective and detrimental OA-related miRNAs remained positive and was preserved across both ASC-EVs and sASC-EVs.

Conclusion: While sorting reduces EV-associated miRNA diversity, it retains core functional signals. The difference in recovered miRNAs may be due to lower EV recovery, exclusion of miRNA-bound non-vesicular particles or loss of small EVs undetectable by fluorescence-based sorting techniques. Overall, these preliminary findings highlight a trade-off between purity and complexity, underscoring the importance of optimizing EV isolation protocols for clinical applications.

Ovarian cancer is one of the leading causes of gynecologic cancer-related mortality in women. However, a significant proportion of ovarian cancer cases are only detected at an advanced stage (III or IV) and are complicated to treat because of metastasis to the peritoneum. This challenge is compounded by vague symptoms and insufficient screening methods for early ovarian cancer detection. A promising solution is liquid biopsy, where the presence of biomarkers (proteins, lipids, and nucleic acids) associated with cancer is identified in the blood circulation. This approach facilitates the real-time monitoring of cancer progression and treatment effects in a non-invasive manner. This contrasts with traditional tumor biopsy, where only a small portion of the tumor is sampled, serial sampling of the tumor is impractical, or sometimes, tumor biopsy is not feasible. This review discusses the cell-free and extracellular vesicle components in blood, highlighting their DNA as a target in liquid biopsies for cancer diagnostics, with a specific emphasis on ovarian cancer. It also underscores the need for further research into the biological underpinnings and functional roles of these DNA fragments to integrate them into multi-omics approaches for detailed insights into tumor biology and treatment resistance in ovarian cancer.

Aim: The rising prevalence of opioid use during pregnancy poses serious public health concerns. The placenta is a critical organ during gestation, and opioid exposure can disrupt its function and fetal development. However, the molecular mechanisms through which opioids such as oxycodone affect feto-placental development remain poorly understood. This study aimed to investigate the effects of chronic in-utero oxycodone exposure on the composition and signaling functions of placenta-derived small extracellular vesicles (PSEVs) using a rat model.

Methods: Extracellular vesicles (EVs) were isolated from placental tissue and characterized through nanoparticle tracking analysis, transmission electron microscopy, western blotting, and label-free quantitative proteomics. Bioinformatic enrichment analyses were conducted to evaluate changes in EVs biophysical properties and protein cargo.

Results: Chronic oxycodone exposure significantly altered PSEV characteristics, including particle size distribution and proteomic composition. Among the 456 identified EV proteins, 107 proteins were significantly dysregulated. We found key downregulatory proteins including Atp2a2, Lmna, Tgfb3, Agt, and Sgce, which are crucial for myocardial calcium cycling, nuclear integrity, extracellular matrix remodeling, and blood pressure regulation. These findings indicate disruptions in fetal cardiac programming, particularly hypertrophic and dilated cardiomyopathy pathways. Additionally, enrichment analyses revealed notable perturbations in metabolic processes (e.g., citrate cycle, fatty acid degradation, N-glycan biosynthesis), along with upregulation of vesicle transport and neurodevelopment-related proteins, indicating broader systemic effects on fetal development. While these proteomic findings are robust, further independent validation (e.g., via targeted assays or Western blotting) will be necessary to confirm individual protein-level changes.

Conclusion: These results highlight PSEVs as sensitive molecular indicators linking maternal oxycodone use to disrupted fetal cardiovascular, metabolic, and neurodevelopmental pathways. This study provides a novel systems-level framework for understanding opioid-induced placental signaling alterations and lays the groundwork for developing EV-based diagnostic biomarkers and targeted interventions.

Extracellular vesicles (EVs) are heterogeneous, lipid bilayer-enclosed vesicles secreted by cells. Research on EVs dates back to the 1940s, and the term “exosomes” - a major subtype of EVs - was coined in 1981 to describe small membrane vesicles shed from cells. However, it is only in the past two decades that research in this area has expanded rapidly. By transferring functional biomolecules, EVs play a pivotal role in intercellular communication and regulate a wide range of cellular functions under both physiological and pathological conditions. Owing to their high biocompatibility, capacity to protect encapsulated cargo from degradation, and ability to cross biological barriers, EVs also show great promise as biomarkers and drug-delivery systems. Following the first, albeit unintentional, isolation of EVs in 1946, the 80th anniversary of EV research is now approaching. In this review, we trace the history of EV research and summarize key advances in the field. We also discuss current challenges and future prospects in this rapidly evolving area.

Aim: This study aimed to investigate whether vesicle-like nanoparticles derived from the GeGen decoction (GGD-PDVLNs) represent a key bioactive component responsible for its anti-colitis effects and to elucidate their underlying mechanisms, particularly focusing on gut microbiota modulation.

Methods: The GeGen decoction (GGD) was subjected to differential centrifugation following boiling, yielding vesicle-like nanoparticles. Structural analysis confirmed that these nanoparticles have a lipid bilayer and can resist digestion by simulated gastrointestinal fluids. These nanoparticles were administered orally to mice with chronic colitis induced by dextran sulfate sodium to evaluate their therapeutic effects.

Results: GGD-PDVLNs effectively mitigated intestinal inflammation by reducing the secretion of pro-inflammatory cytokines [interleukin (IL)-6, IL-1β, tumor necrosis factor-alpha (TNF-α)], elevating levels of the anti-inflammatory cytokine IL-10, alleviating intestinal damage, and enhancing intestinal barrier function, all while exhibiting a favorable biosafety profile. Notably, their therapeutic action depended on gut microbiota modulation. GGD-PDVLNs restored microbial homeostasis, increased microbial diversity, and enriched probiotic populations. In pseudo-germ-free mice, GGD-PDVLNs lost efficacy, confirming microbiota-dependent mechanisms.

Conclusion: Vesicle-like nanoparticles are an important active component of GGD. Our findings demonstrate that GGD-PDVLNs significantly ameliorate colonic inflammation through microbiota-dependent mechanisms.

Extracellular vesicles (EVs) are emerging as promising tools for regenerative medicine and drug delivery, offering unique therapeutic advantages. However, their clinical translation - in Australia and globally - faces persistent challenges. These are commonly framed as technical issues stemming from inherent EV variability and the absence of standardized potency assays. While no EV-based therapeutic has yet received full market approval from any major regulatory agency, this Perspective argues that the barriers to translation are not solely technical but reflect limitations within current regulatory frameworks. In Australia, the Therapeutic Goods Administration (TGA) requires biological products to be included on the Australian Register of Therapeutic Goods (ARTG) before supply to market. However, several alternative regulatory pathways exist that can facilitate clinical access to “unapproved” products. Through analysis of these pathways, and comparison with international approaches, this Perspective highlights how regulatory inflexibility may be as significant a barrier to translating EV medicines as the technical difficulties themselves. Drawing on insights from governmental inquiries into the approval and subsidization of emerging medicines, the Perspective calls for reform of Australia’s regulatory systems - including development of EV-specific guidance and policy that introduces adaptive assessment pathways - to better support the safe and timely integration of novel biotechnologies.