A Comparison of Cellular Uptake Mechanisms, Delivery Efficacy, and Intracellular Fate between Liposomes and Extracellular Vesicles

Exploring the effects of cannabidiol encapsulation in liposomes on their physicochemical properties and biocompatibility

Cannabidiol (CBD) is recognized for its therapeutic properties in various conditions. However, CBD's limited water solubility and sensitivity to environmental stresses hinder its efficacy and bioavailability. Encapsulation in drug delivery systems, particularly liposomes, offers a promising solution. This study aims to prepare CBD-containing liposomes using commercially used lipids distearoyl phosphatidylcholine (DSPC) and dipalmitoyl phosphatidylcholine (DPPC), and 1,2 distearoyl-sn-glycero-3 phosphoethanolamine-N-[carbonyl-amino(polyethylene glycol)-4300] (ammonium salt) (DSPE-PEG) and to perform in vitro studies - cell viability and CBD release. Liposomes were synthesized using thin-film hydration method, and characterized by Fourier-transform infrared (FT-IR) spectroscopy, dynamic light scattering (DLS), and scanning transmission electron microscopy (STEM). DLS analysis revealed that CBD incorporation reduced liposome size by 23-53%, depending on the liposomes. Encapsulation efficiency followed the order: DPPC CBD (63%) < DSPC CBD (74%) < DSPC DPPC CBD (81%) < DSPC DSPE-PEG CBD (87%). CBD release profiles indicated that DPPC CBD liposomes released the highest CBD amount initially, while DSPC DSPE-PEG CBD exhibited sustained release, achieving 79% release over 504 h. In vitro cell viability tests showed that blank liposomes were non-cytotoxic. However, CBD-loaded liposomes significantly reduced cell viability for defined type of CBD containing liposomes. The inclusion of DSPE-PEG improved encapsulation efficiency and liposome stability, making DSPC DSPE-PEG CBD liposomes more suitable for long-term CBD release. Compared to other studies, encapsulation of CBD in liposomes enhances its bioavailability, allowing lower concentrations of CBD to be directly delivered to cells, resulting in observable changes in cell viability.

Optimizing gene editing in pigs: The role of electroporation and lipofection

The production of genetically modified pigs is becoming increasingly important in both the agricultural and biomedical fields. Optimization of these processes is a key objective to improve the precision, scalability and viability of genetically modified animals for research and commercial applications. Among the available techniques, electroporation and lipofection have emerged as promising alternatives to traditional methods such as microinjection and somatic cell nuclear transfer (SCNT) due to their simplicity, cost-effectiveness, and potential for high-throughput applications. These methods allow the direct delivery of CRISPR/Cas components into zygotes and embryos, reducing the technical expertise required and bypassing some of the challenges associated with cloning. This review examines the application, efficacy, and outcomes of electroporation and lipofection as gene editing techniques in porcine gametes and embryos. We provide a comprehensive synthesis of recent advances, compare their efficacy, and discuss their potential in agricultural and biomedical research. The principles and mechanisms of both methods are reviewed, highlighting their advantages, such as cost-effectiveness and ease of implementation, over traditional approaches such as microinjection. In addition, we address their limitations, including variability in efficiency, and discuss recent protocol optimizations aimed at improving reproducibility and applicability. By analyzing these developments, this review provides valuable insights into the evolving role of electroporation and lipofection in porcine genetic modification strategies.

Liposomal formulation of a vitamin C derivative: a promising strategy to increase skin permeability

This study describes the development of a novel liposomal formulation incorporating 3-O-ethyl-L-ascorbic acid (EAA), a derivative of vitamin C. The EAA-loaded liposomes were fully characterized, particle size and zeta potential values suitable for drug delivery. The skin penetration studies revealed that liposomal formulation enhanced EAA retention in the skin compared to free EAA. Additionally, the impact of topical treatments with liposomal EAA on photo-aging markers in skin explants was investigated. EAA charged liposomes display a protective or stimulatory effect on cellular metabolism. Finally, liposomal EAA have a significant effect on the inflamatory markers, reducing the extracellular matrix degradation associated with UV-induced damage of skin. These findings provide valuable insights into the potential of liposomal formulations for the development of advanced cosmetic products.

Mitochondrial-targeted liposome-based drug delivery - therapeutic potential and challenges

Liposomes, as nanocarriers for therapeutics, are a prominent focus in translational medicine. Given their biocompatibility, liposomes are suitable drug delivery systems rendering highly efficient therapeutic outcomes with minimal off-site toxicity. In different scenarios of human disease, it is essential not only to maintain therapeutic drug levels but also to target them to the appropriate intracellular compartment. Mitochondria regulate cellular signalling, calcium balance, and energy production, playing a crucial role in various human diseases. The notion of focusing on mitochondria for targeted drug delivery was proposed several decades ago, yet the practical application of this idea and its translation to clinical use is still in development. Mitochondrial-targeted liposomes offer an alternative to standard drug delivery systems, potentially reducing off-target interactions, side effects, and drug dosage or frequency. To advance this field, it is imperative to integrate various disciplines such as efficient chemical design, pharmacology, pharmaceutics, and cell biology. This review summarises scientific advances in the design, development and characterisation of novel liposome-based drug delivery systems targeting the mitochondria while revisiting their translational potential.

Construction and validation of a cell based reporter assay for identifying inhibitors of SARS coronavirus 2 RNA dependent RNA polymerase activity

Targeting RNA-dependent RNA polymerase (RdRp), a highly conserved enzyme essential for SARS coronavirus 2 (SARS-CoV-2) replication and transcription, represents a promising antiviral strategy due to its lower mutation rate than structural proteins such as Spike. This study introduces a cell-based assay system for screening potential SARS-CoV-2 RdRp inhibitors, contributing to ongoing efforts to identify effective antiviral agents. The assay utilizes a reporter vector containing the 3' untranslated region (UTR), luciferase reporter gene, and 5' UTR gene, sequentially arranged in reverse under the control of the cytomegalovirus promoter in the pcDNA3.1 vector. Co-transfection with SARS-CoV-2 RdRp resulted an increase in luminescence-based quantification of RdRp activity, achieving a Z-factor of 0.605, indicative of high reproducibility and reliability for high-throughput screening. Established RdRp inhibitors, including remdesivir, molnupiravir, tenofovir, and sofosbuvir, significantly reduced reporter activity, with remdesivir exhibiting the strongest inhibition. A newly identified RdRp inhibitor was further validated through primer extension polymerase and NMPylation assays, along with virus-based experiments, confirming its inhibitory mechanism. These results highlight the utility of this screening system in identifying effective RdRp-targeting antivirals, reinforcing the strategic importance of RdRp inhibition in combating SARS-CoV-2 and emerging variants.

Enhancing Intracellular Uptake of Ivermectin through Liposomal Encapsulation

Ivermectin (IVM), an antiparasitic drug approved by the Food and Drug Administration (FDA), is widely used to treat several neglected tropical diseases, including onchocerciasis, helminthiases, and scabies. Additionally, IVM has shown potential as a potent inhibitor of certain RNA viruses, such as SARS-CoV-2. However, IVM is highly hydrophobic, essentially insoluble in water, which limits its bioavailability and therapeutic effectiveness. The use of liposomes as drug carriers offers several advantages, including enhanced solubility for lipophilic drugs, passive targeting of immune system cells, sustained release, and improved tissue penetration. To address the limitations of IVM, including its poor solubility and bioavailability, liposomal formulations were developed using a combination of soyphosphatidylcholine (SPC), dioleylphosphatidylcholine (DOPC), cholesterol (Ch), and diethylphosphate (DCP) in two distinct molar ratios (1.85:1:0.15 and 7:2:1) via the ethanol injection method. The physicochemical properties of the placebo and IVM-loaded liposomes were extensively characterized in our earlier study, including the particle size, polydispersity index, and zeta potential. The present work adds a deeper level of investigation into how to effect cellular uptake and cytotoxicity in vitro of both free IVM and IVM-loaded liposomes in Vero E6 cells. The half-maximal cytotoxic concentrations (CC50) for free IVM and IVM-loaded liposomes were 10 μM and > 110 μM, respectively and the cellular uptake of IVM-loaded liposomes ranged from 13 to 60%, whereas free IVM showed a significantly lower uptake of only 2%. These results demonstrate that liposomal encapsulation effectively enhances IVM's cellular uptake while reducing its cytotoxicity, thus offering a promising strategy for improving the effectiveness of IVM.

Cyclic RGD modified dextran-quercetin polymer micelles for targeted therapy of breast cancer

Quercetin is a natural flavonoid found in many plants which has various pharmacological activities including antitumor effect. However, the poor water solubility and bioavailability limit the potential benefits of quercetin for patients. Thus, modifying quercetin structure and developing actively targeted drug delivery systems are extremely important for tumor precision therapy. Herein, polymer-drug conjugates dextran-quercetin (D-Q) and cRGD-dextran (R-D) were synthesized by grafting quercetin and polypeptide cRGDfk (Arg-Gly-Asp-(D-Phe)-Lys) to dextran. Then cRGD-modified dextran-quercetin polymer micelles (R-D-Q) were constructed by self-assembling of D-Q and R-D. R-D-Q micelles possessed appropriate particle size (133.4 nm), nearly neutral potential (8.14 mV) and excellent drug-loading efficiency (13.1 %) and achieved higher cytotoxicity, apoptosis induction and penetration to human breast cancer MCF-7 cells than the micelles unmodified with cRGD, which were ascribed to cRGD-integrin mediated transcytosis. R-D-Q micelles effectively suppressed tumor growth in tumor-bearing mice by delivering more quercetin throughout the tumor tissue. And R-D-Q micelles could promote the apoptosis of tumor cells by activating p38 and JNK signal pathways and suppressing ERK signal pathway. In addition, R-D-Q micelles had no damage to normal tissues of mice at therapeutic dose. These results indicate promising prospects for R-D-Q micelles as an effective drug delivery system against tumor.

Direct Cytosolic Delivery of Nanovesicles via Gigahertz Acoustic Streaming

The development of advanced intracellular delivery systems is essential for biopharmaceutical progress, particularly in drug delivery systems, genetic engineering, and cellular therapeutics. While nanovesicles show significant therapeutic potential, challenges remain due to cell membrane barriers and the limitations of endocytosis-mediated pathways. In this study, we introduce an efficient acoustofluidic delivery system that utilizes a gigahertz (GHz)-range bulk acoustic wave (BAW) resonator to generate spatiotemporally controlled acoustic streaming vortices. This system enables rapid (within 10 min) and highly efficient direct cytosolic delivery of nanovesicles by bypassing conventional endosomal entrapment pathways. It effectively delivers both synthetic drug carriers (doxorubicin-loaded small unilamellar vesicles, Dox-SUVs) and biologically active exosomes through GHz-driven hydrodynamic shear forces that induce transient membrane permeability while maintaining cellular viability (>91.5% at 300 mW). Key performances demonstrate 86.5% drug delivery efficiency for Dox-SUVs with near-complete nuclear accumulation, while exosome-mediated delivery exhibits 2.4-fold accelerated migration and 3-fold proliferation enhancement within 24 h. The system's capacity to modulate fluidic shear stresses via BAW power tuning (100-500 mW) allows precise control over membrane permeabilization kinetics and cargo flux. By overcoming endolysosomal sequestration through a noninvasive, physics-driven mechanism, this acoustofluidic approach expands opportunities for next-generation therapeutics, including macromolecular biologic delivery, genome editing, and exosome-mediated intercellular communication.

Trojan Horse-Like Vehicles for CRISPR-Cas Delivery: Engineering Extracellular Vesicles and Virus-Like Particles for Precision Gene Editing in Cystic Fibrosis

The advent of genome editing has kindled the hope to cure previously uncurable, life-threatening genetic diseases. However, whether this promise can be ultimately fulfilled depends on how efficiently gene editing agents can be delivered to therapeutically relevant cells. Over time, viruses have evolved into sophisticated, versatile, and biocompatible nanomachines that can be engineered to shuttle payloads to specific cell types. Despite the advances in safety and selectivity, the long-term expression of gene editing agents sustained by viral vectors remains a cause for concern. Cell-derived vesicles (CDVs) are gaining traction as elegant alternatives. CDVs encompass extracellular vesicles (EVs), a diverse set of intrinsically biocompatible and low-immunogenic membranous nanoparticles, and virus-like particles (VLPs), bioparticles with virus-like scaffold and envelope structures, but devoid of genetic material. Both EVs and VLPs can efficiently deliver ribonucleoprotein cargo to the target cell cytoplasm, ensuring that the editing machinery is only transiently active in the cell and thereby increasing its safety. In this review, we explore the natural diversity of CDVs and their potential as delivery vectors for the clustered regularly interspaced short palindromic repeats (CRISPR) machinery. We illustrate different strategies for the optimization of CDV cargo loading and retargeting, highlighting the versatility and tunability of these vehicles. Nonetheless, the lack of robust and standardized protocols for CDV production, purification, and quality assessment still hinders their widespread adoption to further CRISPR-based therapies as advanced "living drugs." We believe that a collective, multifaceted effort is urgently needed to address these critical issues and unlock the full potential of genome-editing technologies to yield safe, easy-to-manufacture, and pharmacologically well-defined therapies. Finally, we discuss the current clinical landscape of lung-directed gene therapies for cystic fibrosis and explore how CDVs could drive significant breakthroughs in in vivo gene editing for this disease.

Streptococcus mutans-derived extracellular vesicles promote skin wound healing via tRNA cargo

BACKGROUND

The human oral cavity harbors a diverse microbiota, including Streptococcus species. Oral mucosal wounds heal rapidly, although the exact cause remains unclear. This study investigates the impact of Streptococcus mutans-derived extracellular vesicles (Sm EVs) on wound healing in both oral mucosal organoids and mouse skin. To explore whether microbial EV RNA cargo influences wound healing, RNA sequences from Sm EVs were identified, and the most abundant sequences were synthesized into oligomers and encapsulated in E. coli EVs (Ec EVs) for further in vivo testing. We assessed the role of Toll-like receptor 3 (TLR3) in the wound healing mechanism in TLR3 knockout (KO) mice.

RESULTS

Sm EVs significantly enhanced cell proliferation and migration in oral mucosa, with enhanced focal adhesion complex formation. Sm EVs improved wound healing in mouse dorsal skin compared to PBS controls. RNA sequencing revealed that bacterial tRNAs, particularly the tRNA-Met variant (Oligo 1), were the most abundant RNAs in Sm EVs. Ec EVs carrying Oligo 1 produced similar wound healing effects to Sm EVs in mucosal organoids and mouse dorsal skin. However, in TLR3 knockout mice, Oligo 1 did not improve wound healing.

CONCLUSIONS

This study highlights the role of Sm EVs, particularly their tRNA variants, in promoting skin wound healing through a TLR3-dependent mechanism. These findings suggest that EVs from oral commensal bacteria may offer therapeutic potential for chronic, non-healing skin wounds.

Microglia-targeting nanosystems that cooperatively deliver Chinese herbal ingredients alleviate behavioral and cognitive deficits in Alzheimer's disease model mice

The effective treatment of Alzheimer's disease (AD) is challenging because of its complex and controversial pathological mechanisms. Moreover, multiple barriers, such as the blood-brain barrier (BBB), reduce drug delivery efficiency. Microglia-related neuroinflammation has recently attracted increasing attention as a possible cause of AD and has become a novel therapeutic target. Therefore, overcoming the BBB and targeted delivery of anti-inflammatory agents to microglia seem to be effective practical strategies for treating AD. A large proportion of natural active extracts possess exceptional immunomodulating capabilities. In this study, the cooperative delivery of berberine (Ber) and palmatine (Pal) by transferrin-decorated extracellular vesicles (Tf-hEVs-Ber/Pal), which can cross the BBB and precisely target microglia, was performed. This nanosystem effectively cleared amyloid β-protein (Aβ) aggregates, significantly regulated the neuroinflammatory environment both in vitro and in vivo and markedly altered the behavior and improved the cognitive and learning abilities of AD model mice. The efficacy of a microglia-targeting combined therapeutic approach for AD was demonstrated, which broadens the potential application of Chinese herbal ingredients.

Enhanced Adhesion of Mildly Positively Charged Vesicles to Endothelial Cells with Shed Glycocalyx

The glycocalyx of endothelial cells is a dynamic, gel-like layer of glycoproteins, proteoglycans, and glycolipids that lines the luminal surface of blood vessels, playing a critical role in vascular permeability, mechanotransduction, and protection against shear stress. In this study, we investigated the in vitro adhesion of giant unilamellar vesicles (GUVs) composed of 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) and 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC). Specifically, we examined mildly positively charged DOTAP-DMPC (20:80) GUVs, based on positively charged DOTAP and neutral DMPC but exhibiting an overall mild positive charge in physiological buffer, and neutral DMPC GUVs, which show a negative charge in physiological buffer. Adhesion to human umbilical vein endothelial cells (HUVEC) was studied under three culture conditions: dynamic (intact glycocalyx), static (underdeveloped glycocalyx), and glycocalyx-shed (degraded glycocalyx). Vesicles were produced via electroformation, stained with Texas Red dye, and perfused over endothelial cells at a controlled velocity to simulate slow blood flow. Adhesion was tracked using fluorescence microscopy combined with cell segmentation techniques. Adhesion of DOTAP-DMPC vesicles was significantly enhanced-by approximately 3.5-fold-on glycocalyx-shed cells compared to cells with an intact glycocalyx. In contrast, DMPC vesicles showed no adhesion under any condition. Analysis of vesicle size distributions revealed no significant differences between adherent and nonadherent vesicles or between DOTAP-DMPC and DMPC vesicles. These findings provide insights into the role of the endothelial glycocalyx in regulating adhesion, with potential implications for tumor cell interactions with the endothelium and mechanisms underlying DOTAP-based transfection.

Exploring the In Vivo Fate of β-1, 3/1, 6-Glucan Using Quantitative Tandem Mass Spectrometry Based on a Structure-Specific Fragment

β-glucan, a promising drug candidate for immuno-antitumor therapy, holds tremendous potential for clinical applications. However, the absence of highly sensitive quantitative methods for polysaccharides, attributed to their complicated chemical structures and susceptibility to endogenous interference, has posed significant challenges for their clinical development. Here, we report a highly sensitive and reliable analytical strategy for quantifying β-1, 3/1, 6-glucan derived from Durvillaea antarctica (BG136) in various biological matrices. This approach integrates targeted depolymerization and derivatization, followed by oligosaccharide isomer fingerprinting using ultra-high-performance liquid chromatography-triple quadrupole tandem mass spectrometry (UHPLC-MS/MS). The absolute quantification of BG136 relied on the abundance of the structure-specific trisaccharide (Glc-β1, 6-Glc-β1, 3-Glc) generated. This methodology not only facilitates prototype-based BG136 administration but also exhibits remarkable sensitivity. Following method optimization and validation, we successfully explored the in vivo fate of BG136 across multiple models, including cellular uptake and release kinetics, as well as preclinical and clinical pharmacokinetics. These achievements provide insight into the "black box" of BG136 from administration to elimination in vivo. This work marks the first practical application of this strategy in complex biological matrices, offering methodological support for the successful execution of the BG136 Phase I clinical trial.

Multifunctional Janus Nanoparticles Capable of Anchoring to the Cell Membrane and Serving as "Cellular Backpacks" for Advanced Theranostics

A cell-based theranostic system can be fabricated by attaching nanomedicines to the surface of carrier cells, but it remains a challenge to achieve the attachment without involving endocytosis. Herein, we address this challenge by developing multifunctional Janus nanoparticles with orthogonal surface properties for the two opposite halves. When incubated with carrier cells, the hydrophobic half made of polystyrene readily inserts into the plasma membrane, whereas the hydrophilic SiO2 half grafted with poly(ethylene glycol) protrudes away from the cell surface. Additionally, the SiO2 half can be made with a cavity to hold theranostic agents and thus serves as a "backpack" for the carrier cell. By confining the theranostic agents in the SiO2 compartment and outside the carrier cell during the delivery process, their adverse impact on the cell is minimized. Upon release in an in vitro spheroid model, the agents quickly eradicate cancer cells. Moreover, the polystyrene half can be loaded with superparamagnetic nanoparticles to enhance magnetic resonance imaging contrast and enable magnetic manipulation, facilitating image-guided and target-directed treatments. By further optimizing the interactions between the multifunctional Janus nanoparticles and carrier cells, this system can be developed into a robust platform for cell-based theranostics.

Hurdles to healing: Overcoming cellular barriers for viral and nonviral gene therapy

Gene delivery offers great potential for treating various diseases, yet its success requires overcoming several biological barriers. These hurdles span from extracellular degradation, reaching the target cells, and inefficient cellular uptake to endosomal entrapment, cytoplasmic transport, nuclear entry, and transcription limitations. Viruses and non-viral vectors deal with these barriers via different mechanisms. Viral vectors, such as adenoviruses, adeno-associated viruses, and lentiviruses use natural mechanisms to efficiently deliver genetic material but face limitations including immunogenicity, cargo capacity, and production complexity. Nonviral vectors, including lipid nanoparticles, polymers, and protein-based systems, offer scalable and safer alternatives but often fall short in overcoming intracellular barriers and achieving high transfection efficiencies. Recent advancements in vector engineering have partially overcome several of these challenges. Ionizable lipids improve endosomal escape while minimizing toxicity. Biodegradable polymers balance efficacy with safety, and engineered protein systems, inspired by viral or bacterial entry mechanisms, integrate multifunctionality for enhanced delivery. Despite these advances, challenges, particularly in achieving robust in vivo translatability, scalability, and reduced immunogenicity, remain. This review synthesizes current knowledge of cellular barriers and the approaches to overcome them, providing a roadmap for designing more efficient gene delivery systems. By addressing these barriers, the field can advance toward safer, and more effective therapies.

In vivo MRI of breast cancer using carbonic anhydrase IX proteoglycan-like domain -targeting liposomes

Molecular imaging of breast cancer is increasingly recognized as a valuable tool for optimizing therapeutic interventions. Among potential targets for molecular imaging reporters, Carbonic Anhydrase IX (CAIX) stands out for its overexpression in tumors characterized by large hypoxic areas and aggressive phenotypes. CAIX, a transmembrane glycoprotein involved in pH regulation, displays a unique proteoglycan-like (PG) domain, not present in other isoforms, that could represent a specific target for imaging and therapy. While high sensitivity imaging techniques such as Positron Emission Tomography (PET) and optical imaging have been applied for CAIX targeting, no in vivo study utilizing Magnetic Resonance Imaging (MRI) to target CAIX has yet been reported. Herein, we address this gap by applying CAIX PG-targeting functionalized liposomes in the first in vivo MRI study on a murine model of breast cancer. TS/A cells were subcutaneously injected to generate primary tumors in mice, and targeted liposomes were delivered intravenously after 15 days. Internalization of the targeted liposomes by receptor-mediated endocytosis led to an enhanced MRI signal in the tumor region. Cytoplasmic and endosomal distribution of the liposomes' payload was observed. Conversely, non-functionalized liposomes and liposomes bearing a scrambled peptide, while entering tumor cells in smaller amounts, localized only to endosomes as expected. The findings reported herein suggest that CAIX PG domain-targeting liposomal formulations exploiting receptor-mediated endocytosis can lead to improved diagnostic capabilities and open avenues for targeted therapeutic delivery for the treatment of tumors overexpressing CAIX, particularly breast cancer.

Syncytial therapeutics: Receptor-specific and direct-to-cytosol biologic drug delivery mediated by measles fusion complex

This work explores cell-cell fusion mediated by measles virus (MeV) as a potential new cell therapy modality that achieves direct-to-cytosol (DTC) drug delivery. MeV induces receptor-mediated fusion at the cell surface via its hemagglutinin (H) and fusion glycoproteins (F), bypassing endocytic membrane transport, and enabling direct cytosolic mixing between a fusogenic donor and host target cell. Fusion of this type gives rise to large syncytia formed by the inclusion of additional target cells over time. Fusion receptor specificity was first examined in CHO "non-target" and CHO "target" cells exogenously expressing the measles target SLAM (CHO-SLAM) by mono- or co-transfection of each cell type with plasmids encoding MeV-H and MeV-F. Fusion was observed only in CHO-SLAM cells which were co-transfected with both plasmids, which verified receptor-specificity without false-triggering of fusion in co-transfected "non-target" CHO or in MeV-F mono-transfectants of either cell type. Next, CHO donor cells with constitutive mCherry expression were co-transfected with MeV-H and MeV-F, and mCherry-positive syncytia were observed when cells were mixed with CHO-SLAM demonstrating the ability to deliver the mCherry payload via DTC. Increasing the cell dose does not affect the size distribution of resulting syncytia but contributes to a higher total mCherry delivery. Further, control of MeV stoichiometry can modulate the degree of syncytia formation and protein delivery, demonstrating that limiting MeV-H and increasing MeV-F favors fusion and cytosolic delivery. Taken together, these results demonstrate MeV cell-fusion-based, DTC delivery as a robust and tunable system for achieving targeted cytosolic delivery and controlled syncytia formation.

Mitochondria transfer for myelin repair

Demyelination is a common feature of neuroinflammatory and degenerative diseases of the central nervous system (CNS), such as multiple sclerosis (MS). It is often linked to disruptions in intercellular communication, bioenergetics and metabolic balance accompanied by mitochondrial dysfunction in cells such as oligodendrocytes, neurons, astrocytes, and microglia. Although current MS treatments focus on immunomodulation, they fail to stop or reverse demyelination's progression. Recent advancements highlight intercellular mitochondrial exchange as a promising therapeutic target, with potential to restore metabolic homeostasis, enhance immunomodulation, and promote myelin repair. With this review we will provide insights into the CNS intercellular metabolic decoupling, focusing on the role of mitochondrial dysfunction in neuroinflammatory demyelinating conditions. We will then discuss emerging cell-free biotherapies exploring the therapeutic potential of transferring mitochondria via biogenic carriers like extracellular vesicles (EVs) or synthetic liposomes, aimed at enhancing mitochondrial function and metabolic support for CNS and myelin repair. Lastly, we address the key challenges for the clinical application of these strategies and discuss future directions to optimize mitochondrial biotherapies. The advancements in this field hold promise for restoring metabolic homeostasis, and enhancing myelin repair, potentially transforming the therapeutic landscape for neuroinflammatory and demyelinating diseases.

Investigating the delivery of PD-L1-targeted immunoliposomes in a dynamic cervical cancer-on-a-chip model

The recent approval of pembrolizumab in recurrent or metastatic cervical cancer warrants further investigations into the usefulness of immunotherapies for more durable and less radical interventions. In this study, the targeting potential of anti-PD-L1-functionalized immunoliposomes was tested in a 3D in vitro cervical cancer-on-a-chip model. Immunolipsomes were synthesized and decorated externally with monovalent anti-PD-L1 Fab' fragments of commercially available atezolizumab. Cervical cancer cell lines with varying levels of PD-L1 expression were cultured as spheroids embedded in a collagen I matrix, and treated under flow of culture media. Flow cytometry and live-cell confocal imaging were used to measure the interactions and uptake of untargeted liposomes and immunoliposomes in this panel of cell lines. The immunoliposomes retained specific functionality regardless of protein corona formation in high serum environments. As such, spheroids expressing high levels of PD-L1 preferentially internalized immunoliposomes in a 3D environment with extracellular matrix present, while low PD-L1-expressing cell lines showed no preference for either formulation. Importantly, treatments performed in monolayer cultures (on plastic) showed no differences between immuno- and untargeted liposome uptake, including the way in which the endocytosed liposomes are trafficked subcellularly. This study demonstrates the importance of both active and passive accumulation strategies to achieve nanoparticle targeting. Immunoliposomes remain a promising platform for the development of targeted nanotherapies against cervical cancers. However, initial functional tests did not translate directly to biological performance and this should be kept in mind for future formulations. Furthermore, the in vitro model developed appeared useful for visualizing liposome uptake in a 3D, live tissue environment and represents a cost-effective and reproducible model for future studies.

Targeted delivery of cytotoxic proteins via lipid-based nanoparticles to primary Langerhans cells

Targeted delivery has emerged as a critical strategy in the development of novel therapeutics. The advancement of nanomedicine hinges on the safe and precise cell-specific delivery of protein-based therapeutics to the immune system. However, major challenges remain, such as developing an efficient delivery system, ensuring specificity, minimizing off-target effects, and attaining effective intracellular localization. Our strategy utilizes lipid-based nanoparticles conjugated with a glycomimetic ligand. These nanoparticles selectively bind to langerin, a C-type lectin receptor expressed on Langerhans cells in the skin. We opted for cytotoxic proteins, namely cytochrome c and saporin, as model proteins to showcase the potential of delivering intact proteins to Langerhans cells. These proteins are recognized for their ability to induce apoptosis upon entry into the cytosol. We observed specific killing of cells expressing langerin in vitro, and in primary Langerhans cells isolated from mouse and human skin ex vivo with minimal off target effects. By delivering functional proteins within lipid nanoparticles to Langerhans cells, our approach offers new potential to deliver effective therapeutics with minimal side effects.

Emerging Strategies for Revascularization: Use of Cell-Derived Extracellular Vesicles and Artificial Nanovesicles in Critical Limb Ischemia

Critical limb ischemia (CLI) poses a substantial and intricate challenge in vascular medicine, necessitating the development of innovative therapeutic strategies to address its multifaceted pathophysiology. Conventional revascularization approaches often fail to adequately address the complexity of CLI, necessitating the identification of alternative methodologies. This review explores uncharted territory beyond traditional therapies, focusing on the potential of two distinct yet interrelated entities: cell-derived extracellular vesicles (EVs) and artificial nanovesicles. Cell-derived EVs are small membranous structures naturally released by cells, and artificial nanovesicles are artificially engineered nanosized vesicles. Both these vesicles represent promising avenues for therapeutic intervention. They act as carriers of bioactive cargo, including proteins, nucleic acids, and lipids, that can modulate intricate cellular responses associated with ischemic tissue repair and angiogenesis. This review also assesses the evolving landscape of CLI revascularization through the unique perspective of cell-derived EVs and artificial nanovesicles. The review spans the spectrum from early preclinical investigations to the latest translational advancements, providing a comprehensive overview of the current state of research in this emerging field. These groundbreaking vesicle therapies hold immense potential for revolutionizing CLI treatment paradigms.

Mechanistic insight into human milk extracellular vesicle-intestinal barrier interactions

Human milk extracellular vesicles (EVs) are crucial mother-to-baby messengers that transfer biological signals. These EVs are reported to survive digestion and transport across the intestine. The mechanisms of interaction between human milk EVs and the intestinal mucosa, including epithelial uptake remain unclear. Here, we studied the interaction of human milk EVs with the gut barrier components, including intestinal biofluids, enzymes, mucus and epithelium. Additionally, we probed the endocytic mechanisms mediating the EV intestinal uptake. Finally, using proteomic analysis, we determined the existence and identification of proteins enriched in the EV fraction transported across the intestinal epithelium. We show that human milk EVs are largely stable in the biochemical gut barriers and demonstrate high mucus diffusivity. EVs show a high level of epithelial cell uptake (∼70%) and efficient transport across Caco-2 monolayers. Whilst cell uptake of EVs was mediated by multiple routes, none of the pathway-specific inhibitors inhibited their epithelial translocation. Proteomic analysis of EVs transported across Caco-2 monolayers identified 14 enriched EV proteins that may facilitate intestinal transport. These findings significantly expand our understanding of the interactions between human milk EVs and the gut barriers, including their intestinal uptake.

Mitigating inflammation and fibrosis: the therapeutic potential of quercetin liposomes in COPD

Introduction

Chronic obstructive pulmonary disease (COPD) is a disease with severe therapeutic obstacles and high worldwide death rate. COPD progresses predominantly through inflammatory response followed by fibrotic destruction. Quercetin (Que), recognized for its anti-inflammatory effects, presents significant promise as a therapeutic candidate for COPD therapy. However, poor water solubility and low bioavailability of Que hinder its further clinical application. Liposomes are renowned for their unique structure and function, which provided an efficient approach for the delivery of Que in various drug delivery systems. This study was aim to prepare a novel Que liposome (Que-lipo) and administrated via intratracheal (i.t.) with cigarette smoke induced COPD mice. The underlying therapeutic mechanisms against lung damage of Que-lipo were explored.

Methods

Que-lipo were prepared based on thin film dispersion method and administrated via intratracheal administration. The cigarette smoke induced COPD mice were established and a comprehensive approach was employed to explore the inflammation, pulmonary function and histopathology of lung after i.t. administration of Que-lipo, including enzyme-linked immunosorbent assay, histopathology and immunohistochemistry, reverse transcription-quantitative polymerase chain reaction.

Results and discussion

Que-lipo not only improved the solubility and biocompatibility of Que but also demonstrated effective cellular uptake in vitro. The inflammation, pulmonary function and pathological condition of lung were improved after i.t. administration of Que-lipo. Que-lipo also regulated the expression of key apoptosis-associated proteins such as Bcl-2 and caspase-3/7, leading to significant inhibition of apoptotic activity in COPD. Furthermore, Que-lipo markedly enhanced its ability to alleviate lung inflammation and fibrosis symptoms by modulating inflammation-related factors and fibrosis signaling molecules. The potential mechanisms of Que-lipo in treating COPD were elucidated, including the suppression of the NLRP3/IL-1β inflammasome pathway and the TGF-β1-related fibrosis signaling pathway.

Development of the Curcumin Analog CA7 Liposome and Its Evaluation for Efficacy Against Cervical Cancer in vitro and in vivo

Objective

The objective of this study was to develop liposomes (LP) containing a curcumin (CU) analog CA7 to enhance its pharmacokinetic profile and anti-cervical cancer (CC) effects.

Methods

Single-factor and Box-Behnken experiments were conducted to optimize the formulation of CA7-loaded liposomes (CA7-LP). The in vitro release, stability, biocompatibility, and pharmacokinetic of CA7-LP were evaluated. The biological effects of CA7-LP on Hela cells were assessed using MTT assays, colony formation assays, wound healing assays, and flow cytometry. Additionally, the anti-CC efficacy of CA7-LP was tested in mouse models of transplanted tumors.

Results

The optimal formulation of CA7-LP exhibited a particle size of 92.43 ± 1.52 nm, a polydispersity index of 0.27 ± 0.01, an encapsulation efficiency of 97.79 ± 1.49%, a drug loading of 3.23 ± 0.20%, and a zeta potential of -6.69 ± 0.77 mV. Transmission electron microscopy confirmed that a spherical morphology was exhibited by CA7-LP. The cumulative in vitro release of CA7-LP was found to be 2.84 times greater than that of CA7, and stability at room temperature was maintained for at least 90 d. Furthermore, a significantly higher uptake of CA7-LP by Hela cells was observed compared to curcumin and CA7, leading to enhanced inhibition of cell proliferation, migration and cell cycle, as well as increased apoptosis (p < 0.05). In vivo studies revealed that CA7-LP exhibited superior pharmacokinetic properties compared to CA7 (AUC: 3.58-fold, Cmax: 5.65-fold, t1/2z: 1.2-fold). The anti-CC effects of CA7-LP were found to be comparable to those of Cisplatin injection, with a better safety profile.

Conclusion

The newly developed CA7-LP is considered a promising candidate for the treatment of CC, demonstrating high potential for clinical application.

Optimization of lipofection protocols for CRISPR/Cas9 delivery in porcine zona pellucida intact oocytes: A study of coincubation duration and reagent efficacy

A priority to facilitate the application of lipofection to generate genetically modified porcine embryos and animals will be the use of zona pellucida (ZP)-intact oocytes and zygotes. Recently, our group produced genetically modified embryos by lipofection of ZP-intact oocytes during in vitro fertilization (IVF). This study investigates the effect of two commercial lipofection reagents, Lipofectamine 3000 and Lipofectamine CRISPRMAX, on embryo development and mutation efficiency in ZP-intact porcine oocytes. We compared these reagents with the electroporation method and a control group using two sgRNAs targeting the CAPN3 and CD163 genes. The detrimental effects on cleavage rates were observed in both lipofection treatments compared to the control and electroporated groups. However, blastocyst rates were higher in the Lipofectamine 3000 group than in the electroporated group for both genes. Mutation parameters varied by target gene, with Lipofectamine 3000 achieving higher mutation rates for CD163, while all groups were similar for the CAPN3 gene. Overall efficiency was similar for both lipofectamines, confirming their feasibility for use. In addition, we evaluated the effect of coincubation time (4, 8, and 24 h) on IVF outcomes, embryo development, and mutation parameters. Results indicated that an 8-h coincubation period optimized fertilization and mutation efficiency without significant toxic effects. This study demonstrates that lipofection with either Lipofectamine 3000 or CRISPRMAX during IVF is an effective method for generating genetically modified porcine embryos without the need for specialized equipment or trained personnel, with efficiencies similar to or greater than electroporation. This study also highlights the importance of optimizing reagent selection and coincubation times. There is no difference between Lipofectamine 3000 and CRISPRMAXTM in terms of embryo development and mutation efficiency, and under our experimental conditions, the optimal coincubation time with lipofectamine is 8 h.

Nanocarriers for intracellular delivery of proteins in biomedical applications: strategies and recent advances

Protein drugs are of great importance in maintaining the normal functioning of living organisms. Indeed, they have been instrumental in combating tumors and genetic diseases for decades. Among these pharmaceutical agents, those that target intracellular components necessitate the use of therapeutic proteins to exert their effects within the targeted cells. However, the use of protein drugs is limited by their short half-life and potential adverse effects in the physiological environment. The advent of nanoparticles offers a promising avenue for prolonging the half-life of protein drugs. This is achieved by encapsulating proteins, thereby safeguarding their biological activity and ensuring precise delivery into cells. This nanomaterial-based intracellular protein drug delivery system mitigates the rapid hydrolysis and unwarranted diffusion of proteins, thereby minimizing potential side effects and circumventing the limitations inherent in traditional techniques like electroporation. This review examines established protein drug delivery systems, including those based on polymers, liposomes, and protein nanoparticles. We delve into the operational principles and transport mechanisms of nanocarriers, discussing the various considerations essential for designing cutting-edge delivery platforms. Additionally, we investigate innovative designs and applications of traditional cytosolic protein delivery systems in medical research and clinical practice, particularly in areas like tumor treatment, gene editing and fluorescence imaging. This review sheds light on the current restrictions of protein delivery systems and anticipates future research avenues, aiming to foster the continued advancement in this field.

Modified PEG-Lipids Enhance the Nasal Mucosal Immune Capacity of Lipid Nanoparticle mRNA Vaccines

BACKGROUND/OBJECTIVES

Omicron, the predominant variant of SARS-CoV-2, exhibits strong immune-evasive properties, leading to the reduced efficacy of existing vaccines. Consequently, the development of versatile vaccines is imperative. Intranasal mRNA vaccines offer convenient administration and have the potential to enhance mucosal immunity. However, delivering vaccines via the nasal mucosa requires overcoming complex physiological barriers. The aim of this study is to modify PEGylated lipids to enhance the mucosal immune efficacy of the vaccine.

METHODS

The PEGylated lipid component of lipid nanoparticle (LNP) delivery vectors was modified with chitosan or mannose to generate novel LNPs that enhance vaccine adhesion or targeting on mucosal surfaces. The impact of the mRNA encoding the receptor-binding domain of Omicron BA.4/BA.5 on the immune response was examined.

RESULTS

Compared to the unmodified LNP group, the IgG and IgA titers in the chitosan or mannose-modified LNP groups showed an increasing trend. The chitosan-modified group showed better effects. Notably, the PEGylated lipid with 1.5 mol% of chitosan modification produced high levels of IgG1 and IgG2a antibodies, promoting Th1/Th2 responses while also generating high levels of IgA, which can induce stronger cellular immunity, humoral immunity, and mucosal immunity.

CONCLUSIONS

The 1.5 mol% of chitosan-modified LNPs (mRNA-LNP-1.5CS) can serve as a safe and effective carrier for intranasal mRNA vaccines, offering a promising strategy for combating the Omicron variant.

Nanoparticle-Based Drug Delivery Systems Enhance Treatment of Cognitive Defects

Nanoparticle-based drug delivery presents a promising solution in enhancing therapies for neurological diseases, particularly cognitive impairment. These nanoparticles address challenges related to the physicochemical profiles of drugs that hinder their delivery to the central nervous system (CNS). Benefits include improved solubility due to particle size reduction, enhanced drug penetration across the blood-brain barrier (BBB), and sustained release mechanisms suitable for long-term therapy. Successful application of nanoparticle delivery systems requires careful consideration of their characteristics tailored for CNS delivery, encompassing particle size and distribution, surface charge and morphology, loading capacity, and drug release kinetics. Literature review reveals three main types of nanoparticles developed for cognitive function enhancement: polymeric nanoparticles, lipid-based nanoparticles, and metallic or inorganic nanoparticles. Each type and its production methods possess distinct advantages and limitations. Further modifications such as coating agents or ligand conjugation have been explored to enhance their brain cell uptake. Evidence supporting their development shows improved efficacy outcomes, evidenced by enhanced cognitive function assessments, modulation of pro-oxidant markers, and anti-inflammatory activities. Despite these advancements, clinical trials validating the efficacy of nanoparticle systems in treating cognitive defects are lacking. Therefore, these findings underscore the need for researchers to expedite clinical testing to provide robust evidence of the potential of nanoparticle-based drug delivery systems.

Study of the uptake mechanism of two small extracellular vesicle subtypes by granulosa cells

As a new mechanism of intercellular communication, the uptake of extracellular vesicles (EVs) by receptor cells has become a hot topic in the field. Previously, research on the uptake of EVs has focused on the mechanism of small EVs (sEVs, also known as exosomes). As sEVs represent a mixed heterogeneous population, the issue of whether there are different uptake mechanisms for different subsets of sEVs by recipient cells urgently need to be addressed. There are EVs in follicular fluid, which play an important role in the communication between follicular cells and the development of oocytes. Previously, we isolated two subtypes of sEVs in follicular fluid: low density-sEVs (LD-sEVs) and high density-sEVs (HD-sEVs). The current study aimed to explore the uptake characteristics of these two subtypes of sEVs by granulosa cells. First, PKH67 was used to label the two sEVs subtypes, and we observed their uptake by granulosa cells using confocal microscopy and flow cytometry. We then explored the specific mechanisms underlying uptake of these two sEV subtypes by granulosa cells using specific inhibitors and RNA interference. The results showed that granulosa cells took up both kinds of sEVs through a clathrin-independent pathway. In addition to requiring caveolin, cholesterol, and Na+/H+ exchange, the uptake of HD-sEVs also depended on the activity of tyrosine kinase and phosphoinositide 3-kinase. A better understanding of the mechanism of granulosa cell uptake of different subtypes of sEVs in follicular fluid is of considerable significance leading to more accurate use of EVs for targeted treatment of infertility and other related diseases.

Insights into the unique roles of extracellular vesicles for gut health modulation: Mechanisms, challenges, and perspectives

Extracellular vesicles (EVs), which play significant regulatory roles in maintaining homeostasis and influencing immune responses, significantly impact gut microbiota composition and function, affecting overall gut health. Despite considerable progress, there are still knowledge gaps regarding the mechanisms by which EVs, including plant-derived EVs (PDEVs), animal-derived EVs (ADEVs), and microbiota-derived EVs (MDEVs), modulate gut health. This review delves into the roles and mechanisms of EVs from diverse sources in regulating gut health, focusing on their contributions to maintaining epithelial barrier integrity, facilitating tissue healing, eliciting immune responses, controlling pathogens, and shaping microbiota. We emphasize open challenges and future perspectives for harnessing EVs in the modulation of gut health to gain a deeper understanding of their roles and impact. Importantly, a comprehensive research framework is presented to steer future investigations into the roles and implications of EVs on gut health, facilitating a more profound comprehension of this emerging field.

Nanocarriers for targeted drug delivery in the vascular system: focus on endothelium

Endothelial cells (ECs) are pivotal in maintaining vascular health, regulating hemodynamics, and modulating inflammatory responses. Nanocarriers hold transformative potential for precise drug delivery within the vascular system, particularly targeting ECs for therapeutic purposes. However, the complex interactions between vascular ECs and nanocarriers present significant challenges for the development and clinical translation of nanotherapeutics. This review assesses recent advancements and key strategies in employing nanocarriers for drug delivery to vascular ECs. It suggested that through precise physicochemical design and surface modifications, nanocarriers can enhance targeting specificity and improve drug internalization efficiency in ECs. Additionally, we elaborated on the applications of nanocarriers specifically designed for targeting ECs in the treatment of cardiovascular diseases, cancer metastasis, and inflammatory disorders. Despite these advancements, safety concerns, the complexity of in vivo processes, and the challenge of achieving subcellular drug delivery remain significant obstacles to the effective targeting of ECs with nanocarriers. A comprehensive understanding of endothelial cell biology and its interaction with nanocarriers is crucial for realizing the full potential of targeted drug delivery systems.

Microfluidic technologies for lipid vesicle generation

Encapsulating biological and non-biological materials in lipid vesicles presents significant potential in both industrial and academic settings. When smaller than 100 nm, lipid vesicles and lipid nanoparticles are ideal vehicles for drug delivery, facilitating the delivery of payloads, improving pharmacokinetics, and reducing the off-target effects of therapeutics. When larger than 1 μm, vesicles are useful as model membranes for biophysical studies, as synthetic cell chassis, as bio-inspired supramolecular devices, and as the basis of protocells to explore the origin of life. As applications of lipid vesicles gain prominence in the fields of nanomedicine, biotechnology, and synthetic biology, there is a demand for advanced technologies for their controlled construction, with microfluidic methods at the forefront of these developments. Compared to conventional bulk methods, emerging microfluidic methods offer advantages such as precise size control, increased production throughput, high encapsulation efficiency, user-defined membrane properties (i.e., lipid composition, vesicular architecture, compartmentalisation, membrane asymmetry, etc.), and potential integration with lab-on-chip manipulation and analysis modules. We provide a review of microfluidic lipid vesicle generation technologies, focusing on recent advances and state-of-the-art techniques. Principal technologies are described, and key research milestones are highlighted. The advantages and limitations of each approach are evaluated, and challenges and opportunities for microfluidic engineering of lipid vesicles to underpin a new generation of therapeutics, vaccines, sensors, and bio-inspired technologies are presented.

MeCP2 is a naturally supercharged protein with cell membrane transduction capabilities

The intrinsically disordered protein MeCP2 is a global transcriptional regulator encoded by the MECP2 gene. Although the structured domains of MeCP2 have been the subject of multiple studies, its unstructured regions have not been that extensively characterized. In this work, we show that MeCP2 possesses properties akin to those of supercharged proteins. By utilizing its unstructured portions, MeCP2 can successfully transduce across cell membranes and localize to heterochromatic foci in the nuclei, displaying uptake levels a third lower than a MeCP2 construct fused to the cell-penetrating peptide TAT. MeCP2 uptake can further be enhanced by the addition of compounds that promote endosomal escape following cellular trafficking by means of macropinocytosis. Using a combination of in silico prediction algorithms and live-cell imaging experiments, we mapped the sequence in MeCP2 responsible for its cellular incorporation, which bears a striking resemblance to TAT itself. Transduced MeCP2 was shown to interact with HDAC3. These findings provide valuable insight into the properties of MeCP2 and may be beneficial for devising future protein-based treatment strategies.

Cationic liposomes overcome neutralizing antibodies and enhance reovirus efficacy in ovarian cancer

Reovirus (Reo) has shown promising potential in specifically killing tumor cells, and offering new possibilities for ovarian cancer (OC) treatment. However, neutralizing antibodies in the ascites from OC patients greatly limit the further application of Reo. In this study, we employed cationic liposomes (Lipo) to deliver Reo, significantly enhancing its ability to enter OC cells and its effectiveness in killing these cells under ascitic conditions. Pre-treatment with the MβCD inhibitor notably decreased Reo-mediated tumor cell death, indicating that Lipo primarily enables Reo's cellular uptake through caveolin-mediated endocytosis. Our results demonstrate that Lipo effectively facilitates the entry of Reo into the cytoplasm and triggers cell apoptosis. The above findings provide a new strategy to overcome the obstacle of neutralizing antibodies in the clinical application of Reo.

Engineered Microrobots for Targeted Delivery of Bacterial Outer Membrane Vesicles (OMV) in Thrombus Therapy

In the realm of thrombosis treatment, bioengineered outer membrane vesicles (OMVs) offer a novel and promising approach, as they have rich content of bacterial-derived components. This study centers on OMVs derived from Escherichia coli BL21 cells, innovatively engineered to encapsulate the staphylokinase-hirudin fusion protein (SFH). SFH synergizes the properties of staphylokinase (SAK) and hirudin (HV) to enhance thrombolytic efficiency while reducing the risks associated with re-embolization and bleeding. Building on this foundation, this study introduces two cutting-edge microrobotic platforms: SFH-OMV@H for venous thromboembolism (VTE) treatment, and SFH-OMV@MΦ, designed specifically for cerebral venous sinus thrombosis (CVST) therapy. These platforms have demonstrated significant efficacy in dissolving thrombi, with SFH-OMV@H showcasing precise vascular navigation and SFH-OMV@MΦ effectively targeting cerebral thrombi. The study shows that the integration of these bioengineered OMVs and microrobotic systems marks a significant advancement in thrombosis treatment, underlining their potential to revolutionize personalized medical approaches to complex health conditions.

Chitosan/PLGA-based tissue engineered nerve grafts with SKP-SC-EVs enhance sciatic nerve regeneration in dogs through miR-30b-5p-mediated regulation of axon growth

Extracellular vesicles from skin-derived precursor Schwann cells (SKP-SC-EVs) promote neurite outgrowth in culture and enhance peripheral nerve regeneration in rats. This study aimed at expanding the application of SKP-SC-EVs in nerve grafting by creating a chitosan/PLGA-based, SKP-SC-EVs-containing tissue engineered nerve graft (TENG) to bridge a 40-mm long sciatic nerve defect in dogs. SKP-SC-EVs contained in TENGs significantly accelerated the recovery of hind limb motor and electrophysiological functions, supported the outgrowth and myelination of regenerated axons, and alleviated the denervation-induced atrophy of target muscles in dogs. To clarify the underlying molecular mechanism, we observed that SKP-SC-EVs were rich in a variety of miRNAs linked to the axon growth of neurons, and miR-30b-5p was the most important among others. We further noted that miR-30b-5p contained within SKP-SC-EVs exerted nerve regeneration-promoting effects by targeting the Sin3a/HDAC complex and activating the phosphorylation of ERK, STAT3 or CREB. Our findings suggested that SKP-SC-EVs-incorporating TENGs represent a novel type of bioactive material with potential application for peripheral nerve repair in the clinic.

Facile fabrications of poly (acrylic acid)-mesoporous zinc phosphate/polydopamine Janus nanoparticles as a biosafe photothermal therapy agent and a pH/NIR-responsive drug carrier

Balancing biocompatibility and drug-loading efficiency in nanoparticles presents a significant challenge. In this study, we describe the facile fabrication of poly (acrylic acid)-mesoporous zinc phosphate/polydopamine (PAA-mZnP/PDA) Janus nanoparticles (JNPs). The PDA half-shell itself can serve as a photothermal agent for photothermal therapy (PTT), as well as to offers sites for polyethylene glycol (PEG) to enhance biocompatibility. Concurrently, the mesoporous ZnP core allows high loading of doxorubicin (DOX) for chemotherapy and the Cy5.5 dye for fluorescence imaging. The resultant PAA-mZnP/PDA-PEG JNPs exhibit exceptional biocompatibility, efficient drug loading (0.5 mg DOX/1 mg JNPs), and dual pH/NIR-responsive drug release properties. We demonstrate the JNPs' satisfactory anti-cancer efficacy, highlighting the synergistic effects of chemotherapy and PTT. Furthermore, the potential for synergistic fluorescence imaging-guided chemo-phototherapy in cancer treatment is illustrated. Thus, this work exemplifies the development of biosafe, multifunctional JNPs for advanced applications in cancer theranostics. STATEMENT OF SIGNIFICANCE: Facile fabrication of monodispersed nanomedicine with multi-cancer killing modalities organically integrated is nontrivial and becomes more challenging under the biocompatibility requirement that is necessary for the practical applications of nanomedicines. In this study, we creatively designed PAA-mZnP/PDA JNPs and fabricated them under mild conditions. Our method reliably yields uniform JNPs with excellent monodispersity. To maximize functionalities, we achieve fourfold advantages including efficient drug/fluorescent dye loading, PTT, pH/NIR dual-responsive properties, and optimal biocompatibility. The as-fabricated JNPs exhibit satisfactory anti-cancer performance both in vitro and in vivo, and demonstrate the potential of JNPs in fluorescence imaging-guided synergistic cancer chemo-phototherapy. Overall, our research establishes a pathway in versatile inorganic/polymer JNPs for enhanced cancer diagnosis and therapy.

The Internalization Pathways of Liposomes, PLGA, and Magnetic Nanoparticles in Neutrophils

BACKGROUND/OBJECTIVES

Neutrophils are emerging as promising candidates for cell-based nanodrug delivery to tumors due to their unique biological properties. This study aims to investigate the mechanisms of nanoparticle internalization by neutrophils, specifically focusing on liposomes, poly(lactic-co-glycolic acid) (PLGA), and magnetite nanoparticles. Understanding these mechanisms could enhance the efficiency of neutrophil-based nanodrug delivery for cancer treatment.

METHODS

Neutrophils were isolated from the peripheral blood of mice bearing 4T1 mammary adenocarcinoma. Confocal microscopy, transmission electron microscopy, and flow cytometry were employed to evaluate the uptake of liposomes, PLGA, and magnetite nanoparticles by neutrophils. The effects of cultivation conditions, such as the presence or absence of plasma in the growth medium, were also examined. Additionally, the roles of immunoglobulins (IgG/IgM) and cell surface receptors (Fc and scavenger receptors) in nanoparticle internalization were explored.

RESULTS

All types of nanoparticles were successfully internalized by neutrophils, though the mechanisms of uptake varied. Plasma presence in the medium significantly influenced nanoparticle binding, particularly for PLGA nanoparticles. Internalization of PLGA nanoparticles was found to depend on the presence of IgG/IgM in the medium and Fc receptors on neutrophil surfaces, while scavenger receptors were not involved.

CONCLUSIONS

Understanding the distinct endocytosis pathways for different nanoparticles can improve the efficacy of neutrophil loading with nanodrugs, potentially advancing the development of neutrophil-based cancer therapies. The findings underscore the importance of the extracellular environment in modulating nanoparticle uptake.

Cellular Output and Physicochemical Properties of the Membrane-Derived Vesicles Depend on Chemical Stimulants

Synthetic liposomes are widely used as drug delivery vehicles in biomedical treatments, such as for mRNA-based antiviral vaccines like those recently developed against SARS-CoV-2. Extracellular vesicles (EVs), which are naturally produced by cells, have emerged as a next-generation delivery system. However, key questions regarding their origin within cells remain unresolved. In this regard, plasma membrane vesicles (PMVs), which are essentially produced from the cellular plasma membrane (PM), present a promising alternative. Unfortunately, their properties relevant to biomedical applications have not be extensively studied. Therefore, we conducted a thorough investigation of the methods used in the production of PMVs. By leveraging advanced fluorescence techniques in microscopy and flow cytometry, we demonstrated a strong dependence of the physicochemical attributes of PMVs on the chemicals used during their production. Following established protocols employing chemicals such as paraformaldehyde (PFA), N-ethylmaleimide (NEM) or dl-dithiothreitol (DTT) and by developing a modified NEM-based method that involved a hypotonic shock step, we generated PMVs from THP-1 CD1d cells. We systematically compared key parameters such as vesicle output, their size distribution, vesicular content analysis, vesicular membrane lipid organization and the mobility of a transmembrane protein. Our results revealed distinct trends: PMVs isolated using NEM-based protocols closely resembled natural vesicles, whereas PFA induced significant molecular cross-linking, leading to notable changes in the biophysical properties of the vesicles. Furthermore, our novel NEM protocol enhanced the efficiency of PMV production. In conclusion, our study highlights the unique characteristics of chemically produced PMVs and offers insights into their potentially diverse yet valuable biological functions.

Endothelial extracellular vesicles enhance vascular self-assembly in engineered human cardiac tissues

The fabrication of complex and stable vasculature in engineered cardiac tissues represents a significant hurdle towards building physiologically relevant models of the heart. Here, we implemented a 3D model of cardiac vasculogenesis, incorporating endothelial cells (EC), stromal cells, and human induced pluripotent stem cell (iPSC)-derived cardiomyocytes (CM) in a fibrin hydrogel. The presence of CMs disrupted vessel formation in 3D tissues, resulting in the upregulation of endothelial activation markers and altered extracellular vesicle (EV) signaling in engineered tissues as determined by the proteomic analysis of culture supernatant. miRNA sequencing of CM- and EC-secreted EVs highlighted key EV-miRNAs that were postulated to play differing roles in cardiac vasculogenesis, including the let-7 family and miR-126-3p in EC-EVs. In the absence of CMs, the supplementation of CM-EVs to EC monolayers attenuated EC migration and proliferation and resulted in shorter and more discontinuous self-assembling vessels when applied to 3D vascular tissues. In contrast, supplementation of EC-EVs to the tissue culture media of 3D vascularized cardiac tissues mitigated some of the deleterious effects of CMs on vascular self-assembly, enhancing the average length and continuity of vessel tubes that formed in the presence of CMs. Direct transfection validated the effects of the key EC-EV miRNAs let-7b-5p and miR-126-3p in improving the maintenance of continuous vascular networks. EC-EV supplementation to biofabricated cardiac tissues and microfluidic devices resulted in tissue vascularization, illustrating the use of this approach in the engineering of enhanced, perfusable, microfluidic models of the myocardium.

Therapeutic potential of RNA-enriched extracellular vesicles: The next generation in RNA delivery via biogenic nanoparticles

Exosomes are extracellular vesicles (EVs) (∼50-150 nm) that have emerged as promising vehicles for therapeutic applications and drug delivery. These membrane-bound particles, released by all actively dividing cells, have the ability to transfer effector molecules, including proteins, RNA, and even DNA, from donor cells to recipient cells, thereby modulating cellular responses. RNA-based therapeutics, including microRNAs, messenger RNAs, long non-coding RNAs, and circular RNAs, hold great potential in controlling gene expression and treating a spectrum of medical conditions. RNAs encapsulated in EVs are protected from extracellular degradation, making them attractive for therapeutic applications. Understanding the intricate biology of cargo loading and transfer within EVs is pivotal to unlocking their therapeutic potential. This review discusses the biogenesis and classification of EVs, methods for loading RNA into EVs, their advantages as drug carriers over synthetic-lipid-based systems, and the potential applications in treating neurodegenerative diseases, cancer, and viral infections. Notably, EVs show promise in delivering RNA cargo across the blood-brain barrier and targeting tumor cells, offering a safe and effective approach to RNA-based therapy in these contexts.

Unveiling Invisible Extracellular Vesicles: Cutting-Edge Technologies for Their in Vivo Visualization

Extracellular vesicles (EVs), nanosized lipid bilayer vesicles released by nearly all types of cells, play pivotal roles as intercellular signaling mediators with diverse biological activities. Their adaptability has attracted interest in exploring their role as disease biomarker theranostics. However, the in vivo biodistribution and pharmacokinetic profiles of EVs, particularly following administration into living subjects, remain unclear. Thus, in vivo imaging is vital to enhance our understanding of the homing and retention patterns, blood and tissue half-life, and excretion pathways of exogenous EVs, thereby advancing real-time monitoring within biological systems and their therapeutic applications. This review examines state-of-the-art methods including EV labeling with various agents, including optical imaging, magnetic resonance imaging, and nuclear imaging. The strengths and weaknesses of each technique are comprehensively explored, emphasizing their clinical translation. Despite the potential of EVs as cancer theranostics, achieving a thorough understanding of their in vivo behavior is challenging. This review highlights the urgency of addressing current questions in the biology and therapeutic applications of EVs. It underscores the need for continued research to unravel the complexities surrounding EVs and their potential clinical implications. By identifying these challenges, this review contributes to ongoing efforts to optimize EV imaging techniques for clinical use. Ultimately, bridging the gap between research advancements and clinical applications will facilitate the integration of EV-based theranostics, marking a crucial step toward harnessing the full potential of EVs in medical practice.

Antioxidant Carbon Dots and Ursolic Acid Co-Encapsulated Liposomes Composite Hydrogel for Alleviating Adhesion Formation and Enhancing Tendon Healing in Tendon Injury

Background

The formation of adhesion after tendon injury represents a major obstacle to tendon repair, and currently there is no effective anti-adhesion method in clinical practice. Oxidative stress, inflammation, and fibrosis can occur in tendon injury and these factors can lead to tendon adhesion. Antioxidant carbon dots and ursolic acid (UA) both possess antioxidant and anti-inflammatory properties. In this experiment, we have for the first time created RCDs/UA@Lipo-HAMA using red fluorescent carbon dots and UA co-encapsulated liposomes composite hyaluronic acid methacryloyl hydrogel. We found that RCDs/UA@Lipo-HAMA could better attenuate adhesion formation and enhance tendon healing in tendon injury.

Materials and Methods

RCDs/UA@Lipo-HAMA were prepared and characterized. In vitro experiments on cellular oxidative stress and fibrosis were performed. Reactive oxygen species (ROS), and immunofluorescent staining of collagens type I (COL I), collagens type III (COL III), and α-smooth muscle actin (α-SMA) were used to evaluate anti-oxidative and anti-fibrotic abilities. In vivo models of Achilles tendon injury repair (ATI) and flexor digitorum profundus tendon injury repair (FDPI) were established. The major organs and blood biochemical indicators of rats were tested to determine the toxicity of RCDs/UA@Lipo-HAMA. Biomechanical testing, motor function analysis, immunofluorescence, and immunohistochemical staining were performed to assess the tendon adhesion and repair after tendon injury.

Results

In vitro, the RCDs/UA@Lipo group scavenged excessive ROS, stabilized the mitochondrial membrane potential (ΔΨm), and reduced the expression of COL I, COL III, and α-SMA. In vivo, assessment results showed that the RCDs/UA@Lipo-HAMA group improved collagen arrangement and biomechanical properties, reduced tendon adhesion, and promoted motor function after tendon injury. Additionally, the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase 1 (HO-1) in the RCDs/UA@Lipo-HAMA group increased; the levels of cluster of differentiation 68 (CD68), inducible Nitric Oxide Synthase (iNOS), COL III, α-SMA, Vimentin, and matrix metallopeptidase 2 (MMP2) decreased.

Conclusion

In this study, the RCDs/UA@Lipo-HAMA alleviated tendon adhesion formation and enhanced tendon healing by attenuating oxidative stress, inflammation, and fibrosis. This study provided a novel therapeutic approach for the clinical treatment of tendon injury.

T Cell-Derived Apoptotic Extracellular Vesicles Hydrolyze cGAMP to Alleviate Radiation Enteritis via Surface Enzyme ENPP1

Radiation enteritis is the most common complication of pelvic radiotherapy, but there is no effective prevention or treatment drug. Apoptotic T cells and their products play an important role in regulating inflammation and maintaining physiological immune homeostasis. Here it is shown that systemically infused T cell-derived apoptotic extracellular vesicles (ApoEVs) can target mice irradiated intestines and alleviate radiation enteritis. Mechanistically, radiation elevates the synthesis of intestinal 2'3' cyclic GMP-AMP (cGAMP) and activates cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) proinflammatory pathway. After systemic infusion of ApoEVs, the ectonucleotide pyrophosphatase phosphodiesterase 1 (ENPP1) enriches on the surface of ApoEVs hydrolyze extracellular cGAMP, resulting in inhibition of the cGAS-STING pathway activated by irradiation. Furthermore, after ApoEVs are phagocytosed by phagocytes, ENPP1 on ApoEVs hydrolyzed intracellular cGAMP, which serves as an intracellular cGAMP hydrolyzation mode, thereby alleviating radiation enteritis. The findings shed light on the intracellular and extracellular hydrolysis capacity of ApoEVs and their role in inflammation regulation.

Surface functionalization of virus-like particles via bioorthogonal click reactions for enhanced cell-specific targeting

Surface functionalization of nano drug carriers allows for precise delivery of therapeutic molecules to the target site. This technique involves attaching targeting molecules to the nanoparticle surface, facilitating selective interaction. In this study, we engineered virus-like particles (VLPs) to enhance their targeting capabilities. Azide groups incorporated on the lipid membranes of VLPs enabled bioorthogonal click reactions for conjugation with cycloalkyne-bearing molecules, providing efficient conjugation with high specificity. HIV-1 Gag VLPs were chosen due to their envelope, which allows host membrane component incorporation, and the Gag protein, which serves as a recognition motif for human T cells. This combination, along with antibody-mediated targeting, addresses the limitations of intracellular delivery to T cells, which typically exhibit low uptake of exogenous materials. The selective uptake of azide VLPs by CD3-positive T cells was evaluated in a co-culture system. Even without antibody conjugation, VLP uptake was enhanced in T cells, indicating their intrinsic targeting potential. Antibody conjugation further amplified this effect, demonstrating the synergistic benefits of the combined targeting approach. Our study shows that recombinant production of azide functionalized VLPs results in engineered nanoparticles that can be easily modified using bioorthogonal click reactions, providing high specificity and versatility for conjugation with various molecules, making it applicable to a wide range of biological products.

Liposomes Loaded with 5-Fluorouracil Can Improve the Efficacy in Pathological Scars

Introduction

Pathological scars, such as hypertrophic scars and keloids, are characterized by the proliferation of fibroblasts and the deposition of collagen that often cause pruritus, pain, and disfigurement. Due to their high incidence and deformity, pathological scars have resulted in severe physical and psychological trauma for patients. Intralesional injection of 5-fluorouracil (5-Fu) is a recommended option for treating pathological scars. However, the efficacy of 5-Fu injection was limited and unstable due to limited drug penetration and short retention time.

Methods

Liposomes are promising carriers that have advantages, such as high biocompatibility, controlled release property, and enhanced clinical efficacy. Here, we constructed a transdermal 5-Fu-loaded liposome (5-Fu-Lip) to provide a more effective and safer modality to scar treatment.

Results

Compared to 5-Fu, 5-Fu-Lip showed superior ability in inhibiting primary keloid fibroblasts proliferation, migration, and collagen deposition, and also significantly inhibited human umbilical vein endothelial cells (HUVECs) proliferation and microvessel construction. In vivo experiments demonstrated that 5-Fu-Lip can significantly reduce the severity of hypertrophic scars in a rabbit ear wounding model.

Discussion

5-Fu-Lip provides a promising strategy to improve drug efficacy, which has great potential in the treatment of pathological scars.

A Systematic Review on Plant-Derived Extracellular Vesicles as Drug Delivery Systems

This systematic review offers a comprehensive analysis of plant-derived extracellular vesicles (PDEVs) as emerging drug delivery systems, focusing on original research articles published between 2016 and 2024 that exclusively examine the use of PDEVs for drug delivery. After a rigorous search across multiple databases, 20 relevant studies out of 805 initial results were selected for analysis. This review systematically summarizes the critical data on PDEV components, isolation methods, and drug-loading techniques. It highlights the potential of PDEVs to significantly enhance drug safety and efficacy, reduce dosage and toxicity, and align drug development with sustainable and environmentally friendly biotechnological processes. This review also emphasizes the advantages of PDEVs over mammalian-derived vesicles, such as cost-effectiveness, higher yield, and reduced immunogenicity. Additionally, it explores the synergistic potential between encapsulated drugs and bioactive compounds naturally present in PDEVs. This study acknowledges the challenges in standardizing isolation and formulation methods for clinical use. Overall, this review provides valuable insights into the current state and future directions of PDEV-based drug delivery systems, highlighting their promising role in advancing pharmaceutical research and development.

Differentially Charged Liposomes Stimulate Dendritic Cells with Varying Effects on Uptake and Processing When Used Alone or in Combination with an Adjuvant

Liposomes carrying differential charges have been extensively studied for their role in stimulating dendritic cells (DCs), major antigen-presenting cells, known to serve as a pivotal bridge between innate and adaptive immunity. However, the impact of the differentially charged liposomes on activating DCs remains to be understood. In this study, we have investigated the impact of 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC)-based neutral, anionic, and cationic liposomes on the uptake, immunostimulation, and intracellular fate in mouse bone-marrow-derived DCs. We observed that liposomes could induce phenotypic maturation of DCs by inducing the expression of costimulatory molecules (CD40 and CD86) and production of cytokines tumor necrosis factor-α, interleukin-12,and nitric oxide. Interestingly, admixing monophosphoryl lipid A with charged liposomes further enhances the expression of the costimulatory molecules and production of cytokines, with preferential activation by positively charged liposomes. Fluorometric analysis using a pH-sensitive dye and flow-cytometry-based pathway inhibition assays revealed that cationic liposomes were taken up more efficiently by DCs through endocytosis and transported to neutral compartments for further processing, whereas anionic and neutral liposomes were inclined to accumulate in acidic compartments. These findings therefore endorse the use of cationic DSPC liposomes as a preferred option for vaccine delivery vehicles over neutral and negatively charged liposomes, particularly for the preferential activation of DCs.

Endosomal escape mechanisms of extracellular vesicle-based drug carriers: lessons for lipid nanoparticle design

The rise of biologics and RNA-based therapies challenges the limitations of traditional drug treatments. However, these potent new classes of therapeutics require effective delivery systems to reach their full potential. Lipid nanoparticles (LNPs) have emerged as a promising solution for RNA delivery, but endosomal entrapment remains a critical barrier. In contrast, natural extracellular vesicles (EVs) possess innate mechanisms to overcome endosomal degradation, demonstrating superior endosomal escape (EE) compared to conventional LNPs. This mini review explores the challenges of EE for lipid nanoparticle-based drug delivery, and offers insights into EV escape mechanisms to advance LNP design for RNA therapeutics. We compare the natural EE strategies of EVs with those used in LNPs and highlight contemporary LNP design approaches. By understanding the mechanisms of EE, we will be able to develop more effective drug delivery vehicles, enhancing the delivery and efficacy of RNA-based therapies.