Delivery Of Vesicles Research Articles

Simultaneous ischemic regions targeting and BBB crossing strategy to harness extracellular vesicles for therapeutic delivery in ischemic stroke

Extracellular vesicles (EVs) derived from adipose-derived stem cells (ADSC-EVs) hold great promise for ischemic stroke treatment, but their therapeutic efficacy is greatly limited due to insufficient targeting ability. Previous reports focused on single ischemic targeting or blood-brain barrier (BBB) penetration, precise delivery to the brain parenchyma has not been fully considered. This study leveraged the targeting ability of RGD peptide and the cell penetrating ability of Angiopep-2 peptide to deliver ADSC-EVs precisely to the impaired brain parenchyma. We found that dual-modified EVs (RA-EVs) significantly enhanced the transcellular permeability across BBB in vitro, and not only targeted ischemic blood vessels but also achieved rapid accumulation in the ischemic lesion area after intravenous administration in vivo. RA-EVs further decreased the infarct volume, apoptosis, BBB disruption, and neurobehavioral deficits. RNA sequencing revealed the molecular regulation mechanism after administration. These findings demonstrate that dual-modification optimizes brain parenchymal targeting and highlights the significance of recruitment and penetration as a previously unidentified strategy for harnessing EVs for therapeutic delivery in ischemic stroke.

Preclinical pharmacology of patient-derived extracellular vesicles for the intraoperative imaging of tumors.

Extracellular vesicles (EVs) derived from the plasma of oncological patients exhibit significant tumor-targeting properties, unlike those from healthy individuals. We have previously shown the feasibility of formulating the near-infrared (NIR) fluorescent dye indocyanine green (ICG) with patient-derived extracellular vesicles (PDEVs) for selective delivery to neoplastic tissue. This staining protocol holds promise for clinical application in intraoperative tumor margin imaging, enabling precise neoplastic tissue resection. To this end, we propose the ONCOGREEN protocol, involving PDEV isolation, ICG loading, and reinfusion into the same patients. Methods: By in vivo studies on mice, we outlined key pharmacological parameters of PDEVs-ICG for intraoperative tumor imaging, PDEV biodistribution kinetics, and potential treatment-related toxicological effects. Additionally, we established a plasmapheresis-based protocol for isolating autologous PDEVs, ensuring the necessary large-scale dosage for human treatment. A potential lyophilization-based preservation method was also explored to facilitate the storage and transport of PDEVs. Results: The study identified the effective dose of PDEVs-ICG necessary for clear intraoperative tumor margin imaging. The biodistribution kinetics of PDEVs showed favorable targeting to neoplastic tissues, without off-target distribution. Toxicological assessments revealed no significant adverse effects associated with the treatment. The plasmapheresis-based isolation protocol successfully yielded a sufficient quantity of autologous PDEVs, and the lyophilization preservation method maintained the functional integrity of PDEVs for subsequent clinical application. Conclusions: Our research lays the groundwork for the direct clinical application of autologous PDEVs, initially focusing on intraoperative imaging. Utilizing autologous PDEVs has the potential to accelerate the integration of EVs as a targeted delivery tool for anti-neoplastic agents to cancerous tissue. This approach promises to enhance the precision of neoplastic tissue resection and improve overall surgical outcomes for oncological patients.

Vesicle delivery systems of functional substances for precision nutrition.

Vesicular delivery systems are highly ordered assemblies consisting of one or more concentric bilayers formed by the self-assembly of amphiphilic building blocks in the presence of water. In the field of functional food, vesicular delivery systems have been widely explored for effective formulations to deliver functional substances. With the effort of scientific research, certain categories of vesicular delivery systems have successfully been translated from the laboratory to the global market of functional food. This chapter aims to present comprehensively the various vesicular delivery systems, including their design, preparation methods, encapsulation of functional substances, and application in nutritional interventions.

Poly (vinyl alcohol)-gelatin-sericin copolymerized film fortified with vesicle-entrapped demethoxycurcumin/bisdemethoxycurcumin for improved stability, antibacterial, anti-inflammatory, and skin tissue regeneration

Vesicle delivery carriers, used to stabilize hydrophobic drugs, are characterized by the propensity to aggregate, and fuse, limiting its applications. Fortifying vesicle-entrapped drugs within a biodegradable polymeric film constitutes a promising solution. In this study, biodegradable poly (vinyl alcohol) copolymerized with gelatin-sericin film and integrated alongside vesicle-entrapped demethoxycurcumin (DMC) or bisdemethoxycurcumin (BDMC) was developed, extensively characterized for improve efficacy, and compared. Vesicle-entrapped DMC or BDMC was spherical in shape with no changes in size, zeta-potential, and morphology after storing at 4 °C for 30 days. Antibacterial activity of vesicle-entrapped DMC formulations against Acinetobacter baumannii and Staphylococcus epidermidis was more effective than that of its free form. DMC and BDMC demonstrated dose dependent reduction in lipopolysaccharides (LPS)-induced nitric oxide (NO) levels either in free or in entrapped form. Moreover, vesicle-entrapped DMC/BDMC suppressed NO production at lower concentrations, compared with that of their free form and significantly improved the viability of RAW264.7 and HaCaT cells. Furthermore, functionalized film with vesicle-entrapped DMC/BDMC demonstrated excellent radical scavenging, biocompatibility, and cell migration efficacy. Thus, incorporating vesicle, entrapped DMC/BDMC within biodegradable polymeric film may comprised a promising strategy for improving stability, wound healing, and inflammation attenuation efficacy.

Dual-functional DNA nanogels for anticancer drug delivery

DNA hydrogels with unique sequence programmability on nucleic acid framework manifest remarkable attributes, such as high payload capacities, biocompatibility and biosafety. The availability of DNA nanogels with multimodal functionalities remains limited due to the absence of facile gelation methods applicable at the nanometer scale. Here, we developed a one-step assembly of DNA dendrimers into nanogels (DNG) with couple hundred nanometers size. DNG showed robust stability against physical forces and biological degradation for easy purification and sustainable drug release. Long-term stability either in powder or aqueous solution endows DNG easy for shipping, handling and storage. By encoding dual functionalities into separate branches on DNA dendrimers, DNG can accommodate chemodrugs and aptamers with distinctive loading moduli. DNG significantly enhanced the drug efficacy against cancerous cells while minimizing cytotoxicity towards somatic cells, as demonstrated in vitro and in xenografted mice models of breast cancer. Thus, due to their facile assembly and storage, bi-entity encoding, and inherent biocompatibility, DNG exhibits immense prospects as nanoscale vesicles for the synergistic delivery of multimodal theranostics in anticancer treatments. Statement of significanceDNA nanogels were self-assembled via a facile protocol utilizing a DNA dendrimer structure. These nanogels displayed robust stability against physical forces, permitting long term storage in concentrated solutions or as a powder. Furthermore, they exhibited resilience to biological degradation, facilitating sustained drug release. The bi-entity encoded dendritic branches conferred dual functionalities, enabling both chemodrug encapsulation and the presentation of aptamers as targeting motifs. In vivo investigations confirmed the nanogels provide high efficacy in tumor targeting and chemotherapy with enhanced drug efficacy and reduced side effects.

Electrospinning polymersomes into bead-on-string polyethylene oxide fibres for the delivery of biopharmaceuticals to mucosal epithelia

Fibrous mucoadhesive polymer membranes prepared using electrospinning demonstrate many advantages for mucosal drug delivery compared to other formulations. Previous electrospun membrane formulations have been developed mainly for the delivery of small molecule drugs. There remains great potential to further develop the technology for the delivery of vesicular vectors that allow administration of advanced therapeutic agents. However, there are no previous reports demonstrating the release of intact drug delivery vesicles from electrospun materials. Here, we describe incorporation and release of protein-loaded polymersomes from polyethylene oxide (PEO)-based electrospun membranes. Polymersomes comprising a copolymer of glycerol monomethacrylate (GMA) and hydroxypropyl methacrylate (HPMA) were prepared using polymerization-induced self-assembly and incorporated within PEO membranes using bead-on-string electrospinning at approximately 40 % w/w by polymer mass. Super-resolution fluorescence imaging showed that the vesicles remained intact and retained their encapsulated protein load within the fibre beads. Transmission electron microscopy and dynamic light scattering demonstrated that polymersomes retained their morphology following release from the polymer fibres. F(ab) antibody fragments were encapsulated within polymersomes and then electrospun into membranes. 78 ± 13 % of the F(ab) remained encapsulated within polymersomes during electrospinning and retained functionality when released from electrospun membranes, demonstrating that the formulation is suitable for the delivery of biologics. Membranes were non-irritant to the oral epithelium and fluorescence microscopy detected accumulation of polymersomes within the epithelia following application. This innovative drug delivery approach represents a novel and potentially highly useful method for the administration of large molecular mass therapeutic molecules to diseased mucosal sites.

Penetration enhancer containing vesicles for dermal and transdermal drug delivery. A review.

Penetration enhancer containing vesicles for dermal and transdermal drug delivery. A review.

Development of the cholestosome, a novel delivery system made exclusively from cholesteryl esters

AbstractA novel vesicular drug delivery system has been created using only cholesteryl esters. The uncharged nature of the esters requires a formulation process that uses energy, in the form of sonication, to facilitate the cholesteryl esters formation into vesicles. The nature of the material choices renders the vesicles resistant to pH degradation between a pH of 2 and 10. Storage condition at 4°C for 9 months shows a stability of encapsulated materials as well as vesicles. The formulation process is a modified reverse phase method in which the esters are dissolved in an organic solvent, which is then removed and the aqueous component is then added with sonication in a temperature‐controlled water bath. A wide variety of materials can be encapsulated in these vesicles, which are called cholestosomes. Delivery of the cholestosome‐encapsulated materials is a function of the ester component structure and not the encapsulated molecule. Once encapsulated, the vesicles deliver the materials into cells. The potential for oral availability was explored using chylomicrons. Successful delivery of the cholestosome encapsulated into chylomicrons has enhanced the effectiveness of delivery to cells. Analytical methods have been developed to analyze the materials chosen from the cholesteryl esters as well as the encapsulated materials.Practical Applications: The creation of the cholestosome vesicle opens up completely new areas for encapsulating and delivering materials. The cholesteryl ester structure that makes up the vesicles is impervious to pH and bile salts, making cholestosomes ideal for oral delivery of drugs, such as oral insulin. Intracellular delivery of cholestosome vesicles enables multiple applications, from killing latent infections to preventing viral replication (irrespective of the virus) and delivering nucleic acid therapeutics to cure genetic disease. These vesicles pass the blood–brain barrier and could be used for treatments of Alzheimer's and related neurodegenerative disease. Cholestosomes can also be used in cosmetic formulations as the vesicles pass the dermis. They even could be used in food applications as the materials are considered generally regarded as safe.

Refining Immunogenicity through Intradermal Delivery of Outer Membrane Vesicles against Shigella flexneri in Mice

Shigellosis remains a global health concern, especially in low- and middle-income countries. Despite improvements in sanitation, the absence of a licensed vaccine for human use has prompted global health organizations to support the development of a safe and effective multivalent vaccine that is cost-effective and accessible for limited-resource regions. Outer Membrane Vesicles (OMVs) have emerged in recent years as an alternative to live attenuated or whole-inactivated vaccines due to their immunogenicity and self-adjuvating properties. Previous works have demonstrated the safety and protective capacity of OMVs against Shigella flexneri infection in mouse models when administered through mucosal or intradermal routes. However, some immunological properties, such as the cellular response or cross-protection among different Shigella strains, remained unexplored. In this study, we demonstrate that intradermal immunization of OMVs with needle-free devices recruits a high number of immune cells in the dermis, leading to a robust cellular response marked by antigen-specific cytokine release and activation of effector CD4 T cells. Additionally, functional antibodies are generated, neutralizing various Shigella serotypes, suggesting cross-protective capacity. These findings highlight the potential of OMVs as a promising vaccine platform against shigellosis and support intradermal administration as a simple and painless vaccination strategy to address this health challenge.

Harnessing small extracellular vesicles for pro-oxidant delivery: novel approach for drug-sensitive and resistant cancer therapy

Multidrug resistance (MDR) is an inevitable clinical problem in chemotherapy due to the activation of abundant P-glycoprotein (P-gp) that can efflux drugs. Limitations of current cancer therapy highlight the need for the development of a comprehensive cancer treatment strategy, including drug-resistant cancers. Small extracellular vesicles (sEVs) possess significant potential in surmounting drug resistance as they can effectively evade the efflux mechanism and transport small molecules directly to MDR cancer cells. One mechanism mediating MDR in cancer cells is sustaining increased levels of reactive oxygen species (ROS) and maintenance of the redox balance with antioxidants, including glutathione (GSH). Herein, we developed GSH-depleting benzoyloxy dibenzyl carbonate (B2C)-encapsulated sEVs (BsEVs), which overcome the efflux system to exert highly potent anticancer activity against human MDR ovarian cancer cells (OVCAR-8/MDR) by depleting GSH to induce oxidative stress and, in turn, apoptotic cell death in both OVCAR-8/MDR and OVCAR-8 cancer cells. BsEVs restore drug responsiveness by inhibiting ATP production through the oxidation of nicotinamide adenine dinucleotide with hydrogen (NADH) and inducing mitochondrial dysfunction, leading to the dysfunction of efflux pumps responsible for drug resistance. In vivo studies showed that BsEV treatment significantly inhibited the growth of OVCAR-8/MDR and OVCAR-8 tumors. Additionally, OVCAR-8/MDR tumors showed a trend towards a greater sensitivity to BsEVs compared to OVCAR tumors. In summary, this study demonstrates that BsEVs hold tremendous potential for cancer treatment, especially against MDR cancer cells.

Biofunctional coacervate-based artificial protocells with membrane-like and cytoplasm-like structures for the treatment of persistent hyperuricemia

Coacervate droplets formed by liquid-liquid phase separation have attracted considerable attention due to their ability to enrich biomacromolecules while preserving their bioactivities. However, there are challenges to develop coacervate droplets as delivery vesicles for therapeutics resulting from the lack of physiological stability and inherent lack of membranes in coacervate droplets. Herein, polylysine-polynucleotide complex coacervate droplets with favorable physiological stability are formulated to efficiently and facilely concentrate small molecules, biomacromolecules and nanoparticles without organic solvents. To improve the biocompatibility, the PEGylated phospholipid membrane is further coated on the surface of the coacervate droplets to prepare coacervate-based artificial protocells (ArtPC) with membrane-like and cytoplasm-like structures. The ArtPC can confine the cyclic catalytic system of uricase and catalase inside to degrade uric acid and deplete the toxicity of H2O2. This biofunctional ArtPC effectively reduces blood uric acid levels and prevents renal injuries in mice with persistent hyperuricemia. The ArtPC-based therapy can bridge the disciplines of synthetic biology, pharmaceutics and therapeutics.

Probing milk extracellular vesicles for intestinal delivery of RNA therapies

BackgroundOral delivery remains unattainable for nucleic acid therapies. Many nanoparticle-based drug delivery systems have been investigated for this, but most suffer from poor gut stability, poor mucus diffusion and/or inefficient epithelial uptake. Extracellular vesicles from bovine milk (mEVs) possess desirable characteristics for oral delivery of nucleic acid therapies since they both survive digestion and traverse the intestinal mucosa.ResultsUsing novel tools, we comprehensively examine the intestinal delivery of mEVs, probing whether they could be used as, or inform the design of, nanoparticles for oral nucleic acid therapies. We show that mEVs efficiently translocate across the Caco-2 intestinal model, which is not compromised by treatment with simulated intestinal fluids. For the first time, we also demonstrate transport of mEVs in novel 3D ‘apical-out’ and monolayer-based human intestinal epithelial organoids (IEOs). Importantly, mEVs loaded with small interfering RNA (siRNA) induced (glyceraldehyde 3-phosphate dehydrogenase, GAPDH) gene silencing in macrophages. Using inflammatory bowel disease (IBD) as an example application, we show that administration of anti-tumour necrosis factor alpha (TNFα) siRNA-loaded mEVs reduced inflammation in a IBD rat model.ConclusionsTogether, this work demonstrates that mEVs could either act as natural and safe systems for oral delivery or nucleic acid therapies, or inform the design of synthetic systems for such application.Graphical

Targeted Delivery of IL-12 Via CD19-Modified Extracellular Vesicles Enhances CAR-T Cell Efficacy Against Lymphoma

Introduction Chimeric Antigen Receptor T-Cell (CAR-T cell) Therapy faces challenges related to low potency and poor in vivo persistence. Incorporating cytokine signals, such as interleukin-12 (IL-12), has emerged as a promising strategy to enhance CAR-T cell functionality due to its potent immunostimulatory effects. However, clinical application of IL-12 is hindered by pleiotropic toxicity and limited bioavailability. Therefore, alternative agents or delivery systems are desired to exploit the benefits of IL-12 safely. This study investigated the therapeutic potential of a novel IL-12 delivery system utilizing extracellular vesicles (EVs) modified with the target antigen CD19 to specifically deliver IL-12 to CD19 CAR-T cells, thus augmenting their anti-tumor effects. Method IL-12-anchored extracellular vesicles (IL-12 EVs) were generated from engineered 293T cells expressing IL-12 on the cell membrane via GPI structure. Additionally, EVs co-expressing IL-12 and CD19 (CD19/IL-12 EVs) were produced from 293T cells co-expressing CD19 and IL-12. The physicochemical characteristics of the EVs were analyzed using nanoparticle tracking analysis (NTA), transmission electron microscopy (TEM), and western blot (WB). Binding and uptake efficiency of the EVs with CD19 CAR-T cells were validated using flow cytometry and imaging flow cytometry. In vitro experiments were conducted to investigate the effects of the EVs on the cytotoxic function, degranulation, cytokine secretion, and proliferation of CD19 CAR-T cells. Furthermore, the therapeutic efficacy and safety of CD19 CAR-T cells combined with intratumoral injection of IL-12 EVs were evaluated in a mouse model of Raji lymphoma xenograft. Result HEK293T cell-derived, IL-12-bearing EVs were successfully prepared. IL-12 on the surface of EVs was quantified by enzyme-linked immunosorbent assay. IL-12 EVs promoted interferon-γ secretion of co-cultured CAR-T cells in a dose-dependent manner, reaching a peak at a concentration of about 1 ng/mL of IL-12 EVs. At this concentration, IL-12 EVs significantly enhanced CAR-T cell cytotoxicity while recombinant human interleukin-12 not. Co-expressing CD19 and IL-12 EVs were prepared and visualized by imaging flow cytometry, showing the presence of both IL-12 and CD19 on the surface of each individual EV. CD19/IL-12 EVs exhibited stronger tropism towards anti-CD19 CAR-T cells than IL-12 EVs (Figure 1). Similarly, CD19/IL-12 EVs could promote CAR-T cells with increased cytokine secretion and improved tumor-killing ability. In a Raji subcutaneous lymphoma xenograft mouse model, intratumoral injection of CD19/IL-12 EVs observably promoted CAR-T cell function, achieved superior proliferation and enhanced anti-tumor effects without systemic toxicity (Figure 2). Conclusion This study demonstrated that surface modification of EVs with target antigens empowers EVs with improved CAR-T cell targeting, creating an effective delivery platform for targeted delivery of bioactive molecules, such as IL-12, to CAR-T cells, thereby enhancing immunotherapeutic efficacy.

Novel Bone Marrow/HSC-Targeted, Megakaryocyte-Derived Extracellular Vesicle Delivery Modality for In Vivo Gene Therapy

Gene therapy lacks tools to deliver in a safe and tissue-targeted manner. Limitations include toxicity, off-target effects due to targeting, and inability to repeat dose. We have developed a novel megakaryocyte-derived extracellular vesicle (MkEV)-based non-viral gene therapy delivery platform that preferentially targets bone marrow in vivo. Here we present work showing that STRM.BIO MkEVs: 1) pass through the liver and spleen to preferentially target bone marrow in mice and non-human primates (NHPs); 2) can selectively deliver pDNA cargo to long term HSCs to drive reporter protein expression exclusively in bone marrow following intravenous delivery in mice; and 3) present a platform to develop and deliver targeted gene therapies in vivo that are safe for repeat dosing. Our vision is to open the door to the future of medicine for patients living with rare diseases worldwide and bring gene therapy to life. Primary human CD34+ hematopoietic stem and progenitor cells (hHSPCs) were differentiated into megakaryocytes in vitro. MkEVs were harvested and loaded with pDNA via electroporation, followed by DNase treatment to remove free cargo. For in vivo biodistribution and cargo-mediated protein expression studies, STRM.BIO MkEVs were exogenously labeled with fluorescent dye (PKH26, Cell Tracker Deep Red, and/or DiD), loaded with cargo, and IV-injected into mouse tail veins (wild type or NSG) or NHPs (cynomolgus monkeys). Tissues were collected 16-48h after IV injection, with MkEV tissue biodistribution quantified by dye fluorescence (Mean Fluorescence Intensity (MFI), plate reader) normalized to tissue weight or genomic DNA input, and pDNA cargo quantified by qPCR. Additionally, quantification of MkEVs+ cells was performed by flow cytometry analysis of murine bone marrow derived sub-populations (lineage negative, c-Kit +, Sca-1 + (LSK); lineage positive (Lin +); and, long-term HSCs (LT-HSCs; Lin -/CD150 +/CD201 +)) cells. Protein expression from MkEV-loaded pDNA cargo was similarly determined by plate reader fluorescence data and confocal microscopy. In mouse biodistribution studies, DiD-labeled MkEVs were predominantly detected in bone marrow, followed by liver and spleen 16h-post tail vein injection (plate reader analyses: Bone Marrow - 1.1e 4 ± 0.2 SD; Liver - 9.6e 3 ± 1.0 SD; Spleen - 1.8e 4 ± 0.2 SD. MFI/g tissue; n=3mice/group). Flow cytometry analyses show MkEVs preferentially targeted the hematopoietic compartment (of the MkEV+ cells, 94 ± 1% CD45+ vs 6 ± 1% CD45-, respectively), specifically, the HSPCs (68%, LSK) and LT-HSCs (100%) 48h post intravenous delivery via tail vein injection. Pharmacokinetic studies show that while MkEVs can circulate through highly vascularized tissues like the liver and spleen, they accumulate in the bone marrow. Strikingly, miRFP encoded by the pDNA was exclusively detected in bone marrow (p<0.0001 vs. all other tissues; Fig. 1). In NHPs, dye-labeled MkEVSs were loaded with a MkEV-driven eGFP reporter plasmid. Studies showed preferential biodistribution to bone marrow, and preferential qPCR amplification of the pDNA cargo in bone marrow (both MFI/ ACTB and GFP/ ACTB were significantly higher vs. all other tissues: range p<0.05 through p<0.0001), Fig. 2. A tolerability and repeat dosing study was performed in NHPs. Monkeys were injected with 4 weekly doses of STRM.BIO MkEVs and serial bloodwork was obtained 6h post dose for cytokine evaluation and 5 days post dose for end organ damage assessment (n=4). The study showed no evidence of kidney, hematologic, or liver damage as evidenced by normal creatinine and electrolytes, no significant changes in complete blood counts, coagulation parameters, or liver function tests. There was no evidence of significant cytokine release or inflammatory changes on tissue histology. These data confirm that MkEVs are non-toxic and the platform is amenable to repeat dosing. Taken together, these data establish an advanced gene therapy platform that can target bone marrow specifically following in vivo administration in both mice and NHPs, potentially eliminating the need for current ex vivo approaches to treat rare blood disorders, and providing the critical ability to repeat dose as required in clinic. STRM.BIO is leveraging our platform to develop gene therapies for rare blood diseases in people.

Nanotechnology-Based Drug Delivery Systems for Honokiol: Enhancing Therapeutic Potential and Overcoming Limitations.

Honokiol (HNK) is a small-molecule polyphenol that has garnered considerable attention due to its diverse pharmacological properties, including antitumor, anti-inflammatory, anti-bacterial, and anti-obesity effects. However, its clinical application is restricted by challenges such as low solubility, poor bioavailability, and rapid metabolism. To overcome these limitations, researchers have developed a variety of nano-formulations for HNK delivery. These nano-formulations offer advantages such as enhanced solubility, improved bioavailability, extended circulation time, and targeted drug delivery. However, existing reviews of HNK primarily focus on its clinical and pharmacological features, leaving a gap in the comprehensive evaluation of HNK delivery systems based on nanotechnology. This paper aims to bridge this gap by comprehensively reviewing different types of nanomaterials used for HNK delivery over the past 15 years. These materials encompass vesicle delivery systems, nanoparticles, polymer micelles, nanogels, and various other nanocarriers. The paper details various HNK nano-delivery strategies and summarizes their latest applications, development prospects, and future challenges. To compile this review, we conducted an extensive search using keywords such as "honokiol", "nanotechnology", and "drug delivery system" on reputable databases, including PubMed, Scopus, and Web of Science, covering the period from 2008 to 2023. Through this search, we identified and selected approximately 90 articles that met our specific criteria.

Delivery of Growth Factors to Enhance Bone Repair.

The management of critical-sized bone defects caused by nonunion, trauma, infection, malignancy, pseudoarthrosis, and osteolysis poses complex reconstruction challenges for orthopedic surgeons. Current treatment modalities, including autograft, allograft, and distraction osteogenesis, are insufficient for the diverse range of pathology encountered in clinical practice, with significant complications associated with each. Therefore, there is significant interest in the development of delivery vehicles for growth factors to aid in bone repair in these settings. This article reviews innovative strategies for the management of critical-sized bone loss, including novel scaffolds designed for controlled release of rhBMP, bioengineered extracellular vesicles for delivery of intracellular signaling molecules, and advances in regional gene therapy for sustained signaling strategies. Improvement in the delivery of growth factors to areas of significant bone loss has the potential to revolutionize current treatment for this complex clinical challenge.

Kiwi-derived extracellular vesicles for oral delivery of sorafenib

Sorafenib is an oral treatment for hepatocellular carcinoma (HCC). However, poor water solubility, harsh gastrointestinal environment and off-target effects contribute to the low bioavailability of oral sorafenib. Plant-derived extracellular vesicles (PDEVs) are biological nanovesicles with various bioactive functions that offer significant advantages in the field of oral drug delivery: protection from degradation by gastrointestinal fluids; crossing the intestinal epithelial barrier; specific targeting; safety; and abundant yield. However, there are fewer studies applying PDEVs for anti-tumor drug delivery to extra-digestive tissues. In this study, kiwifruit-derived extracellular vesicles (KEVs) were isolated and purified from kiwifruit, and their natural hepatic accumulation properties were exploited for targeted delivery of sorafenib (KEVs-SFB). Evidence showed that encapsulation of KEVs reduced the leakage of sorafenib in the gastrointestinal environment and enhanced the ability to cross the intestinal epithelium; KEVs-SFB was able to achieve liver accumulation and was predominantly taken up by HepG2 cells; KEVs-SFB was effective in inhibiting 4T1 cell proliferation; in the orthotopic liver cancer model, oral administration of KEVs-SFB inhibited tumor growth and improved the side effects of SFB. This PDEVs-based oral drug delivery platform is important for improving oral bioavailability and reducing drug side effects.

Intracoronary delivery of extracellular vesicles from human cardiac progenitor cells reduces infarct size in porcine acute myocardial infarction.

Intracoronary delivery of extracellular vesicles from human cardiac progenitor cells reduces infarct size in porcine acute myocardial infarction.

In vivo self-assembly and delivery of VEGFR2 siRNA-encapsulated small extracellular vesicles for lung metastatic osteosarcoma therapy

The prognosis of lung metastatic osteosarcoma (OS) remains disappointing. siRNA-based gene silencing of VEGFR2 is a promising treatment strategy for lung metastatic OS, but there is a lack of safe and efficient delivery systems to encapsulate siRNAs for in vivo administration. This study presented a synthetic biological strategy that remolds the host liver with synthesized genetic circuits for efficient in vivo VEGFR2 siRNA delivery. After being taken-up by hepatocytes, the genetic circuit (in the form of a DNA plasmid) reprogrammed the liver to drive the autonomous intrahepatic assembly and encapsulation of VEGFR2 siRNAs into secretory small extracellular vesicles (sEVs), thus allowing for the transport of self-assembled VEGFR2 siRNAs towards the lung. The results showed that our strategy was superior to the positive medicine (Apatinib) for OS lung metastasis in terms of therapeutic efficacy and toxic adverse effects and may provide a feasible and viable therapeutic solution for lung metastatic OS.

Sequence-directed concentration of G protein-coupled receptors in COPII vesicles

G protein-coupled receptors (GPCRs) constitute the largest superfamily of plasma membrane signaling proteins. However, virtually nothing is known about their recruitment to COPII vesicles for forward delivery after synthesis in the endoplasmic reticulum (ER). Here, we demonstrate that some GPCRs are highly concentrated at ER exit sites (ERES) before COPII budding. Angiotensin II type 2 receptor (AT2R) and CXCR4 concentration are directed by a di-acidic motif and a 9-residue domain, respectively, and these motifs also control receptor ER-Golgi traffic. We further show that AT2R interacts with Sar1 GTPase and that distinct GPCRs have different ER-Golgi transport rates via COPII which is independent of their concentration at ERES. Collectively, these data demonstrate that GPCRs can be actively captured by COPII via specific motifs and direct interaction with COPII components that in turn affects their export dynamics, and provide important insights into COPII targeting and forward trafficking of nascent GPCRs.