morphological and mechanical characterization of exosome loaded microneedle patches

Mikronadelpflaster für die nachhaltige Verabreichung von Exosomen in biomedizinischen Anwendungen

Exosomes, which are small vesicles released by cells into the extracellular matrix, have been proposed as potential biotherapeutics and drug delivery vectors for the treatment of several diseases and cancers1. During their biogenesis process, exosomes encapsulate various biologically active molecules from within the cells, including functional proteins and nucleic acids2. As a result, when taken up by recipient cells during the transport process, exosomes have the ability to modulate gene expression and cellular functions in the target cells3. As a kind of natural information messenger, exosomes have been fully taken advantage of in tissue regeneration, immune regulation, and as a delivery carrier4. Through engineering techniques, specific ligands can be enriched on the surface of exosomes, enabling the induction or inhibition of signaling events in recipient cells or targeting specific cell types5. Chemotherapeutic agents can also be loaded into exosomes for cancer treatment6. Moreover, exosomes have the ability to cross the blood-brain barrier for therapeutic cargo delivery, making them highly promising for the treatment of brain disorders7. Compared to liposomes, exosomes exhibit enhanced cellular uptake and improved biocompatibility8. They are capable of efficiently entering other cells while demonstrating better tolerance and lower toxicity9. However, the traditional bolus injection of exosomes is prone to sequestration and rapid clearance by the liver, kidneys, and spleen in the bloodstream10. Moreover, exosomes have poor stability in vitro and are susceptible to storage conditions, which restrict their clinical applications11.
Microneedles, an array of micrometric-sized needle tips, have the capability to penetrate physiological barriers for the delivery of small molecule drugs12, proteins13, nucleic acids14, and nanomedicines15. Microneedles are precisely engineered to target lesions on the skin surface, and their dispersed tips ensure uniform drug distribution at the targeted site, thus amplifying their therapeutic impact16. The design and material composition of microneedles facilitate&#160;the dry storage of bioactive substances such as proteins and nucleic acids, enhancing their stability17. Traditional injection methods have a relatively short duration of action and can cause pain, inducing fear in patients18. The micrometer-sized length of microneedle minimizes tissue trauma and prevents nerve stimulation, thereby eliminating pain and improving patient compliance19. Additionally, the user-friendly nature of microneedles allows patients to self-administer the treatment without the need for specialized personnel16. In addition to the skin, microneedles can also be used in tissues such as the eyes20, oral mucosa21, heart22, and blood vessels23. The application of microneedles for the clinical delivery of exosomes provides a promising and prospective strategy.
Hence, we introduce an exosome-loaded microneedle (exo@MN) patch and disclose its fabrication method. The microneedle patches were fabricated using a two-step casting method, along with centrifugation and vacuum drying, which promotes the aggregation of exosomes at the microneedle tips, thereby enhancing delivery efficiency. Both the needle tips and backing were constructed using materials that exhibit excellent biocompatibility and water solubility. Trehalose and hyaluronic acid (HA) were incorporated as tip materials to provide protection for the exosomes, and polyvinylpyrrolidone (PVP) dissolved in absolute ethanol was chosen as the backing material. The morphology of the microneedle patch was characterized using microscopy and scanning electron microscope&#160;(SEM). The mechanical testing of the microneedle was assessed using a tensile meter to confirm their capability to penetrate the skin, and the release rate on pig skin was investigated to be 60 s. Furthermore, the morphology, size, and protein content of both fresh exosomes and exosomes in exo@MN were characterized using transmission electron microscope&#160;(TEM), nanoparticle tracking analysis (NTA), and western blotting (WB). The internalization of exosomes by dendritic cells (DCs) was characterized using confocal laser scanning microscope&#160;(CLSM), and the maturation of DCs was evaluated through flow cytometry. The morphological characterization and biological functions of the two types of exosomes are essentially consistent.

Autor im Rampenlicht: Innovative Mikronadel-basierte Strategien für verbesserte Exosomenabgabe und Stabilität

Herstellung und Charakterisierung von Mikronadelpflastern für das Laden und Verabreichen von Exosomen

Morphologische und mechanische Charakterisierung von Exosomen-beladenen Mikronadel-Patches

morphological-mechanical-characterization-exosome-loaded-microneedle

Research

JoVE Journal

Bioengineering

Morphological and Mechanical Characterization of Exosome Loaded Microneedle Patches

75 Aufrufe. Bereiten Sie zunächst das mit Exosomen beladene Mikronadelpflaster vor und kleben Sie seine Rückseite auf eine um 45 Grad geneigte Oberfläche. Positionieren Sie das Patch unter einem Stereomikroskop. Schalten Sie die Beleuchtung ein und erfassen Sie die Morphologie des Patches mit einem vierfachen Objektiv.Schneiden Sie für die mechanische Prüfung ein Drei-mal-Drei-Array aus dem Pflaster aus und legen Sie es mit den Spitzen nach oben auf die starr...

Serie: Morphologische und mechanische Charakterisierung von Exosomen-beladenen Mikronadel-Patches

Fabrication and Characterization of Microneedle Patches for Loading and Delivery of Exosomes

Exosomes, as emerging &#34;next-generation&#34; biotherapeutics and drug delivery vectors, hold immense potential in diverse biomedical fields, ranging from drug delivery and regenerative medicine to disease diagnosis and tumor immunotherapy. However, the rapid clearance by traditional bolus injection and poor stability of exosomes restrict their clinical application. Microneedles serve as a solution that prolongs the residence time of exosomes at the administration site, thereby maintaining the drug concentration and facilitating sustained therapeutic effects. In addition, microneedles also possess the ability to maintain the stability of bioactive substances. Therefore, we introduce a microneedle patch for loading and delivering exosomes and share the methods, including isolation of exosomes, fabrication, and characterization of exosome-loaded microneedle patches. The microneedle patches were fabricated using trehalose and hyaluronic acid as the tip materials and polyvinylpyrrolidone as the backing material through a two-step casting method. The microneedles demonstrated robust mechanical strength, with tips able to withstand 2 N. Pig skin was used to simulate human skin, and the tips of microneedles completely melted within 60 s after skin puncture. The exosomes released from the microneedles exhibited morphology, particle size, marker proteins, and biological functions comparable to those of fresh exosomes, enabling dendritic cells uptake and promoting their maturation.

Exosomes possess significant clinical potential, but their practical application is limited due to easy in vivo clearance and poor stability. Microneedles present a solution by enabling localized delivery by puncturing physiological barriers and dry-state preservation, thereby addressing the limitations of exosome administration and expanding their clinical utility.

Exosomes, as emerging &#34;next-generation&#34; biotherapeutics and drug delivery vectors, hold immense potential in diverse biomedical fields, ranging ...