Extracellular Vesicle Loaded with Clarithromycin for the Treatment of Infection.

PURPOSE

extracellular vesicles (KPEVs) have been reported as promising nanovesicles for drug delivery. This study aimed to load clarithromycin (CLA) into KPEVs (KPEVS-CLA) and determine the physical properties, drug-releasing efficiency, gastric cell uptake, anti- activities, and anti-inflammatory responses in comparison with free CLA and KPEVs.

METHODS

The size and surface charge of KPEVs-CLA were evaluated using dynamic light scattering and visualized using a transmission electron microscope. The encapsulation efficiency (EE%), loading capacity (LC%), and drug release of KPEVs-CLA were examined using HPLC. Anti- growth and anti-adhesion were evaluated. gene expression, NF-κB signaling proteins, and anti-inflammatory profiles were examined using qRT-PCR, Western blotting, and Bio-Plex immunoassay, respectively. Anti-chemotaxis was then examined using a Transwell assay.

RESULTS

KPEVs-CLA were intact and showed a negative surface charge similar to that of KPEVs. However, slightly enlarged KPEVs were observed. CLA was successfully loaded into KPEVs with EE of 93.45% ± 2.43%, LC of 9.3% ± 3.02%. CLA release in the PBS and gastric mimic buffer with Fickian diffusion ( ≤ 0.43) according to Korsmeyer-Peppas kinetic model (R=0.98). KPEVs-CLA was localized in the gastric cells' cytoplasm and perinuclear region. Anti- growth and anti- adhesion of KPEVs-CLA were compared with those of free CLA with no cytotoxicity to adenocarcinoma gastric cells. KPEVs-CLA significantly reduced IL-8, G-CSF, MIP-1α, and MIP-1β levels. Moreover, KPEVs-CLA showed a superior effect over CLA in reducing G-CSF, MIP-1α, and NF-κB phosphorylation and monocyte chemotactic activities.

CONCLUSION

KPEVs serve as potential carriers of CLA. They exhibited a higher efficiency in inhibiting gastric cell inflammation mediated by infection than free CLA. The establishment of KPEVs-CLA as a nanodrug delivery model for treatment could be applied to other plant extracellular vesicles or loaded with other cancer drugs for gastric cancer treatment.