Extracellular vesicles (EVs) such as ectosomes and exosomes have gained attention as promising natural carriers for drug delivery. Exosomes, which range from 30 to 100 nm in diameter, possess a lipid bilayer and are secreted by various cells. Due to their high biocompatibility, stability, and low immunogenicity, exosomes are favored as cargo carriers. The lipid bilayer membrane of exosomes also offers protection against cargo degradation, making them a desirable candidate for drug delivery. However, loading cargo into exosomes remains to be a challenge. Despite various strategies such as incubation, electroporation, sonication, extrusion, freeze–thaw cycling, and transfection that have been developed to facilitate cargo loading, inadequate efficiency still persists. This review offers an overview of current cargo delivery strategies using exosomes and summarizes recent approaches for loading small-molecule, nucleic acid, and protein drugs into exosomes. With insights from these studies, we provide ideas for more efficient and effective delivery of drug molecules by using exosomes.

The antibacterial activity and the synergistic effect with β-lactam antibiotics of a new 1-methylquinolinium iodide derivative were investigated. The experimental results indicate that the compound possesses a strong antibacterial activity against a panel of bacteria including methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus and NDM-1 Escherichia coli with the MIC values from 0.75 μg/mL to 6 μg/mL. In addition, this compound combined with β-lactam antibiotics shows strong synergistic antimicrobial activities against antibiotic-resistant strains of S. aureus. The results of biochemical studies also reveal that this compound can effectively disrupt GTPase activity, polymerization of FtsZ, and cell division to cause cell death. The compound shows high potential for further development as a new generation of antibacterial agents to fight against the emergence of multidrug-resistant bacteria.

Extracellular vesicles (EVs) have recently emerged as a promising delivery platform for CRISPR/Cas9 ribonucleoproteins (RNPs), owing to their ability to minimize off-target effects and immune responses. However, enhancements are required to boost the efficiency and safety of Cas9 RNP enrichment within EVs. In response, we employed the Fc/Spa interaction system, in which the human Fc domain was fused to the intracellular domain of PTGFRN-Δ687 and anchored to the EV membrane. Simultaneously, the B domain of the Spa protein was fused to the C domain of cargos such as Cre or spCas9. Due to the robust interaction between Fc and Spa, this method enriched nearly twice the amount of cargo within the EVs. EVs loaded with spCas9 RNP targeting the HSV1 genome exhibited significant inhibition of viral replication in vitro and in vivo. Moreover, following neuron-targeting peptide RVG modification, the in vivo dosage in neural tissues substantially increased, contributing to the clearance of the HSV1 virus in neural tissues and exhibiting a lower off-target efficiency. These findings establish a robust platform for efficient EV-based SpCas9 delivery, offering potential therapeutic advantages for HSV1 infections and other neurological disorders.

Dengue virus (DENV) annually infects 400 million people worldwide. Unfortunately, there is lack of widely protective vaccine or drugs against DENV. The viral RNA-dependent RNA polymerase (RdRp) of NS5 protein is highly conserved among different DENV subtypes, thus presenting itself as an attractive target for drug design. In the current research, SPRi was performed to screen compounds against DENV2 RdRp and 5(1H)-Quinazolinone,2-(4-bromophenyl)-2,3,4,6,7,8-hexahydro-7,7-dimethyl-1,3-diphenyl (Q63) was successfully screened out with a KD of 0.9 μM. Then, ITC and molecular docking assay was performed to access the binding mechanism between Q63 and DENV2 RdRp. Meanwhile, Q63 also decreased the intermediate dsRNA production, which was the product of RdRp. Further the antiviral effects of Q63 were evaluated on mosquito C6/36 cells and mammalian BHK-21 cells. Q63 reduced CPE and cell toxicity effect after DENV2 infection on C6/36 and BHK-21 cells, with an EC50 of 2.08 μM. Time of addition assay revealed that Q63 affected the early genome RNA replication stage, including genome RNA replication. In addition, Q63 down-regulated STAT1 phosphorylation, ISG15 and ISG54 after DENV2 infection. In summary, Q63 was found to be a novel RdRp non-nucleoside inhibitor and a potential lead compound for coping with DENV infectious disease in the future.