Intestinal organoids can be used as an ex vivo epithelial model to study different drug delivery effects on epithelial cells’ luminal surface. In this study, the impact of surface charge on the delivery of 5-ASA loaded PLGA nanoparticles into the lumen of organoids was investigated. Alginate and chitosan were used to coat the nanoparticles and provide negative and positive charges on the particles, respectively. The organoid growth and viability were not affected by the presence of either alginate- or chitosan-coated nanoparticles. It was shown that nanoparticles could be transported from the serosal side of the organoids to the lumen as the dye gradually accumulated in the lumen by day 2–3 after adding the nanoparticles to the Matrigel. By day 5, the dye was eliminated from the lumen of the organoids. It was concluded that the positively charged nanoparticles were more readily transported across the epithelium into the lumen. It may be attributed to the affinity of epithelial cells to the positive charge. Thus, the organoid can be utilized as an appropriate model to mimic the functions of the intestinal epithelium and can be used as a model to evaluate the benefits of nanoparticle-based drug delivery.
Filarial diseases represent a significant social and economic burden to over 120 million people worldwide and are caused by endoparasites that require the presence of symbiotic bacteria of the genus Wolbachia for fertility and viability of the host parasite. Targeting Wolbachia for elimination is a therapeutic approach that shows promise in the treatment of onchocerciasis and lymphatic filariasis. Here we demonstrate the use of a biodegradable polyanhydride nanoparticle-based platform for the co-delivery of the antibiotic doxycycline with the antiparasitic drug, ivermectin, to reduce microfilarial burden and rapidly kill adult worms. When doxycycline and ivermectin were co-delivered within polyanhydride nanoparticles, effective killing of adult female Brugia malayi filarial worms was achieved with approximately 4,000-fold reduction in the amount of drug used. Additionally the time to death of the macrofilaria was also significantly reduced (five-fold) when the anti-filarial drug cocktail was delivered within polyanhydride nanoparticles. We hypothesize that the mechanism behind this dramatically enhanced killing of the macrofilaria is the ability of the polyanhydride nanoparticles to behave as a Trojan horse and penetrate the cuticle, bypassing excretory pumps of B. malayi, and effectively deliver drug directly to both the worm and Wolbachia at high enough microenvironmental concentrations to cause death. These provocative findings may have significant consequences for the reduction in the amount of drug and the length of treatment required for filarial infections in terms of patient compliance and reduced cost of treatment. Infection with the filarial endoparasites Brugia malayi and its symbiotic bacteria Wolbachia represent a significant burden to both humans and animals. Current treatment protocols include use of multiple drugs over a course of months to years, resulting in high costs, undesirable side effects, and poor patient compliance. By encapsulating two of these drugs, ivermectin and doxycycline, into biodegradable polyanhydride nanoparticles, we report the ability to effectively kill adult B. malayi with up to a 4,000-fold reduction in the amount of drug used. These results demonstrate a promising role for the use of nanoscale drug carriers to reduce both the course of treatment and the amount of drug needed to increase affordability of lymphatic filariasis treatment and enhance patient compliance.
Antisense peptide nucleic acids (PNAs) have yet to translate to the clinic because of poor cellular uptake, limited solubility, and rapid elimination. Cell-penetrating peptides (CPPs) covalently attached to PNAs may facilitate clinical development by improving uptake into cells. We report an efficient technology that utilizes a fully automated fast-flow instrument to manufacture CPP-conjugated PNAs (PPNAs) in a single shot. The machine is rapid, with each amide bond being formed in 10 s. Anti-IVS2-654 PPNA synthesized with this instrument presented threefold activity compared to transfected PNA in a splice-correction assay. We demonstrated the utility of this approach by chemically synthesizing eight anti-SARS-CoV-2 PPNAs in 1 day. A PPNA targeting the 5′ untranslated region of SARS-CoV-2 genomic RNA reduced the viral titer by over 95% in a live virus infection assay (IC50 = 0.8 μM). Our technology can deliver PPNA candidates to further investigate their potential as antiviral agents.