In recent years, microbiota-based tumor immunotherapy has become a hotspot in cancer research. However, the use of microorganisms alone to activate the immune response for antitumor therapy was unsatisfactory. In this study, we biosynthesized gold nanoparticles (AuNPs) and platinum nanoparticles (PtNPs) based on yeast microcapsules to activate the immune response for antitumor treatment in synergy with chemodynamic therapy (CDT) and photothermal therapy (PTT). We generated AuNPs and PtNPs on yeast microcapsules (YAP) and fabricated nanoscale particles (Bre-YAP) by ultrasonic fragmentation and differential centrifugation. Bre-YAP retained the glucan component of yeast as an adjuvant; in the meantime, these two kinds of metal nanoparticles contained were excellent CDT and PTT mediators. By inspection, they could reach a high level of distribution in tumors and tumor-draining lymph nodes (TDLNs). Under the laser irradiation of tumors, this immunological nanomaterial significantly remodeled the microenvironments of tumors and TDLNs. The primary tumors were effectively inhibited or even eradicated, and the overall survival of mice was significantly improved as well. Therefore, yeast microcapsule-based Bre-YAP with immune properties could be used as an effective cancer treatment modality.
In order to construct an oral drug delivery system to improve the bioavailability of drugs. This project prepared a compound drug carrier that combines the advantages of biological carriers and synthetic carriers. This oral drug delivery system (YP-MPA-ZnO-DOX) consists of yeast microcapsules (YP) and DOX-loaded ZnO nanoparticles modified with 3-mercaptopropionic acid (MPA). The average particle size of the particles was 4620 nm and the potential was about +22.7 mV as measured by particle size and zeta potential. The in vitro release experiments showed that the DOX release rate of YP-MPA-ZnO-DOX in simulated gastric fluid (SGF) for 11 h was about 20 %. The cumulative release rate of DOX in simulated intestinal fluid (SIF) for 11 h was about 10 %, indicating that YP-MPA-ZnO-DOX could resist gastrointestinal fluid erosion and had drug retention effects. Meanwhile, in the simulated tumor environment, the cumulative release of DOX could reach 97.6 %, almost completely released. Cellular experiments demonstrated that the inhibition rate of YP-MPA-ZnO-DOX on HepG2 and HCT116 cells was close to 75 % after 48 h, which was much higher than that of DOX alone. Pharmacokinetic studies demonstrated that compared with free DOX, the half-life of YP-MPA-ZnO-DOX could be prolonged to 13.621 ± 0.09 h, which significantly improved the bioavailability of DOX after oral administration. Utilization after oral administration of DOX. In conclusion, YP-MPA-ZnO-DOX provides a promising application for oral DOX.
危险品化学品经营许可证（带存储）