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Highlights MnO2@Ce6 nanoprobes-loaded-iPS cells (iPS-MnO2@Ce6) were developed for enhanced photodynamic and immunotherapy against cancer. Under the guidance of multi-mode real-time imaging, iPS-MnO2@Ce6 achieved an enhanced photodynamic therapeutic effect and stimulated a strong anti-tumor immune response in the tumor-bearing mouse. Abstract How to trigger strong anti-tumor immune responses has become a focus for tumor therapy. Here, we report the human-induced pluripotent stem cells (iPSs) to deliver MnO2@Ce6 nanoprobes into tumors for simultaneous photodynamic therapy (PDT) and enhanced immunotherapy. Ce6 photosensitizer was attached on manganese dioxide (MnO2) nanoparticles, and resultant MnO2@Ce6 nanoprobes were delivered into mitomycin-treated iPSs to form iPS-MnO2@Ce6 nanoprobes. The iPS-MnO2@Ce6 actively targeted in vivo tumors, the acidic microenvironment triggered interaction between MnO2 and H2O2, released large quantities of oxygen, alleviated hypoxia in tumor. Upon PDT, singlet oxygen formed, broken iPSs released tumor-shared antigens, which evoked an intensive innate and adaptive immune response against the tumor, improving dendritic cells matured, effector T cells, and natural killer cells were activated. Meanwhile, regulatory T cells were reduced, and then the immune response induced by iPS-MnO2@Ce6 was markedly stronger than the immune reaction induced by MnO2@Ce6 (P

Despite its undoubted potential, recent studies have began to highlight the complex processes of photothermal therapy. In this perspective, we tackle several issues that affect current research on photothermal therapy, such as the influence of other factors produced in the process, for instance reactive oxygen species or vapor nanobubbles. After focusing on several of the aspects of photothermal therapy that need further clarification, we step back and see this therapy from a wider angle in order to identify its weaknesses. Finally, we briefly summarize what we consider should be the orientation and key focus of future researches in order to establish the full potential of this rapidly advancing and promising therapy.

How to enhance the therapeutic efficacy of human cytokine induced killers cell (CIK) has become a great challenge. Herein, we report for the first time that human CIK cells loaded with gold nanoprisms were successfully used for targeted photoacoustic imaging, enhanced immunotherapy and photothermal therapy of gastric cancer in vivo. Gold nanoprisms were synthesized and modified with PEG; human CIK cells were prepared and incubated with PEGylated gold nanoprisms (Au GNPrs), and then the effects of human CIK cells labeled with Au NPrs on gastric cancer MGC 803 cells were evaluated and further used for targeted photoacoustic imaging, immunotherapy and photothermal therapy of gastric cancer in vivo in mice models. Results showed that PEGylated Au NPrs could be uptaken high-efficiently by human CIK cells, resultant human CIK cells labeled with AuNPrs could inhibit the growth of gastric cancer MGC 803 cells actively by induced apoptosis and G1 phase arrest, and actively target and accumulate the tumor sites in gastric cancer-bearing nude mice. Enhanced synergistic therapeutic efficacy was demonstrated with the maximal inhibition of tumor through a combination of CIK cells-based immunotherapy for three days and then a continuous gold nanoprisms-based photothermal therapy. In conclusion, human CIK cells labeled with PEGylated Au NPrs can target gastric cancer cells in vivo, enhance immunotherapy and photothermal therapy efficacy, and have a great potential in applications such as targeted imaging, immunotherapy and photothermal therapy of gastric cancer in the near future.

Silver nanoparticles have particular properties that contribute to their very promising applications, novel in various fields of science, such as the development of biosensors, the diagnosis and treatment of cancer, the controlled release of drugs and the antimicrobial potential. The biological synthesis of nanoparticles is of great interest over other physical and chemical methods because the use of toxic chemicals and drastic reaction conditions are avoided. The extracellular biosynthesis using fungi could also make downstream processing much easier than the intracellular biosynthesis. One of the main applications of silver nanoparticles is their antimicrobial activity. Several studies have demonstrated the bactericidal properties of silver nanoparticles are different from silver ions, and that they are strongly influenced by their shape, size, concentration and colloidal state. In the present work, the ability of fungal strains from Uruguay to synthesize silver nanoparticles was studied. Eight fungi were able to synthesize nanoparticles. An extensive physicochemical characterization of the nanoparticles was carried out including ultraviolet-visible spectroscopy, transmission electron microscopy, dynamic light scattering, zeta-potential and gel electrophoretic mobility. According to the characterization and colloidal stability results, nanoparticles from three fungi were selected for antimicrobial activity assays. All nanoparticles were able to inhibit Escherichia coli growth, demonstrating their potential as effective antibacterial agent for use in biomedical applications.

Hybrid and composite nanoparticles represent an attractive material for enzyme integration due to possible synergic advantages of the structural builders in the properties of the nanobiocatalyst. In this study, we report the synthesis of a new stable hybrid nanobiocatalyst formed by biomimetic silica (Si) nanoparticles entrapping both Horseradish Peroxidase (HRP) (EC 1.11.1.7) and magnetic nanoparticles (MNPs). We have demonstrated that tailoring of the synthetic reagents and post immobilization treatments greatly impacted physical and biocatalytic properties such as an unprecedented ~280 times increase in the half-life time in thermal stability experiments. The optimized nanohybrid biocatalyst that showed superparamagnetic behaviour, was effective in the batch conversion of indole-3-acetic acid, a prodrug used in Direct Enzyme Prodrug Therapy (DEPT). Our system, that was not cytotoxic per se, showed enhanced cytotoxic activity in the presence of the prodrug towards HCT-116, a colorectal cancer cell line. The strategy developed proved to be effective in obtaining a stabilized nanobiocatalyst combining three different organic/inorganic materials with potential in DEPT and other biotechnological applications.