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Epigallocatechin-3-gallate (EGCG), the most abundant tea polyphenol, possesses excellent anti-inflammation properties. Emerging studies proved its potent potential as an immune checkpoint (ICP) inhibitor for anticancer therapy. However, the low bioavailability of EGCG reduces its treatment efficiency. In this work EGCG-based nanomedicine EGCG–ZIF-8@PDA–PEG (EZP) was developed via the coordination between ZIF-8 MOF and EGCG, followed by polydopamine and PEG functionalization for efficient tumor-targeting EGCG delivery. Results demonstrated that the EGCG loading rate in EZP reached up to 85%. Both in vitro and in vivo studies proved that the EZP nanoparticles were capable of inhibiting the expression of ICP molecules and modulating the inflammatory tumor microenvironment, evidenced by the suppression of PD-L1 expression, the reduction of inflammatory cytokines, and the resultant decline in the number of immunosuppressive cells, for instance, myeloid-derived suppressor cells, tumor-associated macrophages, and regulatory T cells. These synergistic effects significantly improved the infiltration of dendritic cells and T cells in tumors, realizing an inspiring antitumor effect. [ABSTRACT FROM AUTHOR]

Engineered nanomaterials (ENMs) to which humans are exposed intentionally as nanomedicines or unintentionally as invaders, may elicit unforeseen immune reactions. An uncontrollable ENM‐induced immune response poses a potential danger to the human body. During an immunological reaction, interleukin (IL)‐1 family cytokines, which play key roles under both physiological and pathological conditions, can be secreted by various types of cells into the surrounding environment to induce a series of defensive reactions. However, the crucial roles played by IL‐1 family cytokines in ENM‐induced immunological responses have not attracted enough attention from researchers to date. In this review, ENM‐mediated inflammatory responses and immunotoxicity are discussed, with the main focus directed to IL‐1 family cytokines, including IL‐1α, IL‐1β, IL‐1Ra, IL‐18, IL‐33, IL‐36, IL‐37, and IL‐38. The potential molecular mechanisms of IL‐1 family cytokine activity triggered by ENMs, particularly the activation of IL‐1α, IL‐1β, IL‐18, and IL‐33, are also reviewed. The understanding of IL‐1 family cytokines on nanoimmunosafety provides a fundamental basis for designing safe ENMs that can potentially be used for nanomedicine. This article is categorized under:Toxicology and Regulatory Issues in Nanomedicine > Toxicology of Nanomaterials [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs) are an increasingly common contaminant in agro-environments, and their potential effect on genetically modified (GM) crops has been largely unexplored. GM crop exposure to NPs is likely to increase as both technologies develop. To better understand the implications of nanoparticles on GM plants in agriculture, we performed a glasshouse study to quantify the uptake of FeO NPs on transgenic and non-transgenic rice plants. We measured nutrient concentrations, biomass, enzyme activity, and the concentration of two phytohormones, abscisic acid (ABA) and indole-3-acetic acid (IAA), and malondialdehyde (MDA). Root phytohormone inhibition was positively correlated with FeO NP concentrations, indicating that FeO had a significant influence on the production of these hormones. The activities of antioxidant enzymes were significantly higher as a factor of low FeO NP treatment concentration and significantly lower at high NP concentrations, but only among transgenic plants. There was also a positive correlation between the treatment concentration of FeO and iron accumulation, and the magnitude of this effect was greatest among non-transgenic plants. The differences in root phytohormone production and antioxidant enzyme activity between transgenic and non-transgenic rice plants in vivo suggests that GM crops may react to NP exposure differently than conventional crops. It is the first study of NPs that may have an impact on GM crops, and a realistic significance for food security and food safety. [ABSTRACT FROM AUTHOR]

MoS2–ZnO composites were synthesized using a solution-based method. The scanning electron microscopy and transmission electron microscopy analysis demonstrated that ZnO nanoparticles with a size of about 4.5 nm were coated on the basal surface of MoS2 nanosheets with an expanded spacing of the (002) plane. The MoS2–ZnO composite-based poly(methyl methacrylate) (PMMA) organic glasses (MoS2–ZnO–PMMA organic glasses) were prepared through a polymerization process. The nonlinear absorption (NLA), nonlinear scattering (NLS), and optical limiting (OL) properties of the MoS2–ZnO–PMMA organic glasses with different amounts of MoS2–ZnO were investigated using a modified Z-scan technique. Compared to MoS2–PMMA and ZnO–PMMA organic glasses, the MoS2–ZnO–PMMA organic glasses exhibited enhanced NLA, NLS, and OL properties, which were attributed to the interfacial charge transfer between MoS2 nanosheets and ZnO nanoparticles, the layered structure of MoS2 nanosheets, the small size effect of ZnO nanoparticles, and the local field effect. In addition, a changeover from saturable absorption (SA) to reverse saturable absorption (RSA) could be realized in the MoS2–ZnO–PMMA organic glasses by adjusting the input energy. The total nonlinear extinction coefficient and response time of the MoS2–ZnO–PMMA organic glasses could be up to 2380 cm GW−1 and several hundred picoseconds, respectively. Compared to the MoS2 films, the MoS2–ZnO–PMMA organic glasses have higher optical damage threshold, better mechanical strength and flexibility. Thus the MoS2–ZnO–PMMA organic glasses are very promising for optical devices such as optical limiters, optical shutters, ultrafast lasers, and ultrafast optical switches. [ABSTRACT FROM AUTHOR]