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Background: Lines of evidence indicated that, immune checkpoints (ICs) inhibitors enhanced T cell immune response to exert anti-tumor effects. However, T cell exhaustion has been so far a major obstacle to antitumor immunotherapy in colorectal cancer patients. Our previous studies showed that ginseng-derived nanoparticles (GDNPs) inhibited the growth of various tumors by reprograming tumor-associated macrophages (TAMs) and downregulated the ICs expression on T cells in tumor microenvironment (TME), but the underlying effector mechanisms remained unclear., Methods: The correlation between arginase-1 (ARG1) and T cells was computed based on the colorectal cancer patients in TCGA database. In vitro, we observed that GDNPs reprogrammed TAMs inhibited ARG1 release and ultimately ameliorated T cell exhaustion according to several techniques including WB, PCR, ELISA and flow cytometry. We also used an in vivo MC38 tumor-bearing model and administered GDNPs to assess their anti-tumor effects through multiple indices. The mechanism that GDNPs improved T cell exhaustion was further clarified using the bioinformatics tools and flow cytometry., Results: GDNPs reprogramed TAMs via reducing ARG1 production. Moreover, normalized arginine metabolism ameliorated T cell exhaustion through mTOR-T-bet axis, resulting in reduced ICs expression and enhanced CD8 + T cells expansion., Conclusions: By regulating the mTOR-T-bet axis, GDNPs reprogramed macrophages to regulate ARG1 release, which further ameliorated T cell exhaustion in TME. These findings provided new insights into comprehending the mechanisms underlying the mitigation of T cell exhaustion, which may facilitate the development of innovative therapeutic strategies in the field of cancer treatment., (© 2023. The Author(s).)

Cold tumor microenvironment (TME) marked with low effector T cell infiltration leads to weak response to immune checkpoint inhibitor (ICI) treatment. Thus, switching cold to hot TME is critical to improve potent ICI therapy. Previously, we reported extracellular vesicle (EV)-like ginseng-derived nanoparticles (GDNPs) that were isolated from Panax ginseng C.A. Mey and can alter M2 polarization to delay the hot tumor B16F10 progression. However, the cold tumor is more common and challenging in the real world. Here, we explored a combinatorial strategy with both GDNPs and PD-1 (programmed cell death protein-1) monoclonal antibody (mAb), which exhibited the ability to alter cold TME and subsequently induce a durable systemic anti-tumor immunity in multiple murine tumor models. GDNPs enhanced PD-1 mAb anti-tumor efficacy in activating tumor-infiltrated T lymphocytes. Our results demonstrated that GDNPs could reprogram tumor-associated macrophages (TAMs) to increase CCL5 and CXCL9 secretion for recruiting CD8 + T cells into the tumor bed, which have the synergism to PD-1 mAb therapy with no detected systemic toxicity. In situ activation of TAMs by GDNPs may broadly serve as a facile platform to modulate the suppressive cold TME and optimize the PD-1 mAb immunotherapy in future clinical application., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2021 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.)

Background: It is unclear whether plant-derived extracellular vesicles (EVs) can mediate interspecies communication with mammalian cells. Tumor-associated macrophages (TAMs) display a continuum of different polarization states between tumoricidal M1 phenotype and tumor-supportive M2 phenotypes, with a lower M1/M2 ratio correlating with tumor growth, angiogenesis and invasion. We investigated whether EVs from ginseng can alter M2-like polarization both in vitro and in vivo to promote cancer immunotherapy., Methods: A novel EVs-liked ginseng-derived nanoparticles (GDNPs) were isolated and characterized from Panax ginseng C. A. Mey. Using GDNPs as an immunopotentiator for altering M2 polarized macrophages, we analyzed associated surface markers, genes and cytokines of macrophages treated with GDNPs. Mice bearing B16F10 melanoma were treated with GDNPs therapy. Tumor growth were assessed, and TAM populations were evaluated by FACS and IF., Results: GDNPs significantly promoted the polarization of M2 to M1 phenotype and produce total reactive oxygen species, resulting in increasing apoptosis of mouse melanoma cells. GDNP-induced M1 polarization was found to depend upon Toll-like receptor (TLR)-4 and myeloid differentiation antigen 88 (MyD88)-mediated signaling. Moreover, ceramide lipids and proteins of GDNPs may play an important role in macrophage polarization via TLR4 activation. We found that GDNPs treatment significantly suppressed melanoma growth in tumor-bearing mice with increased presence of M1 macrophages detected in the tumor tissue., Conclusions: GDNPs can alter M2 polarization both in vitro and in vivo, which contributes to an antitumor response. The polarization of macrophages induced by GDNPs is largely dependent on TLR4 and MyD88 signalling. GDNPs as an immunomodulator participate in mammalian immune response and may represent a new class of nano-drugs in cancer immunotherapy.

Iron oxide nanoparticles (IONPs) are generally used in multiple biomedical applications. The tissue repair effect of IONPs had been demonstrated in the previous studies of our group, but the underlying mechanism is unclarified. It is well known that stem cell-based therapies show promising prospect in tissue engineering and regenerative medicine, however, whether IONPs could modulate stem cell fate to promote tissue repair is still unclear. Herein, we found that IONPs could promote osteogenic differentiation of human bone-derived mesenchymal stem cells (hBMSCs) in vitro. To insightfully understand the molecular mechanisms, we performed systematic analyses by use of gene microarray assay and bioinformatics analysis, which revealed that gene expression was widely regulated and classical mitogen-activated protein kinase (MAPK) signal pathway was activated by IONPs treatment. As a result, downstream genes of this pathway were regulated to promote osteogenic differentiation. In summary, the present study elucidates a molecular basis explaining how IONPs effect on hBMSCs, which could have many meaningful impacts for stem cells application in regenerative medicine., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Abstract Aggregation-induced emission (AIE) should be the most interest fluorescent phenomenon over the past few decades. The luminescence polymeric nanoparticles (LPNs) with AIE characteristic have attracted great research attention for biological imaging and many other biomedical applications owing to their good biocompatibility and negative toxicity. However, the preparation of LPNs with desirable optical properties using traditional organic dyes still remains a great challenge for the aggregation-caused quenching (ACQ) effect and aggregation of hydrophobic dyes in the core of LPNs. In this work, we reported a novel and simple method for fabrication of biodegradable AIE-active LPNs via the combination of condensation and click reactions. For preparation of these AIE-active LPNs, the thiol groups-containing hydrophilic copolymers (PEG-MA) were first synthesized through the condensation reaction between polyethylene glycol and mercaptosuccinic acid. The PEG-MA copolymers were further reacted with AIE dye PhE-OE through a catalyst-free thiol-yne click reaction. These obtained PEG-MA-PhE LPNs were fully characterized by a number of characterization techniques. All the results confirmed that PEG-MA-PhE LPNs possess excellent compatibility, intense red luminescence, great photostability and high water dispersibility. These features make PEG-MA-PhE LPNs promising candidates for various biomedical applications. Graphical abstract A novel catalyst-free thiol-yne click chemistry was developed for the preparation of biodegradable luminescent polymeric nanoparticles with aggregation-induced emission feature. Unlabelled Image Highlights • Catalyst-free thiol-yne click reaction • Aggregation-induced emission luminescent polymeric nanoparticles • The AIE-active LPNs are degradable potential. • The AIE-active LPNs promising for biomedical applications. [ABSTRACT FROM AUTHOR]

Wurtzite Cu 2 ZnSnS 4 (CZTS) nanoparticles with bandgaps of about 1.53 eV were synthesized by a simple solvothermal method with ethanediamine (En) as the reaction solvent. The effect of the annealing conditions on the structural stability and photoelectrical properties of wurtzite structured CZTS nanoparticles was detailedly studied. Raman spectra and X-ray photoelectron spectroscopy studies indicated that wurtzite CZTS would be changed to kesterite CZTS with the increasing of annealing temperature from 500 °C to 600 °C, no matter what annealing condition was adopted. But no secondary phases were found when the annealing atmosphere was N 2 /H 2 S (5%). Some secondary phases, such as CuS, Cu 3 SnS 4 or Cu 4 SnS 4 , were found when CZTS nanoparticles were annealed in N 2 atmosphere or vacuum. Annealing process could enhance the photoelectrical properties of CZTS nanoparticle thin films, especially when they were annealed in N 2 /H 2 S (5%). [ABSTRACT FROM AUTHOR]

A facile and inexpensive method was developed to synthesize high quality and ultra-long Cu 2 CdSnS 4 (CCTS) nanowires. X-ray diffraction (XRD) and Raman spectra studies indicated that wurtzite structured CCTS was formed. The nanowires had diameters of 80–100 nm and lengths of up to several micrometers. The bandgap of CCTS nanowires was about 1.42 eV determined by UV–vis–NIR absorption spectrum. The photoresponses of CCTS nanowire thin films indicated that they were promising for use in photovoltaic applications. [ABSTRACT FROM AUTHOR]

This work investigated the effect of graphene nanoplatelets (GNPs) on the water absorption and impact resistance of fibre-reinforced metal laminates (FMLs) under hygrothermal and salt spray environments. Containing GNPs of 0.1, 0.3, 0.5 and 1.0 wt%, the resulting nanocomposite FMLs were investigated for 28 days of aging in the environments. The salt-spray environment was found to pose a more serious effect on FMLs than the hygrothermal environment. The addition of GNPs at 0.3 wt% effectively reduced the water absorption of FMLs by 57.6% whilst improving their impact resistance by 150.6% in comparison with pure FML in the case of treatment by the salt-spray environment. The water absorption reduction is caused by GNPs creating a tortuous path for diffusion of water molecules and restricting the intermolecular motion of the epoxy molecules. The impact resistance improvement can be attributed to GNPs improving the modulus and crack-resistance of the epoxy matrix and thus the interfacial bonding of FMLs. [ABSTRACT FROM AUTHOR]

Abstract: Quaternary Cu2CdSnS4 nanoparticles, which are useful for the photovoltaic applications, were successfully synthesized by using a simple solvothermal route. Slightly polydispersed nanoparticles were obtained at temperature of 180°C, analyzed by transmission electron microscopy (TEM). The cernyite structured Cu2CdSnS4 nanoparticles were confirmed by X-ray diffraction (XRD). The morphology and the stoichiometric ratio of the nanoparticles were characterized by scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The chemical states of the elements in the nanoparticles were analyzed by high-resolution X-ray photoelectron spectroscopy (XPS). The band gap of the as-synthesized Cu2CdSnS4 nanoparticles was determined by UV–Vis absorption spectra measurement. [Copyright &y& Elsevier]

Image blurring of MeV transmission electrons for gold nanoparticles on the top surface of micrometer-thick specimens has been investigated using the Monte Carlo simulation. Both the simulated line density profile and therefore image blurring were in good agreement with the experimental ones in the ultrahigh voltage electron microscope. Quantitative effects of specimen thickness and electron energy on image blurring were presented, in which the specimen thickness had a greater influence. Image blurring was demonstrated to be caused mainly by multiple elastic scattering, but it could be reduced to several nanometers for a 5 µm thick epoxy-resin specimen at the electron energy of 2 MeV. [ABSTRACT FROM PUBLISHER]

Abstract: CdS nanoparticles sensitized TiO2 nanotube arrays photoanode for semiconductors sensitized solar cells (SSSCs) were prepared by sonication-assisted sequential chemical bath deposition (SSCBD) approach and labeled as S-CdS/TNTAs. The S-CdS/TNTAs solar cell was assembled into a typical sandwich structure with backside illumination. Short-circuit current density (J sc), open circuit potential (V oc), fill factor (FF) and power conversion efficiency (PCE) of the cells under AM 1.5 irradiation were about 4.16mAcm−2, 446mV, 43.9% and 0.814%, respectively. Compared with classical sequential chemical bath deposition (SCBD), SSCBD process could effectively prevent CdS nanoparticles aggregating at the top surface of TNTAs and resulted in an increase of PCE by 65.8%. Increased performance of S-CdS/TNTAs solar cell may be attributed to the more efficient charge-transfer process and the lower charge recombination, as evidenced from FESEM and electrochemical impedance spectroscopy (EIS). [Copyright &y& Elsevier]