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Pathogen-mimicking nanoparticles have emerged at the forefront of vaccine delivery technology, offering potent immune activation and excellent biocompatibility. Among these innovative carriers, mannan, a critical component of yeast cell walls, shows promise as an exemplary vaccine carrier. Nevertheless, it faces challenges like unpredictable immunogenicity, rapid elimination, and limited antigen loading due to high water solubility. Herein, mannan with varying carbon chain ratios is innovatively modified, yielding a series of dodecyl chains modified mannan (Mann-C 12 ). Through meticulous screening, a mannan variant with a 40% grafting ratio is pinpointed as the optimal vaccine carrier. Further RNA sequencing confirms that Mann-C 12 exhibits desired immunostimulatory characteristics. Coupled with antigen peptides, Mann-C 12 /OVA 257-280 nanovaccine initiates the maturation of antigen-presenting cells by activating the TLR4 and Dectin-2 pathways, significantly boosting antigen utilization and sparking antigen-specific immune responses. In vivo, experiments utilizing the B16-OVA tumor model underscore the exceptional preventive capabilities of Mann-C 12 /OVA 257-280 . Notably, when combined with immune checkpoint blockade therapy, it displays a profound synergistic effect, leading to marked inhibition of tumor growth. Thus, the work has yielded a pathogen-like nanovaccine that is both simple to prepare and highly effective, underscoring the vast potential of mannan-modified nanovaccines in the realm of cancer immunotherapy., (© 2024 Wiley‐VCH GmbH.)

Constructing a unique electrochemical interface to enhance the catalytic capacity of Pt-based catalysts is indispensable for wider application of the hydrogen evolution reaction (HER). Herein, platinum-analogous molybdenum carbide (Mo 2 C) was combined with a lower content of Pt to construct the Pt/Mo 2 C (C) heterostructure via a solid-phase method, using ammonium molybdate as the precursor. Vulcan-C served as a support to promote the distribution of the Pt and Mo 2 C heterostructure, and cooperative effects between Pt and the Mo 2 C heterostructure contributed to the significantly improved catalytic capacity of Pt. The obtained Pt/Mo 2 C (C) exhibits superior HER activity and enhanced long-term durability in the acidic medium, with a low overpotential of 38 mV at 10 mA cm -2 and a low Tafel slope of 24 mV dec -1 . In particular, a drastically enhanced amount of H 2 production can be achieved (6837.28 mmol h -1 g -1 ). This facile approach not only provides a new pathway for constructing novel heterostructures but also gives an insight into the design of cost-effective Pt-based materials for an efficient HER.

Transcatheter arterial embolization (TAE) is an extensively applied treatment method for hepatocellular carcinoma (HCC). However, the worsened tumor microenvironment (TME, e.g., reduced pH post-TAE) may result in unsatisfactory therapeutic outcome. Herein, a new kind of embolic agent, calcium carbonate encapsulated alginate microspheres (CaCO 3 -ALG MSs) are synthesized. Such CaCO 3 -ALG MSs are able to neutralize the tumor pH owing to the reaction of CaCO 3 with protons, which would not affect the overall morphology of microspheres after decomposition of CaCO 3 . TAE treatment with CaCO 3 -ALG MSs is then conducted in an orthotopic rat liver cancer model. 18 F-Fluorodeoxyglucose micropositron emission tomography/computed tomography imaging is conducted post-TAE and discovered that intra-arterial injection of CaCO 3 -ALG MSs shows obvious enhanced therapeutic outcome compared to the same treatment with bare ALG MSs or the clinically used lipiodol. Further studies including analysis of immune cells in tumors, cytokine assays, and bioinformatics analysis all verify the reverse of immunosuppressive TME toward a more immunosupportive one after TAE with CaCO 3 -ALG MSs. The research not only presents a new CaCO 3 -containing embolic agent for enhanced TAE treatment of HCC but also highlights a clinically meaningful approach to improve cancer treatment via tumor pH neutralization., (© 2021 Wiley-VCH GmbH.)