Rationale: Myocardial injury triggers intense oxidative stress, inflammatory response, and cytokine release, which are essential for myocardial repair and remodeling. Excess reactive oxygen species (ROS) scavenging and inflammation elimination have long been considered to reverse myocardial injuries. However, the efficacy of traditional treatments (antioxidant, anti-inflammatory drugs and natural enzymes) is still poor due to their intrinsic defects such as unfavorable pharmacokinetics and bioavailability, low biological stability, and potential side effects. Nanozyme represents a candidate to effectively modulate redox homeostasis for the treatment of ROS related inflammation diseases. Methods: We develop an integrated bimetallic nanozyme derived from metal-organic framework (MOF) to eliminate ROS and alleviate inflammation. The bimetallic nanozyme (Cu-TCPP-Mn) is synthesized by embedding manganese and copper into the porphyrin followed by sonication, which could mimic the cascade activities of superoxide dismutase (SOD) and catalase (CAT) to transform oxygen radicals to hydrogen peroxide, followed by the catalysis of hydrogen peroxide into oxygen and water. Enzyme kinetic analysis and oxygen-production velocities analysis were performed to evaluate the enzymatic activities of Cu-TCPP-Mn. We also established myocardial infarction (MI) and myocardial ischemia-reperfusion (I/R) injury animal models to verify the ROS scavenging and anti-inflammation effect of Cu-TCPP-Mn. Results: As demonstrated by kinetic analysis and oxygen-production velocities analysis, Cu-TCPP-Mn nanozyme possesses good performance in both SOD-and CAT-like activities to achieve synergistic ROS scavenging effect and provide protection for myocardial injury. In both MI and I/R injury animal models, this bimetallic nanozyme represents a promising and reliable technology to protect the heart tissue from oxidative stress and inflammation-induced injury, and enables the myocardial function to recover from otherwise severe damage. Conclusions: This research provides a facile and applicable method to develop a bimetallic MOF nanozyme, which represents a promising alternative to the treatment of myocardial injuries.

Pyroptosis, characterized by inflammasome activation, membrane Gasdermin D (GSDMD)-pore formulation, and the rapid release of inflammatory cytokines, can induce plaque instability and atherosclerosis progression. Nevertheless, insights into the precise antiatherosclerosis therapies targeting pyroptosis remain limited. Here, a novel biomedical application of natural polyphenol melanin as a theranostic antipyroptosis defense nanoplatform for atherosclerosis is reported. Ultrasmall melanin nanoparticles are easily fabricated and functionalized with cyclo-Arg-Gly-Asp-d-Tyr-Lys conjugated polyethylene glycol to yield cRGD-PEG-MNPs (RpMPs) to target plaque neovascularization, which is confirmed by fluorescence imaging. Importantly, RpMPs act like cell patches to suppress pyroptosis in lipopolysaccharidestimulated macrophages by scavenging reactive oxygen species, downregulating the expression levels of pyroptosis-related proteins (NLRP3, Caspase 1, and GSDMD) and reducing the leakage of inflammatory cytokines (interleukin-1β, interleukin-6, and tumor necrosis factor-α). In vivo studies further reveal that RpMPs can ameliorate the development and improve the stability of atherosclerotic plaques via attenuating NLRP3-stimulated pyroptosis and inducing an anti-inflammatory phenotype in the aorta of ApoE −/− mice. Moreover, chelator-free Gd 3+ -RpMPs exhibit persistent T 1 -weighted contrast-enhanced efficiency and plaque resident on a 9.4 T Micro magnetic resonance scanner in murine atherosclerosis model. Overall, this study suggests the potential for using melanin to develop natural multifunctional nanoplatforms for molecular theranostic in atherosclerosis and other pyroptosis-related diseases.

Cancer immunotherapy, such as the Toll-like receptor (TLR) agonist including CpG oligodeoxynucleotide, has shown potency in clinical settings. However, it is still confronted with multiple challenges, which include the limited efficacy and severe adverse events caused by the rapid clearance and systemic diffusion of CpG. Here we report an improved CpG-based immunotherapy approach composed of a synthetic extracellular matrix (ECM)-anchored DNA/peptide hybrid nanoagonist (EaCpG) via (1) a tailor designed DNA template that encodes tetramer CpG and additional short DNA moieties, (2) generation of elongated multimeric CpG through rolling circle amplification (RCA), (3) self-assembly of densely packaged CpG particles composed of tandem CpG building blocks and magnesium pyrophosphate, and (4) incorporation of multiple copies of ECM binding peptide through hybridization to short DNA moieties. The structurally well-defined EaCpG shows dramatically increased intratumoral retention and marginal systemic dissemination through peritumoral administration, leading to potent antitumor immune response and subsequent tumor elimination, with minimal treatment-related toxicity. Combined with conventional standard-of-care therapies, peritumor administration of EaCpG generates systemic immune responses that lead to a curative abscopal effect on distant untreated tumors in multiple cancer models, which is superior to the unmodified CpG. Taken together, EaCpG provides a facile and generalizable strategy to simultaneously potentiate the potency and safety of CpG for combinational cancer immunotherapies.

Natural Cell Patches In article number 2212748, Longjiang Zhang and co‐workers report a multifunctional nanoplatform cRGD‐PEG‐MNP (RpMP). RpMPs act like cell patches to suppress macrophage pyroptosis, thus potently ameliorating the development of atherosclerosis via targeting plaque neovascularization. Chelator‐free Gd3+‐RpMPs exhibit persistent T1‐weighted contrast‐enhanced efficiency and plaque resident on a 9.4 T Micro MR scanner. The presented nanoplatform possesses the potential for molecular theranostic in pyroptosis‐related diseases.