M2 Macrophage Hybrid Membrane-Camouflaged Targeted Biomimetic Nanosomes to Reprogram Inflammatory Microenvironment for Enhanced Enzyme-Thermo-Immunotherapy

Exploration of uricase-like activity in Pd@Ir nanosheets and their application in relieving acute gout using self-cascade reaction

Gout, marked by the deposition of sodium urate crystals in joints and peripheral tissues, presents a considerable health challenge. Recent research has shown a growing interest in nanozyme-based treatments for gout. However, literature on nanozymes that combine uricase-like (UOX) activity for uric acid (UA) degradation with catalase (CAT)-like activity for H2O2 elimination through a self-cascade reaction is limited. Herein, we discovered that two-dimensional Pd@Ir nanosheets (NSs) exhibit UOX and CAT activities effectively. Notably, we observed a size-dependent effect of Pd@Ir on activation energy during UA degradation, with the larger Pd@Ir NSs demonstrating a lower energy barrier. The 46-nm Pd@Ir had activation energy as low as 35.9 kJ/mol, surpassing the efficiency of natural bacterial uricase and most reported nanozymes. Through a tandem self-cascade reaction of Pd@Ir, UA was effectively degraded via UOX activity, while the byproduct H2O2 was simultaneously eliminated by CAT-like activity. Cell experiments revealed that Pd@Ir protect normal cells from oxidative stress and promote cell proliferation, demonstrating an excellent self-cascade effect. Additionally, Pd@Ir substantially alleviated gout symptoms in monosodium urate-induced acute gout mice without causing toxic effects on biological organs and tissues. This study opens new avenues for using nanozyme-based cascade reaction systems in the treatment of metabolic diseases.

Bioinspired Adhesive Hydrogel Platform with Photothermal Antimicrobial, Antioxidant, and Angiogenic Properties for Whole-Process Management of Diabetic Wounds

Diabetic wound healing remains a major challenge in modern medicine. The persistent inflammation and immune dysfunction hinder angiogenesis by producing excessive ROS and increasing the susceptibility to bacterial infection. In this study, we developed an integrated strategy for whole-process management of diabetic wounds based on a bioinspired adhesive hydrogel platform with hemostasis, photothermal antimicrobial, antioxidant, anti-inflammatory, and angiogenic properties. A composite hydrogel (termed AQTGF) using poly(acrylic acid) (PAA) and quaternized chitosan (QCS) as the backbone materials and loaded with a TA-Gd/Fe-bimetallic-phenolic coordination polymer was prepared. The AQTGF hydrogel displayed favorable mechanical properties, self-healing capabilities, adhesion characteristics, and photothermal response performance. In vitro experiments demonstrated that the AQTGF hydrogel exhibits excellent photothermal antimicrobial capacity and antioxidant, angiogenic, and M2 macrophage phenotype polarizing properties. In addition, the rat tail amputation and liver hemostasis experiments demonstrated that the AQTGF hydrogel had excellent hemostasis performance. Moreover, in vivo studies have indicated that AQTGF hydrogel can facilitate diabetic wound healing by accelerating epidermal growth, promoting collagen deposition, modulating macrophage M2 polarization, inhibiting inflammation, and promoting angiogenesis. In conclusion, this study provides an adaptable hydrogel that holds promise for the treatment of chronic diabetic wounds.

Macrophage membrane-encapsulated miRNA nanodelivery system for the treatment of hemophilic arthritis

Hemophilic arthritis (HA) is one of the most pathologically altered joint diseases. Specifically, periodic spontaneous hemorrhage-induced hyperinflammation of the synovium and irreversible destruction of the cartilage are the main mechanisms that profoundly affect the behavioral functioning and quality of life of patients. In this study, we isolated and characterized platelet-rich plasma-derived exosomes (PRP-exo). We performed microRNA (miRNA) sequencing and bioinformatics analysis on these exosomes to identify the most abundant miRNA, miR-451a. Following this, we developed an M@ZIF-8@miR nanotherapeutic system that utilizes nanoscale zeolitic imidazolate framework (ZIF) as a carrier for miRNA delivery, encapsulated within M2 membranes to enhance its anti-inflammatory effects. In vitro and in vivo studies demonstrated that M@ZIF-8@miR significantly reduced pro-inflammatory cytokines, controlled synovial inflammation, and achieved potent therapeutic efficacy by reducing joint damage. We suggest that the ability of M@ZIF-8@miR nanocomposites to inhibit pro-inflammatory cytokines, enhance cellular uptake, and exhibit good endosomal escape properties makes them promising carriers for the efficient delivery of therapeutic nucleic acid drugs. This approach delays joint degeneration and provides a promising combinatorial strategy for HA treatment.

Inhibition of macrophage polarization and pyroptosis in collagen-induced arthritis through MSC-exo and ginsenoside Rh2

BACKGROUND

Rheumatoid arthritis (RA) is a chronic autoimmune disease characterized by joint inflammation, tissue damage, and fibrosis, significantly affecting the quality of life. While there are currently some effective treatments available, they often come with side effects. There is an urgent need to find new treatments that can further improve therapeutic outcomes and reduce side effects.

METHODS

Our study investigates the role of Mesenchymal Stem Cell exosomes (MSC-exo) combined with Ginsenoside Rh2 (Rh2) in the treatment of RA. We specifically focus on how this combined strategy influences macrophage polarization and pyroptosis. This research utilized a collagen-induced rat arthritis model.

RESULTS

The study findings reveal that the combination of MSC-exo combined with Rh2 can inhibit the polarization of M1 macrophages, increase the proportion of M2-like macrophages, and suppress M1-like macrophage pyroptosis via the NLRP3/Caspase11/GSDMD-N pathway. In the rat arthritis model, the combination of MSC-exo and Rh2 showed synergistic therapeutic effects.

CONCLUSION

This research contributes to a deeper understanding of RA's pathogenesis and presents new potential targeted therapeutic interventions. The combined application of MSC-exo and Rh2 offers promising insights for future innovative strategies in RA treatment, paving the way for more effective management of this autoimmune disease.

Novel Modifications and Delivery Modes of Cyclic Dinucleotides for STING Activation in Cancer Treatment

The microenvironment tends to be immunosuppressive during tumor growth and proliferation. Immunotherapy has attracted much attention because of its ability to activate tumor-specific immune responses for tumor killing. The cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway is an innate immune pathway that activates antitumor immunity by producing type I interferons. Cyclic dinucleotides (CDNs), produced by cGAS sensing cytoplasmic abnormal DNA, are major intermediate activating molecules in the STING pathway. Nowadays, CDNs and their derivatives have widely worked as powerful STING agonists in tumor immunotherapy. However, their clinical translation is hindered by the negative electrical properties, sensitivity to hydrolytic enzymes, and systemic toxicity. Recently, various CDN delivery systems have made significant progress in addressing these issues, either through monotherapy or in combination with other treatment modalities. This review details recent advances in CDNs-based pharmaceutical development or delivery strategies for enriching CDNs at tumor sites and activating the STING pathway.

A Closed-Loop Cascade Strategy for On-Demand Regulation of Uric Acid

Despite that the current anti-hyperuricemia drugs can effectively reduce uric acid (UA) levels, imprecise medication dosage or uncontrolled lowering of UA levels may result in undesired effects. To address this issue, a closed-loop cascade strategy based on a biocompatible network composite, NW-FPNP/uricase (UOX), is proposed for on-demand regulation of UA levels. NW-FPNP/UOX is constructed by encapsulation of UOX) as UA-responsive element and FPNP, a nanoparticle of phenylboronic acid modified xanthine oxidase (XOD) inhibitor febuxostat, as H2O2-sensitive element with AMP/Gd3+ network. It interrelates the UA metabolization and generation processes into a closed loop of cascade reactions involving UOX-catalyzed UA metabolization and H2O2 generation, H2O2-triggered febuxostat regeneration and XOD inhibition, and XOD-catalyzed UA generation. Through UA level-dependent auto-adjustment of XOD activity, specially 6% at 600 × 10-6 m UA compared to 82% at 100 × 10-6 m, UA levels can be regulated to an appropriate range through dynamically balancing UA metabolization and generation. This biocompatible on-demand UA regulation system prevents the overdose of UA-lowering medications and avoids hypouricemia in hyperuricemia treatment, demonstrating great potential in intelligent UA level management. This work also introduces a new concept of a closed-loop cascade strategy for on-demand regulation of biochemical indicators within specific thresholds.

Tumor-Targeted Catalytic Immunotherapy

Cancer immunotherapy holds significant promise for improving cancer treatment efficacy; however, the low response rate remains a considerable challenge. To overcome this limitation, advanced catalytic materials offer potential in augmenting catalytic immunotherapy by modulating the immunosuppressive tumor microenvironment (TME) through precise biochemical reactions. Achieving optimal targeting precision and therapeutic efficacy necessitates a thorough understanding of the properties and underlying mechanisms of tumor-targeted catalytic materials. This review provides a comprehensive and systematic overview of recent advancements in tumor-targeted catalytic materials and their critical role in enhancing catalytic immunotherapy. It highlights the types of catalytic reactions, the construction strategies of catalytic materials, and their fundamental mechanisms for tumor targeting, including passive, bioactive, stimuli-responsive, and biomimetic targeting approaches. Furthermore, this review outlines various tumor-specific targeting strategies, encompassing tumor tissue, tumor cell, exogenous stimuli-responsive, TME-responsive, and cellular TME targeting strategies. Finally, the discussion addresses the challenges and future perspectives for transitioning catalytic materials into clinical applications, offering insights that pave the way for next-generation cancer therapies and provide substantial benefits to patients in clinical settings.

Uricase-Expressing Engineered Macrophages Alleviate Murine Hyperuricemia

Background: Uricase, or urate oxidase (Uox) is a key enzyme in uric acid (UA) metabolism and has been applied in clinical treatment of human hyperuricemia (HUA). However, the current clinically applied uricases, despite their potent urate-lowering capacity, tend to form anti-drug antibodies because of their immunogenicity, leading to increased risk of anaphylaxis, faster drug clearance and reduced or even complete loss of therapeutic effect, limiting their clinical application. In this study, we constructed engineered macrophages that stably expressed uricase, which might serve as a promising alternative to the direct injection of uricases. Materials and Methods: Engineered macrophages RAW264.7 cells were injected intravenously to treat hyperuricemic KM mice. Serum uric acid and bio-indicators for renal and hepatic functions were detected by an automatic biochemical analyzer; inflammatory cytokines were determined by ELISA; the livers and kidneys of the mice were sectioned for histological examination. Results: The uricase-expressing macrophages reduced UA levels from 300 ± 1.5 μmol/L to 101 ± 8.3 μmol/L in vitro. And in an HUA mouse model established by gavage with yeast extract, intravenous injection of the engineered macrophages could reduce the serum uric acid (sUA) of mice to normal level on the 14th day of modeling, with a decrease of 48.6%, and the urate-lowering effect was comparable to that of the first-line clinical drug allopurinol. In terms of safety, engineered macrophages did not cause liver or kidney dysfunction in mice, nor did they induce systemic immune response. Conclusions: Using macrophages as a chassis to deliver uricase might be a new, safe and effective strategy for the treatment and control of hyperuricemia.

Reactive oxygen species-responsive polydopamine-PtCuTe nanoparticle-loaded microneedle system for promoting the healing of infected skin wounds

Nanozymes, known for their high efficiency in scavenging reactive oxygen species (ROS), have received significant attention in promoting the healing of infected wounds. Herein, we reported a novel multifunctional PDA-PtCuTe nanozyme with excellent ROS scavenging, antibacterial, pro-angiogenic, anti-inflammatory, and immune regulatory properties. It was loaded onto microneedles (PTPP-MN) for treating infected wounds. In vitro experiments demonstrated its ability to scavenge ROS and exhibit antioxidant properties. Compared to PT-MN (11.03 ± 3.37 %) and PTP-MN (42.30 ± 2.60 %), the ROS scavenging rate of PTPP-MN reached 63.63 ± 4.42 %. The microneedle exhibits good biocompatibility, stimulating fibroblast migration, endothelial angiogenesis, and M2 macrophage polarization. Additionally, it effectively eliminates ROS and provides antioxidant effects while inhibiting the viability of S. aureus and E. coli. Animal experiments showed that the PTPP-MN group achieved near-complete re-epithelialization by the third day compared to other groups. Histological observations revealed that the PTPP-MN group exhibited enhanced granulation tissue formation, epithelial regeneration, and angiogenesis. After PTPP-MN treatment, the local immune response shifted from a pro-inflammatory state to a pro-regenerative state. Our results indicate that PTPP-MN holds great promise for infected wound healing with reduced scar formation.

Monitoring the Cascade of Monocyte-Derived Macrophages to Influenza Virus Infection in Human Alveolus Chips

Respiratory viruses ravage the world and seriously threaten people's health. Despite intense research efforts, the immune mechanism underlying respiratory virus-induced acute lung injury (ALI) and pulmonary fibrosis (PF) has not been fully elucidated. Here, the cascade of monocyte-derived macrophages to influenza A virus infection is monitored on an optimized human alveolus chip to reveal the role of macrophages in the development of ALI and PF. We find that viral infection causes damage to the alveolar air-liquid barrier and the release of inflammatory cytokines, which induce the M0 macrophages to gather and polarize to the M1 phenotype at the damaged site through recruitment, adhesion, migration, and activation, leading to ALI. Afterward, M1 macrophages polarize into the M2 phenotype, and then transform into myofibroblasts, followed by enhanced secretion of various anti-inflammatory cytokines and profibrotic cytokines, to promote PF. Our study provides an insight into the pathogenesis of virus-induced ALI and PF, which will assist in the development of therapeutic strategies and drugs for treating influenza and other respiratory virus infections.

Developing Cell-Membrane-Associated Liposomes for Liver Diseases

Over the past decade, a marked escalation in the prevalence of hepatic pathologies has been observed, adversely impacting the quality of life for many. The predominant therapeutic strategy for liver diseases has been pharmacological intervention; however, its efficacy is often constrained. Currently, liposomes are tiny structures that can deliver drugs directly to targeted areas, enhancing their effectiveness. Specifically, cell membrane-associated liposomes have gained significant attention. Despite this, there is still much to learn about the binding mechanism of this type of liposome. Thus, this review comprehensively summarizes relevant information on cell membrane-associated liposomes, including their clinical applications and future development directions. First, we will briefly introduce the composition and types of cell membrane-associated liposomes. We will provide an overview of their structure and discuss the various types of liposomes associated with cell membranes. Second, we will thoroughly discuss various strategies of drug delivery using these liposomes. Lastly, we will discuss the application and clinical challenges associated with using cell membrane-associated liposomes in treating liver diseases. We will explore their potential benefits while also addressing the obstacles that need to be overcome. Furthermore, we will provide prospects for future development in this field. In summary, this review underscores the promise of cell membrane-associated liposomes in enhancing liver disease treatment and highlights the need for further research to optimize their utilization. In summary, this review underscores the promise of cell membrane-associated liposomes in enhancing liver disease treatment and highlights the need for further research to optimize their utilization.

Exploring the Relationship Between Different Obesity Metabolism Indices and Hyperuricemia in Patients with Hypertension and Coronary Heart Disease

Background

Previous studies have established a strong association between obesity, high metabolism, and the development of hyperuricemia. However, the relationship between obesity metabolism indices and hyperuricemia in high-risk patients with hypertension and coronary heart disease (CHD) remains unclear. The purpose of this study was to investigate this relationship in patients with both hypertension and CHD, and to identify the obesity metabolism index with the best diagnostic value.

Methods

A two-center study encompassed 6344 participants with hypertension and CHD. Multiple logistic regression was utilized to examine the correlation between six obesity metabolism indices and hyperuricemia, with restricted cubic spline (RCS) analysis to identify non-linear relationships. Diagnostic value was assessed via receiver operating characteristic (ROC) curves and decision curve analysis (DCA).

Results

Multivariable logistic regression revealed a significant correlation between increased obesity metabolism indices and hyperuricemia. Furthermore, RCS analysis revealed a nonlinear dose-response relationship (P for nonlinear < 0.001). Moreover, ROC and DCA results showed that METS-VF index, which combined visceral obesity and metabolic parameters, became the most reliable diagnostic tool.

Conclusion

The study underscores a strong association between elevated obesity metabolism indices and hyperuricemia in patients with hypertension and CHD. The METS-VF index, amalgamating visceral obesity and metabolic parameters, emerged as the most reliable diagnostic tool.

Multimodal smart systems reprogramme macrophages and remove urate to treat gouty arthritis

Gouty arthritis is a chronic and progressive disease characterized by high urate levels in the joints and by an inflammatory immune microenvironment. Clinical data indicate that urate reduction therapy or anti-inflammatory therapy alone often fails to deliver satisfactory outcomes. Here we have developed a smart biomimetic nanosystem featuring a 'shell' composed of a fusion membrane derived from M2 macrophages and exosomes, which encapsulates liposomes loaded with a combination of uricase, platinum-in-hyaluronan/polydopamine nanozyme and resveratrol. The nanosystem targets inflamed joints and promotes the accumulation of anti-inflammatory macrophages locally, while the uricase and the nanozyme reduce the levels of urate within the joints. Additionally, site-directed near-infrared irradiation provides localized mild thermotherapy through the action of platinum and polydopamine, initiating heat-induced tissue repair. Combined use of these components synergistically enhances overall outcomes, resulting in faster recovery of the damaged joint tissue.

FeSA‐Ir/Metallene Nanozymes Induce Sequential Ferroptosis‐Pyroptosis for Multi‐Immunogenic Responses Against Lung Metastasis

For cancer metastasis inhibition, the combining of nanozymes with immune checkpoint blockade (ICB) therapy remains the major challenge in controllable reactive oxygen species (ROS) generation for creating effective immunogenicity. Herein, new nanozymes with light-controlled ROS production in terms of quantity and variety are developed by conjugating supramolecular-wrapped Fe single atom on iridium metallene with lattice-strained nanoislands (FeSA-Ir@PF NSs). The Fenton-like catalysis of FeSA-Ir@PF NSs effectively produced •OH radicals in dark, which induced ferroptosis and apoptosis of cancer cells. While under second near-infrared (NIR-II) light irradiation, FeSA-Ir@PF NSs showed ultrahigh photothermal conversion efficiency (𝜂, 75.29%), cooperative robust •OH generation, photocatalytic O2 and 1O2 generation, and caused significant pyroptosis of cancer cells. The controllable ROS generation, sequential cancer cells ferroptosis and pyroptosis, led 99.1% primary tumor inhibition and multi-immunogenic responses in vivo. Most importantly, the inhibition of cancer lung metastasis is completely achieved by FeSA-Ir@PF NSs with immune checkpoint inhibitors, as demonstrated in different mice lung metastasis models, including circulating tumor cells (CTCs) model. This work provided new inspiration for developing nanozymes for cancer treatments and metastasis inhibition.

Ginkgo Biloba Bioactive Phytochemicals against Age-Related Diseases: Evidence from a Stepwise, High-Throughput Research Platform

The seeds of ginkgo biloba L (GB) have been widely used worldwide. This study investigated the bioefficacies of whole GB seed powder (WGP) retaining the full nutrients of ginkgo against aging, atherosclerosis, and fatigue. The experimental results indicated that WGP lowered brain monoamine oxidase and serum malondialdehyde levels, enhanced thymus/spleen indexes, and improved learning ability, and delayed aging in senescent mice. WGP regulated lipid levels and prevented atherosclerosis by reducing triglycerides, lowering low-density lipoprotein cholesterol, increasing high-density lipoprotein cholesterol, and decreasing the atherosclerosis index. WGP improved exercise performance by reducing blood lactate accumulation and extending exhaustive swimming and climbing times, improved energy storage by increasing muscle/liver glycogen levels, and relieved physical fatigue. Network pharmacology analysis revealed 270 potential targets of WGP that play roles in cellular pathways related to inflammation inhibition, metabolism regulation, and anti-cellular senescence, etc. Protein-protein interaction analysis identified 10 hub genes, including FOS, ESR1, MAPK8, and SP1 targets. Molecular docking and molecular dynamics simulations showed that the bioactive compounds of WGP bound well to the targets. This study suggests that WGP exerts prominent health-promoting effects through multiple components, targets, and pathways.

Pyroptotic-Spatiotemporally Selective Delivery of siRNA against Pyroptosis and Autoimmune Diseases

Small-interfering RNAs (siRNAs) offer promising prospects for treating pyroptosis-related autoimmune diseases. However, poor stability and off-target effects during in vivo transportation hinder their practical clinical applications. Precision delivery and adaptive release of siRNAs into inflamed tissues and immune cells could unleash their full therapeutic potential. This study establishes a pyroptotic-spatiotemporally selective siRNA delivery system (PMRC@siGSDME) that selectively targets inflammatory tissues, responds to pyroptosis, and exhibits remarkable therapeutic efficacy against various autoimmune diseases. Novel hybrid nanovesicles (NVs) are designed as a combination of pyroptotic macrophage membranes (PMs) and R8-cardiolipin-containing nanovesicles (RC-NVs). Evidence provides that PM-derived proteins involved in cell-cell interactions and membrane trafficking may contribute to the specificity of NVs to inflammatory tissue. In addition, cardiolipin anchored in the hybrid NVs increases its affinity for activated gasdermin E (GSDME) and achieves pyroptosis-adaptive release of siGSDME for the spatiotemporally selective suppression of immune responses. More importantly, PMRC@siGSDME displays significant anti-inflammatory and therapeutic effects in multiple mouse autoimmune disease models, including arthritis and inflammatory bowel disease (IBD). Collectively, an innovative siRNA delivery strategy precisely tailored for pyroptotic cells has been developed, paving the way for new treatments for autoimmune inflammatory diseases with minimal side effects and wide clinical applicability.

A nanozyme-functionalized bilayer hydrogel scaffold for modulating the inflammatory microenvironment to promote osteochondral regeneration

BACKGROUND

The incidence of osteochondral defects caused by trauma, arthritis or tumours is increasing annually, but progress has not been made in terms of treatment methods. Due to the heterogeneous structure and biological characteristics of cartilage and subchondral bone, the integration of osteochondral repair is still a challenge.

RESULTS

In the present study, a novel bilayer hydrogel scaffold was designed based on anatomical characteristics to imitate superficial cartilage and subchondral bone. The scaffold showed favourable biocompatibility, and the addition of an antioxidant nanozyme (LiMn2O4) promoted reactive oxygen species (ROS) scavenging by upregulating antioxidant proteins. The cartilage layer effectively protects against chondrocyte degradation in the inflammatory microenvironment. Subchondral bionic hydrogel scaffolds promote osteogenic differentiation of rat bone marrow mesenchymal stem cells (BMSCs) by regulating the AMPK pathway in vitro. Finally, an in vivo rat preclinical osteochondral defect model confirmed that the bilayer hydrogel scaffold efficiently promoted cartilage and subchondral bone regeneration.

CONCLUSIONS

In general, our biomimetic hydrogel scaffold with the ability to regulate the inflammatory microenvironment can effectively repair osteochondral defects. This strategy provides a promising method for regenerating tissues with heterogeneous structures and biological characteristics.

[Advances in the Application of Nanozymes in Joint Disease Therapy]

Nanozymes are nanoscale materials with enzyme-mimicking catalytic properties. Nanozymes can mimic the mechanism of natural enzyme molecules. By means of advanced chemical synthesis technology, the size, shape, and surface characteristics of nanozymes can be accurately regulated, and their catalytic properties can be customized according to the specific need. Nanozymes can mimic the function of natural enzymes, including catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx), to scavenge reactive oxygen species (ROS). Reported findings have shown that nanozymes have the advantages of excellent stability, low cost, and adjustable catalytic activity, thereby showing great potential and broad prospects in the application of disease treatment. Herein, we reviewed the advances in the application of nanozymes in the treatment of joint diseases. The common clinical manifestations of joint diseases include joint pain, swelling, stiffness, and limited mobility. In severe cases, joint diseases may lead to joint destruction, deformity, and functional damage, entailing crippling socioeconomic burdens. ROS is a product of oxidative stress. Increased ROS in the joints can induce macrophage M1 type polarization, which in turn induces and aggravates arthritis. Therefore, the key to the treatment of joint diseases lies in ROS scavenging and increasing oxygen (O2) content. Nanozymes have demonstrated promising application potential in the treatment of joint diseases, including rheumatoid arthritis, osteoarthritis, and gouty arthritis. However, how to ensure their biosafety, reduce the toxicity, and increase enzyme activity remains the main challenge in current research. Precise control of the chemical composition, size, shape, and surface modification of nanomaterials is the main development direction for the future.

Macrophage-Biomimetic Nanoplatform-Based Therapy for Inflammation-Associated Diseases

Inflammation-associated diseases are very common clinically with a high incidence; however, there is still a lack of effective treatments. Cell-biomimetic nanoplatforms have led to many breakthroughs in the field of biomedicine, significantly improving the efficiency of drug delivery and its therapeutic implications especially for inflammation-associated diseases. Macrophages are an important component of immune cells and play a critical role in the occurrence and progression of inflammation-associated diseases while simultaneously maintaining homeostasis and modulating immune responses. Therefore, macrophage-biomimetic nanoplatforms not only inherit the functions of macrophages including the inflammation tropism effect for targeted delivery of drugs and the neutralization effect of pro-inflammatory cytokines and toxins via membrane surface receptors or proteins, but also maintain the functions of the inner nanoparticles. Macrophage-biomimetic nanoplatforms are shown to have remarkable therapeutic efficacy and excellent application potential in inflammation-associated diseases. In this review, inflammation-associated diseases, the physiological functions of macrophages, and the classification and construction of macrophage-biomimetic nanoplatforms are first introduced. Next, the latest applications of different macrophage-biomimetic nanoplatforms for the treatment of inflammation-associated diseases are summarized. Finally, challenges and opportunities for future biomedical applications are discussed. It is hoped that the review will provide new ideas for the further development of macrophage-biomimetic nanoplatforms.

Expanded ROS Generation and Hypoxia Reversal: Excipient-free Self-assembled Nanotheranostics for Enhanced Cancer Photodynamic Immunotherapy

The efficacy of photodynamic therapy (PDT)-related cancer therapies is significantly restricted by two irreconcilable obstacles, i.e., low reactive oxygen species (ROS) generation capability and hypoxia which constrains the immune response. Herein, this work develops a self-assembled clinical photosensitizer indocyanine green (ICG) and the HSP90 inhibitor 17-dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG) nanoparticles (ISDN) without any excipient. This work discovers that the hydrophobic interaction forces between ICG and 17-DMAG promote the photostability of ICG and its intersystem crossing (ISC) process, thereby improving the ROS quantum yield from 0.112 to 0.46. Augmented ROS generation enhances PDT efficacy and further enhances immunogenic cell death (ICD) effects. 17-DMAG inhibits the HSP90/hypoxia-inducible factor 1α (HIF-1α) axis to dramatically reverse the immunosuppressive tumor microenvironment caused by PDT-aggravated hypoxia. In a mouse model of pancreatic cancer, ISDN markedly improve cytotoxic T lymphocyte infiltration and MHC I and MHC II activation, demonstrating the superior ICD effects in situ tumor and the powerful systematic antitumor immunity generation, eventually achieving vigorous antitumor and recurrence resistance. This study proposes an unsophisticated and versatile strategy to significantly improve PDT efficacy for enhancing systemic antitumor immunity and potentially extending it to multiple cancers.

Potentiating dual-directional immunometabolic regulation with nanomedicine to enhance anti-tumor immunotherapy following incomplete photothermal ablation

Photothermal therapy (PTT) is a promising cancer treatment method due to its ability to induce tumor-specific T cell responses and enhance therapeutic outcomes. However, incomplete PTT can leave residual tumors that often lead to new metastases and decreased patient survival in clinical scenarios. This is primarily due to the release of ATP, a damage-associated molecular pattern that quickly transforms into the immunosuppressive metabolite adenosine by CD39, prevalent in the tumor microenvironment, thus promoting tumor immune evasion. This study presents a photothermal nanomedicine fabricated by electrostatic adsorption among the Fe-doped polydiaminopyridine (Fe-PDAP), indocyanine green (ICG), and CD39 inhibitor sodium polyoxotungstate (POM-1). The constructed Fe-PDAP@ICG@POM-1 (FIP) can induce tumor PTT and immunogenic cell death when exposed to a near-infrared laser. Significantly, it can inhibit the ATP-adenosine pathway by dual-directional immunometabolic regulation, resulting in increased ATP levels and decreased adenosine synthesis, which ultimately reverses the immunosuppressive microenvironment and increases the susceptibility of immune checkpoint blockade (aPD-1) therapy. With the aid of aPD-1, the dual-directional immunometabolic regulation strategy mediated by FIP can effectively suppress/eradicate primary and distant tumors and evoke long-term solid immunological memory. This study presents an immunometabolic control strategy to offer a salvage option for treating residual tumors following incomplete PTT.

Macrophage membrane-coated nanoparticles for the treatment of infectious diseases

Infectious diseases severely threaten human health, and traditional treatment techniques face multiple limitations. As an important component of immune cells, macrophages display unique biological properties, such as biocompatibility, immunocompatibility, targeting specificity, and immunoregulatory activity, and play a critical role in protecting the body against infections. The macrophage membrane-coated nanoparticles not only maintain the functions of the inner nanoparticles but also inherit the characteristics of macrophages, making them excellent tools for improving drug delivery and therapeutic implications in infectious diseases (IDs). In this review, we describe the characteristics and functions of macrophage membrane-coated nanoparticles and their advantages and challenges in ID therapy. We first summarize the pathological features of IDs, providing insight into how to fight them. Next, we focus on the classification, characteristics, and preparation of macrophage membrane-coated nanoparticles. Finally, we comprehensively describe the progress of macrophage membrane-coated nanoparticles in combating IDs, including drug delivery, inhibition and killing of pathogens, and immune modulation. At the end of this review, a look forward to the challenges of this aspect is presented.

Atomic Engineering of Single-Atom Nanozymes for Biomedical Applications

Single-atom nanozymes (SAzymes) showcase not only uniformly dispersed active sites but also meticulously engineered coordination structures. These intricate architectures bestow upon them an exceptional catalytic prowess, thereby captivating numerous minds and heralding a new era of possibilities in the biomedical landscape. Tuning the microstructure of SAzymes on the atomic scale is a key factor in designing targeted SAzymes with desirable functions. This review first discusses and summarizes three strategies for designing SAzymes and their impact on reactivity in biocatalysis. The effects of choices of carrier, different synthesis methods, coordination modulation of first/second shell, and the type and number of metal active centers on the enzyme-like catalytic activity are unraveled. Next, a first attempt is made to summarize the biological applications of SAzymes in tumor therapy, biosensing, antimicrobial, anti-inflammatory, and other biological applications from different mechanisms. Finally, how SAzymes are designed and regulated for further realization of diverse biological applications is reviewed and prospected. It is envisaged that the comprehensive review presented within this exegesis will furnish novel perspectives and profound revelations regarding the biomedical applications of SAzymes.

Ameliorative Effect of Morinda Officinalis Oligosaccharides on LPS-Induced Acute Lung Injury

Acute lung injury (ALI) is a disease characterized by extensive lung damage and rampant inflammation, with a high mortality rate and no effective treatments available. Morinda officinalis oligosaccharides (MOOs), derived from the root of the traditional Chinese medicinal herb Morinda officinalis, known for its immune-boosting properties, presents a novel therapeutic possibility. To date, the impact of MOOs on ALI has not been explored. Our study aimed to investigate the potential protective effects of MOOs against ALI and to uncover the underlying mechanisms through an integrated approach of network pharmacology, molecular docking, and experimental validation. We discovered that MOOs significantly mitigated the pathological damage and decreased the expression of pro-inflammatory cytokines in LPS-induced ALI in mice. Complementary in vitro studies further demonstrated that MOOs effectively attenuated the M1 polarization induced by LPS. Network pharmacology analysis identified HSP90AA1, HSP90AB1, and NF-κB as key overlapping targets within a protein-protein interaction (PPI) network. Furthermore, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses elucidated the biological processes and signaling pathways implicated in MOOs' therapeutic action on ALI. Subsequently, molecular docking affirmed the binding of MOOs to the active sites of these identified targets. Corroborating these findings, our in vivo and in vitro experiments consistently demonstrated that MOOs significantly inhibited the LPS-induced upregulation of HSP90 and NF-κB. Collectively, these findings suggest that MOOs confer protection against ALI through a multi-target, multi-pathway mechanism, offering a promising new therapeutic strategy to mitigate this severe pulmonary condition.

Targeted delivery of MerTK protein via cell membrane engineered nanoparticle enhances efferocytosis and attenuates atherosclerosis in diabetic ApoE-/- Mice

BACKGROUND

Clearance of apoptotic cells by efferocytosis is crucial for prevention of atherosclerosis progress, and impaired efferocytosis contributes to the aggravated atherosclerosis.

RESULTS

In this study, we found that diabetic ApoE-/- mice showed aggravated atherosclerosis as hyperglycemia damaged the efferocytosis capacity at least partially due to decreased expression of Mer tyrosine kinase (MerTK) on macrophages. To locally restore MerTK in the macrophages in the plaque, hybrid membrane nanovesicles (HMNVs) were thus developed. Briefly, cell membrane from MerTK overexpressing RAW264.7 cell and transferrin receptor (TfR) overexpressing HEK293T cell were mixed with DOPE polymers to produce nanovesicles designated as HMNVs. HMNVs could fuse with the recipient cell membrane and thus increased MerTK in diabetic macrophages, which in turn restored the efferocytosis capacity. Upon intravenous administration into diabetic ApoE-/- mice, superparamagnetic iron oxide nanoparticles (SMN) decorated HMNVs accumulated at the aorta site significantly under magnetic navigation, where the recipient macrophages cleared the apoptotic cells efficiently and thus decreased the inflammation.

CONCLUSIONS

 Our study indicates that MerTK decrease in macrophages contributes to the aggravated atherosclerosis in diabetic ApoE-/- mice and regional restoration of MerTK in macrophages of the plaque via HMNVs could be a promising therapeutic approach.

Engineered Cell Membrane-Camouflaged Nanomaterials for Biomedical Applications

Recent strides in nanomaterials science have paved the way for the creation of reliable, effective, highly accurate, and user-friendly biomedical systems. Pioneering the integration of natural cell membranes into sophisticated nanocarrier architectures, cell membrane camouflage has emerged as a transformative approach for regulated drug delivery, offering the benefits of minimal immunogenicity coupled with active targeting capabilities. Nevertheless, the utility of nanomaterials with such camouflage is curtailed by challenges like suboptimal targeting precision and lackluster therapeutic efficacy. Tailored cell membrane engineering stands at the forefront of biomedicine, equipping nanoplatforms with the capacity to conduct more complex operations. This review commences with an examination of prevailing methodologies in cell membrane engineering, spotlighting strategies such as direct chemical modification, lipid insertion, membrane hybridization, metabolic glycan labeling, and genetic engineering. Following this, an evaluation of the unique attributes of various nanomaterials is presented, delivering an in-depth scrutiny of the substantial advancements and applications driven by cutting-edge engineered cell membrane camouflage. The discourse culminates by recapitulating the salient influence of engineered cell membrane camouflage within nanomaterial applications and prognosticates its seminal role in transformative healthcare technologies. It is envisaged that the insights offered herein will catalyze novel avenues for the innovation and refinement of engineered cell membrane camouflaged nanotechnologies.

Anti-Acidification and Immune Regulation by Nano-Ceria-Loaded Mg-Al Layered Double Hydroxide for Rheumatoid Arthritis Therapy

Rheumatoid arthritis (RA) is a chronic autoimmune disease featuring an abnormal immune microenvironment and resultant accumulation of hydrogen ions (H+ ) produced by activated osteoclasts (OCs). Currently, clinic RA therapy can hardly achieve sustained or efficient therapeutic outcomes due to the failures in generating sufficient immune modulation and manipulating the accumulation of H+ that deteriorates bone damage. Herein, a highly effective immune modulatory nanocatalytic platform, nanoceria-loaded magnesium aluminum layered double hydroxide (LDH-CeO2 ), is proposed for enhanced immune modulation based on acid neutralization and metal ion inherent bioactivity. Specifically, the mild alkaline LDH initiates significant M2 repolarization of macrophages triggered by the elevated antioxidation effect of CeO2 via neutralizing excessive H+ in RA microenvironment, thus resulting in the efficient recruitment of regulatory T cell (Treg) and suppressions on T helper 17 cell (Th 17) and plasma cells. Moreover, the osteogenic activity is stimulated by the Mg ion released from LDH, thereby promoting the damaged bone healing. The encouraging therapeutic outcomes in adjuvant-induced RA model mice demonstrate the high feasibility of such a therapeutic concept, which provides a novel and efficient RA therapeutic modality by the immune modulatory and bone-repairing effects of inorganic nanocatalytic material.