Inflammatory bowel disease (IBD) is characterized by a hostile intestinal microenvironment involving excessive oxidative stress, epithelial barrier disruption, and gut microbiota dysbiosis. However, effective strategies for achieving sustained mucosal healing and long-term remission remain limited. Here, we report a dual-layer engineered probiotic (designed as EcN@PDA@MPN) via a two-step one-pot surface engineering strategy that sequentially integrates a polydopamine (PDA) layer and zinc-tannic acid metal-phenolic networks (MPN) onto Escherichia coli Nissle 1917. The inner PDA layer provides a biocompatible adhesive scaffold that stabilizes the bacterial surface and facilitates subsequent interfacial assembly, while the outer MPN shell offers dense, stimuli-responsive shielding against harsh gastrointestinal conditions and enables controlled release of bioactive zinc ions. This composite coating markedly enhances probiotic stability against gastric acid, digestive enzymes, and inflammatory oxidative stress, while preserving bacterial viability. In the dextran sulfate sodium-induced murine colitis model, oral administration of EcN@PDA@MPN significantly alleviated disease severity, as evidenced by reduced weight loss, preservation of colon length, and improved histopathological outcomes. Mechanistically, transcriptomic and microbiome analyses revealed that EcN@PDA@MPN exerts a triple therapeutic action, including suppressing pro-inflammatory signaling pathways and cytokines, restoring intestinal epithelial barrier integrity via upregulation of tight-junction proteins, and reshaping gut microbiota composition by enriching beneficial commensals while inhibiting pathobionts. In addition, EcN@PDA@MPN exhibited enhanced intestinal retention and preferential accumulation in inflamed colonic regions with no observable systemic toxicity. This work establishes a probiotic engineering paradigm that integrates protection, targeting, and microenvironment modulation for IBD treatment.

Immune cell engineering, exemplified by chimeric antigen receptor T (CAR-T) cell therapy, has revolutionized the treatment of various diseases, particularly cancers. While significant advancements have been made in ex vivo immune cell editing, progress in in vivo engineering has been comparatively slower despite its substantial potential advantages, such as reduced manufacturing complexity and cost. However, in vivo approaches face critical challenges, including insufficient targeting specificity, limited editing efficiency, and uncertain long-term safety profiles. These limitations necessitate the exploration of nano-strategies to overcome biological barriers. This review summarizes the advantages of in vivo over ex vivo immune cell engineering, discusses the latest research progress in nano-therapeutics for in vivo immune cell engineering, and highlights applications across diverse diseases. Finally, we examine critical barriers hindering clinical translation and offer perspectives on future developments.

Triple-negative breast cancer establishes a stromal-metabolic barrier, characterized by dense fibrosis and metabolic dysregulation, to induce immunotherapy resistance. To dismantle this barrier, we propose a Programmable Rewiring of Immuno-Stromal Metabolism (PRISM) strategy, supported by a POD-like activity-oriented machine learning (ML) screening of representative catalytic metals. A metabolic nanoregulator, Au@Fe-Co@HA (ACFH), was engineered to couple glucose starvation with Fe/Co-mediated oxidative therapy. The Au core of ACFH acted as a glucose oxidase-like enzyme to deplete glucose and generate endogenous H2O2, thereby powering the peroxidase-like activity of the iron-cobalt (Fe/Co) shell. In vivo, ACFH-mediated combined therapy reduced GLUT1 expression in tumor tissues and suppressed glucose uptake and glycolysis-associated metabolic activity. The GSH-responsive release of Fe/Co ions disrupted redox homeostasis and activated immunogenic cell death (ICD), facilitating dendritic cell maturation, M1 macrophage polarization, and CD4+/CD8+ T-cell infiltration. When combined with immune checkpoint blockade, the therapeutic efficacy was further enhanced. In this study, ML was used to translate the therapeutic requirement for ROS-amplified ferroptosis and immunogenic therapy into a quantifiable catalytic screening endpoint. By integrating this function-oriented metal selection with the PRISM strategy, this work provides a rational nanoregulator design to overcome stromal-metabolic resistance in TNBC.

Chemo-immunotherapy aims to integrate chemotherapy-induced antigen release with innate immune activation to achieve enhanced antitumor efficacy. However, the pharmacokinetic mismatch and systemic toxicity of free small molecules often compromise the synergistic effects. Herein, we propose a reactive oxygen species (ROS)-responsive nanoplatform based on mPEG-PCL for the co-delivery of a paclitaxel (PTX) prodrug and the TLR7/8 agonist R848. The nanoparticles remain stable under physiological conditions while releasing the drug in oxidative tumor microenvironments, thereby achieving synchronous intratumoral delivery and activation. In vitro, the system exhibited efficient intracellular uptake and potent cytotoxicity against tumor cells while maintaining low toxicity toward normal cells due to prodrug design. Moreover, the platform effectively induced immunogenic cell death and promoted dendritic cell maturation, highlighting its capacity for chemo-immunotherapeutic synergy. This co-delivery strategy provides a versatile approach to realize controllable and safe chemo-immunotherapy through stimuli-responsive nanomedicine design.

The synergistic strategy combining chemotherapy and immunotherapy has recently demonstrated significant promise in cancer treatment. However, the substantial physicochemical disparities between chemotherapeutic agents and small-molecule immune adjuvants pose considerable challenges for co-delivery strategies. In this study, we designed a reactive oxygen species-responsive paclitaxel prodrug, PTX-PBA, which markedly enhanced drug encapsulation stability and dual-drug loading efficiency by various polymeric delivery systems. The resultant nanosystem (NanoPR) exhibited excellent physicochemical properties and ROS-triggered release profiles, effectively inducing immunogenic cell death in tumor cells while promoting dendritic cell maturation and CD8+ T cells activation. In murine models of 4T1 breast cancer and CT26 colon carcinoma, NanoPR achieved significant tumor growth inhibition and elicited durable immune memory responses. Collectively, this work provides an innovative molecular design strategy for the co-delivery of chemotherapeutics and immunomodulators, offering a robust foundation for the clinical translation of chemo-immunotherapy.

Melittin, the principal bioactive component of bee venom, exhibits potent anticancer activity. However, its clinical application is hindered by nonspecific hemolytic toxicity. In this study, we developed a pH-responsive polymeric-peptide complex (PCM) to improve anti-tumor activity of melittin while minimizing off-target effects. PCM remained structurally stable under physiological conditions (pH 7.4) but underwent rapid disassembly in the mildly acidic tumor microenvironment (pH 6.8) to expose melittin. The exposed melittin bound to tumor cell membranes, compromised membrane integrity through transmembrane pore formation, leading to tumor cell death. This membrane disruption elicited the release of damage-associated molecular patterns, thereby activating antitumor immune responses. In a murine breast cancer model, low dose administration of PCM significantly inhibited tumor recurrence and metastasis, and generated durable antitumor immunological memory without significant side effects. The mechanistic actions and morphological effects of PCM on tumor cells were thoroughly investigated, providing important theoretical insights for the clinical translation of anticancer peptides.

The efficacy of cancer vaccines is often limited by poor cytosolic antigen delivery. Here, we report a pH-responsive copolymer nanovaccine that remains inert under physiological conditions yet undergoes acid-triggered activation within endosomes. This activation induces membrane disruption and rapid antigen release, enhances endosomal escape, thereby enabling efficient cytosolic antigen delivery. These result in greatly enhanced antigen cross-presentation and dendritic cell maturation, which together drive strong activation and effector differentiation of antigen-specific CD8⁺ T cells. Through this approach the nanovaccine elicited strong cellular immunity and achieved marked tumor suppression with favorable biocompatibility across multiple murine tumor models. This work collectively provides a generalized, yet flexible strategy that overcomes the endosomal escape bottleneck and improves cytosolic antigen delivery for next-generation cancer vaccines. Statement of Significance (i) a mechanistically supported approach to improve endosomal escape for cytosolic antigen delivery; (ii) a polymer design framework that can be adapted to antigen delivery applications; (iii) in vivo evidence linking nanoscale material behavior to systemic antitumor immune responses.

Polymer networks possess numerous elastically defective and isolated loops, which do not contribute to mechanical stiffness. In this report, we introduce a strategy of supramolecular topological linking to access stiffer-yet-ductile polymeric materials through incorporation of supramolecular tetravalent crosslinkers. Dynamic dissociation/re-association between these high-functionality crosslinks enables the formation of topologically-linked loops that serve as elastic springs to stiffen the networks. An exceptional scaling exponent of 2.05 for Young's modulus versus crosslinker concentration is obtained, exceeding most reported randomly-crosslinked polymeric systems. Compared to conventional analogs, the mechanical properties of the resultant materials are enhanced: Young's modulus (2-fold), elongation at break (8-fold), and work of fracture (100-fold). Uplifting modulus scalings through supramolecular topological linking paves a new path to the design of stiffness-reinforced soft materials, holding substantial promise in load-bearing application scenarios such as tissue implants, bioelectronic interfaces, and soft robotics.

In situ cancer vaccines hold strong potential for addressing tumor heterogeneity by using the patient’s own tumor as a personalized antigen source. However, their efficacy remains limited by insufficient antigen capture and inefficient cytosolic delivery. Here, we report an in situ antigen capture and delivery platform, DOX/PDiT@Gel, in which the pH-responsive function is provided by the polymer PDiT, while the hydrogel serves as a local retention matrix. In this system, doxorubicin (DOX) and a cationic polymer, PEG-DIPAMA-TAT (PDiT), are co-encapsulated within an oxidized dextran/carboxymethyl chitosan hydrogel. DOX induces immunogenic cell death, releasing diverse tumor antigens, while PDiT captures these antigens in situ via electrostatic interactions and promotes endo/lysosomal escape under acidic conditions. The hydrogel allows localized delivery of the therapeutic components at the postoperative tumor site. In vitro studies showed that PDiT markedly promoted antigen internalization, cross-presentation, and dendritic cell maturation. In murine models of postoperative recurrence and bilateral breast tumors, local treatment with DOX/PDiT@Gel inhibited the growth of both recurrent and distant tumors, together with stronger dendritic cell activation and enhanced memory T cell responses. Overall, this platform effectively amplifies antitumor immunity and offers a versatile strategy for personalized cancer immunotherapy.

Natural load-bearing tissues such as tendon exhibit both high stiffness and toughness owing to their densely packed, hierarchical architectures. However, most synthetic hydrogels suffer from biomechanical mismatch and lack of biocompatibility, which restrict their utility in tendon-related therapy. In this work, we report a set of glassy, poly(vinyl alcohol) hydrogels, stiffened and toughened through salting-out with a super-kosmotropic salt, sodium hexametaphosphate. The highly-charged anion displays an exceptional B-coefficient of 1.408 L mol-1 with remarkable kosmotropic effect, which not only promotes the formation of crystalline domains but also immobilizes free water molecules within gel networks. The resultant materials are endowed with substantially enhanced stiffness, toughness and fracture energy of 1061.8 MPa, 548.5 MJ m-3, and 272.5 kJ m-2, respectively, matching those of native tendons. Utilizing these hydrogels as biomechanical scaffolds in a tendon-ruptured rat model demonstrate high efficacy in both morphological and functional recovery. Salting-out biopolymers with super-kosmotropic agents enlightens the design and construction of stiff-yet-tough biomaterials, holding great promise for biomedical applications in regenerative and reparative therapies of natural load-bearing tissues.

Current tissue adhesives struggle with wet adhesion and phased treatment during coagulation‐healing transitions. Here, we developed a mechano‐adaptive PAA‐NHS/PEI/Fibrin (PNPF) powder adhesive featuring a dual‐network architecture, integrating a polyelectrolyte matrix (PAA‐NHS/PEI) and fibrin network through chemical linkages and thrombin activation, which displayed remodeling ability after fragmentation of the network. Benefitting from the combination of the two networks, PNPF powder adhesive exhibited water‐absorbent self‐gelation capability and bioactive properties, encompassing both procoagulant and prohealing abilities. More concretely, the powder adhesive exhibited ultrafast and robust sealing on biological tissues via interfacial dehydration and interface coupling, with the burst pressure achieving 180.7 mmHg. By integrating its superior coagulation‐enhancing properties, the PNPF powder adhesive demonstrated notably accelerated hemostatic efficacy in both rat tail and liver injury models compared to conventional hemostatic products. Furthermore, the adhesive substantially accelerated posthemostasis tissue repair processes, establishing itself as a viable strategy for advanced wound care management.

Hypoxia is a hallmark of the solid tumor microenvironment and a key factor limiting therapeutic efficacy in osteosarcoma (OS), as it can promote chemoresistance and impair reactive oxygen species generation during sonodynamic therapy (SDT). Current strategies to alleviate tumor hypoxia, however, remain limited by insufficient endogenous oxygen production and inefficient exogenous oxygen delivery. To address this, we developed a tumor-targeted polymeric nanoplatform designed to relieve hypoxia. An oxygen-delivery system, named PPFCD, was constructed using a fluorine-rich block as an oxygen reservoir and phenylboronic acid side chains for efficient co-loading of doxorubicin (DOX) and chlorin e6 (Ce6). The oxygen carried by the fluorinated segments effectively mitigated intratumoral hypoxia. Upon ultrasound irradiation, PPFCD exhibited a strong sonodynamic effect, which, combined with the high DOX load, led to synergistic chemo-sonodynamic antitumor activity. In an orthotopic OS mouse model, this nanoplatform increased oxygen saturation by ∼10%, inhibited tumor growth by ∼90%, and triggered robust innate and adaptive immune responses. In summary, this study presents a polymeric nanoplatform capable of tumor-specific co-delivery of oxygen and drugs, offering important insights into overcoming the challenges of SDT for solid tumors. STATEMENT OF SIGNIFICANCE: Polymeric Drug Delivery System: A polymeric carrier is employed to co-load an antitumor agent (doxorubicin, DOX), a sonosensitizer (chlorin e6, Ce6), and oxygen, enabling the simultaneous delivery of multiple therapeutic components. Multi-Action Anti-Tumor Platform: The platform incorporates pendant phenylboronic acid (PBA) that enables nitrogen-boron coordination with DOX and hydrophobic interactions with Ce6, together with a fluorine-containing block with high oxygen affinity. Highly Effective Antitumor Activity: The platform elicits strong innate and adaptive immune responses and markedly inhibits osteosarcoma progression, with tumor volumes reduced to approximately 20% of those in the control group. Clinical Application Potential: This platform features a simple formulation, with key components including DOX, Ce6, and polyethylene glycol (PEG), all of which have been approved by the FDA. It demonstrates substantial therapeutic potential in osteosarcoma and shows promising prospects for future clinical translation.

Current treatments for osteoporosis and osteoporotic fractures, such as bisphosphonates and teriparatide, are limited by poor bone-targeting and systemic toxicity. To address these issues, we developed a bone-targeted nanodelivery platform (FPBE) by encapsulating beta-glycerophosphate (beta-GP) in a fluorinated polyethylenimine carrier. The platform was further functionalized with the E7 peptides to enhance the affinity for mesenchymal stem cells (MSCs) and improve bone marrow targeting. Biocompatibility and delivery efficiency were optimized by the degree of screening fluorination. Single-cell RNA sequencing revealed that FPBE upregulates Wnt/beta-catenin, driving MSC osteogenic and chondrogenic differentiation to support regenerative processes. In postmenopausal mice, systemic FPBE increased bone mineral density (BMD), matching zoledronic acid levels with fewer side effects. In non-human primates, FPBE increased BMD by 83.07% (males) and 55.92% (females), with serum analyses confirming its efficacy and safety. This nanoplatform-which delivers beta-GP to restore phosphate balance-provides a cost-effective therapy for osteoporosis and osteoporotic fracture repair, with strong potential for clinical application.

Adoptive natural killer (NK) cell therapy is often hindered by multiple immune resistance mechanisms within the solid tumor microenvironment (TME), necessitating the development of multifunctional NK cells. Here, we present a fusogenic liposome (Flip)-engineered NK (Flip/NK) cell to counteract these immunosuppressive challenges. By fusing with the NK cell membrane, Flip delivers a transforming growth factor β receptor I (TGF-βRI) inhibitor, galunisertib (GST), into the NK cytoplasm, while simultaneously anchoring phenylboronic acid (PBA)-modified lipids onto the NK surface. The cytoplasmic GST effectively inhibits the intracellular TGF-β signaling pathway, enhancing NK cell resistance to TGF-β-induced immunosuppression in the TME. Meanwhile, surface-bound PBA targets tumor-associated sialic acids, improving NK cell recognition and alleviating inhibitory signals. Upon reinfusion into mice, Flip/NK efficiently suppressed SNU449, HepG2-Luc, and 4T1-Luc tumor growth, even activating T cell immunity for synergetic antitumor effects. This Flip/NK strategy offers a promising approach for personalized and multiplexed NK cell engineering to enhance adoptive cell immunotherapy against solid tumors.

Immunotherapy with immune checkpoint inhibitors has revolutionized cancer treatment, yet many tumors evade immune surveillance through multiple suppressive mechanisms. In particular, the adaptive immune checkpoint programmed death 1 (PD-1)/programmed death-ligand 1 (PD-L1) and the innate "don't eat me" signal CD47/signal-regulatory protein alpha (SIRPα) represent two distinct pathways that cancers exploit to avoid T-cell attack and macrophage phagocytosis, respectively. Herein, we present BITE (Biomimetic Immune Targeting and Editing), a genetically engineered biomimetic nanoplatform designed to concurrently blockade both pathways by combining PD-1-mediated tumor targeting with CRISPR/Cas9 gene editing of CD47. BITE nanovesicles display PD-1 on their surface, enabling selective binding to PD-L1-expressing tumor cells and local disruption of PD-1/PD-L1 signaling. Simultaneously, they deliver a CRISPR/Cas9 payload that knocks out the CD47 gene in tumor cells, abolishing the anti-phagocytic signal and thus activating innate immune clearance. We demonstrate that BITE efficiently homes to PD-L1-positive tumors in vitro and in vivo, achieves significant CD47 gene disruption in tumor cells, and triggers robust phagocytosis by macrophages. In a mouse tumor model, dual checkpoint blockade by BITE reshapes the tumor microenvironment, yielding increased infiltration of CD4+ T cells, CD8+ T cells, and M1 macrophages; treatment with BITE induces pronounced tumor regression and extended survival, outperforming single-target controls. Our results establish a proof-of-concept for this dual-function nanovesicle approach, highlighting its potential to engage both adaptive and innate immunity synergistically. The BITE platform offers a versatile and targeted strategy to overcome immune resistance in cancer, representing a promising therapeutic avenue in biomedical engineering and nanomedicine.

Sonodynamic therapy (SDT) is an emerging modality for cancer treatment that induces immunogenic cell death (ICD) through reactive oxygen species (ROS) generation, thereby triggering potent antitumor immunity. However, the hypoxic and glutathione (GSH)-rich tumor microenvironment restricts ROS production, while dense extracellular matrix (ECM) formed by cancer-associated fibroblasts (CAFs) further impedes immune cell infiltration. Here, we developed a hydrogel-based localized delivery platform co-encapsulating the nano-sonosensitizer PCN-224@MnO2@HA (PMH), and SIS3, a SMAD3 inhibitor. Upon hydrogel-mediated local administration, MnO2 catalyzes O2 generation from endogenous hydrogen peroxide while depleting intracellular GSH, thereby amplifying ROS production during SDT. Concurrently, SIS3 reprograms CAFs by blocking TGF-β/SMAD3 signaling, reducing collagen deposition and promoting immune cell infiltration. In an osteosarcoma mouse model, the combination of PMH-mediated SDT with SIS3-induced CAF reprogramming reduced collagen deposition by approximately 50 % and triggered robust antitumor immune responses, which collectively contributed to a 76 % inhibition of tumor growth. Collectively, this study demonstrates a novel CAF-targeted SDT strategy integrating ECM remodeling, ROS enhancement, and localized delivery, offering a promising therapeutic paradigm for solid tumor treatment.

In liquid biopsy, extracellular vesicles (EVs) have emerged as promising biomarkers due to their ability to carry protected nucleic acids. In particular, DNA enclosed within these vesicles shows great diagnostic potential for monitoring oncovirus-related disease progression. However, current methods still require labor-intensive procedures and bulk analysis. Additionally, in situ detection from blood is hindered by abundant serum proteins, interfering with the accuracy of diagnosis. To address these limitations, we developed an antifouling fusion-mediated CRISPR/Cas detector (AFFECTOR) as a user-friendly and efficient diagnostic platform for directly detecting EV-contained viral DNA in serum samples. Leveraging zwitterionic phosphatidylcholine to resist protein interference, the platform enables stable membrane fusion with intact EVs even in serum-containing environments, allowing highly specific and sensitive detection of internal DNA via the CRISPR/Cas12a sensing system, lasting just 2 h at 37 °C. In clinical samples from oncovirus-infected patients and healthy donors, the platform achieved one-step detection of viral DNA-positive EVs. Notably, viral DNA in circulating EVs was found for the first time to correlate with oncovirus infection stages. Overall, this platform provides a practical tool for diagnostic applications and expands the detection window in liquid biopsy.