Inhibition of post-surgery tumour recurrence via a hydrogel releasing CAR-T cells and anti-PDL1-conjugated platelets

Injectable oxidized high-amylose starch hydrogel scaffold for macrophage-mediated glioblastoma therapy

Glioblastoma, characterized by rapid proliferation and invasiveness, is largely resistant to current treatment modalities. A major obstacle is the blood-brain barrier (BBB), which restricts the delivery of therapeutic agents as well as the infiltration of effective immune cells into glioblastoma. In this study, we developed an injectable oxidized high-amylose starch hydrogel (OHASM) to serve as a biomaterial scaffold for the delivery of macrophages and macrophage-polarizing drugs, aiming to bypass the BBB and enhance glioblastoma treatment. The in vitro and in vivo experiments confirmed the efficacy of the hydrogel in loading and delivering macrophages and polarizing drugs against glioblastoma. Additionally, the hydrogel's interconnected porous structure was conducive to cellular growth and activity, and its slow release of therapeutics contributed to the extended survival of treated mice in a mouse GL261 glioblastoma tumor model. The immunological mechanisms underlying the therapeutic efficacy were further elucidated, revealing the potential of the hydrogel system to modulate macrophage polarization and induce apoptosis in tumor cells via the poly ADP-ribose polymerase (PARP) pathway. The study underscores the potential of the hydrogel-based macrophage delivery strategy as an effective and safe treatment for glioblastoma, offering a promising avenue for clinical management of this aggressive brain cancer.

Ultrasound-Energized OX40L-Expressing Biohybrid for Multidimensional Mobilization of Sustained T Cell-Mediated Antitumor Immunity and Potent Sono-Immunotherapy

Harnessing immunostimulation to reinvigorate antitumor effector immune cells represents a promising strategy for tumor eradication. However, achieving durable clinical outcomes necessitates multidimensional activation to sustain robust immune responses. Here, we present an ultrasound-empowered living biohybrid that strategically mobilizes T-cell-mediated immunity for potent tumor sono-immunotherapy. Through synthetic biology, we engineer bacteria to express a fusion protein encoding the costimulatory OX40 ligand (OX40L), and further functionalize them with a high-performance polymer sonosensitizer tethered via a reactive oxygen species-cleavable linker. Upon ultrasound irradiation, the sono-activated nanocargoes detach from the bacterial surface, facilitating cellular entry and exposing immune-stimulating OX40L. The potent sonodynamic effects, coupled with the native immunogenicity of bacteria, promotes tumor-associated antigen release, fosters a proinflammatory microenvironment, and drives dendritic cell maturation, thereby priming cytotoxic T-cell activation. The OX40L expressed by the engineered bacteria amplifies and sustains T-cell activity, orchestrating a robust and durable antitumor response. This cascade-amplified immune activation effectively suppresses tumor growth, induces long-lasting immune memory, and provides protection against tumor metastasis and recurrence, significantly enhancing survival outcomes. By integrating ultrasound-energized nanoadjuvants with costimulatory immune boosters, this hybrid living biotherapeutic platform offers a versatile and powerful strategy for multidimensional immune activation, advancing the frontier of cancer sono-immunotherapy.

Tumor Microenvironment Triggered In Situ Coagulation of Supramolecularly Engineered Platelets for Precise Tumor Embolization

Although embolization therapy has demonstrated success in impeding tumor growth, concerns persist regarding potential tumor recurrence and inadvertent embolization of non-target tissues. In this study, drawing inspiration from the natural targeting and coagulation process of platelets in injured blood vessels, platelets are engineered by integrating acid-sensitive, morphology-transformable nanoparticles onto their surface through supramolecular conjugation (PLT-NP). The nanoparticles are constructed through the self-assembly of a β-amyloid derived peptide (FFVLK) terminally functionalized with Fmoc, hexahistidine (His6), and a polyethylene glycol (PEG)-functionalized cyclodextrin (CD). The supramolecularly engineered platelets actively accumulate in the tumor tissue upon inducing a tumor blood vessel injury through tumor resection. In response to the local acidic microenvironment, the nanoparticles undergo a morphological transformation into nanofibers via spontaneous assembly of FFLVK into fibril structures through hydrogen bonding and β-sheet interactions, to artificially enhance the coagulation and aggregation of platelets, causing occlusion of tumor blood vessels. The supramolecularly engineered platelets efficiently embolize tumor blood vessels in a specific manner, effectively suppressing tumor growth, metastasis, and recurrence, thus offering a promising paradigm for combating cancer.

Implantable Immunostimulant Microneedle Patch for Post-Surgical Prevention of Cancer Recurrence and Distant Tumor Inhibition

Cancer recurrence after surgical resection remains a grand challenge in achieving long-term eradication. Here, we develop a biocompatible and implantable immunostimulant microneedle patch designed to suppress local tumor recurrence after surgery. The patch, fabricated using methacrylate-modified hyaluronic acid, incorporates 2'3'-cGAMP, a STING agonist, and IL-2, a cytokine approved for clinical cancer immunotherapy that expands T cells. The patch enables controlled release of cGAMP to induce dendritic cell maturation, antitumor macrophage polarization (M1 macrophage), and T cell priming and activation. Simultaneously, localized IL-2 activates CD8+ T cells and recruits immune cells to the tumor microenvironment. When combined with an anti-CTLA-4 antibody, an immune checkpoint blockade, the hybrid microneedle patch significantly reduces Treg cells at the surgery sites, enhancing immune responses and effectively inhibiting the progression of distant tumors in both prophylactic and therapeutic models. Compared with traditional postsurgical chemotherapy and radiotherapy, this patch-mediated immunotherapy demonstrates superior efficacy in mitigating tumor relapse while offering higher biocompatibility. Our findings suggest that this immunotherapeutic patch has potential as a translational tool to prevent cancer recurrence in patients with resectable tumors.

Improved Efficacy of Triple-Negative Breast Cancer Immunotherapy via Hydrogel-Based Co-Delivery of CAR-T Cells and Mitophagy Agonist

Leaky and structurally abnormal blood vessels and increased pressure in the tumor interstitium reduce the infiltration of CAR-T cells in solid tumors, including triple-negative breast cancer (TNBC). Furthermore, high burden of tumor cells may cause reduction of infiltrating CAR-T cells and their functional exhaustion. In this study, various effector-to-target (E:T) ratio experiments are established to model the treatment using CAR-T cells in leukemia (high E:T ratio) and solid tumor (low E:T ratio). It is found that the antitumor immune response is decreased in solid tumors with low E:T ratio. Furthermore, single cell sequencing is performed to investigate the functional exhaustion at a low ratio. It is revealed that the inhibition of mitophagy-mediated mitochondrial dysfunction diminished the antitumor efficacy of CAR-T-cell therapy. The mitophagy agonist BC1618 is screened via AI-deep learning and cytokine detection, in vivo and in vitro studies revealed that BC1618 significantly strengthened the antitumor response of CAR-T cells via improving mitophagy. Here, injection hydrogels are engineered for the controlled co-delivery of CAR-T cells and BC1618 that improves the treatment of TNBC. Local delivery of hydrogels creates an inflammatory and mitophagy-enhanced microenvironment at the tumor site, which stimulates the CAR-T cells proliferation, provides antitumor ability persistently, and improves the effect of treatment.

A syringeable immunotherapeutic hydrogel enhances T cell immunity via in-situ activation of STING pathway for advanced breast cancer postoperative therapy

Complete surgical resection of advanced breast cancer is highly challenging and often leaves behind microscopic tumor foci, leading to inevitable relapse. Postoperative formation of the immunosuppressive tumor microenvironment (TME) reduces the efficacy of immunotherapies against residual tumors. Although cytotoxic chemotherapeutics exert the capacity to intensify cancer immunotherapy via immunogenic cell death (ICD) effects, systemically administered chemo agents often cannot access residual tumor sites, and fail to elicit antitumor immune responses. Herein, we present a novel syringeable immunotherapeutic hydrogel (SiGel@SN38/aOX40) loaded with the DNA-targeting chemotherapeutic 7-ethyl-10-hydroxycamptothecin (SN38) and the anti-OX40 agonist antibody (aOX40). The sustained in-site release of SN38 and aOX40 activate the stimulator of interferon genes (STING) pathway, intensify type I interferons expression, synergistically facilitate dendritic cell (DC) activation, and initiate persistent T cell mediated immune responses within the surgical resection bed that eliminate residual tumors with no tumor recurrence in 120 days. Collectively, our designed SiGel@SN38/aOX40 induces robust and long-lasting tumoricidal immunity following breast cancer resection and exhibit immense potential for clinical translation.

SynBioNanoDesign: pioneering targeted drug delivery with engineered nanomaterials

Synthetic biology and nanotechnology fusion represent a transformative approach promoting fundamental and clinical biomedical science development. In SynBioNanoDesign, biological systems are reimagined as dynamic and programmable materials to yield engineered nanomaterials with emerging and specific functionalities. This review elucidates a comprehensive examination of synthetic biology's pivotal role in advancing engineered nanomaterials for targeted drug delivery systems. It begins with exploring the fundamental synergy between synthetic biology and nanotechnology, then highlights the current landscape of nanomaterials in targeted drug delivery applications. Subsequently, the review discusses the design of novel nanomaterials informed by biological principles, focusing on expounding the synthetic biology tools and the potential for developing advanced nanomaterials. Afterward, the research advances of innovative materials design through synthetic biology were systematically summarized, emphasizing the integration of genetic circuitry to program nanomaterial responses. Furthermore, the challenges, current weaknesses and opportunities, prospective directions, and ethical and societal implications of SynBioNanoDesign in drug delivery are elucidated. Finally, the review summarizes the transformative impact that synthetic biology may have on drug-delivery technologies in the future.

Platelets and megakaryocytes in cancer

Platelets have important roles in hemostasis but also actively participate in cancer metastasis and inflammatory processes. They are produced by large precursor cells, the megakaryocytes, residing mainly in the bone marrow. Clinically, elevated platelet counts and/or increased platelet-to-lymphocyte ratio are being explored as biomarkers of metastatic disease and to predict survival or response to therapy in certain cancers. Multiple mechanisms have been put forward on how platelets promote hematogenous metastasis stemming mainly from murine experimental models. Research is now beginning to explore the potential roles of megakaryocytes in solid cancer, myeloma, and lymphoma. Here, we review mechanisms on how platelets and megakaryocytes contribute to cancer progression and metastasis but also discuss potential cancer-suppressing functions mainly related to the regulation of vascular intratumor integrity. Recent developments in cancer immune checkpoint therapy are reviewed with a focus on the potential roles of platelets. Moreover, we review studies exploring platelets for targeted drug delivery systems in cancer therapy.

Immunostimulatory Hydrogel with Synergistic Blockage of Glutamine Metabolism and Chemodynamic Therapy for Postoperative Management of Glioblastoma

Glioblastoma multiforme (GBM) is one of the most lethal malignant brain tumors in the central nervous system. Patients face many challenges after surgery, including tumor recurrence, intracranial pressure increase due to cavitation, and limitations associated with immediate postoperative oral chemotherapy. Here an injected peptide gel with in situ immunostimulatory functions is developed to coordinate the regulation of glutamine metabolism and chemodynamic therapy for overcoming these postoperative obstacles. The methodology entails crafting injectable gel scaffolds with short peptide molecules, incorporating the glutaminase inhibitor CB-839 and copper peptide self-assembled particles (Cu-His NPs) renowned for their chemodynamic therapy (CDT) efficacy. By fine-tuning glutamic acid production via metabolic pathways, this system not only heightens the therapeutic prowess of copper peptide particles in CDT but also escalates intracellular oxidative stress. This dual mechanism culminates in augmented immunogenic cell death within glioblastoma multiforme cells and improves a conducive immune microenvironment. Based on the concept of metabolic reprogramming, this treatment strategy has great potential to significantly reduce GBM tumor recurrence and prolong median survival in murine models.

Recent Advances in Polysaccharide-Based Hydrogels for Tumor Immunotherapy

Immunotherapy has revolutionized cancer treatment and led to a significant increase in patient survival rates and quality of life. However, the effectiveness of current immunotherapies is limited by various factors, including immune evasion mechanisms and serious side effects. Hydrogels are a type of medical material with an ideal biocompatibility, variable structure, flexible synthesis method, and physical properties. Hydrogels have long been recognized and used as a superior choice for various biomedical applications. The fascinating results were derived from both in vitro and in vivo models. The rapid expansion of this area suggests that the principles and uses of functionalized polysaccharides are transformative, motivating researchers to investigate novel polysaccharide-based hydrogels for wider applications. Polysaccharide hydrogels have proven to be a practicable delivery strategy for tumor immunotherapy due to their biocompatibility, biodegradability, and pronounced bioactive characteristics. This study aims to examine in detail the latest developments of polysaccharide hydrogels in tumor immunotherapy, focusing on their design, mechanism of action, and potential therapeutic applications.

Chimeric Antigen Receptor Cells Solid Tumor Immunotherapy Assisted by Biomaterials Tools

Chimeric antigen receptor (CAR) immune cell therapies have revolutionized oncology, particularly in hematological malignancies, yet their efficacy against solid tumors remains limited due to challenges such as dense stromal barriers and immunosuppressive microenvironments. With advancements in nanobiotechnology, researchers have developed various strategies and methods to enhance the CAR cell efficacy in solid tumor treatment. In this Review, we first outline the structure and mechanism of CAR-T (T, T cell), CAR-NK (NK, natural killer), and CAR-M (M, macrophage) cell therapies and deeply analyze the potential of these cells in the treatment of solid tumors and the challenges they face. Next, we explore how biomaterials can optimize these treatments by improving the tumor microenvironment, controlling CAR cell release, promoting cell infiltration, and enhancing efficacy. Finally, we summarize the current challenges and potential solutions, emphasize the effective combination of biomaterials and CAR cell therapy, and look forward to its future clinical application and treatment strategies. This Review provides important theoretical perspectives and practical guidance for the future development of more effective solid tumor treatment strategies.

Nanobiohybrid Oncolytic Bacteria with Optimized Intratumoral Distribution for Combined Sono-Photodynamic/Immunotherapy

"Living therapeutic carriers" present a promising avenue for cancer research, but it is still challenging to achieve uniform and durable distribution of payloads throughout the solid tumor owing to the tumor microenvironment heterogeneity. Herein, a living drug sprinkle biohybrid (YB1-HCNs) was constructed by hitching acid/enzyme-triggered detachable nanoparticles (HCNs) backpack on the surface of metabolic oligosaccharide-engineered oncolytic bacteria YB1. Along with the process of tumor penetration by bacterial hypoxia navigation, YB1-HCNs responsively and continuously release HCNs, achieving a uniform distribution of loaded agents throughout the tumor. Upon successive irradiation of laser and ultrasound (US), the HCNs can separately generate type II and type I ROS for superior sono-photodynamic therapy (SPDT), which enables HCNs to synergize with YB1 for a satisfactory therapeutic effect in both superficial normoxic and deep hypoxic regions of the tumor. After a single dose, this efficient combination realized 98.3% primary tumor inhibition rate and prolonged survival of mice for 90 days with no recurrence, further inducing a powerful immunological memory effect to completely suppress tumor rechallenge in cured mice. Such a bacterial hybridization vector enables optimization of the spatial distribution of YB1 and HCNs, providing an innovative strategy to maximize therapeutic outcomes and evoke durable antitumor immunity.

Biomaterial-Based Therapeutic Delivery of Immune Cells

Immune cell therapy (ICT) is a transformative approach used to treat a wide range of diseases including type 1 diabetes, sickle cell disease, disorders of the hematopoietic system, and certain forms of cancers. Despite excellent clinical successes, the scope of adoptively transferred immune cells is limited because of toxicities like cytokine release syndrome and immune effector cell-associated neurotoxicity in patients. Furthermore, reports suggest that such treatment can impact major organ systems including cardiac, renal, pulmonary, and hepatic systems in the long term. Additionally, adoptively transferred immune cells cannot achieve significant penetration into solid tissues, thus limiting their therapeutic potential. Recent studies suggest that biomaterial-assisted delivery of immune cells can address these challenges by reducing toxicity, improving localization, and maintaining desired phenotypes to eventually regain tissue function. In this review, recent efforts in the field of biomaterial-based immune cell delivery for the treatment of diseases, their pros and cons, and where these approaches stand in terms of clinical treatment are highlighted.

Natural polysaccharide hydrogel delivery system remodeling tumor microenvironment to promote postoperative tumor therapy

In recent years, postoperative tumor therapy with a suitable approach has been an important issue. Remodeling the tumor microenvironment and accelerating tissue repair can accelerate patients' surgical site recovery, reduce patient pain as well as prevent postoperative tumor recurrence. The shape non-adaptability, cytotoxicity, and non-degradability of some hydrogels still hinder the application of hydrogel-based drug delivery systems in postoperative recovery. Natural polysaccharides (e.g., chitosan, sodium alginate, and hyaluronic acid) are multifunctional compounds with biomimetic advantages to meet the growing demand for nontoxic, targeted therapeutic, and restorative preventive therapies. In this paper, we comprehensively and systematically investigated the synthesis methods, properties, and applications of natural polysaccharide hydrogel (NPH) delivery systems, as well as the mechanisms of remodeling the tumor microenvironment. We aim to provide insights into the design of NPH delivery systems. On this basis, future research directions for NPH delivery systems and their role in remodeling the tumor microenvironment and accelerating postoperative tumor therapy are proposed, and strategies for remodeling the tumor microenvironment using hydrogel delivery systems are discussed, as well as the latest research methods.

Advanced Polymeric Nanoparticles for Cancer Immunotherapy: Materials Engineering, Immunotherapeutic Mechanism and Clinical Translation

Cancer immunotherapy, which leverages immune system components to treat malignancies, has emerged as a cornerstone of contemporary therapeutic strategies. Yet, critical concerns about the efficacy and safety of cancer immunotherapies remain formidable. Nanotechnology, especially polymeric nanoparticles (PNPs), offers unparalleled flexibility in manipulation-from the chemical composition and physical properties to the precision control of nanoassemblies. PNPs provide an optimal platform to amplify the potency and minimize systematic toxicity in a broad spectrum of immunotherapeutic modalities. In this comprehensive review, the basics of polymer chemistry, and state-of-the-art designs of PNPs from a physicochemical standpoint for cancer immunotherapy, encompassing therapeutic cancer vaccines, in situ vaccination, adoptive T-cell therapies, tumor-infiltrating immune cell-targeted therapies, therapeutic antibodies, and cytokine therapies are delineated. Each immunotherapy necessitates distinctively tailored design strategies in polymeric nanoplatforms. The extensive applications of PNPs, and investigation of their mechanisms of action for enhanced efficacy are particularly focused on. The safety profiles of PNPs and clinical research progress are discussed. Additionally, forthcoming developments and emergent trends of polymeric nano-immunotherapeutics poised to transform cancer treatment paradigms into clinics are explored.

Harmonizing the symphony of chimeric antigen receptor T cell immunotherapy with the elegance of biomaterials

Chimeric antigen receptor T cell (CAR-T) immunotherapy has become a heated field of cancer research, demonstrating revolutionary efficacy in refractory and relapsed hematologic malignancies. However, CAR-T therapy has still encountered tough challenges, including complicated and lengthy manufacturing procedures, mediocre targeted delivery, limited therapeutic effect against solid tumors and difficulties in real-time in vivo monitoring. To overcome these limitations, various versatile biomaterials have been used in the above aspects and have improved CAR-T therapy impressively. This review mainly summarizes the latest research progress of biomaterials promoting CAR-T therapy in manufacturing, enhancing targeted delivery and tumor infiltration, and dramatic in vivo tracking to provide new insights and inspiration for clinical treatment.

Tumor-Associated Extracellular Matrix Obstacles for CAR-T Cell Therapy: Approaches to Overcoming

Chimeric antigen receptor (CAR)-T cell therapy yields good results in the treatment of various hematologic malignancies. However, the efficacy of CAR-T cell therapy against solid tumors has proven to be limited, primarily because the tumor-associated extracellular matrix (ECM) creates an intractable barrier for the cytotoxic CAR-T cells that are supposed to kill cancer cells. This review unravels the multifaceted role of the tumor-associated ECM in impeding CAR-T cell infiltration, survival, and functions within solid tumors. We analyze the situations when intratumoral ECM limits the efficacy of CAR-T cell therapy by being a purely physical barrier that complicates lymphocyte penetration/migration and also acts as an immunosuppressive factor that impairs the antitumor activities of CAR-T cells. In addition, we highlight promising approaches such as engineering CAR-T cells with improved capabilities to penetrate and migrate into/through the intratumoral ECM, combination therapies aimed at attenuating the high density and immunosuppressive potential of the intratumoral ECM, and others that enable overcoming ECM-related obstacles. A detailed overview of the data of relevant studies not only helps to better understand the interactions between CAR-T cells and the intratumoral ECM but also outlines potential ways to more effectively use CAR-T cell therapy against solid tumors.

Platelet-derived biomaterials for targeted drug delivery and tissue repair

Platelets are nucleic-free cells with a lifespan of 7-10 days in the bloodstream, playing a crucial role in various physiological processes such as hemostasis, thrombus formation, tumor development and metastasis, inflammation, and host defense. By utilizing the unique structural and functional characteristics of platelets, platelet-modified nano-drugs can evade immune recognition and clearance and facilitate prolonged circulation in vivo, which ultimately allows the nanoparticles to reach sites of disease such as thrombi, tumors, inflammation, or bacterial infections, leading to specific adhesion and significantly enhancing the efficiency of targeted drug delivery. This paper reviews the novel design and application of platelet-derived biomaterials in various diseases in recent years and comprehensively demonstrates the potential of platelet-derived biomaterials in the fields of disease therapy and biodefence, which will provide a reference for advancing the development of platelet-derived biomaterials and clinical practice.

Complexed hyaluronic acid-based nanoparticles in cancer therapy and diagnosis: Research trends by natural language processing

Hyaluronic acid (HA) is a popular surface modifier in targeted cancer delivery due to its receptor-binding abilities. However, HA alone faces limitations in lipid solubility, biocompatibility, and cell internalization, making it less effective as a standalone delivery system. This comprehensive study aimed to explore a dynamic landscape of complexation in HA-based nanoparticles in cancer therapy, examining diverse aspects from influential modifiers to emerging trends in cancer diagnostics. We discovered that certain active substances, such as 5-aminolevulinic acid, adamantane, and protamine, have been on trend in terms of their usage over the past decade. Dextran, streptavidin, and catechol emerge as intriguing conjugates for HA, coupled with nanostar, quantum dots, and nanoprobe structures for optimal drug delivery and diagnostics. Strategies like hypoxic conditioning, dual responsiveness, and pulse laser activation enhance controlled release, targeted delivery, and real-time diagnostic techniques like ultrasound imaging and X-ray computed tomography (X-ray CT). Based on our findings, conventional bibliometric tools fail to highlight relevant topics in this area, instead producing merely abstract and broad-meaning keywords. Extraction using Named Entity Recognition and topic search with Latent Dirichlet Allocation successfully revealed five representative topics with the ability to exclude irrelevant keywords. A shift in research focuses from optimizing chemical toxicity to particular targeting tactics and precise release mechanisms is evident. These findings reflect the dynamic landscape of HA-based nanoparticle research in cancer therapy, emphasizing advancements in targeted drug delivery, therapeutic efficacy, and multimodal diagnostic approaches to improve overall patient outcomes.

From Blood to Therapy: The Revolutionary Application of Platelets in Cancer-Targeted Drug Delivery

Biomimetic nanodrug delivery systems based on cell membranes have emerged as a promising approach for targeted cancer therapy due to their biocompatibility and low immunogenicity. Among them, platelet-mediated systems are particularly noteworthy for their innate tumor-homing and cancer cell interaction capabilities. These systems utilize nanoparticles shielded and directed by platelet membrane coatings for efficient drug delivery. This review highlights the role of platelets in cancer therapy, summarizes the advancements in platelet-based drug delivery systems, and discusses their integration with other cancer treatments. Additionally, it addresses the limitations and challenges of platelet-mediated drug delivery, offering insights into future developments in this innovative field.

Injectable Autocatalytic Hydrogel Triggers Pyroptosis to Stimulate Anticancer Immune Response for Preventing Postoperative Tumor Recurrence

Modulating immunosuppression while eliminating residual microscopic tumors is critical for inhibiting the postoperative recurrence of triple-negative breast cancer (TNBC). Although immunotherapy has shown potential in achieving this goal, due to multiple immunosuppression and poor immunogenicity of apoptosis, a satisfactory anti-recurrence effect still faces the challenge. Herein, an injectable hydrogel-encapsulated autocatalytic copper peroxide (CP@Gel) therapeutic platform is designed and combine it with the clinical-grade DNA methyltransferase inhibitor decitabine (DAC) to effectively inhibit TNBC growth and postoperative recurrence via pyroptosis, killing residual cancer cells that bypass apoptosis resistance while also improving immunogenicity and modulating immunosuppression to achieve an intense anti-tumor immune response. Following injection of the CP@Gel, the sustained release of CP leads to the autocatalytic generation of reactive oxygen species, resulting in caspase-3 activation, and the pre-administered DAC inhibits the methylation of Gsdme to elevate the GSDME protein levels, leading to intense pyroptosis and anti-tumor immune responses. The in vivo results show a 67% elimination of local tumor recurrence via treatment with DAC+CP@Gel, suggesting the successful integration of sustained drug release with autocatalysis and epigenetic modification. The results thus suggest great potential for pyroptosis-based and injectable hydrogel-aided strategies for preventing the postoperative recurrence of TNBC.

An Oral PROTAC Targeting HPK1 Degradation Potentiates Anti-Solid Tumor Immunity

Hematopoietic progenitor pinase1 (HPK1) knockout has been identified as an efficient route to enhance anti-tumor immune response. Here, this work develops an oral proteolysis targeting chimera (PROTAC) targeting HPK1 to efficiently and selectively degrade HPK1 to augment immunotherapeutic outcomes. In a postoperative tumor model of human cervical cancer in NSG mice, the orally-administrated PROTAC can reach tumors, down-regulate HPK1 levels in locally-administrated CAR-T cells, and promote their efficiency in inhibiting solid tumor recurrence, achieving 50% partial response (PR) and 50% complete response (CR). In addition, oral administration of PROTAC can amplify the suppression capability of the anti-PD-L1 antibody on the growth of CT26 solid tumors in BALB/c mice by promoting the infiltration of CD45-positive immune cells from 0.7% to 1.5% and CD3-positive T cells from 0.2% to 0.5% within the tumors.

Hydrogel systems for spatiotemporal controlled delivery of immunomodulators: engineering the tumor immune microenvironment for enhanced cancer immunotherapy

Tumor immunotherapy, modulating innate and adaptive immunity, has become an important therapeutic strategy. However, the tumor immune microenvironment's (TIME) complexity and heterogeneity challenge tumor immunotherapy. Hydrogel is a hydrophilic three-dimensional (3D) mesh structure with good biocompatibility and drug release control, which is widely used in drug delivery, agriculture, industry, etc. Hydrogels loaded with immune cells, cytokines, immune checkpoint inhibitors, and anti-tumor drugs can achieve targeted delivery and ultimately activate the immune response in the TIME. In this review, we will summarize the components of the TIME and their immune effects, the emerging immunomodulatory agents, the characteristics and functions of hydrogels, and how hydrogels regulate innate and adaptive immune cells in the TIME.

Engineered platelets as targeted protein degraders and application to breast cancer models

Clinical application of chimeric molecules for targeted protein degradation has been limited by unfavorable drug-like properties and biosafety concerns arising from nonspecific biodistribution after systemic administration. Here we develop a method to engineer platelets for degradation of either intracellular or extracellular proteins of interest (POIs) in vivo by covalently labeling heat shock protein 90 (HSP90) in platelets with a POI ligand. The degrader platelets (DePLTs) target wound areas and undergo activation. Depending on the tethered POI ligand and transport mechanism of the prelabeled HSP90, activated DePLTs can mediate targeted protein degradation in the target cell through the ubiquitin-proteasome machinery or the lysosome. HSP90 packaged into platelet-derived microparticles uses the ubiquitin-proteasome system to degrade intracellular POIs, whereas released free HSP90 redirects extracellular POIs to lysosomal degradation. In postsurgical breast cancer mouse models, DePLTs engineered with corresponding POI ligands effectively degrade intracellular bromodomain-containing protein 4 or extracellular programmed cell death ligand 1, thereby suppressing cancer recurrence or metastasis.

Radial Egg White Hydrogel Releasing Extracellular Vesicles for Cell Fate Guidance and Accelerated Diabetic Skin Regeneration

Topology and bioactive molecules are crucial for stimulating cellular and tissue functions. To regulate the chronic wound microenvironment, mono-assembly technology is employed to fabricate a radial egg white hydrogel loaded with lyophilized adipose tissue-extracellular vesicles (radial EWH@L-EVs). The radial architecture not only significantly modified the gene expression of functional cells, but also achieved directional and controlled release kinetics of L-EVs. Through the synergy of topographical and inherent bioactive cues, radial EWH@L-EVs effectively reduced intracellular oxidative stress and promoted the polarization of macrophages toward an anti-inflammatory phenotype during the inflammatory phase. Afterward, radial EWH@L-EVs facilitated the centripetal migration and proliferation of fibroblasts and endothelial cells as the wound transitioned to the proliferative phase. During the latter remodeling phase, radial EWH@L-EVs accelerated the regeneration of granulation tissue, angiogenesis, and collagen deposition, thereby promoting the reorganization chronic wound. Compared with the gold standard collagen scaffold, radial EWH@L-EVs actively accommodated the microenvironment via various functions throughout all stages of diabetic wound healing. This can be attributed to the orientation of topological structures and bioactive molecules, which should be considered of utmost importance in tissue engineering.

Spatiotemporal release of non-nucleotide STING agonist and AKT inhibitor from implantable 3D-printed scaffold for amplified cancer immunotherapy

Immunotherapy through the activation of the stimulator of interferon genes (STING) signaling pathway is increasingly recognized for its robust anti-tumor efficacy. However, the effectiveness of STING activation is often compromised by inadequate anti-tumor immunity and a scarcity of primed immune cells in the tumor microenvironment. Herein, we design and fabricate a co-axial 3D-printed scaffold integrating a non-nucleotide STING agonist, SR-717, and an AKT inhibitor, MK-2206, in its respective shell and core layers, to synergistically enhance STING activation, thereby suppressing tumor recurrence and growth. SR-717 initiates the STING activation to enhance the phosphorylation of the factors along the STING pathway, while MK-2206 concurrently inhibits the AKT phosphorylation to facilitate the TBK1 phosphorylation of the STING pathway. The sequential and sustained release of SR-717 and MK-2206 from the scaffold results in a synergistic STING activation, demonstrating substantial anti-tumor efficacy across multiple tumor models. Furthermore, the scaffold promotes the recruitment and enrichment of activated dendritic cells and M1 macrophages, subsequently stimulating anti-tumor T cell activity, thereby amplifying the immunotherapeutic effect. This precise and synergistic activation of STING by the scaffold offers promising potential in tumor immunotherapy.

Nanoengineered mitochondria enable ocular mitochondrial disease therapy via the replacement of dysfunctional mitochondria

Leber's hereditary optic neuropathy (LHON) is an ocular mitochondrial disease that involves the impairment of mitochondrial complex I, which is an important contributor to blindness among young adults across the globe. However, the disorder has no available cures, since the approved drug idebenone for LHON in Europe relies on bypassing complex I defects rather than fixing them. Herein, PARKIN mRNA-loaded nanoparticle (mNP)-engineered mitochondria (mNP-Mito) were designed to replace dysfunctional mitochondria with the delivery of exogenous mitochondria, normalizing the function of complex I for treating LHON. The mNP-Mito facilitated the supplementation of healthy mitochondria containing functional complex I via mitochondrial transfer, along with the elimination of dysfunctional mitochondria with impaired complex I via an enhanced PARKIN-mediated mitophagy process. In a mouse model induced with a complex I inhibitor (rotenone, Rot), mNP-Mito enhanced the presence of healthy mitochondria and exhibited a sharp increase in complex I activity (76.5%) compared to the group exposed to Rot damage (29.5%), which greatly promoted the restoration of ATP generation and mitigation of ocular mitochondrial disease-related phenotypes. This study highlights the significance of nanoengineered mitochondria as a promising and feasible tool for the replacement of dysfunctional mitochondria and the repair of mitochondrial function in mitochondrial disease therapies.

Protecting Against Postsurgery Oral Cancer Recurrence with an Implantable Hydrogel Vaccine for In Situ Photoimmunotherapy

Oral squamous cell carcinoma (OSCC) often recurs aggressively and metastasizes despite surgery and adjuvant therapy, driven by postoperative residual cancer cells near the primary tumor site. An implantable in situ vaccine hydrogel was designed to target residual OSCC cells post-tumor removal. This hydrogel serves as a reservoir for the sustained localized release of δ-aminolevulinic acid (δ-ALA), enhancing protoporphyrin IX-mediated photodynamic therapy (PDT), and a polydopamine-hyaluronic acid composite for photothermal therapy (PTT). Additionally, immune adjuvants, including anti-CD47 antibodies (aCD47) and CaCO3 nanoparticles, are directly released into the resected tumor bed. This approach induces apoptosis of residual OSCC cells through sequential near-infrared irradiation, promoting calcium interference therapy (CIT). The hydrogel further stimulates immunogenic cell death (ICD), facilitating the polarization of tumor-associated macrophages from the M2 to the M1 phenotype. This facilitates phagocytosis, dendritic cell activation, robust antigen presentation, and cytotoxic T lymphocyte-mediated cytotoxicity. In murine OSCC models, the in situ vaccine effectively prevents local recurrence, inhibits orthotopic OSCC growth and pulmonary metastases, and provides long-term protective immunity against tumor rechalle nge. These findings support postoperative in situ vaccination with a biocompatible hydrogel implant as a promising strategy to minimize residual tumor burden and reduce recurrence risk after OSCC resection.

Advances in cancer diagnosis and therapy by alginate-based multifunctional hydrogels: A review

The field of oncology has been changed by the application of hydrogels. These 3D polymeric networks have demonstrated significant promise in the treatment of cancer and can boost the efficacy of conventional therapeutics including chemotherapy and immunotherapy. Noteworthy, the development of biocompatible and effective hydrogels has been of interest. In this case, alginate as a biopolymer and carbohydrate polymer has been used to modify or synthesis multifunctional nanoparticles for the treatment of human diseases, especially cancer. Therefore, highlighting the function of alginate in the development of hydrogels in cancer therapy can provide new insights for improving outcome and survival rate of patients. Alginate hydrogels improve the specific and selective delivery of cargo and therefore, they reduce the systemic toxicity of drugs, while they enhance anti-cancer activity. Alginate hydrogels protect the genes against degradation by enzymes and increase blood circulation time. The alginate hydrogels can respond to the specific stimuli in the tumor microenvironment including pH, redox and light to improve the site-specific release of cargo. The nanoparticles can be incorporated in the structure of alginate hydrogels to augment their anti-cancer activity. In addition, alginate hydrogels can accelerate immunotherapy and phototherapy through delivery of immunomodulators and photosensitizers, respectively.

Emerging Strategies for Local Delivery of Immune Checkpoint Inhibitors to Potentiate Cancer Immunotherapy: Current Status and Future Prospects

Cancer constitutes a significant threat to patients' lives worldwide. Immunotherapy, particularly immune checkpoint inhibitors (ICIs) that boost antitumor immunity by targeting immune checkpoint components, has emerged as a promising strategy for its treatment in recent years. However, the objective response rates of the ICIs are unsatisfactory. As the primary route, systemic administration of ICIs is often accompanied by immune-related adverse events. Local delivery of ICIs serves as a potential therapeutic strategy that can improve the efficacy while simultaneously reducing side effects through precise drug release at the tumor site. Initial validation of direct local application of ICIs for tumors in clinical trials has indicated reduced side effects and improved efficacy, while low bioavailability remains a challenge. Furthermore, research on various carriers, including nanoparticles, microneedles, hydrogels, combined platforms, and implantable devices for local release of ICIs has exhibited applying potential in treating murine tumors, among which combined platforms such as combined hydrogel system hold the highest promise due to their encompassment of the advantages of multiple carriers. These carriers, by incorporating ICIs and other therapeutics, could manage cancers more potently, which needs to be confirmed in clinical trials after the refinement of their biocompatibility. This review summarizes the latest research advancements regarding local administration of ICIs, with a particular focus on the carriers for local delivery as well as the combination therapies, thus providing novel insights and research guidance for scholars to enhance the efficacy of locally delivered ICIs on managing multiple cancers in the future.

Optimizing CAR-T cell therapy for solid tumors: current challenges and potential strategies

Chimeric antigen receptor (CAR)-T cell therapy demonstrates substantial efficacy in various hematological malignancies. However, its application in solid tumors is still limited. Clinical studies report suboptimal outcomes such as reduced cytotoxicity of CAR-T cells and tumor evasion, underscoring the need to address the challenges of sliding cytotoxicity in CAR-T cells. Despite improvements from fourth and next-generation CAR-T cells, new challenges include systemic toxicity from continuously secreted proteins, low productivity, and elevated costs. Recent research targets genetic modifications to boost killing potential, metabolic interventions to hinder tumor progression, and diverse combination strategies to enhance CAR-T cell therapy. Efforts to reduce the duration and cost of CAR-T cell therapy include developing allogenic and in-vivo approaches, promising significant future advancements. Concurrently, innovative technologies and platforms enhance the potential of CAR-T cell therapy to overcome limitations in treating solid tumors. This review explores strategies to optimize CAR-T cell therapies for solid tumors, focusing on enhancing cytotoxicity and overcoming application restrictions. We summarize recent advances in T cell subset selection, CAR-T structural modifications, infiltration enhancement, genetic and metabolic interventions, production optimization, and the integration of novel technologies, presenting therapeutic approaches that could improve CAR-T cell therapy's efficacy and applicability in solid tumors.

Cell-drug conjugates

By combining living cells with therapeutics, cell-drug conjugates can potentiate the functions of both components, particularly for applications in drug delivery and therapy. The conjugates can be designed to persist in the bloodstream, undergo chemotaxis, evade surveillance by the immune system, proliferate, or maintain or transform their cellular phenotypes. In this Review, we discuss strategies for the design of cell-drug conjugates with specific functions, the techniques for their preparation, and their applications in the treatment of cancers, autoimmune diseases and other pathologies. We also discuss the translational challenges and opportunities of this class of drug-delivery systems and therapeutics.

Intelligent Hydrogel-Assisted Hepatocellular Carcinoma Therapy

Given the high malignancy of liver cancer and the liver's unique role in immune and metabolic regulation, current treatments have limited efficacy, resulting in a poor prognosis. Hydrogels, soft 3-dimensional network materials comprising numerous hydrophilic monomers, have considerable potential as intelligent drug delivery systems for liver cancer treatment. The advantages of hydrogels include their versatile delivery modalities, precision targeting, intelligent stimulus response, controlled drug release, high drug loading capacity, excellent slow-release capabilities, and substantial potential as carriers of bioactive molecules. This review presents an in-depth examination of hydrogel-assisted advanced therapies for hepatocellular carcinoma, encompassing small-molecule drug therapy, immunotherapy, gene therapy, and the utilization of other biologics. Furthermore, it examines the integration of hydrogels with conventional liver cancer therapies, including radiation, interventional therapy, and ultrasound. This review provides a comprehensive overview of the numerous advantages of hydrogels and their potential to enhance therapeutic efficacy, targeting, and drug delivery safety. In conclusion, this review addresses the clinical implementation of hydrogels in liver cancer therapy and future challenges and design principles for hydrogel-based systems, and proposes novel research directions and strategies.

Water-Enhancing Gels Exhibiting Heat-Activated Formation of Silica Aerogels for Protection of Critical Infrastructure During Catastrophic Wildfire

A promising strategy to address the pressing challenges with wildfire, particularly in the wildland-urban interface (WUI), involves developing new approaches for preventing and controlling wildfire within wildlands. Among sprayable fire-retardant materials, water-enhancing gels have emerged as exceptionally effective for protecting civil infrastructure. They possess favorable wetting and viscoelastic properties that reduce the likelihood of ignition, maintaining strong adherence to a wide array of surfaces after application. Although current water-enhancing hydrogels effectively maintain surface wetness by creating a barricade, they rapidly desiccate and lose efficacy under high heat and wind typical of wildfire conditions. To address this limitation, unique biomimetic hydrogel materials from sustainable cellulosic polymers crosslinked by colloidal silica particles are developed that exhibit ideal viscoelastic properties and facile manufacturing. Under heat activation, the hydrogel transitions into a highly porous and thermally insulative silica aerogel coating in situ, providing a robust protective layer against ignition of substrates, even when the hydrogel fire suppressant becomes completely desiccated. By confirming the mechanical properties, substrate adherence, and enhanced substrate protection against fire, these heat-activatable biomimetic hydrogels emerge as promising candidates for next-generation water-enhancing fire suppressants. These advancements have the potential to dramatically improve the ability to protect homes and critical infrastructure during wildfire.

Bioresponsive Immunotherapeutic Materials

The human immune system is an interaction network of biological processes, and its dysfunction is closely associated with a wide array of diseases, such as cancer, infectious diseases, tissue damage, and autoimmune diseases. Manipulation of the immune response network in a desired and controlled fashion has been regarded as a promising strategy for maximizing immunotherapeutic efficacy and minimizing side effects. Integration of "smart" bioresponsive materials with immunoactive agents including small molecules, biomacromolecules, and cells can achieve on-demand release of agents at targeted sites to reduce overdose-related toxicity and alleviate off-target effects. This review highlights the design principles of bioresponsive immunotherapeutic materials and discusses the critical roles of controlled release of immunoactive agents from bioresponsive materials in recruiting, housing, and manipulating immune cells for evoking desired immune responses. Challenges and future directions from the perspective of clinical translation are also discussed.

Delivery Systems Developed for Treatment Combinations to Improve Adoptive Cell Therapy

Adoptive cell therapy (ACT) has shown great success in the clinic for treating hematologic malignancies. However, solid tumor treatment with ACT monotherapy is still challenging, owing to insufficient expansion and rapid exhaustion of adoptive cells, tumor antigen downregulation/loss, and dense tumor extracellular matrix. Delivery strategies for combination cell therapy have great potential to overcome these hurdles. The delivery of vaccines, immune checkpoint inhibitors, cytokines, chemotherapeutics, and photothermal reagents in combination with adoptive cells, have been shown to improve the expansion/activation, decrease exhaustion, and promote the penetration of adoptive cells in solid tumors. Moreover, the delivery of nucleic acids to engineer immune cells directly in vivo holds promise to overcome many of the hurdles associated with the complex ex vivo cell engineering strategies. Here, these research advance, as well as the opportunities and challenges for integrating delivery technologies into cell therapy s are discussed, and the outlook for these emerging areas are criticlly analyzed.

Prospects of Synergy: Local Interventions and CAR T Cell Therapy in Solid Tumors

Chimeric antigen receptor T cell therapy has been established in the treatment of various B cell malignancies. However, translating this therapeutic effect to treat solid tumors has been challenging because of their inter-tumoral as well as intratumoral heterogeneity and immunosuppressive microenvironment. Local interventions, such as surgery, radiotherapy, local ablation, and locoregional drug delivery, can enhance chimeric antigen receptor T cell therapy in solid tumors by improving tumor infiltration and reducing systemic toxicities. Additionally, ablation and radiotherapy have proven to (re-)activate systemic immune responses via abscopal effects and reprogram the tumor microenvironment on a physical, cellular, and chemical level. This review highlights the potential synergy of the combined approaches to overcome barriers of chimeric antigen receptor T cell therapy and summarizes recent studies that may pave the way for new treatment regimens.

Current status and future perspectives of platelet-derived extracellular vesicles in cancer diagnosis and treatment

Platelets are a significant component of the cell population in the tumour microenvironment (TME). Platelets influence other immune cells and perform cross-talk with tumour cells, playing an important role in tumour development. Extracellular vesicles (EVs) are small membrane vesicles released from the cells into the TME. They can transfer biological information, including proteins, nucleic acids, and metabolites, from secretory cells to target receptor cells. This process affects the progression of various human diseases, particularly cancer. In recent years, several studies have demonstrated that platelet-derived extracellular vesicles (PEVs) can help regulate the malignant biological behaviours of tumours, including malignant proliferation, resistance to cell death, invasion and metastasis, metabolic reprogramming, immunity, and angiogenesis. Consequently, PEVs have been identified as key regulators of tumour progression. Therefore, targeting PEVs is a potential strategy for tumour treatment. Furthermore, the extensive use of nanomaterials in medical research has indicated that engineered PEVs are ideal delivery systems for therapeutic drugs. Recent studies have demonstrated that PEV engineering technologies play a pivotal role in the treatment of tumours by combining photothermal therapy, immunotherapy, and chemotherapy. In addition, aberrant changes in PEVs are closely associated with the clinicopathological features of patients with tumours, which may serve as liquid biopsy markers for early diagnosis, monitoring disease progression, and the prognostic assessment of patients with tumours. A comprehensive investigation into the role and potential mechanisms of PEVs in tumourigenesis may provide novel diagnostic biomarkers and potential therapeutic strategies for treating human tumours.

Theoretical basis, state and challenges of living cell-based drug delivery systems

The therapeutic efficacy of drugs is determined, to a certain extent, by the efficiency of drug delivery. The low efficiency of drug delivery systems (DDSs) is frequently associated with serious toxic side effects and can even prove fatal in certain cases. With the rapid development of technology, drug delivery has evolved from using traditional frameworks to using nano DDSs (NDDSs), endogenous biomaterials DDSs (EBDDSs), and living cell DDSs (LCDDSs). LCDDSs are receiving widespread attention from researchers at present owing to the unique advantages of living cells in targeted drug delivery, including their excellent biocompatibility properties, low immunogenicity, unique biological properties and functions, and role in the treatment of diseases. However, the theoretical basis and techniques involved in the application of LCDDSs have not been extensively summarized to date. Therefore, this review comprehensively summarizes the properties and applications of living cells, elaborates the various drug loading approaches and controlled drug release, and discusses the results of clinical trials. The review also discusses the current shortcomings and prospects for the future development of LCDDSs, which will serve as highly valuable insights for the development and clinical transformation of LCDDSs in the future.

Biomaterial-Based Sustained-Release Drug Formulations for Localized Cancer Immunotherapy

Cancer immunotherapy has revolutionized clinical cancer treatments by taking advantage of the immune system to selectively and effectively target and kill cancer cells. However, clinical cancer immunotherapy treatments often have limited efficacy and/or present severe adverse effects associated primarily with their systemic administration. Localized immunotherapy has emerged to overcome these limitations by directly targeting accessible tumors via local administration, reducing potential systemic drug distribution that hampers drug efficacy and safety. Sustained-release formulations can prolong drug activity at target sites, which maximizes the benefits of localized immunotherapy to increase the therapeutic window using smaller dosages than those used for systemic injection, avoiding complications of frequent dosing. The performance of sustained-release formulations for localized cancer immunotherapy has been validated preclinically using various implantable and injectable scaffold platforms. This review introduces the sustained-release formulations developed for localized cancer immunotherapy and highlights their biomaterial-based platforms for representative classes, including inorganic scaffolds, natural hydrogels, synthetic hydrogels, and microneedle patches. The design rationale and other considerations are summarized for further development of biomaterials for the construction of optimal sustained-release formulations.

Strategies to enhance the therapeutic efficacy of anti-PD-1 antibody, anti-PD-L1 antibody and anti-CTLA-4 antibody in cancer therapy

Although immune checkpoint inhibitors (anti-PD-1 antibody, anti-PD-L1 antibody, and anti-CTLA-4 antibody) have displayed considerable success in the treatment of malignant tumors, the therapeutic effect is still unsatisfactory for a portion of patients. Therefore, it is imperative to develop strategies to enhance the effect of these ICIs. Increasing evidence strongly suggests that the key to this issue is to transform the tumor immune microenvironment from a state of no or low immune infiltration to a state of high immune infiltration and enhance the tumor cell-killing effect of T cells. Therefore, some combination strategies have been proposed and this review appraise a summary of 39 strategies aiming at enhancing the effectiveness of ICIs, which comprise combining 10 clinical approaches and 29 foundational research strategies. Moreover, this review improves the comprehensive understanding of combination therapy with ICIs and inspires novel ideas for tumor immunotherapy.

Anti-angiogenesis and anti-immunosuppression gene therapy through targeting COUP-TFII in an in situ glioblastoma mouse model

Glioblastoma (GBM) is the most common and aggressive primary brain cancer; angiogenesis and immunosuppression exacerbate GBM progression. COUP-TFII demonstrates pro-angiogenesis activity; however, its role in glioma progression remains unclear. This study revealed that COUP-TFII promotes angiogenesis in gliomas by inducing transdifferentiation of glioma cells into endothelial-like cells. Mechanistic investigation suggested that COUP-TFII as a transcription factor exerts its function via binding to the promoter of TXNIP. Interestingly, COUP-TFII knockdown attenuated tumorigenesis and tumor progression in an immunocompetent mouse model but promoted tumor progression in an immuno-deficient mouse model. As an explanation, repression of COUP-TFII induces cellular senescence and activates immune surveillance in glioma cells in vitro and in vivo. In addition, we used heparin-polyethyleneimine (HPEI) nanoparticles to deliver COUP-TFII shRNA, which regulated tumor angiogenesis and immunosuppression in an in situ GBM mouse model. This study provides a novel strategy and potential therapeutic targets to treat GBM.

Recent Advancements in Biomaterials for Chimeric Antigen Receptor T Cell Immunotherapy

Cellular immunotherapy is an innovative cancer treatment method that utilizes the patient's own immune system to combat tumor cells effectively. Currently, the mainstream therapeutic approaches include chimeric antigen receptor T cell (CAR-T) therapy, T cell receptor gene-modified T cell therapy and chimeric antigen receptor natural killer-cell therapy with CAR-T therapy mostly advanced. Nonetheless, the conventional manufacturing process of this therapy has shortcomings in each step that call for improvement. Marked efforts have been invested for its enhancement while notable progresses achieved in the realm of biomaterials application. With CAR-T therapy as a prime example, the aim of this review is to comprehensively discuss the various biomaterials used in cell immunotherapy, their roles in regulating immune cells, and their potential for breakthroughs in cancer treatment from gene transduction to efficacy enhancement. This article additionally addressed widely adopted animal models for efficacy evaluating.

Synergistic Effects of Shed-Derived Exosomes, Cu2+, and an Injectable Hyaluronic Acid Hydrogel on Antibacterial, Anti-inflammatory, and Osteogenic Activity for Periodontal Bone Regeneration

The primary pathology of periodontitis involves the gradual deterioration of periodontal tissues resulting from the inflammatory reaction triggered by bacterial infection. In this study, a novel drug for periodontal pocket injection, known as the Shed-Cu-HA hydrogel, was developed by incorporating copper ions (Cu2+) and Shed-derived exosomes (Shed-exo) inside the hyaluronic acid (HA) hydrogel. Suitable concentrations of Cu2+ and Shed-exo released from Shed-Cu-HA enhanced cell viability and cell proliferation of human periodontal ligament stem cells. Additionally, the Shed-Cu-HA demonstrated remarkable antibacterial effects against the key periodontal pathogen (Aa) owing to the synergistic effect of Cu2+ and HA. Furthermore, the material effectively suppressed macrophage inflammatory response via the IL-6/JAK2/STAT3 pathway. Moreover, the Shed-Cu-HA, combining the inflammation-regulating properties of HA with the synergistic osteogenic activity of Shed-exo and Cu2+, effectively upregulated the expression of genes and proteins associated with osteogenic differentiation. The experimental findings from a mouse periodontitis model demonstrated that the administration of Shed-Cu-HA effectively reduced the extent of inflammatory cell infiltration and bacterial infections in gingival tissues and facilitated the regeneration of periodontal bone tissues and collagen after 2 and 4 weeks of injection. Consequently, it holds significant prospects for future applications in periodontitis treatment.

Implantable CAR T cell factories enhance solid tumor treatment

Chimeric Antigen Receptor (CAR) T cell therapy has produced revolutionary success in hematological cancers such as leukemia and lymphoma. Nonetheless, its translation to solid tumors faces challenges due to manufacturing complexities, short-lived in vivo persistence, and transient therapeutic impact. We introduce 'Drydux' - an innovative macroporous biomaterial scaffold designed for rapid, efficient in-situ generation of tumor-specific CAR T cells. Drydux expedites CAR T cell preparation with a mere three-day turnaround from patient blood collection, presenting a cost-effective, streamlined alternative to conventional methodologies. Notably, Drydux-enabled CAR T cells provide prolonged in vivo release, functionality, and enhanced persistence exceeding 150 days, with cells transitioning to memory phenotypes. Unlike conventional CAR T cell therapy, which offered only temporary tumor control, equivalent Drydux cell doses induced lasting tumor remission in various animal tumor models, including systemic lymphoma, peritoneal ovarian cancer, metastatic lung cancer, and orthotopic pancreatic cancer. Drydux's approach holds promise in revolutionizing solid tumor CAR T cell therapy by delivering durable, rapid, and cost-effective treatments and broadening patient accessibility to this groundbreaking therapy.

Breaking the Tumor Chronic Inflammation Balance with a Programmable Release and Multi-Stimulation Engineering Scaffold for Potent Immunotherapy

Tumor-associated chronic inflammation severely restricts the efficacy of immunotherapy in cold tumors. Here, a programmable release hydrogel-based engineering scaffold with multi-stimulation and reactive oxygen species (ROS)-response (PHOENIX) is demonstrated to break the chronic inflammatory balance in cold tumors to induce potent immunity. PHOENIX can undergo programmable release of resiquimod and anti-OX40 under ROS. Resiquimod is first released, leading to antigen-presenting cell maturation and the transformation of myeloid-derived suppressor cells and M2 macrophages into an antitumor immune phenotype. Subsequently, anti-OX40 is transported into the tumor microenvironment, leading to effector T-cell activation and inhibition of Treg function. PHOENIX consequently breaks the chronic inflammation in the tumor microenvironment and leads to a potent immune response. In mice bearing subcutaneous triple-negative breast cancer and metastasis models, PHOENIX effectively inhibited 80% and 60% of tumor growth, respectively. Moreover, PHOENIX protected 100% of the mice against TNBC tumor rechallenge by electing a robust long-term antigen-specific immune response. An excellent inhibition and prolonged survival in PHOENIX-treated mice with colorectal cancer and melanoma is also observed. This work presents a potent therapeutic scaffold to improve immunotherapy efficiency, representing a generalizable and facile regimen for cold tumors.

Immunotherapies for locally aggressive cancers

Improving surgical resection outcomes for locally aggressive tumors is key to inducing durable locoregional disease control and preventing progression to metastatic disease. Macroscopically complete resection of the tumor is the standard of care for many cancers, including breast, ovarian, lung, sarcoma, and mesothelioma. Advancements in cancer diagnostics are increasing the number of surgically eligible cases through early detection. Thus, a unique opportunity arises to improve patient outcomes with decreased recurrence rates via intraoperative delivery treatments using local drug delivery strategies after the tumor has been resected. Of the current systemic treatments (e.g., chemotherapy, targeted therapies, and immunotherapies), immunotherapies are the latest approach to offer significant benefits. Intraoperative strategies benefit from direct access to the tumor microenvironment which improves drug uptake to the tumor and simultaneously minimizes the risk of drug entering healthy tissues thereby resulting in fewer or less toxic adverse events. We review the current state of immunotherapy development and discuss the opportunities that intraoperative treatment provides. We conclude by summarizing progress in current research, identifying areas for exploration, and discussing future prospects in sustained remission.

Harnessing the potential of hydrogels for advanced therapeutic applications: current achievements and future directions

The applications of hydrogels have expanded significantly due to their versatile, highly tunable properties and breakthroughs in biomaterial technologies. In this review, we cover the major achievements and the potential of hydrogels in therapeutic applications, focusing primarily on two areas: emerging cell-based therapies and promising non-cell therapeutic modalities. Within the context of cell therapy, we discuss the capacity of hydrogels to overcome the existing translational challenges faced by mainstream cell therapy paradigms, provide a detailed discussion on the advantages and principal design considerations of hydrogels for boosting the efficacy of cell therapy, as well as list specific examples of their applications in different disease scenarios. We then explore the potential of hydrogels in drug delivery, physical intervention therapies, and other non-cell therapeutic areas (e.g., bioadhesives, artificial tissues, and biosensors), emphasizing their utility beyond mere delivery vehicles. Additionally, we complement our discussion on the latest progress and challenges in the clinical application of hydrogels and outline future research directions, particularly in terms of integration with advanced biomanufacturing technologies. This review aims to present a comprehensive view and critical insights into the design and selection of hydrogels for both cell therapy and non-cell therapies, tailored to meet the therapeutic requirements of diverse diseases and situations.