A Hybrid Eukaryotic-Prokaryotic Nanoplatform with Photothermal Modality for Enhanced Antitumor Vaccination

Tumor targeting peptide TMTP1 modified Antigen capture Nano-vaccine combined with chemotherapy and PD-L1 blockade effectively inhibits growth of ovarian cancer

The mortality of ovarian cancer (OC) has long been the highest among gynecological malignancies. Although OC is considered to be an immunogenic tumor, the effect of immunotherapy is not satisfactory. The immunosuppressive microenvironment is one reason for this, and the absence of recognized effective antigens for vaccines is another. Chemotherapy, as one of the most commonly used treatment for OC, can produce chemotherapy-associated antigens (CAAs) during treatment and show the effect of in situ vaccine. Herein, we designed an antigen capture nano-vaccine NP-TP1@M-M with tumor targeting peptide TMTP1 and dendritic cell (DC) receptor mannose assembled on the surface and adjuvant monophosphoryl lipid A (MPLA) encapsulated in the core of poly (D, L-lactide-co-glycolide) (PLGA) nanoparticles. PLGA itself possessed the ability of antigen capture. TMTP1 was a tumor-homing peptide screened by our research team, which held extensive and excellent tumor targeting ability. After these modifications, NP-TP1@M-M could capture and enrich more tumor-specific antigens after chemotherapy, stimulate DC maturation, activate the adaptive immunity and combined with immune checkpoint blockade to maximize the release of the body's immune potential, providing an eutherapeutic strategy for the treatment of OC.

Enhancing in situ cancer vaccines using delivery technologies

In situ cancer vaccination refers to any approach that exploits tumour antigens available at a tumour site to induce tumour-specific adaptive immune responses. These approaches hold great promise for the treatment of many solid tumours, with numerous candidate drugs under preclinical or clinical evaluation and several products already approved. However, there are challenges in the development of effective in situ cancer vaccines. For example, inadequate release of tumour antigens from tumour cells limits antigen uptake by immune cells; insufficient antigen processing by antigen-presenting cells restricts the generation of antigen-specific T cell responses; and the suppressive immune microenvironment of the tumour leads to exhaustion and death of effector cells. Rationally designed delivery technologies such as lipid nanoparticles, hydrogels, scaffolds and polymeric nanoparticles are uniquely suited to overcome these challenges through the targeted delivery of therapeutics to tumour cells, immune cells or the extracellular matrix. Here, we discuss delivery technologies that have the potential to reduce various clinical barriers for in situ cancer vaccines. We also provide our perspective on this emerging field that lies at the interface of cancer vaccine biology and delivery technologies.

GSH-responsive bithiophene Aza-BODIPY@HMON nanoplatform for achieving triple-synergistic photoimmunotherapy

Photoimmunotherapy represents an innovative approach to enhancing the efficiency of immunotherapy in cancer treatment. This approach involves the fusion of immunotherapy and phototherapy (encompassing techniques like photodynamic therapy (PDT) and photothermal therapy (PTT)). Boron-dipyrromethene (BODIPY) has the potential to trigger immunotherapy owing to its excellent PD and PT efficiency. However, the improvements in water solubility, bioavailability, PD/PT combined efficiency, and tumor tissue targeting of BODIPY require introduction of suitable carriers for potential practical application. Herein, a disulfide bond-based hollow mesoporous organosilica (HMON) with excellent biocompatibility and GSH-responsive degradation properties was used as a carrier to load a bithiophene Aza-BODIPY dye (B5), constructing a sample chemotherapy reagent-free B5@HMON nanoplatform achieving triple-synergistic photoimmunotherapy. HMON, involving disulfide bond, is utilized to improve water solubility, tumor tissue targeting, and PD efficiency by depleting GSH and enhancing host-guest interaction between B5 and HMO. The study reveals that HMON's large specific surface area and porous properties significantly enhance the light collection and oxygen adsorption capacity. The HMON's rich mesoporous structure and internal cavity achieved a loading rate of B5 at 11 %. It was found that the triple-synergistic nanoplatform triggered a stronger anti-tumor immune response, including tumor invasion, cytokine production, calreticulin translocation, and dendritic cell maturation, eliciting specific tumor-specific immunological responses in vivo and in vitro. The BALB/c mouse model with 4T1 tumors was used to assess tumor suppression efficiency in vivo, showing that almost all tumors in the B5@HMON group disappeared after 14 days. Such a simple chemotherapy reagent-free B5@HMON nanoplatform achieved triple-synergistic photoimmunotherapy.

Bacteria extracellular vesicle as nanopharmaceuticals for versatile biomedical potential

Bacteria extracellular vesicles (BEVs), characterized as the lipid bilayer membrane-surrounded nanoparticles filled with molecular cargo from parent cells, play fundamental roles in the bacteria growth and pathogenesis, as well as facilitating essential interaction between bacteria and host systems. Notably, benefiting from their unique biological functions, BEVs hold great promise as novel nanopharmaceuticals for diverse biomedical potential, attracting significant interest from both industry and academia. Typically, BEVs are evaluated as promising drug delivery platforms, on account of their intrinsic cell-targeting capability, ease of versatile cargo engineering, and capability to penetrate physiological barriers. Moreover, attributing to considerable intrinsic immunogenicity, BEVs are able to interact with the host immune system to boost immunotherapy as the novel nanovaccine against a wide range of diseases. Towards these significant directions, in this review, we elucidate the nature of BEVs and their role in activating host immune response for a better understanding of BEV-based nanopharmaceuticals' development. Additionally, we also systematically summarize recent advances in BEVs for achieving the target delivery of genetic material, therapeutic agents, and functional materials. Furthermore, vaccination strategies using BEVs are carefully covered, illustrating their flexible therapeutic potential in combating bacterial infections, viral infections, and cancer. Finally, the current hurdles and further outlook of these BEV-based nanopharmaceuticals will also be provided.

Recent progress in biomimetic nanomedicines based on versatile targeting strategy for atherosclerosis therapy

Atherosclerosis (AS) is considered to be one of the major causes of cardiovascular disease. Its pathological microenvironment is characterised by increased production of reactive oxygen species, lipid oxides, and excessive inflammatory factors, which accumulate at the monolayer endothelial cells in the vascular wall to form AS plaques. Therefore, intervention in the pathological microenvironment would be beneficial in delaying AS. Researchers have designed biomimetic nanomedicines with excellent biocompatibility and the ability to avoid being cleared by the immune system through different therapeutic strategies to achieve better therapeutic effects for the characteristics of AS. Biomimetic nanomedicines can further enhance delivery efficiency and improve treatment efficacy due to their good biocompatibility and ability to evade clearance by the immune system. Biomimetic nanomedicines based on therapeutic strategies such as neutralising inflammatory factors, ROS scavengers, lipid clearance and integration of diagnosis and treatment are versatile approaches for effective treatment of AS. The review firstly summarises the targeting therapeutic strategy of biomimetic nanomedicine for AS in recent 5 years. Biomimetic nanomedicines using cell membranes, proteins, and extracellular vesicles as carriers have been developed for AS.

Hybrid Cell Membrane-Based Nanoplatforms for Enhanced Immunotherapy against Cancer and Infectious Diseases

Immunotherapy based on nanoplatforms is a promising approach to treat cancer and infectious diseases, and it has achieved considerable progress in clinical practices. Cell membrane-based nanoplatforms endow nanoparticles with versatile characteristics, such as half-life extension, targeting ability, and immune-system regulation. However, monotypic cell membrane usually fails to provoke strong immune response for immunotherapy while maintaining good biosafety. The integration of different cell-membrane types provides a promising approach to construct multifunctional nanoplatforms for improved immunotherapeutic efficacy by enhancing immunogenicity or targeting function, evading immune clearance, or combining with other therapeutic modalities. In this review, the design principles, preparation strategies, and applications of hybrid cell membrane-based nanoplatforms for cancer and infection immunotherapy are first discussed. Furthermore, the challenges and prospects for the potential clinical translation of hybrid cell membrane-based nanoplatforms are discussed.

The role of extracellular vesicles in immune cell exhaustion and resistance to immunotherapy

INTRODUCTION

Extracellular vesicles (EVs) are membrane-bound nanoparticles for intercellular communication. Subtypes of EVs, namely exosomes and microvesicles transfer diverse, bioactive cargo to their target cells and eventually interfere with immune responses. Despite being a promising approach, cancer immunotherapy currently faces several challenges including immune resistance. EVs secreted from various sources in the tumor microenvironment provoke immune cell exhaustion and lower the efficacy of immunological treatments, such as CAR T cells and immune checkpoint inhibitors.

AREAS COVERED

This article goes through the mechanisms of action of various types of EVs in inhibiting immune response and immunotherapies, and provides a comprehensive review of EV-based treatments.

EXPERT OPINION

By making use of the distinctive features of EVs, natural or modified EVs are innovatively utilized as novel cancer therapeutics. They are occasionally coupled with currently established treatments to overcome their inadequacies. Investigating the properties and interactions of EVs and EV-based treatments is crucial for determining future steps in cancer therapeutics.

Engineering Versatile Bacteria-Derived Outer Membrane Vesicles: An Adaptable Platform for Advancing Cancer Immunotherapy

In recent years, cancer immunotherapy has undergone a transformative shift toward personalized and targeted therapeutic strategies. Bacteria-derived outer membrane vesicles (OMVs) have emerged as a promising and adaptable platform for cancer immunotherapy due to their unique properties, including natural immunogenicity and the ability to be engineered for specific therapeutic purposes. In this review, a comprehensive overview is provided of state-of-the-art techniques and methodologies employed in the engineering of versatile OMVs for cancer immunotherapy. Beginning by exploring the biogenesis and composition of OMVs, unveiling their intrinsic immunogenic properties for therapeutic appeal. Subsequently, innovative approaches employed to engineer OMVs are delved into, ranging from the genetic engineering of parent bacteria to the incorporation of functional molecules. The importance of rational design strategies is highlighted to enhance the immunogenicity and specificity of OMVs, allowing tailoring for diverse cancer types. Furthermore, insights into clinical studies and potential challenges utilizing OMVs as cancer vaccines or adjuvants are also provided, offering a comprehensive assessment of the current landscape and future prospects. Overall, this review provides valuable insights for researchers involved in the rapidly evolving field of cancer immunotherapy, offering a roadmap for harnessing the full potential of OMVs as a versatile and adaptable platform for cancer treatment.

Harnessing Bacterial Membrane Components for Tumor Vaccines: Strategies and Perspectives

Tumor vaccines stand at the vanguard of tumor immunotherapy, demonstrating significant potential and promise in recent years. While tumor vaccines have achieved breakthroughs in the treatment of cancer, they still encounter numerous challenges, including improving the immunogenicity of vaccines and expanding the scope of vaccine application. As natural immune activators, bacterial components offer inherent advantages in tumor vaccines. Bacterial membrane components, with their safer profile, easy extraction, purification, and engineering, along with their diverse array of immune components, activate the immune system and improve tumor vaccine efficacy. This review systematically summarizes the mechanism of action and therapeutic effects of bacterial membranes and its derivatives (including bacterial membrane vesicles and hybrid membrane biomaterials) in tumor vaccines. Subsequently, the authors delve into the preparation and advantages of tumor vaccines based on bacterial membranes and hybrid membrane biomaterials. Following this, the immune effects of tumor vaccines based on bacterial outer membrane vesicles are elucidated, and their mechanisms are explained. Moreover, their advantages in tumor combination therapy are analyzed. Last, the challenges and trends in this field are discussed. This comprehensive analysis aims to offer a more informed reference and scientific foundation for the design and implementation of bacterial membrane-based tumor vaccines.

Engineered Microorganisms for Advancing Tumor Therapy

Engineered microorganisms have attracted significant interest as a unique therapeutic platform in tumor treatment. Compared with conventional cancer treatment strategies, engineering microorganism-based systems provide various distinct advantages, such as the intrinsic capability in targeting tumors, their inherent immunogenicity, in situ production of antitumor agents, and multiple synergistic functions to fight against tumors. Herein, the design, preparation, and application of the engineered microorganisms for advanced tumor therapy are thoroughly reviewed. This review presents a comprehensive survey of innovative tumor therapeutic strategies based on a series of representative engineered microorganisms, including bacteria, viruses, microalgae, and fungi. Specifically, it offers extensive analyses of the design principles, engineering strategies, and tumor therapeutic mechanisms, as well as the advantages and limitations of different engineered microorganism-based systems. Finally, the current challenges and future research prospects in this field, which can inspire new ideas for the design of creative tumor therapy paradigms utilizing engineered microorganisms and facilitate their clinical applications, are discussed.

Cell-membrane engineering strategies for clinic-guided design of nanomedicine

Cells are the fundamental units of life. The cell membrane primarily composed of two layers of phospholipids (a bilayer) structurally defines the boundary of a cell, which can protect its interior from external disturbances and also selectively exchange substances and conduct signals from the extracellular environment. The complexity and particularity of transmembrane proteins provide the foundation for versatile cellular functions. Nanomedicine as an emerging therapeutic strategy holds tremendous potential in the healthcare field. However, it is susceptible to recognition and clearance by the immune system. To overcome this bottleneck, the technology of cell membrane coating has been extensively used in nanomedicines for their enhanced therapeutic efficacy, attributed to the favorable fluidity and biocompatibility of cell membranes with various membrane-anchored proteins. Meanwhile, some engineering strategies of cell membranes through various chemical, physical and biological ways have been progressively developed to enable their versatile therapeutic functions against complex diseases. In this review, we summarized the potential clinical applications of four typical cell membranes, elucidated their underlying therapeutic mechanisms, and outlined their current engineering approaches. In addition, we further discussed the limitation of this technology of cell membrane coating in clinical applications, and possible solutions to address these challenges.

Advances in Nanomaterials for Immunotherapeutic Improvement of Cancer Chemotherapy

Immuno-stimulative effect of chemotherapy (ISECT) is recognized as a potential alternative to conventional immunotherapies, however, the clinical application is constrained by its inefficiency. Metronomic chemotherapy, though designed to overcome these limitations, offers inconsistent results, with effectiveness varying based on cancer types, stages, and patient-specific factors. In parallel, a wealth of preclinical nanomaterials holds considerable promise for ISECT improvement by modulating the cancer-immunity cycle. In the area of biomedical nanomaterials, current literature reviews mainly concentrate on a specific category of nanomaterials and nanotechnological perspectives, while two essential issues are still lacking, i.e., a comprehensive analysis addressing the causes for ISECT inefficiency and a thorough summary elaborating the nanomaterials for ISECT improvement. This review thus aims to fill these gaps and catalyze further development in this field. For the first time, this review comprehensively discusses the causes of ISECT inefficiency. It then meticulously categorizes six types of nanomaterials for improving ISECT. Subsequently, practical strategies are further proposed for addressing inefficient ISECT, along with a detailed discussion on exemplary nanomedicines. Finally, this review provides insights into the challenges and perspectives for improving chemo-immunotherapy by innovations in nanomaterials.

Cell Membrane-Coated Biomimetic Nanoparticles in Cancer Treatment

Nanoparticle-based drug delivery systems hold promise for cancer treatment by enhancing the solubility and stability of anti-tumor drugs. Nonetheless, the challenges of inadequate targeting and limited biocompatibility persist. In recent years, cell membrane nano-biomimetic drug delivery systems have emerged as a focal point of research and development, due to their exceptional traits, including precise targeting, low toxicity, and good biocompatibility. This review outlines the categorization and advantages of cell membrane bionic nano-delivery systems, provides an introduction to preparation methods, and assesses their applications in cancer treatment, including chemotherapy, gene therapy, immunotherapy, photodynamic therapy, photothermal therapy, and combination therapy. Notably, the review delves into the challenges in the application of various cell membrane bionic nano-delivery systems and identifies opportunities for future advancement. Embracing cell membrane-coated biomimetic nanoparticles presents a novel and unparalleled avenue for personalized tumor therapy.

An On-Demand Collaborative Innate-Adaptive Immune Response to Infection Treatment

Deep tissue infection is a common clinical issue and therapeutic difficulty caused by the disruption of the host antibacterial immune function, resulting in treatment failure and infection relapse. Intracellular pathogens are refractory to elimination and can manipulate host cell biology even after appropriate treatment, resulting in a locoregional immunosuppressive state that leads to an inadequate response to conventional anti-infective therapies. Here, a novel antibacterial strategy involving autogenous immunity using a biomimetic nanoparticle (NP)-based regulating system is reported to induce in situ collaborative innate-adaptive immune responses. It is observed that a macrophage membrane coating facilitates NP enrichment at the infection site, followed by active NP accumulation in macrophages in a mannose-dependent manner. These NP-armed macrophages exhibit considerably improved innate capabilities, including more efficient intracellular ROS generation and pro-inflammatory factor secretion, M1 phenotype promotion, and effective eradication of invasive bacteria. Furthermore, the reprogrammed macrophages direct T cell activation at infectious sites, resulting in a robust adaptive antimicrobial immune response to ultimately achieve bacterial clearance and prevent infection relapse. Overall, these results provide a conceptual framework for a novel macrophage-based strategy for infection treatment via the regulation of autogenous immunity.

Engineered Cell Membrane-Camouflaged Nanomaterials for Biomedical Applications

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

Immunoactivity of a hybrid membrane biosurface on nanoparticles: enhancing interactions with dendritic cells to augment anti-tumor immune responses

Nano-biointerfaces play a pivotal role in determining the functionality of engineered therapeutic nanoparticles, particularly in the context of designing nanovaccines to effectively activate immune cells for cancer immunotherapy. Unlike involving chemical reactions by conventional surface decorating strategies, cell membrane-coating technology offers a straightforward approach to endow nanoparticles with natural biosurfaces, enabling them to mimic and integrate into the intricate biosystems of the body to interact with specific cells under physiological conditions. In this study, cell membranes, in a hybrid formulation, derived from cancer and activated macrophage cells were found to enhance the interaction of nanoparticles (HMP) with dendritic cells (DCs) and T cells among the mixed immune cells from lymph nodes (LNs), which could be leveraged in the development of nanovaccines for anti-tumor therapy. After loading with an adjuvant (R837), the nanoparticles coated with a hybrid membrane (HMPR) demonstrated effectiveness in priming DCs both in vitro and in vivo, resulting in amplified anti-tumor immune responses compared to those of nanoparticles coated with a single type of membrane or those lacking a membrane coating. The elevated immunoactivity of nanoparticles achieved by incorporating a hybrid membrane biosurface provides us a more profound comprehension of the nano-immune interaction, which may significantly benefit the development of bioactive nanomaterials for advanced therapy.

Biomimetic Nano-Drug Delivery System: An Emerging Platform for Promoting Tumor Treatment

With the development of nanotechnology, nanoparticles (NPs) have shown broad prospects as drug delivery vehicles. However, they exhibit certain limitations, including low biocompatibility, poor physiological stability, rapid clearance from the body, and nonspecific targeting, which have hampered their clinical application. Therefore, the development of novel drug delivery systems with improved biocompatibility and high target specificity remains a major challenge. In recent years, biofilm mediated biomimetic nano-drug delivery system (BNDDS) has become a research hotspot focus in the field of life sciences. This new biomimetic platform uses bio-nanotechnology to encapsulate synthetic NPswithin biomimetic membrane, organically integrating the low immunogenicity, low toxicity, high tumor targeting, good biocompatibility of the biofilm with the adjustability and versatility of the nanocarrier, and shows promising applications in the field of precision tumor therapy. In this review, we systematically summarize the new progress in BNDDS used for optimizing drug delivery, providing a theoretical reference for optimizing drug delivery and designing safe and efficient treatment strategies to improve tumor treatment outcomes.

Cell membrane-based biomimetic technology for cancer phototherapy: Mechanisms, recent advances and perspectives

Despite significant advances in medical technology and antitumour treatments, the diagnosis and treatment of tumours have undergone remarkable transformations. Noninvasive phototherapy methods, such as photodynamic therapy (PDT) and photothermal therapy (PTT), have gained significant interest in antitumour medicine. However, traditional photosensitisers or photothermal agents face challenges like immune system recognition, rapid clearance from the bloodstream, limited tumour accumulation, and phototoxicity concerns. Researchers combine photosensitisers or photothermal agents with natural cell membranes to overcome these obstacles to create a nano biomimetic therapeutic platform. When used to coat nanoparticles, red blood cells, platelets, cancer cells, macrophages, lymphocytes, and bacterial outer membranes could provide prolonged circulation, tumour targeting, immune stimulation, or antigenicity. This article covers the principles of cellular membrane biomimetic nanotechnology and phototherapy, along with recent advancements in applying nano biomimetic technology to PDT, PTT, PCT, and combined diagnosis and treatment. Furthermore, the challenges and issues of using nano biomimetic nanoparticles in phototherapy are discussed. STATEMENT OF SIGNIFICANCE: Currently, there has been significant progress in the field of cell membrane biomimetic technology. Researchers are exploring its potential application in tumor diagnosis and treatment through phototherapy. Scholars have conducted extensive research on combining cell membrane technology and phototherapy in anticancer diagnosis and treatment. This review aims to highlight the mechanisms of phototherapy and the latest advancements in single phototherapy (PTT, PDT) and combination phototherapy (PCT, PRT, and PIT), as well as diagnostic approaches. The review provides an overview of various cell membrane technologies, including RBC membranes, platelet membranes, macrophage cell membranes, tumour cell membranes, bacterial membranes, hybrid membranes, and their potential for anticancer applications under phototherapy. Lastly, the review discusses the challenges and future directions in this field.

Advances in Composite Biofilm Biomimetic Nanodrug Delivery Systems for Cancer Treatment

Single biofilm biomimetic nanodrug delivery systems based on single cell membranes, such as erythrocytes and cancer cells, have immune evasion ability, good biocompatibility, prolonged blood circulation, and high tumor targeting. Because of the different characteristics and functions of each single cell membrane, more researchers are using various hybrid cell membranes according to their specific needs. This review focuses on several different types of biomimetic nanodrug-delivery systems based on composite biofilms and looks forward to the challenges and possible development directions of biomimetic nanodrug-delivery systems based on composite biofilms to provide reference and ideas for future research.

Recent Advances in the Development of Membrane-derived Vesicles for Cancer Immunotherapy

The surface proteins on cell membranes enable the cells to have different properties, such as high biocompatibility, surface modifiability, and homologous targeting ability. Cell-membrane-derived vesicles have features identical to those of their parental cells, which makes them one of the most promising materials for drug delivery. Recently, as a result of the impressive effects of immunotherapy in cancer treatment, an increasing number of researchers have used cell-membrane-derived vesicles to enhance immune responses. To be more specific, the membrane vesicles derived from immune cells, tumor cells, bacteria, or engineered cells have the antigen presentation capacity and can trigger strong anti-tumor effects of the immune system. In this review, we first indicated a brief description of the vesicles and then introduced the detection technology and drug-loading methods for them. Secondly, we concluded the characteristics and applications of vesicles derived from different sources in cancer immunotherapy.

Dendritic Cell-Based In Situ Nanovaccine for Reprogramming Lipid Metabolism to Boost Tumor Immunotherapy

Cancer vaccines have been considered to be an alternative therapeutic strategy for tumor therapy in the past decade. However, the popularity and efficacy of cancer vaccines were hampered by tumor antigen heterogeneity and the impaired function of cross-presentation in the tumor-infiltrating dendritic cells (TIDCs). To overcome these challenges, we engineered an in situ nanovaccine (named as TPOP) based on lipid metabolism-regulating and innate immune-stimulated nanoparticles. TPOP could capture tumor antigens and induce specific recognition by TIDCs to be taken up. Meanwhile, TPOP could manipulate TIDC lipid metabolism and inhibit de novo synthesis of fatty acids, thus improving the ability of TIDCs to cross-present by reducing their lipid accumulation. Significantly, intratumoral injection of TPOP combined with pretreatment with doxorubicin showed a considerable therapeutic effect in the subcutaneous mouse colorectal cancer model and melanoma model. Moreover, in combination with immune checkpoint inhibitors, such TPOP could markedly inhibit the growth of distant tumors by systemic antitumor immune responses. This work provides a safe and promising strategy for improving the function of immune cells by manipulating their metabolism and activating the immune system effectively for in situ cancer vaccines.

Progress of cell membrane-derived biomimetic nanovesicles for cancer phototherapy

In recent years, considerable attention has been given to phototherapy, including photothermal and photodynamic therapy to kill tumor cells by producing heat or reactive oxygen species (ROS). It has the high merits of noninvasiveness and limited drug resistance. To fully utilize this therapy, an extraordinary nanovehicle is required to target phototherapeutic agents in the tumor cells. Nanovesicles embody an ideal strategy for drug delivery applications. Cell membrane-derived biomimetic nanovesicles represent a developing type of nanocarrier. Combining this technique with cancer phototherapy could enable a novel strategy. Herein, efforts are made to describe a comprehensive overview of cell membrane-derived biomimetic nanovesicles for cancer phototherapy. The description in this review is mainly based on representative examples of exosome-derived biomimetic nanomedicine research, ranging from their comparison with traditional nanocarriers to extensive applications in cancer phototherapy. Additionally, the challenges and future prospectives for translating these for clinical application are discussed.

Promoting Intratumoral Drug Accumulation by Bio-Membrane Regulated Active Targeting for Tumor Photothermal Therapy

Introduction

Insufficient tumor permeability and inadequate nanoparticle retention continue to be significant limitations in the efficacy of anti-tumor drug therapy. Numerous studies have focused on enhancing tumor perfusion by improvement of tumor-induced endothelial leakage, often known as the enhanced permeability and retention (EPR) effect. However, these approaches have produced suboptimal therapeutic outcomes and have been associated with significant side effects. Therefore, in this study, we prepared tumor cell membrane-coated gold nanorods (GNR@TM) to enhance drug delivery in tumors through homogeneous targeting of tumor cell membranes and in situ real-time photo-controlled therapy.

Methods

Here, we fabricated GNR@TM, and characterized it using various techniques including Ultraviolet-Visible (UV-Vis) spectrophotometer, particle size analysis, potential measurement, and transmission electron microscopy (TEM). The cellular uptake and cytotoxicity of GNR@TM were analyzed by flow cytometry, confocal laser scanning microscopy (CLSM), TEM, CCK8 assay and live/dead staining. Tissue drug distribution was determined by inductively coupled plasma mass spectrometry (ICP-MS) and immunofluorescence staining. Furthermore, to evaluate the therapeutic effect, mice bearing MB49 tumors were intravenously administered with GNR@TM. Subsequently, near-infrared (NIR) laser therapy was performed, and the mice's tumor growth and body weight were monitored.

Results

The tumor cell membrane coating endowed GNR@TM with extended circulation time in vivo and homotypic targeting to tumor, thereby enhancing the accumulation of GNR@TM within tumors. Upon 780 nm laser, GNR@TM exhibited excellent photothermal conversion capability, leading to increased tumor vascular leakage. This magnification of the EPR effect induced by NIR laser further increased the accumulation of GNR@TM at the tumor site, demonstrating strong antitumor effects in vivo.

Conclusion

In this study, we successfully developed a NIR-triggered nanomedicine that increased drug accumulation in tumor through photo-controlled therapy and homotypic targeting of the tumor cell membrane. GNR@TM has been demonstrated effective suppression of tumor growth, excellent biocompatibility, and significant potential for clinical applications.

Recent advances in cancer cell bionic nanoparticles for tumour therapy

Nanoparticle-based drug delivery systems have found extensive use in delivering oncology therapeutics; however, some delivery vehicles still exhibit rapid immune clearance, lack of biocompatibility and insufficient targeting. In recent years, bionanoparticles constructed from tumour cell membranes have gained momentum as tumour-targeting therapeutic agents. Cancer cell membrane-coated nanoparticles (CCMCNPs) typically consist of a drug-loaded nanoparticle core coated with cancer cell membrane. CCMCNPs retain homologous tumour cell surface antigens, receptors and proteins, and it has been shown that the modified nanoparticles exhibit better homologous targeting, immune escape and biocompatibility. CCMCNPs are now widely used in a variety of cancer treatments, including photothermal, photodynamic and sonodynamic therapies, chemotherapy, immunotherapy, chemodynamical therapy or other combination therapies. This article presents different therapeutic approaches using multimodal antitumour therapy-combination of two or more therapies that treat tumours synergistically-based on tumour cell membrane systems. The advantages of CCMCNPs in different cancer treatments in recent years are summarised, thus, providing new strategies for cancer treatment research.

Beyond Extracellular Vesicles: Hybrid Membrane Nanovesicles as Emerging Advanced Tools for Biomedical Applications

Extracellular vesicles (EVs), involved in essential physiological and pathological processes of the organism, have emerged as powerful tools for disease treatment owing to their unique natural biological characteristics and artificially acquired advantages. However, the limited targeting ability, insufficient production yield, and low drug-loading capability of natural simplex EVs have greatly hindered their development in clinical translation. Therefore, the establishment of multifunctional hybrid membrane nanovesicles (HMNVs) with favorable adaptability and flexibility has become the key to expanding the practical application of EVs. This timely review summarizes the current progress of HMNVs for biomedical applications. Different HMNVs preparation strategies including physical, chemical, and chimera approaches are first discussed. This review then individually describes the diverse types of HMNVs based on homologous or heterologous cell membrane substances, a fusion of cell membrane and liposome, as well as a fusion of cell membrane and bacterial membrane. Subsequently, a specific emphasis is placed on the highlight of biological applications of the HMNVs toward various diseases with representative examples. Finally, ongoing challenges and prospects of the currently developed HMNVs in clinical translational applications are briefly presented. This review will not only stimulate broad interest among researchers from diverse disciplines but also provide valuable insights for the development of promising nanoplatforms in precision medicine.

Bacteria and Bacterial Components as Natural Bio-Nanocarriers for Drug and Gene Delivery Systems in Cancer Therapy

Bacteria and bacterial components possess multifunctional properties, making them attractive natural bio-nanocarriers for cancer diagnosis and targeted treatment. The inherent tropic and motile nature of bacteria allows them to grow and colonize in hypoxic tumor microenvironments more readily than conventional therapeutic agents and other nanomedicines. However, concerns over biosafety, limited antitumor efficiency, and unclear tumor-targeting mechanisms have restricted the clinical translation and application of natural bio-nanocarriers based on bacteria and bacterial components. Fortunately, bacterial therapies combined with engineering strategies and nanotechnology may be able to reverse a number of challenges for bacterial/bacterial component-based cancer biotherapies. Meanwhile, the combined strategies tend to enhance the versatility of bionanoplasmic nanoplatforms to improve biosafety and inhibit tumorigenesis and metastasis. This review summarizes the advantages and challenges of bacteria and bacterial components in cancer therapy, outlines combinatorial strategies for nanocarriers and bacterial/bacterial components, and discusses their clinical applications.

Bacterial extracellular vesicles: Emerging nanoplatforms for biomedical applications

Bacterial extracellular vesicles (BEVs) are nanosized lipid bilayers generated from membranes that are filled with components derived from bacteria. BEVs are important for the physiology, pathogenicity, and interactions between bacteria and their hosts as well. BEVs represent an important mechanism of transport and interaction between cells. Recent advances in biomolecular nanotechnology have enabled the desired properties to be engineered on the surface of BEVs and decoration with desired and diverse biomolecules and nanoparticles, which have potential biomedical applications. BEVs have been the focus of various fields, including nanovaccines, therapeutic agents, and drug delivery vehicles. In this review, we delineate the fundamental aspects of BEVs, including their biogenesis, cargo composition, function, and interactions with host cells. We comprehensively summarize the factors influencing the biogenesis of BEVs. We further highlight the importance of the isolation, purification, and characterization of BEVs because they are essential processes for potential benefits related to host-microbe interactions. In addition, we address recent advancements in BEVs in biomedical applications. Finally, we provide conclusions and future perspectives as well as highlight the remaining challenges of BEVs for different biomedical applications.

Biogenetic Vesicle-Based Cancer Vaccines with Tunable Surface Potential and Immune Potency

Cancer vaccines are designed to motivate antigen-specific immune responses and facilitate tumor regression with minimal side effects. To fully exert the potential of vaccines, rationally designed formulations that effectively deliver antigens and trigger potent immune reactions are urgently needed. This study demonstrates a simple and controllable vaccine-developing strategy that assembles tumor antigens into bacterial outer membrane vesicles (OMVs), natural delivery vehicles with intrinsic immune adjuvant properties, via electrostatic interaction. This OMV-delivered vaccine (OMVax) stimulated both innate and adaptive immune responses, leading to enhanced metastasis inhibition and prolonged survival of tumor-bearing mice. Moreover, the influence of different surface charged OMVax on antitumor immunity activation is investigated and declined immune response activation occurred with increased positive surface charge. Together, these findings suggest a simple vaccine formulation that can be enhanced by optimizing the surface charges of vaccine formulations.

A Yeast Cell Wall Derived Hybrid Hydrogel with Photothermal and Immune Combined Modality Therapy for Enhanced Anti-Melanoma Efficacy

Introduction

The effect of traditional treatment for melanoma is quite limited, especially for its recurrence. As the major components of yeast cell wall, chitin and β-glucan exhibit good immune activation effect and are promising candidates for adjuvant. Therefore, melanoma cell membrane (CM) and indocyanine green (ICG) was loaded in a chitin and β-glucan hybrid hydrogel to achieve an enhanced anti-melanoma therapy.

Methods

The novel hybrid hydrogel was prepared, and its physicochemical properties were examined. Its effect towards melanoma prevention and treatment was evaluated via a melanoma-bearing mice model.

Results

The CM-ICG-hybrid hydrogel was successfully prepared with excellent injectability, self-healing, drug loading, rheological, in vitro and in vivo photothermal stability, and retention properties. It also exhibited good cellular and in vivo safety profiles. In the primary melanoma mice model, it quickly ablated the in-situ melanoma, effectively inhibited the tumor growth, increased the survival rate of melanoma-bearing mice, and increased the level of IFN-γ and TNF-α. In the distal secondary melanoma model, it efficiently prevented the reoccurrence of melanoma and activated the memory T cells. In both models, a synergistic effect of photothermal therapy and immune therapy was found. The hydrogel effectively recruited CD3+ CD4+ T cells and CD3+ CD8+ T cells, inhibited the proliferation of melanoma cells, and induced the apoptosis of melanoma cells.

Conclusion

The hybrid hydrogel was successfully prepared, and it showed excellent efficacy towards melanoma prevention and treatment due to its efficient tumor ablation and immune activation capability.

A PD-L1 targeting nanotheranostic for effective photoacoustic imaging guided photothermal-immunotherapy of tumor

Tumor immunotherapy has been partly effective for specific cancers. However, problems such as low immune response, limited antitumor effectiveness, and high antibody costs still persist. Synergistic therapeutic approaches, such as immune checkpoint inhibition in conjunction with photothermal therapy and photoacoustic imaging, are expected to provide approaches for more precise and efficient immunotherapy of tumors. Furthermore, developing alternatives for antibodies, such as PD-L1 aptamers and nanocarriers, would reduce the cost of tumor immunotherapy. Herein, we develop a PD-L1-targeting nanotheranostic to block immune checkpoints for synergistic photothermal-immunotherapy against tumors, along with effective photoacoustic (PA) imaging. The nanotheranostic is synthesized by the modification of gold nanorods (GNRs) with the PD-L1 aptamer (APDL1), which can sensitively and specifically recognize PD-L1 on the tumor cell surface, and mediate nanoparticle accumulation and strong PA signals in tumors. The aptamer is released from GNR through a competition of glutathione (GSH) and is then functionalized as a PD-L1 blockade. In collaboration with the concurrent photothermal therapy, antitumor immunity is significantly augmented by enhancing the filtration of matured dendritic cells and suppressing regulatory T cells, followed by the activation of cytotoxic T cells and inhibition of T cell exhaustion. Such a nanotheranostic modality effectively suppresses tumor growth in mice, representing an appealing platform for both biological imaging and photoimmunotherapy of tumors.

Recent progress on near-infrared fluorescence heptamethine cyanine dye-based molecules and nanoparticles for tumor imaging and treatment

Recenly, near-infrared fluorescence heptamethine cyanine dyes have shown satisfactory values in bioengineering, biology, and pharmacy especially in cancer diagnosis and treatment, owing to their excellent fluorescence property and biocompatibility. In order to achieve broad application prospects, diverse structures, and chemical properties of heptamethine cyanine dyes have been designed to develop novel functional molecules and nanoparticles over the past decade. For fluorescence and photoacoustic tumor imaging properties, heptamethine cyanine dyes are equipped with good photothermal performance and reactive oxygen species production properties under near-infrared light irradiation, thus holding great promise in photodynamic and/or photothermal cancer therapies. This review offers a comprehensive scope of the structures, comparisons, and applications of heptamethine cyanine dyes-based molecules as well as nanoparticles in tumor treatment and imaging in current years. Therefore, this review may drive the development and innovation of heptamethine cyanine dyes, significantly offering opportunities for improving tumor imaging and treatment in a precise noninvasive manner. This article is categorized under: Diagnostic Tools > In Vivo Nanodiagnostics and Imaging Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Bacteria-based immunotherapy for cancer: a systematic review of preclinical studies

Immunotherapy has been emerging as a powerful strategy for cancer management. Recently, accumulating evidence has demonstrated that bacteria-based immunotherapy including naive bacteria, bacterial components, and bacterial derivatives, can modulate immune response via various cellular and molecular pathways. The key mechanisms of bacterial antitumor immunity include inducing immune cells to kill tumor cells directly or reverse the immunosuppressive microenvironment. Currently, bacterial antigens synthesized as vaccine candidates by bioengineering technology are novel antitumor immunotherapy. Especially the combination therapy of bacterial vaccine with conventional therapies may further achieve enhanced therapeutic benefits against cancers. However, the clinical translation of bacteria-based immunotherapy is limited for biosafety concerns and non-uniform production standards. In this review, we aim to summarize immunotherapy strategies based on advanced bacterial therapeutics and discuss their potential for cancer management, we will also propose approaches for optimizing bacteria-based immunotherapy for facilitating clinical translation.

In Situ Formed ROS-Responsive Hydrogel with STING Agonist and Gemcitabine to Intensify Immunotherapy against Pancreatic Ductal Adenocarcinoma

Immunotherapy, the most revolutionary anticancer strategy, faces major obstacles in yielding desirable outcomes in pancreatic ductal adenocarcinoma (PDAC) due to the highly immunosuppressive tumor microenvironment (TME). Meanwhile, when used alone, the traditional first-line chemotherapeutic agent gemcitabine (GEM) in PDAC treatment is also insufficient to achieve lasting efficacy. In this study, a reactive oxygen species degradable hydrogel system, denoted as GEM-STING@Gel, is engineered to codeliver gemcitabine and the stimulator of interferon genes (STING) agonist DMXAA (5,6-dimethylxanthenone-4-acetic acid) into the tumor site. In this work, the strategy addresses the major challenges of current immunotherapies with a facile platform, which can synergistically activate innate immunity and promote the cytotoxic T lymphocytes infiltration at the tumor site, thereby modulating the immunosuppressive TME. Further, the efficient therapeutic potency of the immunotherapy is confirmed in an orthotopic postsurgical model, unleashing the translational potential to prevent tumor recurrence after surgical resection. This study underscores the advantages of this integrative strategy that combines chemotherapy, immunotherapy, and biomaterial-based hydrogel, including improved therapeutic efficacy, operational convenience, and superior biosafety.

Adjuvant physiochemistry and advanced nanotechnology for vaccine development

Vaccines comprising innovative adjuvants are rapidly reaching advanced translational stages, such as the authorized nanotechnology adjuvants in mRNA vaccines against COVID-19 worldwide, offering new strategies to effectively combat diseases threatening human health. Adjuvants are vital ingredients in vaccines, which can augment the degree, extensiveness, and longevity of antigen specific immune response. The advances in the modulation of physicochemical properties of nanoplatforms elevate the capability of adjuvants in initiating the innate immune system and adaptive immunity, offering immense potential for developing vaccines against hard-to-target infectious diseases and cancer. In this review, we provide an essential introduction of the basic principles of prophylactic and therapeutic vaccination, key roles of adjuvants in augmenting and shaping immunity to achieve desired outcomes and effectiveness, and the physiochemical properties and action mechanisms of clinically approved adjuvants for humans. We particularly focus on the preclinical and clinical progress of highly immunogenic emerging nanotechnology adjuvants formulated in vaccines for cancer treatment or infectious disease prevention. We deliberate on how the immune system can sense and respond to the physicochemical cues (e.g., chirality, deformability, solubility, topology, and chemical structures) of nanotechnology adjuvants incorporated in the vaccines. Finally, we propose possible strategies to accelerate the clinical implementation of nanotechnology adjuvanted vaccines, such as in-depth elucidation of nano-immuno interactions, antigen identification and optimization by the deployment of high-dimensional multiomics analysis approaches, encouraging close collaborations among scientists from different scientific disciplines and aggressive exploration of novel nanotechnologies.

Macrophage-Cancer Hybrid Membrane-Camouflaged Nanoplatforms for HIF-1α Gene Silencing-Enhanced Sonodynamic Therapy of Glioblastoma

Fabrication of ingenious nanomedicines to penetrate the blood-brain barrier (BBB) and blood-brain-tumor barrier (BBTB) for efficient glioblastoma (GBM) therapy remains a big challenge. In this work, macrophage-cancer hybrid membrane-camouflaged nanoplatforms were fabricated for target gene silencing-enhanced sonodynamic therapy (SDT) of GBM. The J774.A.1 macrophage cell membrane and the U87 glioblastoma cell membrane were fused to create a hybrid biomembrane (JUM) with good BBB penetration and glioblastoma targeting capability for camouflaging. The ZIF-8 nanoparticles were synthesized for indocyanine green (ICG) and HIF-1α siRNA encapsulation (ICG-siRNA@ZIF-8, ISZ) with a high loading efficiency. After accumulation in the tumor sites, the pH sensitivity of the nanoplatform enabled release of ICG and HIF-1α siRNA in the tumor cells. Then, the expression of HIF-1α could be efficiently inhibited by the released HIF-1α siRNA to increase the SDT efficiency under hypoxic conditions. In vitro and in vivo experiments revealed that ISZ@JUM showed good BBB penetration and brain tumor-targeting capability and could achieve effective gene silencing-enhanced SDT, demonstrating great promise for clinical applications.

The Two Faces of Bacterial Membrane Vesicles: Pathophysiological Roles and Therapeutic Opportunities

Bacterial membrane vesicles (MVs) are nanosized lipid particles secreted by lysis or blebbing mechanisms from Gram-negative and -positive bacteria. It is becoming increasingly evident that MVs can promote antimicrobial resistance but also provide versatile opportunities for therapeutic exploitation. As non-living facsimiles of parent bacteria, MVs can carry multiple bioactive molecules such as proteins, lipids, nucleic acids, and metabolites, which enable them to participate in intra- and interspecific communication. Although energetically costly, the release of MVs seems beneficial for bacterial fitness, especially for pathogens. In this review, we briefly discuss the current understanding of diverse MV biogenesis routes affecting MV cargo. We comprehensively highlight the physiological functions of MVs derived from human pathogens covering in vivo adaptation, colonization fitness, and effector delivery. Emphasis is given to recent findings suggesting a vicious cycle of MV biogenesis, pathophysiological function, and antibiotic therapy. We also summarize potential therapeutical applications, such as immunotherapy, vaccination, targeted delivery, and antimicrobial potency, including their experimental validation. This comparative overview identifies common and unique strategies for MV modification used along diverse applications. Thus, the review summarizes timely aspects of MV biology in a so far unprecedented combination ranging from beneficial function for bacterial pathogen survival to future medical applications.

Biomimetic and bioinspired nano-platforms for cancer vaccine development

The advent of immunotherapy has revolutionized the treating modalities of cancer. Cancer vaccine, aiming to harness the host immune system to induce a tumor-specific killing effect, holds great promises for its broad patient coverage, high safety, and combination potentials. Despite promising, the clinical translation of cancer vaccines faces obstacles including the lack of potency, limited options of tumor antigens and adjuvants, and immunosuppressive tumor microenvironment. Biomimetic and bioinspired nanotechnology provides new impetus for the designing concepts of cancer vaccines. Through mimicking the stealth coating, pathogen recognition pattern, tissue tropism of pathogen, and other irreplaceable properties from nature, biomimetic and bioinspired cancer vaccines could gain functions such as longstanding, targeting, self-adjuvanting, and on-demand cargo release. The specific behavior and endogenous molecules of each type of living entity (cell or microorganism) offer unique features to cancer vaccines to address specific needs for immunotherapy. In this review, the strategies inspired by eukaryotic cells, bacteria, and viruses will be overviewed for advancing cancer vaccine development. Our insights into the future cancer vaccine development will be shared at the end for expediting the clinical translation.

Nanotechnology-based photo-immunotherapy: a new hope for inhibition of melanoma growth and metastasis

Melanoma is the most aggressive form of skin cancer and there is a need for the development of effective anti-melanoma therapies as it shows high metastatic ability and low response rate. In addition, it has been identified that traditional phototherapy could trigger immunogenic cell death (ICD) to activate antitumor immune response, which could not only effectively arrest primary tumor growth, but also exhibit superior effects in terms of anti-metastasis, anti-recurrence for metastatic melanoma treatment However, the limited tumor accumulation of photosensitizers/photothermal agents and immunosuppressive tumor microenvironment severely weaken the immune effects. The application of nanotechnology facilitates a higher accumulation of photosensitizers/photothermal agents at the tumor site, which can thus improve the antitumor effects of photo-immunotherapy (PIT). In this review, we summarize the basic principles of nanotechnology-based PIT and highlight novel nanotechnologies that are expected to enhance the antitumor immune response for improved therapeutic efficacy.

Biomimetic Active Materials Guided Immunogenic Cell Death for Enhanced Cancer Immunotherapy

Despite immunotherapy emerging as a vital approach to improve cancer treatment, the activation of efficient immune responses is still hampered by immunosuppression, especially due to the low tumor immunogenicity. Immunogenic cell death (ICD) is a promising strategy to reshape the tumor microenvironment (TME) for achieving high immunogenicity. Various stimuli are able to effectively initiate their specific ICD by utilizing the corresponding ICD-inducer. However, the ICD-guided antitumor immune effects are usually impaired by various biological barriers and TME-associated immune resistance. Biomimetic active materials are being extensively explored as guided agents for ICD due to their unique advantages. In this review, two major strategies are systematically introduced that have been employed to exploit biomimetic active materials guided ICD for cancer immunotherapy, mainly including naive organism-derived nanoagents and engineered bioactive platforms. This review outlines the recent advances in the field at biomimetic active materials guided physiotherapy, chemotherapy, and biotherapy for ICD induction. The advances and challenges of biomimetic active materials guided ICD for cancer immunotherapy applications are further discussed in future clinical practice. This review provides an overview of the advances of biomimetic active materials for targeting immunoregulation and treatment and can contribute to the future of advanced antitumor combination therapy.

Interactions between extracellular vesicles and microbiome in human diseases: New therapeutic opportunities

In recent decades, accumulating research on the interactions between microbiome homeostasis and host health has broadened new frontiers in delineating the molecular mechanisms of disease pathogenesis and developing novel therapeutic strategies. By transporting proteins, nucleic acids, lipids, and metabolites in their versatile bioactive molecules, extracellular vesicles (EVs), natural bioactive cell-secreted nanoparticles, may be key mediators of microbiota-host communications. In addition to their positive and negative roles in diverse physiological and pathological processes, there is considerable evidence to implicate EVs secreted by bacteria (bacterial EVs [BEVs]) in the onset and progression of various diseases, including gastrointestinal, respiratory, dermatological, neurological, and musculoskeletal diseases, as well as in cancer. Moreover, an increasing number of studies have explored BEV-based platforms to design novel biomedical diagnostic and therapeutic strategies. Hence, in this review, we highlight the recent advances in BEV biogenesis, composition, biofunctions, and their potential involvement in disease pathologies. Furthermore, we introduce the current and emerging clinical applications of BEVs in diagnostic analytics, vaccine design, and novel therapeutic development.

Recent Developments in Nanoparticle-Based Photo-Immunotherapy for Cancer Treatment

Phototherapy is an emerging approach for cancer treatment that is effective at controlling the growth of primary tumors. In the presence of light irradiation, photothermal and photodynamic agents that are delivered to tumor sites can induce local hyperthermia and the production of reactive oxygen species, respectively, that directly eradicate cancer cells. Nanoparticles, characterized by their small size and tunable physiochemical properties, have been widely utilized as carriers for phototherapeutic agents to improve their biocompatibility and tumor-targeted delivery. Nanocarriers can also be used to implement various codelivery strategies for further enhancing phototherapeutic efficiency. More recently, there has been considerable interest in augmenting the immunological effects of nanoparticle-based phototherapies, which can yield durable and systemic antitumor responses. This review provides an overview of recent developments in using nanoparticle technology to achieve photo-immunotherapy.

Bacterial-Mediated Tumor Therapy: Old Treatment in a New Context

Targeted therapy and immunotherapy have brought hopes for precision cancer treatment. However, complex physiological barriers and tumor immunosuppression result in poor efficacy, side effects, and resistance to antitumor therapies. Bacteria-mediated antitumor therapy provides new options to address these challenges. Thanks to their special characteristics, bacteria have excellent ability to destroy tumor cells from the inside and induce innate and adaptive antitumor immune responses. Furthermore, bacterial components, including bacterial vesicles, spores, toxins, metabolites, and other active substances, similarly inherit their unique targeting properties and antitumor capabilities. Bacteria and their accessory products can even be reprogrammed to produce and deliver antitumor agents according to clinical needs. This review first discusses the role of different bacteria in the development of tumorigenesis and the latest advances in bacteria-based delivery platforms and the existing obstacles for application. Moreover, the prospect and challenges of clinical transformation of engineered bacteria are also summarized.

Versatile biomimetic nanomedicine for treating cancer and inflammation disease

Nanosized drug delivery systems (NDDSs) have emerged as a powerful tool to optimize drug delivery in complex diseases, including cancer and inflammation. However, the therapeutic effect of NDDSs is still far from satisfactory due to their poor circulation time, low delivery efficiency, and innate toxicity. Fortunately, biomimetic approaches offer new opportunities to develop nanomedicine, which is derived from a variety of native biomolecules including cells, exosomes, bacteria, and so on. Since inheriting the superior biocompatibility and versatile functions of natural materials, biomimetic nanomedicine can mimic biological processes, prolong blood circulation, and lower immunogenicity, serving as a desired platform for precise drug delivery for treating cancer and inflammatory disease. In this review, we outline recent advances in biomimetic NDDSs, which consist of two concepts: biomimetic exterior camouflage and bioidentical molecule construction. We summarize engineering strategies that further functionalized current biomimetic NDDSs. A series of functional biomimetic NDDSs created by our group are introduced. We conclude with an outlook on remaining challenges and possible directions for biomimetic NDDSs. We hope that better technologies can be inspired and invented to advance drug delivery systems for cancer and inflammation therapy.

Bacterial outer membrane vesicle based versatile nanosystem boosts the efferocytosis blockade triggered tumor-specific immunity

Efferocytosis inhibition is emerging as an attractive strategy for antitumor immune therapy because of the subsequent leak of abundant immunogenic contents. However, the practical efficacy is seriously impeded by the immunosuppressive tumor microenvironments. Here, we construct a versatile nanosystem that can not only inhibit the efferocytosis but also boost the following antitumor immunity. MerTK inhibitor UNC2025 is loaded into the bacterial outer membrane vesicles (OMVs), which are then modified with maleimide (mU@OMVs). The prepared mU@OMVs effectively inhibits the efferocytosis by promoting the uptake while preventing the MerTK phosphorylation of tumor associated macrophages, and then captures the released antigens through forming universal thioether bonds. The obtained in situ vaccine effectively transfers to lymph nodes by virtue of the intrinsic features of OMVs, and then provokes intense immune responses that can efficiently prevent the growth, metastasis and recurrence of tumors in mice, providing a generalizable strategy for cancer immunotherapy.

Bacterial Membrane Vesicles as Smart Drug Delivery and Carrier Systems: A New Nanosystems Tool for Current Anticancer and Antimicrobial Therapy

Bacterial membrane vesicles (BMVs) are known to be critical communication tools in several pathophysiological processes between bacteria and host cells. Given this situation, BMVs for transporting and delivering exogenous therapeutic cargoes have been inspiring as promising platforms for developing smart drug delivery systems (SDDSs). In the first section of this review paper, starting with an introduction to pharmaceutical technology and nanotechnology, we delve into the design and classification of SDDSs. We discuss the characteristics of BMVs including their size, shape, charge, effective production and purification techniques, and the different methods used for cargo loading and drug encapsulation. We also shed light on the drug release mechanism, the design of BMVs as smart carriers, and recent remarkable findings on the potential of BMVs for anticancer and antimicrobial therapy. Furthermore, this review covers the safety of BMVs and the challenges that need to be overcome for clinical use. Finally, we discuss the recent advancements and prospects for BMVs as SDDSs and highlight their potential in revolutionizing the fields of nanomedicine and drug delivery. In conclusion, this review paper aims to provide a comprehensive overview of the state-of-the-art field of BMVs as SDDSs, encompassing their design, composition, fabrication, purification, and characterization, as well as the various strategies used for targeted delivery. Considering this information, the aim of this review is to provide researchers in the field with a comprehensive understanding of the current state of BMVs as SDDSs, enabling them to identify critical gaps and formulate new hypotheses to accelerate the progress of the field.

Smart Nanoparticle-Based Platforms for Regulating Tumor Microenvironment and Cancer Immunotherapy

Tumor development and metastasis are closely related to the tumor microenvironment (TME). Recently, several studies indicate that modulating TME can enhance cancer immunotherapy. Among various approaches to modulating TME, nanoparticles (NPs) with unique inherent advantages and smart modified characteristics are promising candidates in delivering drugs to cancer cells, amplifying the therapeutic effects, and leading to a cascade of immune responses. In this review, several smart NP-based platforms are briefly introduced, such as responsive NPs, targeting NPs, and the composition of TME, including dendritic cells, macrophages, fibroblasts, endothelial cells, myeloid-derived suppressor cells, and regulatory T cells. Moreover, the recent applications of smart NP-based platforms in regulating TME and cancer immunotherapy are briefly introduced. Last, the advantages and disadvantages of these smart NP-based platforms in potential clinical translation are discussed.

Engineering goat milk-derived extracellular vesicles for multiple bioimaging-guided and photothermal-enhanced therapy of colon cancer

Multimodal image-guided photothermal therapy (PTT) has great application potential in cancer treatment due to its advantages of low side effects and good efficacy. There is an urgent need for PTT nanocarriers with high loading efficiency and modified surfaces. Goat milk-derived extracellular vesicles (GMVs) an ideal PTT nanoplatforms due to their anti-inflammatory ability, tumor retention ability, high yield, and high biosafety. This study used GMVs to design a theranostic nanoprobe for positron emission tomography/computer tomography/near-infrared fluorescence (PET/CT/NIRF) imaging and image-guided PTT for colon cancer. The key genes, important biological processes, and important signaling pathways of indocyanine green (ICG)-mediated PTT and N₃-GMV@ICG-mediated PTT were analyzed. The nanoprobe triggered anti-tumor immune and inflammation responses to enhance PTT. In addition, the nanoprobe could attenuate PTT-induced inflammation benefiting from the anti-inflammatory efficacy of GMVs. Therefore, our findings conceptually advanced the diagnosis and treatment of colon cancer. We believed that the nanoprobe had broad clinical transformation prospects, and GMVs might be ideal nanocarriers for constructing integrated diagnostic and PTT probes.

Bacteria-based bioactive materials for cancer imaging and therapy

Owing to the unique biological functions, bacteria as biological materials have been widely used in biomedical field. With advances in biotechnology and nanotechnology, various bacteria-based bioactive materials were developed for cancer imaging and therapy. In this review, different types of bacteria-based bioactive materials and their construction strategies were summarized. The advantages and property-function relationship of bacteria-based bioactive materials were described. Representative researches of bacteria-based bioactive materials in cancer imaging and therapy were illustrated, revealing general ideas for their construction. Also, limitation and challenges of bacteria-based bioactive materials in cancer research were discussed.

Erythrocyte-Inspired Functional Materials for Biomedical Applications

Erythrocytes are the most abundant cells in the blood. As the results of long-term natural selection, their specific biconcave discoid morphology and cellular composition are responsible for gaining excellent biological performance. Inspired by the intrinsic features of erythrocytes, various artificial biomaterials emerge and find broad prospects in biomedical applications such as therapeutic delivery, bioimaging, and tissue engineering. Here, a comprehensive review from the fabrication to the applications of erythrocyte-inspired functional materials is given. After summarizing the biomaterials mimicking the biological functions of erythrocytes, the synthesis strategies of particles with erythrocyte-inspired morphologies are presented. The emphasis is on practical biomedical applications of these bioinspired functional materials. The perspectives for the future possibilities of the advanced erythrocyte-inspired biomaterials are also discussed. It is hoped that the summary of existing studies can inspire researchers to develop novel biomaterials; thus, accelerating the progress of these biomaterials toward clinical biomedical applications.