Cytomembrane nanovaccines show therapeutic effects by mimicking tumor cells and antigen presenting cells

Application of biomimetic nanovaccines in cancer immunotherapy: A useful strategy to help combat immunotherapy resistance

Breakthroughs in actual clinical applications have begun through vaccine-based cancer immunotherapy, which uses the body's immune system, both humoral and cellular, to attack malignant cells and fight diseases. However, conventional vaccine approaches still face multiple challenges eliciting effective antigen-specific immune responses, resulting in immunotherapy resistance. In recent years, biomimetic nanovaccines have emerged as a promising alternative to conventional vaccine approaches by incorporating the natural structure of various biological entities, such as cells, viruses, and bacteria. Biomimetic nanovaccines offer the benefit of targeted antigen-presenting cell (APC) delivery, improved antigen/adjuvant loading, and biocompatibility, thereby improving the sensitivity of immunotherapy. This review presents a comprehensive overview of several kinds of biomimetic nanovaccines in anticancer immune response, including cell membrane-coated nanovaccines, self-assembling protein-based nanovaccines, extracellular vesicle-based nanovaccines, natural ligand-modified nanovaccines, artificial antigen-presenting cells-based nanovaccines and liposome-based nanovaccines. We also discuss the perspectives and challenges associated with the clinical translation of emerging biomimetic nanovaccine platforms for sensitizing cancer cells to immunotherapy.

Recent advances in biomimetic cell membrane-camouflaged nanoparticles for cancer therapy

The emerging strategy of biomimetic nanoparticles (NPs) via cellular membrane camouflage holds great promise in cancer therapy. This scholarly review explores the utilization of cellular membranes derived from diverse cellular entities; blood cells, immune cells, cancer cells, stem cells, and bacterial cells as examples of NP coatings. The camouflaging strategy endows NPs with nuanced tumor-targeting abilities such as self-recognition, homotypic targeting, and long-lasting circulation, thus also improving tumor therapy efficacy overall. The comprehensive examination encompasses a variety of cell membrane camouflaged NPs (CMCNPs), elucidating their underlying targeted therapy mechanisms and delineating diverse strategies for anti-cancer applications. Furthermore, the review systematically presents the synthesis of source materials and methodologies employed in order to construct and characterize these CMCNPs, with a specific emphasis on their use in cancer treatment.

Boosting antitumor efficacy of nanoparticles by modulating tumor mechanical microenvironment

Nanoparticles have shown great potential for tumor targeting delivery via enhanced permeability and retention effect. However, the tumor mechanical microenvironment, characterized by dense extracellular matrix (ECM), high tumor stiffness and solid stress, leads to only 0.7% of administered dose accumulating in solid tumors and even fewer (∼0.0014%) reaching tumor cells, limiting the therapeutic efficacy of nanoparticles. Furthermore, the tumor mechanical microenvironment can regulate tumor cell stemness, promote tumor invasion, metastasis and reduce treatment efficacy. In this review, methods detecting the mechanical are introduced. Strategies for modulating the mechanical microenvironment including elimination of dense ECM by physical, chemical and biological methods, disruption of ECM formation, depletion or inhibition of cancer-associated fibroblasts, are then summarized. Finally, prospects and challenges for further clinical applications of mechano-modulating strategies to enhance the therapeutic efficacy of nanomedicines are discussed. This review may provide guidance for the rational design and application of nanoparticles in clinical settings.

Engineered biological nanoparticles as nanotherapeutics for tumor immunomodulation

Biological nanoparticles, or bionanoparticles, are small molecules manufactured in living systems with complex production and assembly machinery. The products of the assembly systems can be further engineered to generate functionalities for specific purposes. These bionanoparticles have demonstrated advantages such as immune system evasion, minimal toxicity, biocompatibility, and biological clearance. Hence, bionanoparticles are considered the new paradigm in nanoscience research for fabricating safe and effective nanoformulations for therapeutic purposes. Harnessing the power of the immune system to recognize and eradicate malignancies is a viable strategy to achieve better therapeutic outcomes with long-term protection from disease recurrence. However, cancerous tissues have evolved to become invisible to immune recognition and to transform the tumor microenvironment into an immunosuppressive dwelling, thwarting the immune defense systems and creating a hospitable atmosphere for cancer growth and progression. Thus, it is pertinent that efforts in fabricating nanoformulations for immunomodulation are mindful of the tumor-induced immune aberrations that could render cancer nanotherapy inoperable. This review systematically categorizes the immunosuppression mechanisms, the regulatory immunosuppressive cellular players, and critical suppressive molecules currently targeted as breakthrough therapies in the clinic. Finally, this review will summarize the engineering strategies for affording immune moderating functions to bionanoparticles that tip the tumor microenvironment (TME) balance toward cancer elimination, a field still in the nascent stage.

Engineering customized nanovaccines for enhanced cancer immunotherapy

Nanovaccines have gathered significant attention for their potential to elicit tumor-specific immunological responses. Despite notable progress in tumor immunotherapy, nanovaccines still encounter considerable challenges such as low delivery efficiency, limited targeting ability, and suboptimal efficacy. With an aim of addressing these issues, engineering customized nanovaccines through modification or functionalization has emerged as a promising approach. These tailored nanovaccines not only enhance antigen presentation, but also effectively modulate immunosuppression within the tumor microenvironment. Specifically, they are distinguished by their diverse sizes, shapes, charges, structures, and unique physicochemical properties, along with targeting ligands. These features of nanovaccines facilitate lymph node accumulation and activation/regulation of immune cells. This overview of bespoke nanovaccines underscores their potential in both prophylactic and therapeutic applications, offering insights into their future development and role in cancer immunotherapy.

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.

In Situ Sprayed Exosome-Cross-Linked Gel as Artificial Lymph Nodes for Postoperative Glioblastoma Immunotherapy

One key challenge in postoperative glioblastoma immunotherapy is to guarantee a potent and durable T-cell response, which is restricted by the immunosuppressive microenvironment within the lymph nodes (LNs). Here, we develop an in situ sprayed exosome-cross-linked gel that acts as an artificial LN structure to directly activate the tumor-infiltrating T cells for prevention of glioma recurrence. Briefly, this gel is generated by a bio-orthogonal reaction between azide-modified chimeric exosomes and alkyne-modified alginate polymers. Particularly, these chimeric exosomes are generated from dendritic cell (DC)-tumor hybrid cells, allowing for direct and robust T-cell activation. The gel structure with chimeric exosomes as cross-linking points avoids the quick clearance by the immune system and thus prolongs the durability of antitumor T-cell immunity. Importantly, this exosome-containing immunotherapeutic gel provides chances for ameliorating functions of antigen-presenting cells (APCs) through accommodating different intracellular-acting adjuvants, such as stimulator of interferon genes (STING) agonists. This further enhances the antitumor T-cell response, resulting in the almost complete elimination of residual lesions after surgery. Our findings provide a promising strategy for postsurgical glioma immunotherapy that warrants further exploration in the clinical arena.

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.

Genetically Engineered Cytomembrane Nanovaccines for Cancer Immunotherapy

Cancer nanovaccines have attracted widespread attention by inducing potent cytotoxic T cell responses to improve immune checkpoint blockade (ICB) therapy, while the lack of co-stimulatory molecules limits their clinical applications. Here, a genetically engineered cancer cytomembrane nanovaccine is reported that simultaneously overexpresses co-stimulatory molecule CD40L and immune checkpoint inhibitor PD1 to elicit robust antitumor immunity for cancer immunotherapy. The CD40L and tumor antigens inherited from cancer cytomembranes effectively stimulate dendritic cell (DC)-mediated immune activation of cytotoxic T cells, while the PD1 on cancer cytomembranes significantly blocks PD1/PD-L1 signaling pathway, synergistically stimulating antitumor immune responses. Benefiting from the targeting ability of cancer cytomembranes, this nanovaccines formula shows an enhanced lymph node trafficking and retention. Compared with original cancer cytomembranes, this genetically engineered nanovaccine induces twofold DC maturation and shows satisfactory precaution efficacy in a breast tumor mouse model. This genetically engineered cytomembrane nanovaccine offers a simple, safe, and robust strategy by incorporating cytomembrane components and co-stimulatory molecules for enhanced cancer immunotherapy.

Piezocatalytic Schottky Junction Treats Atherosclerosis by a Biomimetic Trojan Horse Strategy

The atherosclerotic vulnerable plaque is characterized by the foamy macrophage burden, involving impaired cholesterol efflux and deficient efferocytosis. Correspondingly, piezocatalytic therapy is an emerging solution for eliminating the foamy macrophage burden with satisfactory spatiotemporal controllability and deep penetration depth. Herein, a biomimetic Trojan horse (Au-ZnO@MM) is engineered by coating the macrophage membrane (MM) onto the surface of a rod-like Au-ZnO Schottky Junction to effectively relieve the atherosclerotic progression. These Trojan horses with the coating of MM are actively transported into subsistent foamy macrophages and generate abundant reactive oxygen species (ROS) via ultrasound-activated piezocatalysis. ROS-initiated autophagy and mitochondrial dysfunction induce substantial cell apoptosis, alleviating the burden of subsistent foamy macrophages. The resulting apoptotic fragments further significantly facilitate cholesterol excretion and trigger efferocytosis of intraplaque fresh macrophages. Ultimately, the biomimetic Au-ZnO@MM piezocatalyst not only inhibits the foaming capacity of macrophages, but also improves the function of removing cell debris, which can stabilize atherosclerotic vulnerable plaque. Meanwhile, the plasmon resonance effect of integrated gold nanoparticles enables favorable photoacoustic molecular imaging for real-time image-guided atherosclerotic therapy. This proposed biomimetic Trojan horse strategy provides the paradigm of employing ultrasound-activated piezocatalytic methodology for enhanced atherosclerotic theranostics.

Hybrid Ginseng-derived Extracellular Vesicles-Like Particles with Autologous Tumor Cell Membrane for Personalized Vaccination to Inhibit Tumor Recurrence and Metastasis

Personalized cancer vaccines based on resected tumors from patients is promising to address tumor heterogeneity to inhibit tumor recurrence or metastasis. However, it remains challenge to elicit immune activation due to the weak immunogenicity of autologous tumor antigens. Here, a hybrid membrane cancer vaccine is successfully constructed by membrane fusion to enhance adaptive immune response and amplify personalized immunotherapy, which formed a codelivery system for autologous tumor antigens and immune adjuvants. Briefly, the functional hybrid vesicles (HM-NPs) are formed by hybridizing ginseng-derived extracellular vesicles-like particles (G-EVLPs) with the membrane originated from the resected autologous tumors. The introduction of G-EVLPs can enhance the phagocytosis of autologous tumor antigens by dendritic cells (DCs) and facilitate DCs maturation through TLR4, ultimately activating tumor-specific cytotoxic T lymphocytes (CTLs). HM-NPs can indeed strengthen specific immune responses to suppress tumors recurrence and metastasis including subcutaneous tumors and orthotopic tumors. Furthermore, a long-term immune protection can be obtained after vaccinating with HM-NPs, and prolonging the survival of animals. Overall, this personalized hybrid autologous tumor vaccine based on G-EVLPs provides the possibility of mitigating tumor recurrence and metastasis after surgery while maintaining good biocompatibility.

Crosstalking with Dendritic Cells: A Path to Engineer Advanced T Cell Immunotherapy

Crosstalk between dendritic cells (DCs) and T cells plays a crucial role in modulating immune responses in natural and pathological conditions. DC-T cell crosstalk is achieved through contact-dependent (i.e., immunological synapse) and contact-independent mechanisms (i.e., cytokines). Activated DCs upregulate co-stimulatory signals and secrete proinflammatory cytokines to orchestrate T cell activation and differentiation. Conversely, activated T helper cells "license" DCs towards maturation, while regulatory T cells (Tregs) silence DCs to elicit tolerogenic immunity. Strategies to efficiently modulate the DC-T cell crosstalk can be harnessed to promote immune activation for cancer immunotherapy or immune tolerance for the treatment of autoimmune diseases. Here, we review the natural crosstalk mechanisms between DC and T cells. We highlight bioengineering approaches to modulate DC-T cell crosstalk, including conventional vaccines, synthetic vaccines, and DC-mimics, and key seminal studies leveraging these approaches to steer immune response for the treatment of cancer and autoimmune diseases.

Engineered Cell Membrane-Coated Nanoparticles: New Strategies in Glioma Targeted Therapy and Immune Modulation

Gliomas, the most prevalent primary brain tumors, pose considerable challenges due to their heterogeneity, intricate tumor microenvironment (TME), and blood-brain barrier (BBB), which restrict the effectiveness of traditional treatments like surgery and chemotherapy. This review provides an overview of engineered cell membrane technologies in glioma therapy, with a specific emphasis on targeted drug delivery and modulation of the immune microenvironment. This study investigates the progress in engineered cell membranes, encompassing physical, chemical, and genetic alterations, to improve drug delivery across the BBB and effectively target gliomas. The examination focuses on the interaction of engineered cell membrane-coated nanoparticles (ECM-NPs) with the TME in gliomas, emphasizing their potential to modulate glioma cell behavior and TME to enhance therapeutic efficacy. The review further explores the involvement of ECM-NPs in immunomodulation techniques, highlighting their impact on immune reactions. While facing obstacles related to membrane stability and manufacturing scalability, the review outlines forthcoming research directions focused on enhancing membrane performance. This review underscores the promise of ECM-NPs in surpassing conventional therapeutic constraints, proposing novel approaches for efficacious glioma treatment.

Dual-Antigen-Displaying Nanovaccines Elicit Synergistic Immunoactivation for Treating Cancer and Preventing Infectious Complications

As one of the most common complications, infection causes the majority of mortality in cancer patients. However, therapeutic strategies that can simultaneously suppress tumors and protect patients from infection have been rarely reported. Here, the use of dual-antigen-displaying nanovaccines (DADNs) is described to elicit synergistic immunoactivation for treating cancer and preventing infectious complications. DADNs are prepared by wrapping immunoadjuvant-loaded nanoparticles with a hybrid coating, which is fused from cell membranes that are separately genetically engineered to express tumor and infectious pathogenic antigens. Due to the presence of a dual-antigen combination, DADNs are able to promote the maturation of dendritic cells and more importantly to trigger cross-presentation of both combined antigens. During in vivo investigations, we find that DADNs can reverse immunosuppression by stimulating tumor-associated antigen-specific T-cell responses, resulting in significantly delayed tumor growth in mice. These nanovaccines also elicit effective protective immunity against tumor challenges and induce robust production of pathogenic antigen-specific immunoglobulin G antibody in a prophylactic study. This work offers a unique approach to develop dual-mode vaccines, which are promising for synchronously treating cancer and preventing infection.

Unlocking the power of nanomedicine: Cell membrane-derived biomimetic cancer nanovaccines for cancer treatment

Over the past decades, nanomedicine researchers have dedicated their efforts to developing nanoscale platforms capable of more precisely delivering drug payloads to attack tumors. Cancer nanovaccines are exhibiting a distinctive capability in inducing tumor-specific antitumor responses. Nevertheless, there remain numerous challenges that must be addressed for cancer nanovaccines to evoke sufficient therapeutic effects. Cell membrane-derived nanovaccines are an emerging class of cancer vaccines that comprise a synthetic nanoscale core camouflaged by naturally derived cell membranes. The specific cell membrane has a biomimetic nanoformulation with several distinctive abilities, such as immune evasion, enhanced biocompatibility, and tumor targeting, typically associated with a source cell. Here, we discuss the advancements of cell membrane-derived nanovaccines and how these vaccines are used for cancer therapeutics. Translational endeavors are currently in progress, and additional research is also necessary to effectively address crucial areas of demand, thereby facilitating the future successful translation of these emerging vaccine platforms.

Cancer cell membrane-coated nanoparticles: a promising anti-tumor bionic platform

Nanoparticle (NP) drug delivery systems have shown promise in tumor therapy. However, limitations such as susceptibility to immune clearance and poor targeting in a complex intercellular environment still exist. Recently, cancer cell membrane-encapsulated nanoparticles (CCM-NPs) constructed using biomimetic nanotechnology have been developed to overcome these problems. Proteins on the membrane surface of cancer cells can provide a wide range of activities for CCM-NPs, including immune escape and homologous cell recognition properties. Meanwhile, the surface of the cancer cell membrane exhibits obvious antigen enrichment, so that CCM-NPs can transmit tumor-specific antigen, activate a downstream immune response, and produce an effective anti-tumor effect. In this review, we first provided an overview of the functions of cancer cell membranes and summarized the preparation techniques and characterization methods of CCM-NPs. Then, we focused on the application of CCM-NPs in tumor therapy. In addition, we summarized the functional modifications of cancer cell membranes and compiled the patent applications related to CCM-NPs in recent years. Finally, we proposed the future challenges and directions of this technology in order to provide guidance for researchers in this field.

Erythrocyte Membrane Camouflaged Nanotheranostics for Optical Molecular Imaging-Escorted Self-Oxygenation Photodynamic Therapy

Hypoxic tumor microenvironment (TME) hampers the application of oxygen (O2 )-dependent photodynamic therapy (PDT) in solid tumors. To address this problem, a biomimetic nanotheranostics (named MMCC@EM) is developed for optical molecular imaging-escorted self-oxygenation PDT. MMCC@EM is synthesized by encapsulating chlorin e6 (Ce6) and catalase (CAT) in metal-organic framework (MOF) nanoparticles with erythrocyte membrane (EM) camouflage. Based on the biomimetic properties of EM, MMCC@EM efficiently accumulates in tumor tissues. The enriched MMCC@EM achieves TME-activatable drug release, thereby releasing CAT and Ce6, and this process can be monitored through fluorescence (FL) imaging. In addition, endogenous hydrogen peroxide (H2 O2 ) will be decomposed by CAT to produce O2 , which can be reflected by the measurement of intratumoral oxygen concentration using photoacoustic (PA) imaging. Such self-oxygenation nanotheranostics effectively mitigate tumor hypoxia and improve the generation of singlet oxygen (1 O2 ). The 1 O2 disrupts mitochondrial function and triggers caspase-3-mediated cellular apoptosis. Furthermore, MMCC@EM triggers immunogenic cell death (ICD) effect, leading to an increased infiltration of cytotoxic T lymphocytes (CTLs) into tumor tissues. As a result, MMCC@EM exhibits good therapeutic effects in 4T1-tumor bearing mice under the navigation of FL/PA duplex imaging.

Hybrid Cellular Nanovesicles Block PD-L1 Signal and Repolarize M2 Macrophages for Cancer Immunotherapy

The PD1/PD-L1 immune checkpoint blocking is a promising therapy, while immunosuppressive tumor microenvironment (TME) and poor tumor penetration of therapeutic antibodies limit its efficacy. Repolarization of tumor-associated macrophages (TAMs) offers a potential method to ameliorate immunosuppression of TME and further boost T cell antitumor immunity. Herein, hybrid cell membrane biomimetic nanovesicles (hNVs) are developed by fusing M1 macrophage-derived nanovesicles (M1-NVs) and PD1-overexpressed tumor cell-derived nanovesicles (PD1-NVs) to improve cancer immunotherapy. The M1-NVs promote the transformation of M2-like TAMs to M1-like phenotype and further increase the release of pro-inflammatory cytokines, resulting in improved immunosuppressive TME. Concurrently, the PD1-NVs block PD1/PD-L1 pathway, which boosts cancer immunotherapy when combined with M1-NVs. In a breast cancer mouse model, the hNVs efficiently accumulate at the tumor site after intravenous injection and significantly inhibit the tumor growth. Mechanically, the M1 macrophages and CD8+ T lymphocytes in TME increase by twofold after the treatment, indicating effective immune activation. These results suggest the hNVs as a promising strategy to integrate TME improvement with PD1/PD-L1 blockade for cancer immunotherapy.

Antigen Self-Presented Personalized Nanovaccines Boost the Immunotherapy of Highly Invasive and Metastatic Tumors

Dendritic cell (DC)-based vaccines have shown promise in adoptive cell therapy for enhancing the antigen-specific response of antitumor immunity. However, their clinical efficacy is limited by the less-presented tumor-associated antigens (TAAs) through MHC I and low lymph node homing efficiency. Herein, to address these issues, we rationally design and fabricate DC-based nanovaccines by coating Cu2-xSe nanoparticles (CS NPs) with the membrane of matured DCs (named as DCNV(CSD) nanovaccines). We reveal the important roles of CS NPs in the DCNV(CSD) nanovaccines from three aspects: (1) inducing the immunogenic cell death of tumor cells to expose abundant TAAs; (2) promoting the escape of TAAs from the lysosomes of DCs during the antigen presenting process through MHC I; (3) sustainably releasing traces of copper ions to promote the proliferation of T cells. Our DCNV(CSD) nanovaccines are characterized with high expressions of MHC I, CD80, CD86, CCR7, and ICAM-1 proteins, which not only endow them with abundantly processed specific TAAs, but also a strong capability of homing to the lymph nodes. The homing capability of our small DCNV(CSD) nanovaccines is better than that of matured DCs. More importantly, they can elicit the strong response of potent antispecific CD8+ T cells for antitumor immunotherapy, as tested in the treatment of highly invasive glioblastoma and highly metastatic melanoma. Additionally, DCNV(CSD) nanovaccines can generate memory T cells (TEM) in the spleen of mice to effectively prevent the recurrence of treated tumors. This work demonstrates a universal approach to fabricate high-performance DC-based nanovaccines for tumor immunotherapy by using versatile CS NPs.

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.

The quest for nanoparticle-powered vaccines in cancer immunotherapy

Despite recent advancements in cancer treatment, this disease still poses a serious threat to public health. Vaccines play an important role in preventing illness by preparing the body's adaptive and innate immune responses to combat diseases. As our understanding of malignancies and their connection to the immune system improves, there has been a growing interest in priming the immune system to fight malignancies more effectively and comprehensively. One promising approach involves utilizing nanoparticle systems for antigen delivery, which has been shown to potentiate immune responses as vaccines and/or adjuvants. In this review, we comprehensively summarized the immunological mechanisms of cancer vaccines while focusing specifically on the recent applications of various types of nanoparticles in the field of cancer immunotherapy. By exploring these recent breakthroughs, we hope to identify significant challenges and obstacles in making nanoparticle-based vaccines and adjuvants feasible for clinical application. This review serves to assess recent breakthroughs in nanoparticle-based cancer vaccinations and shed light on their prospects and potential barriers. By doing so, we aim to inspire future immunotherapies for cancer that harness the potential of nanotechnology to deliver more effective and targeted treatments.

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.

Cancer Cell Membrane-Based Materials for Biomedical Applications

The nanodelivery system provides a novel direction for disease diagnosis and treatment; however, its delivery effectiveness is restricted by the short biological half-life and inadequate tumor targeting. The immune evasion properties and homologous targeting capabilities of natural cell membranes, particularly those of cancer cell membranes (CCM), have gained significant interest. The integration of CCM and nanoparticles has resulted in the emergence of CCM-based nanoplatforms (CCM-NPs), which have gained significant attention due to their unique properties. CCM-NPs not only prolong the blood circulation time of core nanoparticles, but also direct them for homologous tumor targeting. Herein, the history and development of CCM-NPs as well as how these platforms have been used for biomedical applications are discussed. The application of CCM-NPs for cancer therapy will be described in detail. Translational efforts are currently under way and further research to address key areas of need will ultimately be required to facilitate the successful clinical adoption of CCM-NPs.

Chimeric Exosomes Functionalized with STING Activation for Personalized Glioblastoma Immunotherapy

A critical challenge of existing cancer vaccines is to orchestrate the demands of antigen-enriched furnishment and optimal antigen-presentation functionality within antigen-presenting cells (APCs). Here, a complementary immunotherapeutic strategy is developed using dendritic cell (DC)-tumor hybrid cell-derived chimeric exosomes loaded with stimulator of interferon genes (STING) agonists (DT-Exo-STING) for maximized tumor-specific T-cell immunity. These chimeric carriers are furnished with broad-spectrum antigen complexes to elicit a robust T-cell-mediated inflammatory program through direct self-presentation and indirect DC-to-T immunostimulatory pathway. This chimeric exosome-assisted delivery strategy possesses the merits versus off-the-shelf cyclic dinucleotide (CDN) delivery techniques in both the brilliant tissue-homing capacity, even across the intractable blood-brain barrier (BBB), and the desired cytosolic entry for enhanced STING-activating signaling. The improved antigen-presentation performance with this nanovaccine-driven STING activation further enhances tumor-specific T-cell immunoresponse. Thus, DT-Exo-STING reverses immunosuppressive glioblastoma microenvironments to pro-inflammatory, tumoricidal states, leading to an almost obliteration of intracranial primary lesions. Significantly, an upscaling option that harnesses autologous tumor tissues for personalized DT-Exo-STING vaccines increases sensitivity to immune checkpoint blockade (ICB) therapy and exerts systemic immune memory against post-operative glioma recrudesce. These findings represent an emerging method for glioblastoma immunotherapy, warranting further exploratory development in the clinical realm.

Fused-Ring Pyrrole-Based Near-Infrared Emissive Organic RTP Material for Persistent Afterglow Bioimaging

Organic near-infrared room temperature phosphorescence (RTP) materials offer remarkable advantages in bioimaging due to their characteristic time scales and background noise elimination. However, developing near-infrared RTP materials for deep tissue imaging still faces challenges since the small band gap may increase the non-radiative decay, resulting in weak emission and short phosphorescence lifetime. In this study, fused-ring pyrrole-based structures were employed as the guest molecules for the construction of long wavelength emissive RTP materials. Compared to the decrease of the singlet energy level, the triplet energy level showed a more effectively decrease with the increase of the conjugation of the substituent groups. Moreover, the sufficient conjugation of fused ring structures in the guest molecule suppresses the non-radiative decay of triplet excitons. Therefore, a near-infrared RTP material (764 nm) was achieved for deep penetration bioimaging. Tumor cell membrane is used to coat RTP nanoparticles (NPs) to avoid decreasing the RTP performance compared to traditional coating by amphiphilic surfactants. RTP NPs with tumor-targeting properties show favorable phosphorescent properties, superior stability, and excellent biocompatibility. These NPs are applied for time-resolved luminescence imaging to eliminate background interference with excellent tissue penetration. This study provides a practical solution to prepare long-wavelength and long-lifetime organic RTP materials and their applications in bioimaging.

Cell-Based Micro/Nano-Robots for Biomedical Applications: A Review

Micro/nano-robots are powerful tools for biomedical applications and are applied in disease diagnosis, tumor imaging, drug delivery, and targeted therapy. Among the various types of micro-robots, cell-based micro-robots exhibit unique properties because of their different cell sources. In combination with various actuation methods, particularly externally propelled methods, cell-based microrobots have enormous potential for biomedical applications. This review introduces recent progress and applications of cell-based micro/nano-robots. Different actuation methods for micro/nano-robots are summarized, and cell-based micro-robots with different cell templates are introduced. Furthermore, the review focuses on the combination of cell-based micro/nano-robots with precise control using different external fields. Potential challenges, further prospects, and clinical translations are also discussed.

Lipid-Centric Design of Plasma Membrane-Mimicking Nanocarriers for Targeted Chemotherapeutic Delivery

The plasma membranes (PM) of mammalian cells contain diverse lipids, proteins, and carbohydrates that are important for systemic recognition and communication in health and disease. Cell membrane coating technology that imparts unique properties of natural plasma membranes to the surface of encapsulated nanoparticles is thus becoming a powerful platform for drug delivery, immunomodulation, and vaccination. However, current coating methods fail to take full advantage of the natural systems because they disrupt the complex and functionally essential features of PMs, most notably the chemical diversity and compositional differences of lipids in two leaflets of the PM. Herein, a new lipid coating approach is reported in which the lipid composition is optimized through a combination of biomimetic and systematic variation approaches for the custom design of nanocarrier systems for precision drug delivery. Nanocarriers coated with the optimized lipids offer unique advantages in terms of bioavailability and efficiency in tumor targeting, tumor penetration, cellular uptake, and drug release. This pilot study provides new insight into the rational design and optimization of nanocarriers for cancer chemotherapeutic drugs and lays the foundation for further customization of cell membrane-mimicking nanocarriers through systematic incorporation of other components.

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.

Advanced Generation Therapeutics: Biomimetic Nanodelivery System for Tumor Immunotherapy

Tumor immunotherapy is a safe and effective strategy for precision medicine. However, immunotherapy for most cancer cases still ends in failure, with the root causes of the immunosuppressive and extraordinary heterogeneity of the solid tumors microenvironment. The emerging biomimetic nanodelivery system provides a promising tactic to improve the immunotherapy effect while reducing the adverse reactions on nontarget cells. Herein, we summarize the relationship between tumor occurrence and tumor immune microenvironment, mechanism of tumor immune escape, immunotherapy classification (including adoptive cellular therapy, cytokines, cancer vaccines, and immune checkpoint inhibitors) and recommend target cells for immunotherapy first, and then emphatically introduce the recent advances and applications of the latest biomimetic nanodelivery systems (e.g., immune cells, erythrocytes, tumor cells, platelets, bacteria) in tumor immunotherapy. Meanwhile, we separately summarize the application of tumor vaccines. Finally, the predictable challenges and perspectives in a forward exploration of biomimetic nanodelivery systems for tumor immunotherapy are also discussed.

Cellular-Membrane-Derived Vesicles for Cancer Immunotherapy

The medical community is constantly searching for new and innovative ways to treat cancer, and cellular-membrane-derived artificial vesicles are emerging as a promising avenue for cancer immunotherapy. These vesicles, which are derived from mammal and bacteria cell membranes, offer a range of benefits, including compatibility with living organisms, minimal immune response, and prolonged circulation. By modifying their surface, manipulating their genes, combining them with other substances, stimulating them externally, and even enclosing drugs within them, cellular vesicles have the potential to be a powerful tool in fighting cancer. The ability to merge drugs with diverse compositions and functionalities in a localized area is particularly exciting, as it offers a way to combine different immunotherapy treatments for maximum impact. This review contains information on the various sources of these vesicles and discusses some recent developments in cancer immunotherapy using this promising technology. While there are still obstacles to overcome, the possibilities for cellular vesicles in cancer treatment are truly exciting.

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.

Creation of a High-Throughput Microfluidic Platform for Single-Cell Transcriptome Sequencing of Cell-Cell Interactions

Cell-cell interaction is one of the major modalities for transmitting information between cells and activating the effects of functional cells. However, the construction of high-throughput analysis technologies from cell omics focusing on the impact of interactions of functional cells on targets has been relatively unexplored. Here, they propose a droplet-based microfluidic platform for cell-cell interaction sequencing (c-c-seq) and screening in vitro to address this challenge. A class of interacting cells is pre-labeled using cell molecular tags, and additional single-cell sequencing reagents are introduced to quickly form functional droplet mixes. Lastly, gene expression analysis is used to deduce the impact of the interaction, while molecular sequence tracing identifies the type of interaction. Research into the active effect between antigen-presenting cells and T cells, one of the most common cell-to-cell interactions, is crucial for the advancement of cancer therapy, particularly T cell receptor-engineered T cell therapy. As it allows for high throughput, this platform is superior to well plates as a research platform for cell-to-cell interactions. When combined with the next generation of sequencing, the platform may be able to more accurately evaluate interactions between epitopes and receptors and verify their functional relevance.

Dendritic Cell-Mimicking Nanoparticles Promote mRNA Delivery to Lymphoid Organs

Spleen and lymphoid organs are important targets for messenger RNA (mRNA) delivery in various applications. Current nanoparticle delivery methods rely on drainage to lymph nodes from intramuscular or subcutaneous injections. In difficult-to-transfect antigen-presenting cells (APCs), such as dendritic cells (DCs), effective mRNA transfection remains a significant challenge. In this study, a lymphatic targeting carrier using DC membranes is developed, that efficiently migrated to lymphoid organs, such as the spleen and lymph nodes. The nanoparticles contained an ionizable lipid (YK009), which ensured a high encapsulation efficacy of mRNA and assisted mRNA with endosomal escape after cellular uptake. Dendritic cell-mimicking nanoparticles (DCMNPs) showed efficient protein expression in both the spleen and lymph nodes after intramuscular injections. Moreover, in immunized mice, DCMNP vaccination elicited Spike-specific IgG antibodies, neutralizing antibodies, and Th1-biased SARS-CoV-2-specific cellular immunity. This work presents a powerful vaccine formula using DCMNPs, which represents a promising vaccine candidate for further research and development.

Targeted siRNA Delivery by Bioinspired Cancer Cell Membrane-Coated Nanoparticles with Enhanced Anti-Cancer Immunity

Introduction

Cell-membrane nanocarriers are usually constructed by modifying the nanoparticle surface with cell membrane extracts, which has a direct benefit in endowing targeting capacity to nanocarriers based on their original cell types. However, delivering nucleic acid cargos by cell membrane-based nanoparticles is difficult owing to the strong negative charge of the cell membrane fraction. In this study, we developed a cancer cell membrane-based drug delivery system, the cMDS, for efficient siRNA delivery. Meanwhile, the cancer-specific immune response stimulated by the gene vector itself could offer synergistic anti-cancer ability.

Methods

The cMDS was prepared by ultrasound, and its transfection efficiency and anti-cancer ability were examined using cultures of CT26 cells. MTT and red blood cell hemolysis tests were performed to assess the safety of cMDS, while its targeted gene delivery and strong immune stimulation were investigated in a subcutaneous tumor model. Moreover, the detailed anti-cancer immune stimulation mechanisms of cMDS are uncovered by protein chip analysis.

Results

The cMDS was spherical core-shell structure. It showed high transfection efficiency and anti-cancer ability in vitro. In animal experiments, intravenously administered cMDS/siStat3 complex efficiently suppress the growth of colon cancer. Moreover, the result of protein chip analysis suggested that cMDS affect the migration and chemotaxis of immune cells.

Conclusion

The cMDS shows obvious tumor tissue-specific accumulation properties and strong immune stimulation ability. It is an advanced targeted gene delivery system with potent immunotherapeutic properties.

A single-shot prophylactic tumor vaccine enabled by an injectable biomembrane hydrogel

Prophylactic tumor vaccines hold great promise against tumor occurrence. However, their clinical efficacy remains low due to inadequate activation of strong-sustainable immunity. Herein, a biomembrane hydrogel was designed as a powerful single-shot prophylactic tumor vaccine. Mannose-decorated hybrid biomembrane (MHCM) modified with oxidized sodium alginate (OSA) was designed as a gelator (O-MHCM), where the hybrid biomembrane (HCM) is a hybridization of bacterial outer membrane vesicles (OMV) and tumor cell membranes (TCM). The O-MHCM enables quick gelation subcutaneously where the cysteine protease inhibitor E64 is encapsulated in hydrogel micropores. After a single vaccination of E64@O-MHCM hydrogel, MHCM and E64 are released sustainably due to OSA moiety degradation. The MHCM enables active targeting to dendritic cells (DC) and effective DC maturation. Meanwhile, the E64 enables sufficient antigen availability for subsequent cross presentation. Ultimately, strong and sustainable T lymphocyte-mediated immunity was elicited, demonstrating a strong prophylactic effect against breast tumors. This study provides a long-lasting platform to prevent tumor occurrence, opening an innovative avenue for the design of a single-shot prophylactic tumor vaccine. STATEMENT OF SIGNIFICANCE: Developing a single-shot prophylactic tumor vaccine to elicit strong-sustainable immunity is of great interest clinically. Here, a prophylactic tumor vaccine was designed using an injectable biomembrane hydrogel for achieving strong-sustainable immunity. The mannose-tailored hybrid biomembrane was modified with oxidized sodium alginate to result in a gelator, which enabled the formation of the hydrogel after subcutaneous injection. Cysteine protease inhibitor E64 was incorporated into the micropores of the hydrogel. The hydrogel induced strong-sustainable immunity through the continuous release of active components. This was facilitated by the mannose moiety, which enabled active targeting, as well as the antigen and adjuvant function of biomembrane, and the E64-enabled suppression of antigen degradation. The biomembrane hydrogel demonstrated powerful prevention of 4T1 breast tumors. This study offers an attractive strategy for designing a single-shot prophylactic tumor vaccine.

Cancer Cell Membrane Nanodiscs for Antitumor Vaccination

Cell membrane-based nanovaccines have demonstrated attractive features due to their inherently multiantigenic nature and ability to be formulated with adjuvants. Here, we report on cellular nanodiscs fabricated from cancer cell membranes and incorporated with a lipid-based adjuvant for antitumor vaccination. The cellular nanodiscs, with their small size and discoidal shape, are readily taken up by antigen-presenting cells and drain efficiently to the lymph nodes. Due to its highly immunostimulatory properties, the nanodisc vaccine effectively stimulates the immune system and promotes tumor-specific immunity. Using a murine colorectal cancer model, strong control of tumor growth is achieved in both prophylactic and therapeutic settings, particularly in combination with checkpoint blockades. Considerable therapeutic efficacy is also observed in treating a weakly immunogenic metastatic melanoma model. This work presents a new paradigm for the design of multiantigenic nanovaccines that can effectively activate antitumor immune responses and may be applicable to a wide range of cancers.

Exploiting immunostimulatory mechanisms of immunogenic cell death to develop membrane-encapsulated nanoparticles as a potent tumor vaccine

Vaccine is one of the most promising strategies for cancer immunotherapy; however, there are no therapeutic cancer vaccine achieving significant clinical efficacy till now. The main limiting factors include the immune suppression and escape mechanisms developed by tumor and not enough capacity of vaccines to induce a vigorous anti-tumor immunity. This study aimed to develop a strategy of membrane-based biomimetic nanovaccine and investigate the immunological outcomes of utilizing the unique immunostimulatory mechanisms derived of immunogenic cell death (ICD) and of fulfilling a simultaneous nanoscale delivery of a highlighted tumor antigen and broad membrane-associated tumor antigens in the vaccine design. TC-1 tumor cells were treated in vitro with a mixture of mitoxantrone and curcumin for ICD induction, and then chitosan (CS)-coated polylactic co-glycolic acid (PLGA) nanoparticles loaded with HPV16 E744-62 peptides were decorated with the prepared ICD tumor cell membrane (IM); further, the IM-decorated nanoparticles along with adenosine triphosphate (ATP) were embedded with sodium alginate (ALG) hydrogel, And then, the immunological features and therapeutic potency were evaluated in vitro and in vivo. The nanovaccine significantly stimulated the migration, antigen uptake, and maturation of DCs in vitro, improved antigen lysosome escape, and promoted the retention at injection site and accumulation in LNs of the tumor antigen in vivo. In a subcutaneously grafted TC-1 tumor model, the therapeutic immunization of nanovaccine elicited a dramatical antitumor immunity. This study provides a strategy for the development of tumor vaccines.

Fused Cytomembrane-Camouflaged Nanoparticles for Tumor-Specific Immunotherapy

Tumor immunotherapy is commonly hindered by inefficient delivery and presentation of tumor antigens as well as immunosuppressive tumor microenvironment. To overcome these barriers, a tumor-specific nanovaccine capable of delivering tumor antigens and adjuvants to antigen-presenting cells and modulating the immune microenvironment to elicit strong antitumor immunity is reported. This nanovaccine, named FCM@4RM, is designed by coating the nanocore (FCM) with a bioreconstituted cytomembrane (4RM). The 4RM, which is derived from fused cells of tumorous 4T1 cells and RAW264.7 macrophages, enables effective antigen presentation and stimulation of effector T cells. FCM is self-assembled from Fe(II), unmethylated cytosine-phosphate-guanine oligodeoxynucleotide (CpG), and metformin (MET). CpG, as the stimulator of toll-like receptor 9, induces the production of pro-inflammatory cytokine and the maturation of cytotoxic T lymphocytes (CTLs), thereby enhancing antitumor immunity. Meanwhile, MET functions as the programmed cell death ligand 1 inhibitor and can restore the immune responses of T cells against tumor cells. Therefore, FCM@4RM exhibits high targeting capabilities toward homologous tumors that develop from 4T1 cells. This work offers a paradigm for developing a nanovaccine that systematically regulates multiple immune-related processes to achieve optimal antitumor immunotherapy.

Biomembrane nanostructures: Multifunctional platform to enhance tumor chemoimmunotherapy via effective drug delivery

Chemotherapeutic drugs have been found to activate the immune response against tumors by inducing immunogenic cell death, in addition to their direct cytotoxic effects toward tumors, therefore broadening the application of chemotherapy in tumor immunotherapy. The combination of other therapeutic strategies, such as phototherapy or radiotherapy, could further strengthen the therapeutic effects of immunotherapy. Nanostructures can facilitate multimodal tumor therapy by integrating various active agents and combining multiple types of therapeutics in a single nanostructure. Biomembrane nanostructures (e.g., exosomes and cell membrane-derived nanostructures), characterized by superior biocompatibility, intrinsic targeting ability, intelligent responsiveness and immune-modulating properties, could realize superior chemoimmunotherapy and represent next-generation nanostructures for tumor immunotherapy. This review summarizes recent advances in biomembrane nanostructures in tumor chemoimmunotherapy and highlights different types of engineering approaches and therapeutic mechanisms. A series of engineering strategies for combining different biomembrane nanostructures, including liposomes, exosomes, cell membranes and bacterial membranes, are summarized. The combination strategy can greatly enhance the targeting, intelligence and functionality of biomembrane nanostructures for chemoimmunotherapy, thereby serving as a stronger tumor therapeutic method. The challenges associated with the clinical translation of biomembrane nanostructures for chemoimmunotherapy and their future perspectives are also discussed.

Universal Fe/Mn Nanoadjuvant with T1/T2 MRI Self-Navigation and Gas Generation for Ideal Vaccines with Precise Tracking

Because of the distinguished properties between nanovaccine and traditional vaccine, the precise guidelines for nanovaccines with an optimal vaccination strategy to induce ideal immunities are greatly desired for combating major diseases, including cancer and infections. Herein, we designed and synthesized a self-navigating nanoadjuvant composed of Fe-doped manganese carbonate and its nanovaccine via a facile method. First, the degradation of the nanoadjuvant under acidic milieu of immune cells in lymph nodes would generate T1 and T2 MR imaging (MRI) signals to reflect the transformation dynamics of the nanovaccine and inform us when the next vaccination needed. Under this guideline, nanovaccines with a precise vaccination strategy triggered robust antigen-specific immune responses and immunological memory to effectively prevent ovalbumin (OVA)-expressing melanoma relapse by activating dendritic cells via a stimulator of interferon genes (STING) signaling pathway and inducing antigen cross-presentation by shaping lysosome integrity with CO2 generation and upregulating transporter associated antigen processing 1 (TAP-1) transporter. This study provides a universal nanoadjuvant with imaging self-guidance, immunopotentiating, and cross-priming activities for developing precise vaccines with an optimal immunization strategy to combat major diseases.

Ferroptosis and Necroptosis Produced Autologous Tumor Cell Lysates Co-Delivering with Combined Immnoadjuvants as Personalized In Situ Nanovaccines for Antitumor Immunity

Nanovaccine-based immunotherapy has been considered as a major pillar to stimulate the host immune system to recognize and eradicate tumor cells as well as establish a long-term immune memory to prevent tumor relapse and metastasis. However, the weak specificity and low cross-presentation of antigens, as well as the immunosuppressive microenvironments of tumor tissues, are still the major obstacles on exerting the therapeutic performance of tumor nanovaccines sufficiently. Herein, we design and construct cytosine guanine dinucleotide (CpG) oligodeoxynucleotide (ODN)-loaded aluminum hydroxyphosphate nanoparticles covered by Fe-Shikonin metal-phenolic networks (MPNs) (Alum-CpG@Fe-Shikonin NPs) as personalized in situ nanovaccines for antitumor immunity. Upon internalization by tumor cells, the shell of Fe-Shikonin MPNs will disassemble into Fe2+ and Shikonin to elicit the immunogenic cell death of tumor cells through ferroptosis and necroptosis. Then, dying tumor cell-released autologous tumor cell lysates will be absorbed by Alum NPs and codelivered with CpG ODN to professional antigen-presenting cells temporally and spatially to activate multistep cascade antitumor immune responses, including dendritic cell maturation, antigen cross-presentation, natural killer cell and cytotoxic T lymphocyte infiltrations, and tumor-associated macrophage repolarization. Benefiting from the synergistic effects of Alum NPs, CpG ODN, and Fe-Shikonin MPNs, our Alum-CpG@Fe-Shikonin NPs exhibit drastic cytotoxicity and accurate selectivity on eradicating primary tumor, strong abscopal effect on inhibiting distant tumor, and a long-term immune memory effect on preventing tumor metastasis and recurrence. Because our report provides a feasible strategy to in situ make full use of autologous tumor cell lysates, which present an entire spectrum of the patient's personal epitopes without complicated ex vivo processes, such as extraction, purification, and sequencing, it may promote the development of personalized nanovaccines for antitumor immunity.

Advanced subunit vaccine delivery technologies: From vaccine cascade obstacles to design strategies

Designing and manufacturing safe and effective vaccines is a crucial challenge for human health worldwide. Research on adjuvant-based subunit vaccines is increasingly being explored to meet clinical needs. Nevertheless, the adaptive immune responses of subunit vaccines are still unfavorable, which may partially be attributed to the immune cascade obstacles and unsatisfactory vaccine design. An extended understanding of the crosstalk between vaccine delivery strategies and immunological mechanisms could provide scientific insight to optimize antigen delivery and improve vaccination efficacy. In this review, we summarized the advanced subunit vaccine delivery technologies from the perspective of vaccine cascade obstacles after administration. The engineered subunit vaccines with lymph node and specific cell targeting ability, antigen cross-presentation, T cell activation properties, and tailorable antigen release patterns may achieve effective immune protection with high precision, efficiency, and stability. We hope this review can provide rational design principles and inspire the exploitation of future subunit vaccines.

Intelligent nanomaterials for cancer therapy: recent progresses and future possibilities

Intelligent nanomedicine is currently one of the most active frontiers in cancer therapy development. Empowered by the recent progresses of nanobiotechnology, a new generation of multifunctional nanotherapeutics and imaging platforms has remarkably improved our capability to cope with the highly heterogeneous and complicated nature of cancer. With rationally designed multifunctionality and programmable assembly of functional subunits, the in vivo behaviors of intelligent nanosystems have become increasingly tunable, making them more efficient in performing sophisticated actions in physiological and pathological microenvironments. In recent years, intelligent nanomaterial-based theranostic platforms have showed great potential in tumor-targeted delivery, biological barrier circumvention, multi-responsive tumor sensing and drug release, as well as convergence with precise medication approaches such as personalized tumor vaccines. On the other hand, the increasing system complexity of anti-cancer nanomedicines also pose significant challenges in characterization, monitoring and clinical use, requesting a more comprehensive and dynamic understanding of nano-bio interactions. This review aims to briefly summarize the recent progresses achieved by intelligent nanomaterials in tumor-targeted drug delivery, tumor immunotherapy and temporospatially specific tumor imaging, as well as important advances of our knowledge on their interaction with biological systems. In the perspective of clinical translation, we have further discussed the major possibilities provided by disease-oriented development of anti-cancer nanomaterials, highlighting the critical importance clinically-oriented system design.

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.

Nanovaccine-based strategies for lymph node targeted delivery and imaging in tumor immunotherapy

Therapeutic tumor vaccines have attracted considerable attention in the past decade; they can induce tumor regression, eradicate minimal residual disease, establish lasting immune memory and avoid non-specific and adverse side effects. However, the challenge in the field of therapeutic tumor vaccines is ensuring the delivery of immune components to the lymph nodes (LNs) to activate immune cells. The clinical response rate of traditional therapeutic tumor vaccines falls short of expectations due to inadequate lymph node delivery. With the rapid development of nanotechnology, a large number of nanoplatform-based LN-targeting nanovaccines have been exploited for optimizing tumor immunotherapies. In addition, some nanovaccines possess non-invasive visualization performance, which is benefit for understanding the kinetics of nanovaccine exposure in LNs. Herein, we present the parameters of nanoplatforms, such as size, surface modification, shape, and deformability, which affect the LN-targeting functions of nanovaccines. The recent advances in nanoplatforms with different components promoting LN-targeting are also summarized. Furthermore, emerging LNs-targeting nanoplatform-mediated imaging strategies to both improve targeting performance and enhance the quality of LN imaging are discussed. Finally, we summarize the prospects and challenges of nanoplatform-based LN-targeting and /or imaging strategies, which optimize the clinical efficacy of nanovaccines in tumor immunotherapies.

Advances in PD-1 signaling inhibition-based nano-delivery systems for tumor therapy

In recent years, cancer immunotherapy has emerged as an exciting cancer treatment. Immune checkpoint blockade brings new opportunities for more researchers and clinicians. Programmed cell death receptor-1 (PD-1) is a widely studied immune checkpoint, and PD-1 blockade therapy has shown promising results in a variety of tumors, including melanoma, non-small cell lung cancer and renal cell carcinoma, which greatly improves patient overall survival and becomes a promising tool for the eradication of metastatic or inoperable tumors. However, low responsiveness and immune-related adverse effects currently limit its clinical application. Overcoming these difficulties is a major challenge to improve PD-1 blockade therapies. Nanomaterials have unique properties that enable targeted drug delivery, combination therapy through multidrug co-delivery strategies, and controlled drug release through sensitive bonds construction. In recent years, combining nanomaterials with PD-1 blockade therapy to construct novel single-drug-based or combination therapy-based nano-delivery systems has become an effective mean to address the limitations of PD-1 blockade therapy. In this study, the application of nanomaterial carriers in individual delivery of PD-1 inhibitors, combined delivery of PD-1 inhibitors and other immunomodulators, chemotherapeutic drugs, photothermal reagents were reviewed, which provides effective references for designing new PD-1 blockade therapeutic strategies.

Biomimetic Cell-Derived Nanoparticles: Emerging Platforms for Cancer Immunotherapy

Cancer immunotherapy can significantly prevent tumor growth and metastasis by activating the autoimmune system without destroying normal cells. Although cancer immunotherapy has made some achievements in clinical cancer treatment, it is still restricted by systemic immunotoxicity, immune cell dysfunction, cancer heterogeneity, and the immunosuppressive tumor microenvironment (ITME). Biomimetic cell-derived nanoparticles are attracting considerable interest due to their better biocompatibility and lower immunogenicity. Moreover, biomimetic cell-derived nanoparticles can achieve different preferred biological effects due to their inherent abundant source cell-relevant functions. This review summarizes the latest developments in biomimetic cell-derived nanoparticles for cancer immunotherapy, discusses the applications of each biomimetic system in cancer immunotherapy, and analyzes the challenges for clinical transformation.

"Bioinspired" Membrane-Coated Nanosystems in Cancer Theranostics: A Comprehensive Review

Achieving precise cancer theranostics necessitates the rational design of smart nanosystems that ensure high biological safety and minimize non-specific interactions with normal tissues. In this regard, "bioinspired" membrane-coated nanosystems have emerged as a promising approach, providing a versatile platform for the development of next-generation smart nanosystems. This review article presents an in-depth investigation into the potential of these nanosystems for targeted cancer theranostics, encompassing key aspects such as cell membrane sources, isolation techniques, nanoparticle core selection, approaches for coating nanoparticle cores with the cell membrane, and characterization methods. Moreover, this review underscores strategies employed to enhance the multi-functionality of these nanosystems, including lipid insertion, membrane hybridization, metabolic engineering, and genetic modification. Additionally, the applications of these bioinspired nanosystems in cancer diagnosis and therapeutics are discussed, along with the recent advances in this field. Through a comprehensive exploration of membrane-coated nanosystems, this review provides valuable insights into their potential for precise cancer theranostics.

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.