Nanotechnology-empowered vaccine delivery for enhancing CD8+ T cells-mediated cellular immunity

Dendritic cell-based biomimetic nanoparticles for foot-and-mouth disease induce robust cellular immunity

Foot-and-mouth disease (FMD) is a highly contagious and economically devastating viral disease of ruminants and swine, badly affecting the livestock industry worldwide. In clinical practice, vaccination is a frequently employed strategy to prevent foot-and-mouth disease (FMDV). However, commercial inactivated vaccines for FMD mainly rely on humoral immunity, exhibiting poor cellular immune responses and causing adverse reactions. Here, we use the double emulsion method to prepare poly (lactic-co-glycolic acid) nanoparticles (PLGA-NP) encapsulated with IL-2 cytokines, wrap the dendritic cell (DC) membrane carrying FMDV antigen information on the surface of the nanoparticles, obtaining a biomimetic nanoparticle vaccine Biom@DC with uniform size. This vaccine can effortlessly move through lymph nodes due to its nanoscale size advantage. It also possesses DC ability to present antigens, and antigen presentation can be made more effective with high biocompatibility. The sustained release of IL-2 encapsulated in the core of PLGA-NP in vivo can effectively promote the body's cellular immune response. Immune tests on mice have shown that Biom@DC may greatly increase T cell activation and proliferation both in vivo and in vitro, while also significantly reducing the fraction of inhibitory Treg cells. Furthermore, in the micro serum neutralization assay for FMDV, it has been demonstrated that the group vaccinated with Biom@DC exhibits a clear neutralizing effect. Given its strong immunogenicity, Biom@DC has the potential to develop into a novel, potent anti-FMDV vaccination.

Nanotechnology in Advancing Chimeric Antigen Receptor T Cell Therapy for Cancer Treatment

Chimeric antigen receptor (CAR) T cell therapy has emerged as a groundbreaking treatment for hematological cancers, yet it faces significant hurdles, particularly regarding its efficacy in solid tumors and concerning associated adverse effects. This review provides a comprehensive analysis of the advancements and ongoing challenges in CAR-T therapy. We highlight the transformative potential of nanotechnology in enhancing CAR-T therapy by improving targeting precision, modulating the immune-suppressive tumor microenvironment, and overcoming physical barriers. Nanotechnology facilitates efficient CAR gene delivery into T cells, boosting transfection efficiency and potentially reducing therapy costs. Moreover, nanotechnology offers innovative solutions to mitigate cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). Cutting-edge nanotechnology platforms for real-time monitoring of CAR-T cell activity and cytokine release are also discussed. By integrating these advancements, we aim to provide valuable insights and pave the way for the next generation of CAR-T cell therapies to overcome current limitations and enhance therapeutic outcomes.

Chiral Intranasal Nanovaccines as Antivirals for Respiratory Syncytial Virus

This study aimed to develop an intranasal nanovaccine by combining chiral nanoparticles with the RSV pre-fusion protein (RSV protein) to create L-nanovaccine (L-Vac). The results showed that L-NPs increased antigen attachment in the nasal cavity by 3.83 times and prolonged its retention time to 72 h. In vivo experimental data demonstrated that the intranasal immunization with L-Vac induced a 4.86-fold increase in secretory immunoglobulin A (sIgA) secretion in the upper respiratory tract, a 1.85-fold increase in the lower respiratory tract, and a 20.61-fold increase in RSV-specific immunoglobin G (IgG) titer levels in serum, compared with the commercial Alum Vac, while the neutralizing activity against the RSV authentic virus is 1.66-fold higher. The mechanistic investigation revealed that L-Vac activated the tumor necrosis factor (TNF) signaling pathway in nasal epithelial cells (NECs), in turn increasing the expression levels of interleukin-6 (IL-6) and C-C motif chemokine ligand 20 (CCL20) by 1.67-fold and 3.46-fold, respectively, through the downstream nuclear factor kappa-B (NF-κB) signaling pathway. Meanwhile, CCL20 recruited dendritic cells (DCs) and L-Vac activated the Toll-like receptor signaling pathway in DCs, promoting IL-6 expression and DCs maturation, and boosted sIgA production and T-cell responses. The findings suggested that L- Vac may serve as a candidate for the development of intranasal medicine against various types of respiratory infections.

Mannan-Decorated Lipid Calcium Phosphate Nanoparticle Vaccine Increased the Antitumor Immune Response by Modulating the Tumor Microenvironment

With the rapid development of tumor immunotherapy, nanoparticle vaccines have attracted much attention as potential therapeutic strategies. A systematic review and analysis must be carried out to investigate the effect of mannose modification on the immune response to nanoparticles in regulating the tumor microenvironment, as well as to explore its potential clinical application in tumor therapy. Despite the potential advantages of nanoparticle vaccines in immunotherapy, achieving an effective immune response in the tumor microenvironment remains a challenge. Tumor immune escape and the overexpression of immunosuppressive factors limit its clinical application. Therefore, our review explored how to intervene in the immunosuppressive mechanism in the tumor microenvironment through the use of mannan-decorated lipid calcium phosphate nanoparticle vaccines to improve the efficacy of immunotherapy in patients with tumors and to provide new ideas and strategies for the field of tumor therapy.

Ultrasound-Activatable In Situ Vaccine for Enhanced Antigen Self- and Cross-Presentation to Overcome Cancer Immunotherapy Resistance

Insufficient antigen self-presentation of tumor cells and ineffective antigen cross-presentation by dendritic cells (DCs) contribute to diminished immune recognition and activation, which cause resistance to immunotherapies. Herein, we present an ultrasound-activatable in situ vaccine by utilizing a hybrid nanovesicle composed of a thylakoid (TK)/platelet (PLT) membrane and a liposome encapsulating DNA methyltransferase inhibitor zebularine (Zeb) and sonosensitizer hematoporphyrin monomethyl ether (HMME). Upon local exposure to ultrasound, reactive oxygen species (ROS) are generated and induce the sequential release of the payloads. Zeb can efficiently inhibit tumor DNA hypermethylation, promoting major histocompatibility complex class I (MHC-I) molecules-mediated antigen self-presentation to improve immune recognition. Meanwhile, the catalase on the TK membrane can decompose the tumoral overexpressed H2O2 into O2, which boosts the generation of ROS and the destruction of tumor cells, resulting in the in situ antigen release and cross-presentation of tumor antigens by DCs. This in situ vaccine simultaneously promotes antigen self-presentation and cross-presentation, resulting in heightened antitumor immunity to overcome resistance.

Virus-Mimetic Extracellular-Vesicle Vaccine Boosts Systemic and Mucosal Immunity via Immune Recruitment

Mucosal vaccines can prevent viruses from infecting the respiratory mucosa, rather than only curtailing infection and protecting against the development of disease symptoms. The SARS-CoV-2 spike receptor-binding domain (RBD) is a compelling vaccine target but is undermined by suboptimal mucosal immunogenicity. Here, we report a SARS-CoV-2-mimetic extracellular-vesicle vaccine developed using genetic engineering and dendritic cell membrane budding. After mucosal immunization, the vaccine recruits antigen-presenting cells rapidly initiating a strong innate immune response. Notably, it obviates the need for adjuvants and can induce germinal center formation through both intramuscular and intratracheal vaccination. It not only elicits high levels of RBD-specific antibodies but also stimulates extensive cellular immunity in the respiratory mucosa. A sequential immunization strategy, starting with an intramuscular injection followed by an intratracheal booster, significantly bolsters mucosal immunity with high levels of IgA and tissue-resident memory T cell responses, thereby establishing a formidable defense against pseudovirus infection.

Administration sequence- and formation-dependent vaccination using acid-degradable polymeric nanoparticles with high antigen encapsulation capability

Vaccines aim to efficiently and specifically activate the immune system via a cascade of antigen uptake, processing, and presentation by antigen-presenting cells (APCs) to CD4 and CD8 T cells, which in turn drive humoral and cellular immune responses. The specific formulation of vaccine carriers can not only shield the antigens from premature sequestering before reaching APCs but also favorably promote intracellular antigen presentation and processing. This study compares two different acid-degradable polymeric nanoparticles that are capable of encapsulating a moderately immunogenic antigen, GFP, at nearly full efficacy via electrostatic interactions or molecular affinity between His tag and Ni-NTA-conjugated monomners. This resulted in GFP-encapsulating NPs composed of ketal monomers and crosslinkers (KMX/GFP NPs) and NTA-conjugated ketal monomers and crosslinkers (NKMX/GFP NPs), respectively. Encapsulated GFP was found to be released more rapidly from NKMX/GFP NPs (electrostatic encapsulation) than from KMX/GFP NPs (affinity-driven encapsulation). In vivo vaccination studies demonstrated that while repeated injections of either NP formulation resulted in poorer generation of anti-GFP antibodies than injections of the GFP antigen itself, sequential injections of NPs and GFP as prime and booster vaccines, respectively, restored the humoral response. We proposed that NPs primarily assist APCs in antigen presentation by T cells, and B cells need to be further stimulated by free protein antigens to produce antibodies. The findings of this study suggest that the immune response can be modulated by varying the chemistry of vaccine carriers and the sequences of vaccination with free antigens and antigen-encapsulating NPs.

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.

Boosting humoral and cellular immunity with enhanced STING activation by hierarchical mesoporous metal-organic framework adjuvants

Vaccination is essential for preventing and controlling infectious diseases, along with reducing mortality. Developing safe and versatile adjuvants to enhance humoral and cellular immune responses to vaccines remains a key challenge in vaccine development. Here, we designed hierarchical mesoporous MOF-801 (HM801) using a Cocamidopropyl betaine (CAPB) and a Pluronics F127 in an aqueous phase system. Meanwhile, we synthesized a novel SARS-CoV-2 nanovaccine (R@M@HM801) with a high loading capacity for both the STING agonist (MSA-2) and the Delta receptor binding domain (Delta-RBD) antigen. R@M@HM801 enhanced MSA-2 and RBD utilization and effectively co-delivered MSA-2 and RBD antigens to antigen-presenting cells in the draining lymph nodes, thereby promoting the activation of both T and B cells. Lymphocyte single-cell analysis showed that R@M@HM801 stimulated robust CD11b+CD4+ T cells, CXCR5+CD4+ T follicular helper (Tfh), and durable CD4+CD44+CD62L-, CD8+CD44+CD62L- effector memory T cell (TEM) immune responses, and promoted the proliferative activation of CD26+ B cells in vivo. Meanwhile, R@M@HM801 induced stronger specific antibodies and neutralization of pseudovirus against Delta compared to the RBD + MAS-2 and RBD + MAS-2 + Alum vaccines. Our study demonstrated the efficacy of a hierarchical mesoporous HM801 and its potential immune activation mechanism in enhancing adaptive immune responses against viruses and other diseases.

Therapeutic potential of CRISPR/CAS9 genome modification in T cell-based immunotherapy of cancer

Today, genome editing technologies like zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and clustered regularly interspaced short palindromic repeats (CRISPR) are being used in clinical trials and the treatment of diseases like acquired immunodeficiency syndrome (AIDS) and cancer. CRISPR stands out as one of the most advanced tools for genome editing due to its simplicity and cost-effectiveness. It can selectively modify specific locations in the genome, offering new possibilities for treating human diseases. The CRISPR system uses ribonucleic acid-deoxyribonucleic acid (RNA-DNA) recognition to combat infections, regulate gene expression, and treat cancer. Chimeric antigen receptor (CAR) T-cell therapy, which uses T lymphocytes to eliminate cancer cells, can be improved by combining it with CRISPR technology. However, there are challenges in using CAR-T cells, including a lack of quantity and quality, exhaustion, neurotoxicity, cytokine release syndrome (CRS), B cell aplasia, tumor lysis syndrome, and anaphylaxis. Preclinical studies on CRISPR-edited CAR-T cells show promising results and targeting detrimental regulatory genes can enhance cancer treatment in the future.

Self-adjuvanting polymeric nanovaccines enhance IFN production and cytotoxic T cell response

Vaccines represent one of the most powerful and cost-effective innovations for controlling a wide range of infectious diseases caused by various viruses and bacteria. Unlike mRNA and DNA-based vaccines, subunit vaccines carry no risk of insertional mutagenesis and can be lyophilized for convenient transportation and long-term storage. However, existing adjuvants are often associated with toxic effect and reactogenicity, necessitating expanding the repertoire of adjuvants with better biocompatibility, for instance, designing self-adjuvating polymeric carriers. We herein report a novel subunit vaccine delivery platform constructed via in situ free radical polymerization of C7A (2-(Hexamethyleneimino) ethyl methacrylate) and acrylamide around the surface of individual protein antigens. Using ovalbumin (OVA) as a model antigen, we observed substantial increases in both diameter (∼70 nm) and surface potential (-1.18 mV) following encapsulation, referred to as n(OVA)C7A. C7A's ultra pH sensitivity with a transition pH around 6.9 allows for rapid protonation in acidic environments. This property facilitates crucial processes such as endosomal escape and major histocompatibility complex (MHC)-I-mediated antigen presentation, culminating in the substantial CD8+ T cell activation. Additionally, compared to OVA nanocapsules without the C7A components and native OVA without modifications, we observed heightened B cell activation within the germinal center, along with remarkable increases in serum antibody and cytokine production. It's important to note that mounting evidence suggests that adjuvant effects, particularly its targeted stimulation of type I interferons (IFNs), can contribute to advantageous adaptive immune responses. Beyond its exceptional potency, the nanovaccine also demonstrated robust formation of immune memory and exhibited a favorable biosafety profile. These findings collectively underscore the promising potential of our nanovaccine in the realm of immunotherapy and vaccine development.

Bacteria-derived nanovesicles enhance tumour vaccination by trained immunity

Trained immunity enhances the responsiveness of immune cells to subsequent infections or vaccinations. Here we demonstrate that pre-vaccination with bacteria-derived outer-membrane vesicles, which contain large amounts of pathogen-associated molecular patterns, can be used to potentiate, and enhance, tumour vaccination by trained immunity. Intraperitoneal administration of these outer-membrane vesicles to mice activates inflammasome signalling pathways and induces interleukin-1β secretion. The elevated interleukin-1β increases the generation of antigen-presenting cell progenitors. This results in increased immune response when tumour antigens are delivered, and increases tumour-antigen-specific T-cell activation. This trained immunity increased protection from tumour challenge in two distinct cancer models.

Nanotechnology of inhalable vaccines for enhancing mucosal immunity

Vaccines are the cornerstone of world health. The majority of vaccines are formulated as injectable products, facing the drawbacks of cold chain transportation, needle-stick injuries, and primary systemic immunity. Inhalable vaccines exhibited unique advantages due to their small dose, easy to use, quick effect, and simultaneous induction of mucosal and systemic responses. Facing global pandemics, especially the coronavirus disease 2019 (COVID-19), a majority of inhalable vaccines are in preclinical or clinical trials. A better understanding of advanced delivery technologies of inhalable vaccines may provide new scientific insights for developing inhalable vaccines. In this review article, detailed immune mechanisms involving mucosal, cellular, and humoral immunity were described. The preparation methods of inhalable vaccines were then introduced. Advanced nanotechnologies of inhalable vaccines containing inhalable nucleic acid vaccines, inhalable adenovirus vector vaccines, novel adjuvant-assisted inhalable vaccines, and biomaterials for inhalable vaccine delivery were emphatically discussed. Meanwhile, the latest clinical progress in inhalable vaccines for COVID-19 and tuberculosis was discussed.

RNA Origami Functions as a Self-Adjuvanted Nanovaccine Platform for Cancer Immunotherapy

Peptide-based vaccines have been widely investigated in cancer immunotherapy. Despite their high specificity, safety, and low production cost, these vaccines have shown limited success in clinical studies, owing to their poor immunogenicity. Extensive efforts have been devoted to increasing the immunogenicity of peptide vaccines by mixing peptides with adjuvants and/or promoting their delivery to tumor-draining lymph nodes (TdLNs) for better antigen presentation by and maturation of dendritic cells. Among these efforts, the exploration of various nanoparticles has been at the forefront of the rational design and construction of peptide-based vaccines. Here, we present a nanovaccine platform that is built on a self-assembled RNA origami (RNA-OG) nanostructure. As previously reported, this RNA-OG nanostructure is a potent toll-like receptor (TLR)3 agonist. In addition, due to its robust synthesis and versatility in modification, RNA-OG could be readily linked to peptides of interest. Thus, these RNA-OG nanostructures function as adjuvanted nanocarriers to construct RNA-OG-peptide nanovaccines that are uniform in size, consistent in peptide loading, and highly stable. Here, we demonstrate that the assembled RNA-OG-peptide nanovaccines induced dendritic cell maturation, reduced tumor-mediated immunosuppression, and mobilized tumor-specific CD8+ T cell responses at the tumor site. Together, these actions led to the elicitation of an effective antitumor immunity that increased the survival of tumor-bearing mice. The combination of RNA-OG-based nanovaccines with the α-PD-1 immune checkpoint blockade further enhanced the immunity. Hence, our RNA-OG nanostructures represent a robust, simple, and highly effective platform to empower peptide-based vaccines for cancer immunotherapy.

Development and efficacy evaluation of a novel water-in-oil-in-water adjuvant for an inactivated foot-and-mouth disease vaccine

To develop a novel water-in-oil-in-water (W/O/W) adjuvant and evaluate the effect on foot-and-mouth disease (FMD) inactivated vaccine, in this study, we prepared the novel nano-emulsion adjuvant based on QS-21 (BEA) which is composed of the mixture of mineral oil Marcol52, surfactant Tween80, oleate polyoxyethylene ether ester, polyoxyethylene palmitic acid ester and span80, cosurfactant polyethylene glycol and QS-21. The two-step emulsification method formed the W/O/W nano-emulsion with two films and three-phase structures. The effective particle diameter of the BEA was about 184 nm, and it has good thermal stability. Then, BEA was emulsified as an adjuvant to prepare for the inactivated FMDV vaccine, and BALB/c mice and pigs were immunized to evaluate its safety and immunization effect. The results showed that the inactivated BEA-FMDV vaccine significantly increased BALB/c mice and pigs' antibodies and cytokine IFN-γ in serum. Meanwhile, the pig-neutralizing antibodies were higher than control group. Safety tests found no symptoms of FMD or significant toxic reactions. After 28 days of immunization, the protection rate can reach 93.3%. The BEA vaccine had good stability at 4 °C, no stratification after 180 days, and the content of 146S in the vaccine did not decrease. In conclusion, the BEA prepared in this study is suitable for FMDV inactivated vaccine and is an effective adjuvant.

Metal-polyphenol "prison" attenuated bacterial outer membrane vesicle for chemodynamics promoted in situ tumor vaccines

As natural adjuvants, the bacterial outer membrane vesicles (OMV) hold great potential in cancer vaccines. However, the inherent immunotoxicity of OMV and the rarity of tumor-specific antigens seriously hamper the clinical translation of OMV-based cancer vaccines. Herein, metal-phenolic networks (MPNs) are used to attenuate the toxicity of OMV, meanwhile, provide tumor antigens via the chemodynamic effect induced immunogenic cell death (ICD). Specifically, MPNs are assembled on the OMV surface through the coordination reaction between ferric ions and tannic acid. The iron-based "prison" is locally collapsed in the tumor microenvironment (TME) with both low pH and high ATP features, and thus the systemic toxicity of OMV is significantly attenuated. The released ferric ions in TME promote the ICD of cancer cells through Fenton reaction and then the generation of abundant tumor antigens, which can be used to fabricate in-situ vaccines by converging with OMV. Together with the immunomodulatory effect of OMV, potent tumor repression on a bilateral tumor model is achieved with good biosafety.

Nanoparticles and Antiviral Vaccines

Viruses have threatened human lives for decades, causing both chronic and acute infections accompanied by mild to severe symptoms. During the long journey of confrontation, humans have developed intricate immune systems to combat viral infections. In parallel, vaccines are invented and administrated to induce strong protective immunity while generating few adverse effects. With advancements in biochemistry and biophysics, different kinds of vaccines in versatile forms have been utilized to prevent virus infections, although the safety and effectiveness of these vaccines are diverse from each other. In this review, we first listed and described major pathogenic viruses and their pandemics that emerged in the past two centuries. Furthermore, we summarized the distinctive characteristics of different antiviral vaccines and adjuvants. Subsequently, in the main body, we reviewed recent advances of nanoparticles in the development of next-generation vaccines against influenza viruses, coronaviruses, HIV, hepatitis viruses, and many others. Specifically, we described applications of self-assembling protein polymers, virus-like particles, nano-carriers, and nano-adjuvants in antiviral vaccines. We also discussed the therapeutic potential of nanoparticles in developing safe and effective mucosal vaccines. Nanoparticle techniques could be promising platforms for developing broad-spectrum, preventive, or therapeutic antiviral vaccines.

Potentiating cancer vaccination by adjuvant-loaded cryo-shocked tumor cells

Cancer vaccine holds vast promise in potentiating tumor immunotherapy. Here, we developed a simple cancer vaccine based on the liquid nitrogen-treated cells (LNT cells) that engineered by one-shot shocking of the live tumor cells in liquid nitrogen. In this vaccine, the obtained LNT cells served as both tumor antigens and delivery vehicles to load the adjuvant imiquimod (R837). This design could achieve efficient co-uptake of antigen/adjuvant by antigen presenting cells (APCs) and prolong in vivo retention of tumor antigens and adjuvants. This adjuvant-loaded LNT cells augmented in vivo antitumor responses and enhanced survival in melanoma-bearing mouse model compared with conventional whole-cell vaccine of the mixture of tumor lysis and adjuvant.

Heteroantigen-assembled nanovaccine enhances the polyfunctionality of TILs against tumor growth and metastasis

The dysfunction of tumor infiltrating lymphocytes (TILs) directly correlates with out of control of tumor growth and metastasis. New approaches and insightful clarity for rescuing TILs dysfunction are urgently needed. Here, we design two heterogenous antigens based on MHC-I epitope and MHC-II epitope from tumor, and assemble heterogenous antigens by electrostatic interactions and π-π stacking into heteroantigen-assembled nanovaccine (HANV). HANV not only significantly increases the abundance of CD8+ and CD4+ TILs, but also elicits stronger polyfunctionality of CD8+ and CD4+ TILs in vivo. Enhanced polyfunctionality of CD8+ and CD4+ TILs positively correlate to suppression of tumor growth and metastasis in melanoma-bearing mouse models. We also validate that nucleotide-binding oligomerization domain-containing protein 2 (NOD2) dominantly enhances anti-tumor capacity of TILs in a temporal immunoregulation manner. This work presents a new insight in developing HANV as a rational strategy to shape TILs polyfunctionality for tumor growth and metastasis.

An Ionizable Lipid Material with a Vitamin E Scaffold as an mRNA Vaccine Platform for Efficient Cytotoxic T Cell Responses

RNA vaccines based on lipid nanoparticles (LNPs) with in vitro transcribed mRNA (IVT-mRNA) encapsulated are now a currently successful but still evolving modality of vaccines. One of the advantages of RNA vaccines is their ability to induce CD8+ T-cell-mediated cellular immunity that is indispensable for excluding pathogen-infected cells or cancer cells from the body. In this study, we report on the development of LNPs with an enhanced capability for inducing cellular immunity by using an ionizable lipid with a vitamin E scaffold. An RNA vaccine that contained this ionizable lipid and an IVT-mRNA encoding a model antigen ovalbumin (OVA) induced OVA-specific cytotoxic T cell responses and showed an antitumor effect against an E.G7-OVA tumor model. Vaccination with the LNPs conferred protection against lethal infection by Toxoplasma gondii using its antigen TgPF. The vitamin E scaffold-dependent type I interferon response was important for effector CD8+ T cell differentiation induced by the mRNA-LNPs. Our findings also revealed that conventional dendritic cells (cDCs) were essential for achieving CD8+ T cell responses induced by the mRNA-LNPs, while the XCR1-positive subset of cDCs, cDC1 specialized for antigen cross-presentation, was not required. Consistently, the mRNA-LNPs were found to selectively transfect another subset of cDCs, cDC2 that had migrated from the skin to lymph nodes, where they could make vaccine-antigen-dependent contacts with CD8+ T cells. The findings indicate that the activation of innate immune signaling by the adjuvant activity of the vitamin E scaffold and the expression of antigens in cDC2 are important for subsequent antigen presentation and the establishment of antigen-specific immune responses.

Carrier-Free Nanovaccine: An Innovative Strategy for Ultrahigh Melanoma Neoantigen Loading

In personalized cancer immunotherapy, developing an effective neoantigen nanovaccine with high immunogenicity is a significant challenge. Traditional nanovaccine delivery systems often require nanocarriers, which can hinder the delivery of the neoantigen and cause significant toxicity. In this study, we present an innovative strategy of carrier-free nanovaccine achieved through direct self-assembly of 2'-fluorinated CpG (2'F-CpG) with melanoma neoantigen peptide (Obsl1). Molecular dynamics simulations demonstrated that the introduction of a fluorine atom into CpG increases the noncovalent interaction between 2'F-CpG and Obsl1, which enhanced the loading of Obsl1 on 2'F-CpG, resulting in the spontaneous formation of a hybrid 2'F-CpG/Obsl1 nanovaccine. This nanovaccine without extra nanocarriers showed ultrahigh Obsl1 loading up to 83.19 wt %, increasing the neoantigen peptide uptake by antigen-presenting cells (APCs). In C57BL/6 mice models, we demonstrated the long-term preventive and therapeutic effects of the prepared 2'F-CpG/Obsl1 nanovaccine against B16F10 melanoma. Immunocellular analysis revealed that the nanovaccine activated innate and adaptive immune responses to cancer cells. Hence, this study established a simple, safe, and effective preparation strategy for a carrier-free neoantigen nanovaccine, which could be adapted for the future design of personalized cancer vaccines in clinical settings.

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.

mRNA Delivery Platform Based on Bacterial Outer Membrane Vesicles for Tumor Vaccine

The rapid display and delivery method for customized tumor mRNA vaccines is limited. Herein, bacteria-derived outer membrane vesicles (OMVs) are employed as an mRNA delivery platform by surface engineering of an RNA-binding protein, L7Ae. OMV-L7Ae can rapidly adsorb boxC/D sequence-labeled mRNA antigens through L7Ae-boxC/D binding and deliver them into HEK-293T and dendritic cells. This platform provides an mRNA delivery technology distinct from lipid nanoparticles (LNPs) for personalized mRNA tumor vaccination and with a Plug-and-Display strategy suitable for rapid preparation of the personalized mRNA tumor vaccine against varied tumor antigens. Key features OMVs are employed as an mRNA delivery platform through L7Ae-boxC/D binding.

Macro-microporous ZIF-8 MOF complexed with lysosomal pH-adjusting hexadecylsulfonylfluoride as tumor vaccine delivery systems for improving anti-tumor cellular immunity

Tumor vaccine therapy, which can induce tumor antigen-specific cellular immune responses to directly kill tumor cells, is considered to be one of the most promising tumor immunotherapies. How to elicit effective tumor antigen-specific cellular immunity is the key for the development of tumor vaccines. However, current tumor vaccines with conventional antigen delivery systems mainly induce humoral immunity but not effective cellular immunity. In this study, based on pH-sensitive, ordered macro-microporous zeolitic imidazolate framework-8 (SOM-ZIF-8) and hexadecylsulfonylfluoride (HDSF), an intelligent tumor vaccine delivery system SOM-ZIF-8/HDSF was developed to elicit potent cellular immunity. Results demonstrated that the SOM-ZIF-8 particles could efficiently encapsulate antigen into the macropores, promote antigen uptake by antigen-presenting cells, facilitate lysosomal escape, and enhance antigen cross-presentation and cellular immunity. In addition, the introduction of HDSF could up-regulate the lysosomal pH to protect antigens from acid degradation, which further promoted antigen cross-presentation and cellular immunity. The immunization tests showed that the tumor vaccines based on the delivery system improved antigen-specific cellular immune response. Moreover, the tumor vaccines significantly inhibited tumor growth in B16 melanoma-bearing C57BL/6 mice. These results indicate that SOM-ZIF-8/HDSF as an intelligent vaccine delivery system could be used for the development of novel tumor vaccines.

Production of a promising modular proteinaceous self-assembled delivery system for vaccination

Recently, there have been enormous advances in nano-delivery materials, especially safer and more biocompatible protein-based nanoparticles. Generally, proteinaceous nanoparticles (such as ferritin and virus-like particles) are self-assembled from some natural protein monomers. However, to ensure their capability of assembly, it is difficult to upgrade the protein structure through major modifications. Here, we have developed an efficient orthogonal modular proteinaceous self-assembly delivery system that could load antigens with an attractive coupling strategy. In brief, we constructed a nanocarrier by fusing two orthogonal domains-a pentameric cholera toxin B subunit and a trimer forming peptide-and an engineered streptavidin monomer for binding biotinylated antigens. After successfully preparing the nanoparticles, the receptor-binding domain of SARS-CoV-2 spike protein and influenza virus haemagglutination antigen are used as model antigens for further evaluation. We found that the biotinylated antigen is able to bind to the nanoparticles with high affinity and achieve efficient lymph node drainage when loaded on the nanoparticles. Then, T cells are greatly activated and the formation of germinal centers is observed. Experiments of two mouse models demonstrate the strong antibody responses and prophylactic effects of these nanovaccines. Thus, we establish a proof-of-concept for the delivery system with the potential to load diverse antigen cargos to generate high-performance nanovaccines, thereby offering an attractive platform technology for nanovaccine preparation.

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.

Long-acting vaccine delivery systems

Bolus vaccines are often administered multiple times due to rapid clearance and reduced transportation to draining lymph nodes resulting in inadequate activation of T and B lymphocytes. In order to achieve adaptive immunity, prolonged exposure of antigens to these immune cells is crucial. Recent research has been focusing on developing long-acting biomaterial-based vaccine delivery systems, which can modulate the release of encapsulated antigens or epitopes to facilitate enhanced antigen presentation in lymph nodes and subsequently achieve robust T and B cell responses. Over the past few years, various polymers and lipids have been extensively explored to develop effective biomaterial-based vaccine strategies. The article reviews relevant polymer and lipid-based strategies used to prepare long-acting vaccine carriers and discusses their results concerning immune responses.

Transforming Cold Tumors into Hot Ones with a Metal-Organic Framework-Based Biomimetic Nanosystem for Enhanced Immunotherapy

Immunotherapy has revolutionized the landscape in clinical tumor therapy, although the response rates in "cold" tumors are relatively low owing to the complex tumor microenvironment (TME). Cyclic guanosine monophosphate-adenosine monophosphate synthase/stimulator of interferon genes (cGAS/STING) pathway-inducing agents can reprogram the TME; however, their applications remain underutilized. Herein, we engineered a facile manganese-based metal-organic framework (Mn-MOF) encapsulating polyphyllin I (PPI) and coated it with red blood cell (RBC) membranes (RBC@Mn-MOF/PPI) that enhanced the cGAS/STING-mediated antitumor immunity. RBC@Mn-MOF/PPI was engineered by camouflaging it with a biomimetic RBC membrane for prolonged blood circulation and immune escape, which was also extended with TME-sensitive properties for triggering the release of PPI and Mn²⁺ to remodel the suppressive TME and augment antitumor immune responses. Furthermore, RBC@Mn-MOF/PPI helped transform cold tumors into "hot" ones by activating immune cells, as evidenced via dendritic cell maturation, cytotoxic T lymphocyte infiltration, and natural killer cell recruitment, thereby targeting primary and abscopal tumors and lung metastatic nodules. Therefore, our engineered nanosystem represents a novel strategy to transform immunologically "cold" tumors into "hot" ones by activating the cGAS/STING pathway, thereby addressing the major challenges associated with immunotherapy.

Adjuvanted quaternized chitosan composite aluminum nanoparticles-based vaccine formulation promotes immune responses in chickens

Aluminum adjuvant is a typical adjuvant that can promote humoral immune response, but it lacks the ability to effectively induce cellular immune response. The water-soluble N-2-Hydroxypropyl trimethyl ammonium chloride chitosan nanoparticles (N-2-HACC NPs) can enhance humoral and cellular immune responses of vaccines. To enable aluminum adjuvant to induce cellular immunity, the composite nano adjuvant N-2-HACC-Al NPs were synthesized by the N-2-HACC and aluminum sulfate (Al₂(SO₄)₃). The particle size and zeta potential of the N-2-HACC-Al NPs were 300.70 ± 24.90 nm and 32.28 ± 0.52 mV, respectively. The N-2-HACC-Al NPs have good thermal stability and biodegradability and lower cytotoxicity. In addition, to investigate the immunogenicity of the composite nano adjuvant, the combined inactivated vaccine against Newcastle disease (ND) and H9N2 avian influenza (AI) was prepared with the N-2-HACC-Al NPs as a vaccine adjuvant. The immune effect of the vaccine (N-2-HACC-Al/NDV-AIV) was evaluated by chicken in vivo immunization. The vaccine induced higher levels of serum IgG, IL-4, and IFN-γ than those of the commercial combined inactivated vaccine against ND and H9N2 AI. The levels of IFN-γ were more than twice those of the commercial vaccine at 7 days post the immunization. The N-2-HACC-Al NPs could be used as an efficient nano adjuvant to enhance the effectiveness of vaccine and have immense application potential.

Carbon Dots and Tumor Antigen Conjugates as Nanovaccines for Elevated Cancer Immunotherapy

Cancer immunotherapy has become one of the current research hotspots. However, the deficiencies including restricted immunogenicity, insufficient antigen presentation, and low responsive rate limited their therapeutic applications. Own to the small size and excellent biocompatibility, carbon dots (CDs) can serve as nanovectors to improve the efficacy of cancer immunotherapy. Herein, a tumor antigen-based nanovaccines (GMal+B16F10-Ag and GMal+CT26-Ag) by the conjugation of CDs with the tumor cell-derived antigens (B16F10-Ag and CT26-Ag) is constructed. These nanovaccines can be effectively taken up by dendritic cells (DC2.4), promote DC cell maturation, cross-present the antigen to T cells, specifically target B16F10 melanoma or CT26 colon cancers, and inhibit tumor growth distinctly. This work illustrates the promise of CDs acting as versatile carriers for antigen delivery to achieve the optimal immunotherapeutic outcomes.

Natural Polymeric Composites Derived from Animals, Plants, and Microbes for Vaccine Delivery and Adjuvant Applications: A Review

A key element in ensuring successful immunization is the efficient delivery of vaccines. However, poor immunogenicity and adverse inflammatory immunogenic reactions make the establishment of an efficient vaccine delivery method a challenging task. The delivery of vaccines has been performed via a variety of delivery methods, including natural-polymer-based carriers that are relatively biocompatible and have low toxicity. The incorporation of adjuvants or antigens into biomaterial-based immunizations has demonstrated better immune response than formulations that just contain the antigen. This system may enable antigen-mediated immunogenicity and shelter and transport the cargo vaccine or antigen to the appropriate target organ. In this regard, this work reviews the recent applications of natural polymer composites from different sources, such as animals, plants, and microbes, in vaccine delivery systems.

Orchestrated Cytosolic Delivery of Antigen and Adjuvant by Manganese Ion-Coordinated Nanovaccine for Enhanced Cancer Immunotherapy

Cancer vaccines have received tremendous attention in cancer immunotherapy due to their capability to induce a tumor-specific immune response. However, their effectiveness is compromised by the insufficient spatiotemporal delivery of antigens and adjuvants in the subcellular level to induce a robust CD8⁺ T cell response. Herein, a cancer nanovaccine G5-pBA/OVA@Mn is prepared through multiple interactions of manganese ions (Mn²⁺), benzoic acid (BA)-modified fifth generation polyamidoamine (G5-PAMAM) dendrimer, and the model protein antigen ovalbumin (OVA). In the nanovaccine, Mn²⁺ not only exerts a structural function to assist OVA loading as well as its endosomal escape, but works as an adjuvant of stimulator of interferon genes (STING) pathway. These collaboratively facilitate the orchestrated codelivery of OVA antigen and Mn²⁺ into cell cytoplasm. Vaccination with G5-pBA/OVA@Mn not only shows a prophylactic effect, but also significantly inhibits growth against B16-OVA tumors, indicating its great potential for cancer immunotherapy.

Regulating T-cell metabolic reprogramming and blocking PD-1 co-promote personalized postoperative autologous nanovaccines

Cytotoxic T lymphocytes (CTLs) are central effector cells in antitumor immunotherapy. However, the complexity of immunosuppressive factors in the immune system contributes to the low response rates of current CTL-based immunotherapies. Here, we propose a novel holistic strategy including a priming response, promoting activity, and relieving suppression of CTLs, aiming to strengthen the effect of personalized postoperative autologous nanovaccines. The nanovaccine (C/G-HL-Man) fused the autologous tumor cell membrane with dual adjuvants (CpG and cGAMP), and could effectively accumulate in lymph nodes and promote antigen cross presentation by dendritic cells to prime a sufficient specific-CTL response. The PPAR-α agonist fenofibrate was used to regulate T-cell metabolic reprogramming to promote antigen-specific CTLs activity in the harsh metabolic tumor microenvironment. Finally, the PD-1 antibody was used to relieve the suppression of specific-CTLs in the immunosuppressive tumor microenvironment. In vivo, the C/G-HL-Man exhibited strong antitumor effect in the B16F10 murine tumor prevention model and the B16F10 postoperative recurrence model. In particular, combination therapy with nanovaccines, fenofibrate, and PD-1 antibody effectively inhibited the progression of recurrent melanoma and prolonged the survival time. Our work highlights the critical role of the T-cell metabolic reprogramming and PD-1 blocking in autologous nanovaccines, offering a novel strategy for strengthening the function of CTLs.

Exosome-based delivery of VP1 protein conferred enhanced resistance of mice to CVB3-induced viral myocarditis

Coxsackievirus B3 (CVB3) is an important cause of viral myocarditis with no vaccine available in clinic. Herein we constructed an exosome-based anti-CVB3 vaccine (Exo-VP1), and compared its immunogenicity and immunoprotection with our previously reported recombinant VP1 protein (rVP1) vaccine. We found that compared with the 25 μg rVP1 vaccine, Exo-VP1 vaccine containing only 2 μg VP1 protein induced much stronger CVB3-specific T cell proliferation and CTL responses (with an increase of more than 70% and 40% respectively), and elicited greater splenic Th1/CTL associated cytokines (IFN-γ, TNF-α and IL-12). Furthermore, higher IgG levels with increased neutralizing titers and avidity were also evidenced in Exo-VP1 group. Consistently, Exo-VP1 group exhibited enhanced resistance to viral myocarditis than rVP1 vaccine, reflected by reduced cardiac viral loads, improved myocardial inflammation and an increased survival rate. Collectively, we reported that Exo-VP1 might present a more potent CVB3 vaccine candidate than rVP1 vaccine.

Normalizing the Immune Macroenvironment via Debulking Surgery to Strengthen Tumor Nanovaccine Efficacy and Eliminate Metastasis

In tumor nanovaccines, nanocarriers enhance the delivery of tumor antigens to antigen-presenting cells (APCs), thereby ensuring the robust activation of tumor antigen-specific effector T-cells to kill tumor cells. Through employment of their high immunogenicity and nanosize, we have developed a "Plug-and-Display" delivery platform on the basis of bacterial outer membrane vesicles (OMVs) for tumor nanovaccines (NanoVac), which can rapidly display different tumor antigens and efficiently eliminate lung metastases of melanoma. In this study, we first upgraded the NanoVac to increase their antigen display efficiency. However, we found that the presence of a subcutaneous xenograft seriously hampered the efficiency of NanoVac to eliminate lung metastases, with the subcutaneous xenograft mimicking the primary tumor burden in clinical practice. The primary tumor secreted significant amounts of granulocyte colony-stimulating factor (G-CSF) and altered the epigenetic features of granulocyte monocyte precursor cells (GMPs) in the bone marrow, thus disrupting systemic immunity, particularly the function of APCs, and ultimately resulting in NanoVac failure to affect metastases. These changes in the systemic immune macroenvironment were plastic, and debulking surgery of primary tumor resection reversed the dysfunction of APCs and failure of NanoVac. These results demonstrate that, in addition to the formulation design of the tumor nanovaccines themselves, the systemic immune macroenvironment incapacitated by tumor development is another key factor that cannot be ignored to affect the efficiency of tumor nanovaccines, and the combination of primary tumor resection with NanoVac is a promising radical treatment for widely metastatic tumors.

Biomimetic nanoparticles for tumor immunotherapy

Currently, tumor treatment research still focuses on the cancer cells themselves, but the fact that the immune system plays an important role in inhibiting tumor development cannot be ignored. The activation of the immune system depends on the difference between self and non-self. Unfortunately, cancer is characterized by genetic changes in the host cells that lead to uncontrolled cell proliferation and evade immune surveillance. Cancer immunotherapy aims to coordinate a patient's immune system to target, fight, and destroy cancer cells without destroying the normal cells. Nevertheless, antitumor immunity driven by the autoimmune system alone may be inadequate for treatment. The development of drug delivery systems (DDS) based on nanoparticles can not only promote immunotherapy but also improve the immunosuppressive tumor microenvironment (ITM), which provides promising strategies for cancer treatment. However, conventional nano drug delivery systems (NDDS) are subject to several limitations in clinical transformation, such as immunogenicity and the potential toxicity risks of the carrier materials, premature drug leakage at off-target sites during circulation and drug load content. In order to address these limitations, this paper reviews the trends and progress of biomimetic NDDS and discusses the applications of each biomimetic system in tumor immunotherapy. Furthermore, we review the various combination immunotherapies based on biomimetic NDDS and key considerations for clinical transformation.

mRNA vaccines: A novel weapon to control infectious diseases

Infectious diseases have always threatened human life, but with the development of vaccines, effective strategies for preventing and controlling these diseases have become available. The global outbreak of COVID-19 ushered in the advent of mRNA vaccine technologies, which quickly led to the introduction of mRNA vaccines effective against SARS-CoV-2. The success of this approach has stimulated research into the use of mRNA vaccines in the fight against other emerging as well as remerging infectious diseases. This review examines the constructive strategies and delivery systems used in mRNA vaccines and provides an overview of current clinical trials of those vaccines in the prevention of infectious diseases. The underlying mechanisms of mRNA vaccines are also discussed, including the double-edged sword of the innate immune response. Finally, the challenges but also the potential of mRNA vaccines are considered.

Engineered Bacterial Outer Membrane Vesicles as Controllable Two-Way Adaptors to Activate Macrophage Phagocytosis for Improved Tumor Immunotherapy

The most immune cells infiltrating tumor microenvironment (TME), tumor-associated macrophages (TAMs) closely resemble immunosuppressive M2-polarized macrophages. Moreover, tumor cells exhibit high expression of CD47 "don't eat me" signal, which obstructs macrophage phagocytosis. The precise and efficient activation of TAMs is a promising approach to tumor immunotherapy; however, re-education of macrophages remains a challenge. Bacteria-derived outer membrane vesicles (OMVs) are highly immunogenic nanovesicles that can robustly stimulate macrophages. Here, an OMV-based controllable two-way adaptor is reported, in which a CD47 nanobody (CD47nb) is fused onto OMV surface (OMV-CD47nb), with the outer surface coated with a polyethylene glycol (PEG) layer containing diselenide bonds (PEG/Se) to form PEG/Se@OMV-CD47nb. The PEG/Se layer modification not only mitigates the immunogenicity of OMV-CD47nb, thereby remarkedly increasing the dose that can be administered safely through intravenous injection, but also equips the formulation with radiation-triggered controlled release of OMV-CD47nb. Application of radiation to tumors in mice injected with the nanoformulation results in remodeling of TME. As two-way adaptors, OMV-CD47nb activates TAM phagocytosis of tumor cells via multiple pathways, including induction of M1 polarization and blockade of "don't eat me" signal. Moreover, this activation of TAMs results in the stimulation of T cell-mediated antitumor immunity through effective antigen presentation.

Exploration of immune response mechanisms in cadmium and copper co-exposed juvenile golden cuttlefish (Sepia esculenta) based on transcriptome profiling

Sepia esculenta is a popular economic cephalopod with high yield, delicious meat, and rich nutrition. With the rapid development of heavy industry and medical industry, a large amount of waste has been released into the ocean recklessly in recent years, inducing a significant increase in the content of heavy metals, especially cadmium (Cd) and copper (Cu), in the ocean. This phenomenon significantly affects the growth and development of S. esculenta, causing a serious blow to its artificial breeding. In this study, transcriptome analysis is used to initially explore immune response mechanisms of Cd and Cu co-exposed juvenile S. esculenta. The results show that 1,088 differentially expressed genes (DEGs) are identified. And DEGs functional enrichment analysis results suggests that co-exposure may promote inflammatory and innate immune responses in juvenile S. esculenta. Fifteen key genes that might regulate the immunity of S. esculenta are identified using protein-protein interaction (PPI) network and KEGG enrichment analyses, of which the three genes with the highest number of interactions or involve in more KEGG pathways are identified as hub genes that might significantly affect the immune response processes. Comprehensive analysis of PPI network and KEGG signaling pathway is used for the first time to explore co-exposed S. esculenta juvenile immune response processes. Our results preliminarily reveal immune response mechanisms of cephalopods exposed to heavy metals and provide a valuable resource for further understanding of mollusk immunity.

Nanocarriers for effective delivery: modulation of innate immunity for the management of infections and the associated complications

Innate immunity is the first line of defense against invading pathogens. Innate immune cells can recognize invading pathogens through recognizing pathogen-associated molecular patterns (PAMPs) via pattern recognition receptors (PRRs). The recognition of PAMPs by PRRs triggers immune defense mechanisms and the secretion of pro-inflammatory cytokines such as TNF-α, IL-1β, and IL-6. However, sustained and overwhelming activation of immune system may disrupt immune homeostasis and contribute to inflammatory disorders. Immunomodulators targeting PRRs may be beneficial to treat infectious diseases and their associated complications. However, therapeutic performances of immunomodulators can be negatively affected by (1) high immune-mediated toxicity, (2) poor solubility and (3) bioactivity loss after long circulation. Recently, nanocarriers have emerged as a very promising tool to overcome these obstacles owning to their unique properties such as sustained circulation, desired bio-distribution, and preferred pharmacokinetic and pharmacodynamic profiles. In this review, we aim to provide an up-to-date overview on the strategies and applications of nanocarrier-assisted innate immune modulation for the management of infections and their associated complications. We first summarize examples of important innate immune modulators. The types of nanomaterials available for drug delivery, as well as their applications for the delivery of immunomodulatory drugs and vaccine adjuvants are also discussed.

Nanocarriers based on bacterial membrane materials for cancer vaccine delivery

Here we present a protocol for the construction and use of two types of nanocarrier based on bacterial membrane materials for cancer vaccine delivery. Cancer vaccines induce tumor regression through triggering the specific T-cell responses against tumor neoantigens, a process that can be enhanced by nanocarrier delivery. Inspired by the body's natural immune defenses against bacterial invasion, we have developed two different types of nanocarrier based on bacterial membrane materials, which employ genetically engineered outer-membrane vesicles (OMVs), or hybrid membrane vesicles containing bacterial cytoplasmic membrane, respectively. The OMV-based nanocarriers can rapidly display different tumor antigens through the surface modified Plug-and-Display system, suitable for customized cancer vaccines when the tumor neoantigens can be identified. The hybrid membrane-based nanocarriers are prepared through fusion of the bacterial cytoplasmic membrane and the primary tumor cell membrane from surgically removed tumor tissues, possessing unique advantages as personalized cancer vaccines when the neoantigens are not readily available. Compared with chemically synthesized nanocarriers such as liposomes and polymer without intrinsic adjuvant properties, owing to the large amounts of pathogen-associated molecular patterns, the two nanocarriers can activate the antigen-presenting cells while delivering multiple antigens, thus inducing effective antigen presentation and robust adaptive immune activation. Excluding bacterial culture and tumor tissue collection, the preparation of OMV- and hybrid membrane-based nanocarriers takes ~8 h and 10 h for tumor vaccine construction, respectively. We also detail how to use these nanocarriers to create cancer nanovaccines and evaluate their immunostimulatory and antitumor effects.

Nanotechnology-facilitated vaccine development during the coronavirus disease 2019 (COVID-19) pandemic

Coronavirus disease 2019 (COVID-19) continually poses a significant threat to the human race, and prophylactic vaccination is the most potent approach to end this pandemic. Nanotechnology is widely adopted during COVID-19 vaccine development, and the engineering of nanostructured materials such as nanoparticles has opened new possibilities in innovative vaccine development by improving the design and accelerating the development process. This review aims to comprehensively understand the current situation and prospects of nanotechnology-enabled vaccine development against the COVID-19 pandemic, with an emphasis on the interplay between nanotechnology and the host immune system.

Image-guided/improved diseases management: From immune-strategies and beyond

Timely and accurate assessment and diagnosis are extremely important and beneficial for all diseases, especially for some of the major human disease, such as cancers, cardiovascular diseases, infectious diseases, and neurodegenerative diseases. Limited by the variable disease microenvironment, early imperceptible symptoms, complex immune system interactions, and delayed clinical phenotypes, disease diagnosis and treatment are difficult in most cases. Molecular imaging (MI) techniques can track therapeutic drugs and disease sites in vivo and in vitro in a non-invasive, real-time and visible strategies. Comprehensive visual imaging and quantitative analysis based on different levels can help to clarify the disease process, pathogenesis, drug pharmacokinetics, and further evaluate the therapeutic effects. This review summarizes the application of different MI techniques in the diagnosis and treatment of these major human diseases. It is hoped to shed a light on the development of related technologies and fields.

Prognostic Value of Immunotyping Combined with Targeted Therapy in Patients with Non-Small-Cell Lung Cancer and Establishment of Nomogram Model

Objective

Bioinformatics methods were used to analyze non-small-cell lung cancer gene chip data, screen differentially expressed genes (DEGs), explore biomarkers related to NSCLC prognosis, provide new targets for the treatment of NSCLC, and build immunotyping and line-map model.

Methods

NSCLC-related gene chip data were downloaded from the GEO database, and the common DEGs of the two datasets were screened by using the GEO2R tool and FunRich 3.1.3 software. DAVID database was used for GO analysis and KEGG analysis of DEGs, and protein-protein interaction (PPI) network was constructed by STRING database and Cytoscape 3.8.0 software, and the top 20 hub genes were analyzed and screened out. The expression of pivot genes and their relationship with prognosis were verified by multiple external databases.

Results

159 common DEGs were screened from the two datasets. PPI network was constructed and analyzed, and the genes with the top 20 connectivity were selected as the pivotal genes of this study. The results of survival analysis and the patients' survival curve was reflected in the line graph model of NSCLC.

Conclusion

Through the screening and identification of the VIM-AS1 gene, as well as the analysis of immune infiltration and immune typing, the successful establishment of the rosette model has a certain guiding value for the molecular targeted therapy of patients with non-small-cell lung cancer.

Nanocarriers for Drug Delivery: An Overview with Emphasis on Vitamin D and K Transportation

Mounting evidence shows that supplementation with vitamin D and K or their analogs induces beneficial effects in various diseases, e.g., osteoarticular, cardiovascular, or carcinogenesis. The use of drugs delivery systems via organic and inorganic nanocarriers increases the bioavailability of vitamins and analogs, enhancing their cellular delivery and effects. The nanotechnology-based dietary supplements and drugs produced by the food and pharmaceutical industries overcome the issues associated with vitamin administration, such as stability, absorption or low bioavailability. Consequently, there is a continuous interest in optimizing the carriers' systems in order to make them more efficient and specific for the targeted tissue. In this pioneer review, we try to circumscribe the most relevant aspects related to nanocarriers for drug delivery, compare different types of nanoparticles for vitamin D and K transportation, and critically address their benefits and disadvantages.

Antithrombotic Therapy by Regulating the ROS-Mediated Thrombosis Microenvironment and Specific Nonpharmaceutical Thrombolysis Using Prussian Blue Nanodroplets

In thrombotic diseases, the effects of reactive oxygen species (ROS)-mediated oxidative stress as a "perpetrator" in thrombosis must be resolved. Accordingly, an insufficient understanding of thrombus therapy prompted the authors to pursue a more comprehensive and efficient antithrombotic treatment strategy. A Prussian blue (PB)-based nanodroplet system (PB-PFP@PC) is designed using PB and perfluorinated pentane (PFP) in the core, and a targeting peptide (CREKA, Cys-Arg-Glu-Lys-Ala) is attached to poly(lactic-coglycolic acid) (PLGA) as the delivery carrier shell. Upon near-infrared (NIR) laser irradiation, PB and PFP jointly achieve an unprecedented dual strategy for drug-free thrombolysis: photothermal therapy (PTT) combined with optical droplet vaporization (ODV). PB, a nanoenzyme, also regulates the vascular microenvironment via its antioxidant activity to continuously scavenge abnormally elevated ROS and correspondingly reduce inflammatory factors in the thrombus site. This study provides a demonstration of not only the potential of ODV in thrombus therapy but also the mechanism underlying PTT thrombolysis due to thermal ablation-induced fibrin network structural damage. Moreover, PB catalyzes ROS to generate oxygen (O₂ ), which combines with the ODV effect, enhancing the ultrasound signal. Thus, regulation of the thrombosis microenvironment combined with specific nonpharmaceutical thrombolysis by PB nanodroplets provides a more comprehensive and efficient antithrombotic therapeutic strategy.

Supramolecular biomaterials for enhanced cancer immunotherapy

Cancer immunotherapy has achieved promising clinical results. However, many limitations associated with current cancer immunotherapy still exist, including low response rates and severe adverse effects in patients. Engineering biomaterials for...

Delivery of nanovaccine towards lymphoid organs: recent strategies in enhancing cancer immunotherapy

With the in-depth exploration on cancer therapeutic nanovaccines, increasing evidence shows that the poor delivery of nanovaccines to lymphoid organs has become the culprit limiting the rapid induction of anti-tumor immune response. Unlike the conventional prophylactic vaccines that mainly form a depot at the injection site to gradually trigger durable immune response, the rapid proliferation of tumors requires an efficient delivery of nanovaccines to lymphoid organs for rapid induction of anti-tumor immunity. Optimization of the physicochemical properties of nanovaccine (e.g., size, shape, charge, colloidal stability and surface ligands) is an effective strategy to enhance their accumulation in lymphoid organs, and nanovaccines with dynamic structures are also designed for precise targeted delivery of lymphoid organs or their subregions. The recent progress of these nanovaccine delivery strategies is highlighted in this review, and the challenges and future direction are also discussed.