Enhanced antitumor immunity by targeting dendritic cells with tumor cell lysate-loaded chitosan nanoparticles vaccine

Advances in engineered nanosystems: immunomodulatory interactions for therapeutic applications

Advances in nanotechnology have led to significant progress in the design and fabrication of nanoparticles (NPs) with improved therapeutic properties. NPs have been explored for modulating the immune system, serving as carriers for drug delivery or vaccine adjuvants, or acting as therapeutics themselves against a wide range of deadly diseases. The combination of NPs with immune system-targeting moieties has facilitated the development of improved targeted immune therapies. Targeted delivery of therapeutic agents using NPs specifically to the disease-affected cells, distinguishing them from other host cells, offers the major advantage of concentrating the therapeutic effect and reducing systemic side effects. Furthermore, the properties of NPs, including size, shape, surface charge, and surface modifications, influence their interactions with the targeted biological components. This review aims to provide insights into these diverse emerging and innovative approaches that are being developed and utilized for modulating the immune system using NPs. We reviewed various types of NPs composed of different materials and their specific application for modulating the immune system. Furthermore, we focused on the mechanistic effects of these therapeutic NPs on primary immune components, including T cells, B cells, macrophages, dendritic cells, and complement systems. Additionally, a recent overview of clinically approved immunomodulatory nanomedicines and potential future perspectives, offering new paradigms of this field, is also highlighted.

Cancer mRNA vaccines: clinical advances and future opportunities

mRNA vaccines have been revolutionary in terms of their rapid development and prevention of SARS-CoV-2 infections during the COVID-19 pandemic, and this technology has considerable potential for application to the treatment of cancer. Compared with traditional cancer vaccines based on proteins or peptides, mRNA vaccines reconcile the needs for both personalization and commercialization in a manner that is unique to each patient but not beholden to their HLA haplotype. A further advantage of mRNA vaccines is the availability of engineering strategies to improve their stability while retaining immunogenicity, enabling the induction of complementary innate and adaptive immune responses. Thus far, no mRNA-based cancer vaccines have received regulatory approval, although several phase I-II trials have yielded promising results, including in historically poorly immunogenic tumours. Furthermore, many early phase trials testing a wide range of vaccine designs are currently ongoing. In this Review, we describe the advantages of cancer mRNA vaccines and advances in clinical trials using both cell-based and nanoparticle-based delivery methods, with discussions of future combinations and iterations that might optimize the activity of these agents.

Fatty acid-modified chitosan and nanoencapsulation of essential oils: A snapshot of applications

Chitosan (CS) and its modification with fatty acid (FA) in addition to the nanoencapsulation with essential oils (EOs) have emerged as promising approaches with diverse applications, particularly in food and fruit preservation. This review aims to curate data on the prospects of CS modified with FA as nanostructures, serving as carriers for EOs and its application in the preservation of fruits. A narrative review with no restricted period was used for the general overview of CS and strategies for its modification with FA. Report on CS modified with FA and nanoencapsulation with EO and their applications were appraised. The prospects of CS modified with FA and EO nanoencapsulation in food and fruit preservation were outlined. Most chitosan-fatty acid (CS-FA) studies have found relevance in water, medical and pharmaceutical industries, with few studies on food preservation. CS-FA formulation with EOs shows substantial potential in preserving fruits and will significantly impact the food industry in the future by extending the shelf life of fruits and reducing food waste.

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.

Dual-mRNA Delivery Using Tumor Cell Lysate-Based Multifunctional Nanoparticles as an Efficient Colon Cancer Immunogene Therapy

Background

Messenger RNA (mRNA)-based immunogene therapy holds significant promise as an emerging tumor therapy approach. However, the delivery efficiency of existing mRNA methods and their effectiveness in stimulating anti-tumor immune responses require further enhancement. Tumor cell lysates containing tumor-specific antigens and biomarkers can trigger a stronger immune response to tumors. In addition, strategies involving multiple gene therapies offer potential optimization paths for tumor gene treatments.

Methods

Based on the previously developed ideal mRNA delivery system called DOTAP-mPEG-PCL (DMP), which was formed through the self-assembly of 1.2-dioleoyl-3-trimethylammonium-propane (DOTAP) and methoxypoly (ethylene glycol)-b-poly (ε-caprolactone) (mPEG-PCL), we introduced a fused cell-penetrating peptide (fCPP) into the framework and encapsulated tumor cell lysates to form a novel nanovector, termed CLSV system (CLS: CT26 tumor cell lysate, V: nanovector). This system served a dual purpose of facilitating the delivery of two mRNAs and enhancing tumor immunogene therapy through tumor cell lysates.

Results

The synthesized CLSV system had an average size of 241.17 nm and a potential of 39.53 mV. The CLSV system could not only encapsulate tumor cell lysates, but also deliver two mRNAs to tumor cells simultaneously, with a transfection efficiency of up to 60%. The CLSV system effectively activated the immune system such as dendritic cells to mature and activate, leading to an anti-tumor immune response. By loading Bim-encoded mRNA and IL-23A-encoded mRNA, CLSV/Bim and CLSV/IL-23A complexes were formed, respectively, to further induce apoptosis and anti-tumor immunity. The prepared CLSV/dual-mRNA complex showed significant anti-cancer effects in multiple CT26 mouse models.

Conclusion

Our results suggest that the prepared CLSV system is an ideal delivery system for dual-mRNA immunogene therapy.

Probiotic-derived amphiphilic exopolysaccharide self-assembling adjuvant delivery platform for enhancing immune responses

Enhancing immune response activation through the synergy of effective antigen delivery and immune enhancement using natural, biodegradable materials with immune-adjuvant capabilities is challenging. Here, we present NAPSL.p that can activate the Toll-like receptor 4 (TLR4) pathway, an amphiphilic exopolysaccharide, as a potential self-assembly adjuvant delivery platform. Its molecular structure and unique properties exhibited remarkable self-assembly, forming a homogeneous nanovaccine with ovalbumin (OVA) as the model antigen. When used as an adjuvant, NAPSL.p significantly increased OVA uptake by dendritic cells. In vivo imaging revealed prolonged pharmacokinetics of NAPSL. p-delivered OVA compared to OVA alone. Notably, NAPSL.p induced elevated levels of specific serum IgG and isotype titers, enhancing rejection of B16-OVA melanoma xenografts in vaccinated mice. Additionally, NAPSL.p formulation improved therapeutic effects, inhibiting tumor growth, and increasing animal survival rates. The nanovaccine elicited CD4+ and CD8+ T cell-based immune responses, demonstrating the potential for melanoma prevention. Furthermore, NAPSL.p-based vaccination showed stronger protective effects against influenza compared to Al (OH)3 adjuvant. Our findings suggest NAPSL.p as a promising, natural self-adjuvanting delivery platform to enhance vaccine design across applications.

Preparation and characterization of curdlan-chitosan conjugate nanoparticles as mucosal adjuvants for intranasal influenza H1N1 subunit vaccine

Intranasal vaccination offers crucial protection against influenza virus pandemics. However, antigens, especially subunit antigens, often fail to induce effective immune responses without the help of immune adjuvants. Our research has demonstrated that a polyelectrolyte complex, composed of curdlan sulfate/O-(2-hydroxyl) propyl-3-trimethyl ammonium chitosan chloride (CS/O-HTCC), effectively triggers both mucosal and systemic immune responses when administrated intranasal. In this study, stable nanoparticles formed by curdlan-O-HTCC conjugate (CO NP) were prepared and characterized. Furthermore, the efficacy of CO NP was evaluated as a mucosal adjuvant in an intranasal influenza H1N1 subunit vaccine. The results revealed that CO NP exhibits uniform and spherical morphology, with a size of 190.53 ± 4.22 nm, and notably, it remains stable in PBS at 4 °C for up to 6 weeks. Biological evaluation demonstrated that CO NP stimulates the activation of antigen-presenting cells (APCs), including macrophages and dendritic cells (DCs), both in vitro and in vivo. Furthermore, intranasal administration of CO NP effectively elicits cellular and humoral immune responses, notably enhancing mucosal immunity. Thus, CO NP emerges as a promising mucosal adjuvant for influenza subunit vaccines.

The Intellectual Landscape of Nanovaccines: A Bibliometric Perspective on Scientific Progress and Future Directions

This bibliometric study provides a comprehensive analysis of the burgeoning field of nanovaccine research, leveraging data sourced from Scopus and employing the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) flowchart for the meticulous screening, inclusion, and exclusion of relevant studies. Utilizing sophisticated bibliometric tools, such as Biblioshiny and CiteSpace, we dissected the expansive literature to unearth critical insights into the annual scientific output, identifying key contributors and pivotal publications that have shaped the domain. The analysis delineates the most influential authors, sources, and globally cited documents, offering a macroscopic view of the field's intellectual structure and growth trajectory. Trend topics and thematic mapping underscored the evolution of research foci, from fundamental immunological mechanisms to cutting-edge nanomaterial applications. Factorial analysis and keyword co-occurrence networks revealed the intricate associations and thematic concentrations within the literature. The study's robust methodology also pinpointed the keywords exhibiting the strongest citation bursts, signifying emergent areas of intense academic interest. Networks of cited authors illuminated collaborative patterns among scholars, while timeline network visualizations of country collaborations depicted the global interplay in nanovaccine development. Crucially, this study identified notable research gaps and practical implications, suggesting directions for future investigation and highlighting the translational potential of nanovaccines in public health and personalized medicine. This bibliometric investigation not only maps the current landscape but also charts a course for the trajectory of nanovaccine research, emphasizing its role as a cornerstone of innovative immunotherapeutic strategies.

Nanoparticles in tumor microenvironment remodeling and cancer immunotherapy

Cancer immunotherapy and vaccine development have significantly improved the fight against cancers. Despite these advancements, challenges remain, particularly in the clinical delivery of immunomodulatory compounds. The tumor microenvironment (TME), comprising macrophages, fibroblasts, and immune cells, plays a crucial role in immune response modulation. Nanoparticles, engineered to reshape the TME, have shown promising results in enhancing immunotherapy by facilitating targeted delivery and immune modulation. These nanoparticles can suppress fibroblast activation, promote M1 macrophage polarization, aid dendritic cell maturation, and encourage T cell infiltration. Biomimetic nanoparticles further enhance immunotherapy by increasing the internalization of immunomodulatory agents in immune cells such as dendritic cells. Moreover, exosomes, whether naturally secreted by cells in the body or bioengineered, have been explored to regulate the TME and immune-related cells to affect cancer immunotherapy. Stimuli-responsive nanocarriers, activated by pH, redox, and light conditions, exhibit the potential to accelerate immunotherapy. The co-application of nanoparticles with immune checkpoint inhibitors is an emerging strategy to boost anti-tumor immunity. With their ability to induce long-term immunity, nanoarchitectures are promising structures in vaccine development. This review underscores the critical role of nanoparticles in overcoming current challenges and driving the advancement of cancer immunotherapy and TME modification.

Therapeutic applications of carbohydrate-based compounds: a sweet solution for medical advancement

Carbohydrates, one of the most abundant biomolecules found in nature, have been seen traditionally as a dietary component of foods. Recent findings, however, have unveiled their medicinal potential in the form of carbohydrates-derived drugs. Their remarkable structural diversity, high optical purity, bioavailability, low toxicity and the presence of multiple functional groups have positioned them as a valuable scaffold and an exciting frontier in contemporary therapeutics. At present, more than 170 carbohydrates-based therapeutics have been granted approval by varying regulatory agencies such as United States Food and Drug Administration (FDA), Japan Pharmaceuticals and Medical Devices Agency (PMDA), Chinese National Medical Products Administration (NMPA), and the European Medicines Agency (EMA). This article explores an overview of the fascinating potential and impact of carbohydrate-derived compounds as pharmacological agents and drug delivery vehicles.

Nanomaterial Delivery Vehicles for the Development of Neoantigen Tumor Vaccines for Personalized Treatment

Tumor vaccines have been considered a promising therapeutic approach for treating cancer in recent years. With the development of sequencing technologies, tumor vaccines based on neoantigens or genomes specifically expressed in tumor cells, mainly in the form of peptides, nucleic acids, and dendritic cells, are beginning to receive widespread attention. Therefore, in this review, we have introduced different forms of neoantigen vaccines and discussed the development of these vaccines in treating cancer. Furthermore, neoantigen vaccines are influenced by factors such as antigen stability, weak immunogenicity, and biosafety in addition to sequencing technology. Hence, the biological nanomaterials, polymeric nanomaterials, inorganic nanomaterials, etc., used as vaccine carriers are principally summarized here, which may contribute to the design of neoantigen vaccines for improved stability and better efficacy.

Nanovaccines: An effective therapeutic approach for cancer therapy

Cancer vaccines hold considerable promise for the immunotherapy of solid tumors. Nanomedicine offers several strategies for enhancing vaccine effectiveness. In particular, molecular or (sub) cellular vaccines can be delivered to the target lymphoid tissues and cells by nanocarriers and nanoplatforms to increase the potency and durability of antitumor immunity and minimize negative side effects. Nanovaccines use nanoparticles (NPs) as carriers and/or adjuvants, offering the advantages of optimal nanoscale size, high stability, ample antigen loading, high immunogenicity, tunable antigen presentation, increased retention in lymph nodes, and immunity promotion. To induce antitumor immunity, cancer vaccines rely on tumor antigens, which are administered in the form of entire cells, peptides, nucleic acids, extracellular vesicles (EVs), or cell membrane-encapsulated NPs. Ideal cancer vaccines stimulate both humoral and cellular immunity while overcoming tumor-induced immune suppression. Herein, we review the key properties of nanovaccines for cancer immunotherapy and highlight the recent advances in their development based on the structure and composition of various (including synthetic and semi (biogenic) nanocarriers. Moreover, we discuss tumor cell-derived vaccines (including those based on whole-tumor-cell components, EVs, cell membrane-encapsulated NPs, and hybrid membrane-coated NPs), nanovaccine action mechanisms, and the challenges of immunocancer therapy and their translation to clinical applications.

Immunogenic dead cells engineered by the sequential treatment of ultraviolet irradiation/cryo-shocking for lung-targeting delivery and tumor vaccination

Chemoimmunotherapy is a promising strategy in tumor treatments. In this study, immunogenic dead cells were engineered by the sequential treatment of live tumor cells with ultraviolet (UV) irradiation and cryo-shocking. The dead cells could serve as a lung-targeting vehicle and tumor vaccine after differential loading of the chemo-drug 10-hydroxycamptothecin (HCPT) and immune adjuvant Quillaja saponin-21 (QS-21) via physical absorption and chemical conjugation, respectively. After intravenous administration, the dead cells could be trapped in pulmonary capillaries and could fast release HCPT to enhance the drug accumulation in local tissues. Further, the immunogenic dead cells elicited antitumor immune responses together with the conjugated adjuvant QS-21 to achieve the elimination and long-term surveillance of tumor cells. In a lung tumor-bearing mice model, this drug-delivery system achieved synergistic antitumor efficacy and prolonged the survival of mice.

PEI-Based Nanoparticles for Tumor Immunotherapy via In Situ Antigen-Capture Triggered by Photothermal Therapy

Activating a tumor antigen-specific immune response is key to the success of tumor immunotherapy and the development of personalized antitumor therapy. Nanocarriers can capture, enrich, and protect in situ produced tumor antigens due to immunogenic cell death (ICD), thus enhancing the tumor-specific immune response. Developing multifunctional nanocarriers that combine multiple antigen capturing mechanisms is crucial to the activation of tumor-specific immune responses. In this study, polyethylenimine (PEI) was employed as a main building block to construct a series of multifunctional indocyanine green (ICG)-loaded nanoparticles to capture antigens via multiple mechanisms: electrostatic interactions with PEI, hydrophobic interactions with the thermosensitive segment (POEGMA300), and covalent bonding with the pyridyl disulfide (PDS) groups, respectively. Their capacity of ICD induction, tumor antigen-capture, and antitumor immune responses were evaluated. Both the intrinsic toxicity of PEI and the ICG-mediated photothermal effect were responsible for inducing ICD. The positively charged PEI segment exhibited the best antigen-capturing ability via electrostatic interactions, promoted bone marrow-derived dendritic cell maturation and CD8+ T cell proliferation, and elicited antitumor immune responses in vivo. PDS groups bonded antigens covalently and significantly contributed to the suppression of distant tumor growth. Although the thermosensitive hydrophobic polymer segment did not contribute positively to antigen capture or tumor growth inhibition, NPs containing all of the functional modules prolonged the survival of tumor-bearing mice more than other treatments. This study provides more chemical insights into the design of polymer-based in situ nanovaccines against cancer.

Tumor-derived systems as novel biomedical tools-turning the enemy into an ally

Cancer is a complex illness that presents significant challenges in its understanding and treatment. The classic definition, "a group of diseases characterized by the uncontrolled growth and spread of abnormal cells in the body," fails to convey the intricate interaction between the many entities involved in cancer. Recent advancements in the field of cancer research have shed light on the role played by individual cancer cells and the tumor microenvironment as a whole in tumor development and progression. This breakthrough enables the utilization of the tumor and its components as biological tools, opening new possibilities. This article delves deeply into the concept of "tumor-derived systems", an umbrella term for tools sourced from the tumor that aid in combatting it. It includes cancer cell membrane-coated nanoparticles (for tumor theranostics), extracellular vesicles (for tumor diagnosis/therapy), tumor cell lysates (for cancer vaccine development), and engineered cancer cells/organoids (for cancer research). This review seeks to offer a complete overview of the tumor-derived materials that are utilized in cancer research, as well as their current stages of development and implementation. It is aimed primarily at researchers working at the interface of cancer biology and biomedical engineering, and it provides vital insights into this fast-growing topic.

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.

Application of microneedles combined with dendritic cell-targeted nanovaccine delivery system in percutaneous immunotherapy for triple-negative breast cancer

This work aims at developing a strategy to activate the antigen-presenting cells to enhance the effect of immunotherapy in triple-negative breast cancer (TNBC) through the dissolving microneedle patch (DMNP). In present study, mannosylated chitosan (MCS) nanoparticles (NPs) were designed to target dendritic cells (DCs), and the immunotherapy effect was enhanced by the adjuvant Bacillus Calmette-Guerin polysaccharide (BCG-PSN), achieving the purpose of transdermal immunotherapy for TNBC. Vaccination studies with mice demonstrated that MCS NPs effectively induce DCs maturation in the tumor-draining lymph nodes to stimulate strong immune responses in TNBC. Overall, chitosan-based DMNPs with complex adjuvant constituted a new potent transdermal vaccine delivery platform capable of exploiting more DCs in the skin for effective immunization.

Nano-vaccines combining customized in situ anti-PD-L1 depot for enhanced tumor immunotherapy

Low response rate of immune checkpoint blockade (ICB) has limited its clinical application. A promising strategy to overcome this limitation is the use of therapeutic cancer vaccines, which aim to induce robust immune responses that synergize with ICB through immune enhancement and immune normalization strategies. Herein, we developed a combination immunotherapy by combining nano-vaccines consisting of whole tumor cell lysates/CpG liposomes (LCLs) with an anti-PD-L1 loaded lipid gel (aPD-L1@LG). The LCLs were fabricated using cationic liposomes, while the lipid gels (LGs) were prepared by using soybean phosphatidylcholine (SPC) and glycerol dioleate (GDO). Subcutaneous administration of LCLs successfully activated dendritic cells (DCs), and intratumoral administration of anti-PD-L1@LG ensured sustained ICB activity. These results demonstrated that this combination immunotherapy enhanced anti-tumor efficacy and prolonged the survival time in melanoma by activating systemic anti-tumor immune responses. These findings highlight the potential of this rational design as a promising strategy for tumor treatment.

Polymeric nanoparticles for DNA vaccine-based cancer immunotherapy: a review

Cancer is one of the leading causes of death and mortality in the world. There is an essential need to develop new drugs or therapeutic approaches to manage treatment-resistant cancers. Cancer immunotherapy is a type of cancer treatment that uses the power of the body's immune system to prevent, control, and eliminate cancer. One of the materials used as a vaccine in immunotherapy is DNA. The application of polymeric nanoparticles as carriers for DNA vaccines could be an effective therapeutic approach to activate immune responses and increase antigen presentation efficiency. Various materials have been used as polymeric nanoparticles, including: chitosan, poly (lactic-co-glycolic acid), Polyethylenimine, dendrimers, polypeptides, and polyesters. Application of these polymer nanoparticles has several advantages, including increased vaccine delivery, enhanced antigen presentation, adjuvant effects, and more sustainable induction of the immune system. Besides many clinical trials and commercial products that were developed based on polymer nanoparticles, there is still a need for more comprehensive studies to increase the DNA vaccine efficiency in cancer immunotherapy using this type of carrier.

Current Status and Trends in Nucleic Acids for Cancer Therapy: A Focus on Polysaccharide-Based Nanomedicines

The efficacious delivery of therapeutic nucleic acids to cancer still remains an open issue. Through the years, several strategies are developed for the encapsulation of genetic molecules exploiting different materials, such as viral vectors, lipid nanoparticles (LNPs), and polymeric nanoparticles (NPs). Indeed, the rapid approval by regulatory authorities and the wide use of LNPs complexing the mRNA coding for the spark protein for COVID-19 vaccination paved the way for the initiation of several clinical trials exploiting lipid nanoparticles for cancer therapy. Nevertheless, polymers still represent a valuable alternative to lipid-based formulations, due to the low cost and the chemical flexibility that allows for the conjugation of targeting ligands. This review will analyze the status of the ongoing clinical trials for cancer therapy, including vaccination and immunotherapy approaches, exploiting polymeric materials. Among those nanosized carriers, sugar-based backbones are an interesting category. A cyclodextrin-based carrier (CALAA-01) is the first polymeric material to enter a clinical trial complexed with siRNA for cancer therapy, and chitosan is one of the most characterized non-viral vectors able to complex genetic material. Finally, the recent advances in the use of sugar-based polymers (oligo- and polysaccharides) for the complexation of nucleic acids in advanced preclinical stage will be discussed.

Current status of nano-vaccinology in veterinary medicine science

Vaccination programmes provide a safe, effective and cost-efficient strategy for maintaining population health. In veterinary medicine, vaccination not only reduces disease within animal populations but also serves to enhance public health by targeting zoonoses. Nevertheless, for many pathogens, an effective vaccine remains elusive. Recently, nanovaccines have proved to be successful for various infectious and non-infectious diseases of animals. These novel technologies, such as virus-like particles, self-assembling proteins, polymeric nanoparticles, liposomes and virosomes, offer great potential for solving many of the vaccine production challenges. Their benefits include low immunotoxicity, antigen stability, enhanced immunogenicity, flexibility sustained release and the ability to evoke both humoral and cellular immune responses. Nanovaccines are more efficient than traditional vaccines due to ease of control and plasticity in their physio-chemical properties. They use a highly targeted immunological approach which can provide strong and long-lasting immunity. This article reviews the currently available nanovaccine technology and considers its utility for both infectious diseases and non-infectious diseases such as auto-immunity and cancer. Future research opportunities and application challenges from bench to clinical usage are also discussed.

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.

Targeting lymph node delivery with nanovaccines for cancer immunotherapy: recent advances and future directions

Although cancer immunotherapy is a compelling approach against cancer, its effectiveness is hindered by the challenge of generating a robust and durable immune response against metastatic cancer cells. Nanovaccines, specifically engineered to transport cancer antigens and immune-stimulating agents to the lymph nodes, hold promise in overcoming these limitations and eliciting a potent and sustained immune response against metastatic cancer cells. This manuscript provides an in-depth exploration of the lymphatic system's background, emphasizing its role in immune surveillance and tumor metastasis. Furthermore, it delves into the design principles of nanovaccines and their unique capability to target lymph node metastasis. The primary objective of this review is to provide a comprehensive overview of the current advancements in nanovaccine design for targeting lymph node metastasis, while also discussing their potential to enhance cancer immunotherapy. By summarizing the state-of-the-art in nanovaccine development, this review aims to shed light on the promising prospects of harnessing nanotechnology to potentiate cancer immunotherapy and ultimately improve patient outcomes.

Bone-derived MSCs encapsulated in alginate hydrogel prevent collagen-induced arthritis in mice through the activation of adenosine A2A/2B receptors in tolerogenic dendritic cells

Tolerogenic dendritic cells (tolDCs) facilitate the suppression of autoimmune responses by differentiating regulatory T cells (Treg). The dysfunction of immunotolerance results in the development of autoimmune diseases, such as rheumatoid arthritis (RA). As multipotent progenitor cells, mesenchymal stem cells (MSCs), can regulate dendritic cells (DCs) to restore their immunosuppressive function and prevent disease development. However, the underlying mechanisms of MSCs in regulating DCs still need to be better defined. Simultaneously, the delivery system for MSCs also influences their function. Herein, MSCs are encapsulated in alginate hydrogel to improve cell survival and retention in situ, maximizing efficacy in vivo. The three-dimensional co-culture of encapsulated MSCs with DCs demonstrates that MSCs can inhibit the maturation of DCs and the secretion of pro-inflammatory cytokines. In the collagen-induced arthritis (CIA) mice model, alginate hydrogel encapsulated MSCs induce a significantly higher expression of CD39⁺CD73⁺ on MSCs. These enzymes hydrolyze ATP to adenosine and activate A_2A/2B receptors on immature DCs, further promoting the phenotypic transformation of DCs to tolDCs and regulating naïve T cells to Tregs. Therefore, encapsulated MSCs obviously alleviate the inflammatory response and prevent CIA progression. This finding clarifies the mechanism of MSCs-DCs crosstalk in eliciting the immunosuppression effect and provides insights into hydrogel-promoted stem cell therapy for autoimmune diseases.

Biomaterials Facilitating Dendritic Cell-Mediated Cancer Immunotherapy

Dendritic cell (DC)-based cancer immunotherapy has exhibited remarkable clinical prospects because DCs play a central role in initiating and regulating adaptive immune responses. However, the application of traditional DC-mediated immunotherapy is limited due to insufficient antigen delivery, inadequate antigen presentation, and high levels of immunosuppression. To address these challenges, engineered biomaterials have been exploited to enhance DC-mediated immunotherapeutic effects. In this review, vital principal components that can enhance DC-mediated immunotherapeutic effects are first introduced. The parameters considered in the rational design of biomaterials, including targeting modifications, size, shape, surface, and mechanical properties, which can affect biomaterial optimization of DC functions, are further summarized. Moreover, recent applications of various engineered biomaterials in the field of DC-mediated immunotherapy are reviewed, including those serve as immune component delivery platforms, remodel the tumor microenvironment, and synergistically enhance the effects of other antitumor therapies. Overall, the present review comprehensively and systematically summarizes biomaterials related to the promotion of DC functions; and specifically focuses on the recent advances in biomaterial designs for DC activation to eradicate tumors. The challenges and opportunities of treatment strategies designed to amplify DCs via the application of biomaterials are discussed with the aim of inspiring the clinical translation of future DC-mediated cancer immunotherapies.

CD16 CAR-T cells enhance antitumor activity of CpG ODN-loaded nanoparticle-adjuvanted tumor antigen-derived vaccinevia ADCC approach

BACKGROUND

Combinatorial immunotherapy strategies for enhancing the responsiveness of immune system have shown great promise for cancer therapy. Engineered nanoformulation incorporated toll-like receptor (TLR) 9 agonist CpG ODN has shown more positive results in suppressing tumor growth and can significantly enhance other immunotherapy activity with combinatorial effects due to the innate and adaptive immunostimulatory effects of CpG.

RESULTS

In the present work, protamine sulfate (PS) and carboxymethyl β-glucan (CMG) were used as nanomaterials to form nanoparticles through a self-assembly approach for CpG ODN encapsulation to generate CpG ODN-loaded nano-adjuvant (CNPs), which was subsequently mixed with the mixture of mouse melanoma-derived antigens of tumor cell lysates (TCL) and neoantigens to develop vaccine for anti-tumor immunotherapy. The obtained results showed that CNPs was able to effectively deliver CpG ODN into murine bone marrow-derived dendritic cells (DC) in vitro, and remarkably stimulate the maturation of DC cells with proinflammatory cytokine secretion. In addition, in vivo analysis showed that CNPs enhanced anti-tumor activity of PD1 antibody and CNPs-adjuvanted vaccine based on the mixture antigens of melanoma TCL and melanoma-specific neoantigen could not only induce anti-melanoma cellular immune responses, but also elicit melanoma specific humoral immune responses, which significantly inhibited xenograft tumor growth. Furthermore, CD16 CAR-T cells were generated by expressing CD16-CAR in CD3⁺CD8⁺ murine T cells.

CONCLUSION

Our results eventually showed that anti-melanoma antibodies induced by CNPs-adjuvanted TCL vaccines were able to collaborate with CD16-CAR-T cells to generate an enhanced targeted anti-tumor effects through ADCC (antibody dependent cell cytotoxicity) approach. CD16 CAR-T cells has thus a great potential to be an universal promising strategy targeting on solid tumor synergistic immunotherapy via co-operation with TCL-based vaccine.

Computational and Experimental Evaluation of the Immune Response of Neoantigens for Personalized Vaccine Design

In the last few years, the importance of neoantigens in the development of personalized antitumor vaccines has increased remarkably. In order to study whether bioinformatic tools are effective in detecting neoantigens that generate an immune response, DNA samples from patients with cutaneous melanoma in different stages were obtained, resulting in a total of 6048 potential neoantigens gathered. Thereafter, the immunological responses generated by some of those neoantigens ex vivo were tested, using a vaccine designed by a new optimization approach and encapsulated in nanoparticles. Our bioinformatic analysis indicated that no differences were found between the number of neoantigens and that of non-mutated sequences detected as potential binders by IEDB tools. However, those tools were able to highlight neoantigens over non-mutated peptides in HLA-II recognition (p-value 0.03). However, neither HLA-I binding affinity (p-value 0.08) nor Class I immunogenicity values (p-value 0.96) indicated significant differences for the latter parameters. Subsequently, the new vaccine, using aggregative functions and combinatorial optimization, was designed. The six best neoantigens were selected and formulated into two nanoparticles, with which the immune response ex vivo was evaluated, demonstrating a specific activation of the immune response. This study reinforces the use of bioinformatic tools in vaccine development, as their usefulness is proven both in silico and ex vivo.

Autologous-cancer-cryoablation-mediated nanovaccine augments systematic immunotherapy

Cancer vaccines developed from autologous tumors hold tremendous promise for individualized cancer immunotherapy. Cryoablation-induced in situ autologous antigens are capable of activating systemic immunity with low damage. However, the dissipation of cancer fragments after cryoablation induces poor immunogenicity and short-time maintenance of immunological memory. To solve this challenge, a nanovaccine with functional grippers is proposed to largely enhance the in situ grasping of tumor fragments, combined with an immune adjuvant to further strengthen the immune-therapeutic effect. Herein, maleimide-modified Pluronic F127-chitosan nanoparticles encapsulating Astragalus polysaccharide (AMNPs) are developed. The AMNPs can capture multifarious and immunogenic tumor antigens generated through cryoablation, specifically target lymph nodes and facilitate lysosome escape to activate remote dendritic cells, and modulate T cell differentiation through cross-presentation, thereby breaking the immunosuppressive microenvironment to achieve durable and robust tumor-specific immunity. In the bilateral Lewis lung cancer tumor model, AMNP-mediated cryoablation can significantly regress primary tumors (with a tumor growth inhibition rate of 100%, and a recurrence rate of 0% (30 days) and 16.67% (60 days)), inhibit untreated abscopal tumor growth (a decrease of about 3.84-fold compared with the saline group), and ultimately improve the long-term survival rate (83.33%). Collectively, the development of a lymph-node-targeted in situ cancer-cryoablation-mediated nanovaccine provides a promising approach for personalized cancer immunotherapy against metastatic cancers.

Current and emerging applications of saccharide-modified chitosan: a critical review

Chitin, as the main component of the exoskeleton of Arthropoda, is a highly available natural polymer that can be processed into various value-added products. Its most important derivative, i.e., chitosan, comprising β-1,4-linked 2-amino-2-deoxy-β-d-glucose (deacetylated d-glucosamine) and N-acetyl-d-glucosamine units, can be prepared via alkaline deacetylation process. Chitosan has been used as a biodegradable, biocompatible, non-antigenic, and nontoxic polymer in some in-vitro applications, but the recently found potentials of chitosan for in-vivo applications based on its biological activities, especially antimicrobial, antioxidant, and anticancer activities, have upgraded the chitosan roles in biomaterials. Chitosan approval, generally recognized as a safe compound by the United States Food and Drug Administration, has attracted much attention toward its possible applications in diverse fields, especially biomedicine and agriculture. Even with some favorable characteristics, the chitosan's structure should be customized for advanced applications, especially due to its drawbacks, such as low drug-load capacity, low solubility, high viscosity, lack of elastic properties, and pH sensitivity. In this context, derivatization with relatively inexpensive and highly available mono- and di-saccharides to soluble branched chitosan has been considered a "game changer". This review critically reviews the emerging technologies based on the synthesis and application of lactose- and galactose-modified chitosan as two important chitosan derivatives. Some characteristics of chitosan derivatives and biological activities have been detailed first to understand the value of these natural polymers. Second, the saccharide modification of chitosan has been discussed briefly. Finally, the applications of lactose- and galactose-modified chitosan have been scrutinized and compared to native chitosan to provide an insight into the current state-of-the research for stimulating new ideas with the potential of filling research gaps.

Advanced Biomaterials with Intrinsic Immunomodulation Effects for Cancer Immunotherapy

In recent years, tumor immunotherapy has achieved significant success in tumor treatment based on immune checkpoint blockers and chimeric antigen receptor T-cell therapy. However, about 70-80% of patients with solid tumors do not respond to immunotherapy due to immune evasion. Recent studies found that some biomaterials have intrinsic immunoregulatory effects, except serve as carriers for immunoregulatory drugs. Moreover, these biomaterials have additional advantages such as easy functionalization, modification, and customization. In this review, the recent advances of these immunoregulatory biomaterials in cancer immunotherapy and their interaction with cancer cells, immune cells, and the immunosuppressive tumor microenvironment are summarized. Finally, the opportunities and challenges of immunoregulatory biomaterials used in the clinic and the prospect of their future in cancer immunotherapy are discussed.

Biomimetic nanoparticles for DC vaccination: a versatile approach to boost cancer immunotherapy

Cancer immunotherapy, which harnesses the immune system to fight cancer, has begun to make a breakthrough in clinical applications. Dendritic cells (DCs) are the bridge linking innate and adaptive immunity and the trigger of tumor immune response. Considering the cumbersome process and poor efficacy of classic DC vaccines, there has been interest in transferring the field of in vitro-generated DC vaccines to nanovaccines. Conventional nanoparticles have insufficient targeting ability and are easily cleared by the reticuloendothelial system. Biological components have evolved very specific functions, which are difficult to fully reproduce with synthetic materials, making people interested in using the further understanding of biological systems to prepare nanoparticles with new and enhanced functions. Biomimetic nanoparticles are semi-biological or nature-derived delivery systems comprising one or more natural materials, which have a long circulation time in vivo and excellent performance of targeting DCs, and can mimic the antigen-presenting behavior of DCs. In this review, we introduce the classification, design, preparation, and challenges of different biomimetic nanoparticles, and discuss their application in activating DCs in vivo and stimulating T cell antitumor immunity. Incorporating biomimetic nanoparticles into cancer immunotherapy has shown outstanding advantages in precisely coaxing the immune system against cancer.

Comparison of tumor-derived total RNA and cell lysate on antitumor immune activity

Tumor-derived total RNA (TdRNA) and cell lysate (TCL), with almost all the relevant tumor antigens, represent attractive alternative sources of antigens in antitumor immunotherapy. However, the comparison of their capacity to elicit immune responses against breast cancer is still lacking. In this study, the antitumor immune effects of TdRNA and TCL were systematically compared. We isolated TdRNA and TCL from 4T1 mouse breast cancer cells, and found that both sources of antigens could stimulate the maturation of dendritic cells (DCs) at the cellular and in vivo levels, and induce robust cellular immune responses, as evidenced by the increased percentages of both CD4⁺ and CD8⁺ T cells in the inguinal lymph nodes and spleen. But TdRNA performed stronger immunoactivities than TCL on the increase of T cell population through DCs activation. Additionally, the synergistic antitumor efficacy of paclitaxel (PTX) with TdRNA and TCL respectively was further evaluated in the murine 4T1 tumor model. Compared with TCL, TdRNA could inhibit tumor growth more effectively with low systemic toxicity when combined with PTX, which was, at least in part, attributable to the improvement of systemic immune function and tumor immune infiltration. Overall, TdRNA outperforms TCL in antitumor immunity, and is expected to be a promising candidate for application as the source of tumor antigens.

Sustained release of tumor cell lysate and CpG from an injectable, cytotoxic hydrogel for melanoma immunotherapy

Many basic research studies have shown the potential of autologous cancer vaccines in the treatment of melanoma. However, some clinical trials showed that simplex whole tumor cell vaccines can only elicit weak CD8⁺ T cell-mediated antitumor responses which were not enough for effective tumor elimination. So efficient cancer vaccine delivery strategies with improved immunogenicity are needed. Herein, we described a novel hybrid vaccine "MCL" (Melittin-RADA₃₂-CpG-Lysate) which was composed of melittin, RADA₃₂, CpG and tumor lysate. In this hybrid vaccine, antitumor peptide melittin and self-assembling fusion peptide RADA₃₂ were assembled to form the hydrogel framework melittin-RADA₃₂(MR). Then, whole tumor cell lysate and immune adjuvant CpG-ODN were loaded into MR to develop an injectable and cytotoxic hydrogel MCL. MCL showed excellent ability for sustained drug release, to activate dendritic cells and directly kill melanoma cells in vitro. In vivo, MCL not only exerted direct antitumor activity, but also had robust immune initiation effects including the activation of dendritic cells in draining lymph nodes and the infiltration of cytotoxic T lymphocytes (CTLs) in tumor microenvironment. In addition, MCL can efficiently inhibit melanoma growth in B16-F10 tumor bearing mice, which suggested that MCL is a potential cancer vaccine strategy for melanoma treatment.

Dendritic cell-targeting polymer nanoparticle-based immunotherapy for cancer: A review

Cancer immunity is dependent on dynamic interactions between T cells and dendritic cells (DCs). Polymer-based nanoparticles target DC receptors to improve anticancer immune responses. In this paper, DC surface receptors and their specific coupling natural ligands and antibodies are reviewed and compared. Moreover, reaction mechanisms are described, and the synergistic effects of immune adjuvants are demonstrated. Also, extracellular-targeting antigen-delivery strategies and intracellular stimulus responses are reviewed to promote the rational design of polymer delivery systems.

Chitosan nanocarriers containing essential oils as a green strategy to improve the functional properties of chitosan: A review

Large amounts of agricultural waste, especially marine product waste, are produced annually. These wastes can be used to produce compounds with high-added value. Chitosan is one such valuable product that can be obtained from crustacean wastes. Various biological activities of chitosan and its derivatives, especially antimicrobial, antioxidant, and anticancer properties, have been confirmed by many studies. The unique characteristics of chitosan, especially chitosan nanocarriers, have led to the expansion of using chitosan in various sectors, especially in biomedical sciences and food industries. On the other hand, essential oils, known as volatile and aromatic compounds of plants, have attracted the attention of researchers in recent years. Like chitosan, essential oils have various biological activities, including antimicrobial, antioxidant, and anticancer. In recent years, one of the ways to improve the biological properties of chitosan is to use essential oils encapsulated in chitosan nanocarriers. Among the various biological activities of chitosan nanocarriers containing essential oils, most studies conducted in recent years have been in the field of antimicrobial activity. It was documented that the antimicrobial activity was increased by reducing the size of chitosan particles in the nanoscale. In addition, the antimicrobial activity was intensified when essential oils were in the structure of chitosan nanoparticles. Essential oils can increase the antimicrobial activity of chitosan nanoparticles with synergistic effects. Using essential oils in the structure of chitosan nanocarriers can also improve the other biological properties (antioxidant and anticancer activities) of chitosan and increase the application fields of chitosan. Of course, using essential oils in chitosan nanocarriers for commercial use requires more studies, including stability during storage and effectiveness in real environments. This review aims to overview recent studies on the biological effects of essential oils encapsulated in chitosan nanocarriers, with notes on their biological mechanisms.

Immunomodulatory nanosystems: An emerging strategy to combat viral infections

The viral infection spreads with the assistance of a host. Traditional antiviral therapies cannot provide long-term immunity against emerging and drug-resistant viral infections. Immunotherapy has evolved as an efficient approach for disease prevention and treatment, which include cancer, infections, inflammatory, and immune disorders. Immunomodulatory nanosystems can dramatically enhance therapeutic outcomes by combating many therapeutic challenges, such as poor immune stimulation and off-target adverse effects. Recently, immunomodulatory nanosystems have emerged as a potent antiviral strategy to intercept viral infections effectively. This review introduces major viral infections with their primary symptoms, route of transmission & targeted organ, and different stages of the viral life cycle with respective traditional blockers. The IMNs have an exceptional capacity for precisely modulating the immune system for therapeutic applications. The nano sized immunomodulatory systems permit the immune cells to interact with infectious agents enhancing lymphatic drainage and endocytosis by the over-reactive immune cells in the infected areas. Immune cells that can be modulated upon viral infection via various immunomodulatory nanosystems have been discussed. Advancement in theranostics can yield an accurate diagnosis, adequate treatment, and real-time screening of viral infections. Nanosystem-based drug delivery can continue to thrive in diagnosing, treating, and preventing viral infections. The curative medicine for remerging and drug-resistant viruses remains challenging, though certain systems have expanded our perception and initiated a new research domain in antiviral treatments.

A Review on Recent Advances in Mannose-Functionalized Targeted Nanocarrier Delivery Systems in Cancer and Infective Therapeutics

Unmodified nanocarriers used in the chemotherapy of cancers and various infectious diseases exhibit prolonged blood circulation time, prevent enzymatic degradation and increase chemical stability of encapsulated therapeutics. However, off-target effect and lack of specificity associated with unmodified nanoparticles (NPs) limit their applications in the health care system. Mannose (Man) receptors with significant overexpression on antigen-presenting cells and macrophages are among the most admired targets for cancer and anti-infective therapeutics. Therefore, development of Man functionalized nanocarriers targeting Man receptors, for target specific drug delivery in the chemotherapy have been extensively studied. Present review expounds diverse Man-conjugated NPs with their potential for targeted drug delivery, improved biodistribution profiles and localization. Additionally, the review gives detailed account of the interactions of mannosylated NPs with various biological systems and their characterization not discussed in earlier published reports is discussed.

Chitin and Chitosan as Polymers of the Future-Obtaining, Modification, Life Cycle Assessment and Main Directions of Application

Natural polymers are very widespread in the world, which is why it is so important to know about the possibilities of their use. Chitin is the second most abundant reproducible natural polymer in nature; however, it is insoluble in water and basic solvents. Chitin is an unused waste of the food industry, for which there are possibilities of secondary management. The research led to obtaining a soluble, environmentally friendly form of chitin, which has found potential applications in the many fields, e.g., medicine, cosmetics, food and textile industries, agriculture, etc. The deacetylated form of chitin, which is chitosan, has a number of beneficial properties and wide possibilities of modification. Modification possibilities mean that we can obtain chitosan with the desired functional properties, facilitating, for example, the processing of this polymer and expanding the possibilities of its application, also as biomimetic materials. The review contains a rich description of the possibilities of modifying chitin and chitosan and the main directions of their application, and life cycle assessment (LCA)-from the source of the polymer through production materials to various applications with the reduction of waste.

Liposomal celecoxib combined with dendritic cell therapy enhances antitumor efficacy in melanoma

Cancer vaccine efficacy is limited by the immunosuppressive nature of the tumor microenvironment created by inflammation, immune inhibitory factors, and regulatory T cells (Tregs). Inspired by the role of cyclooxygenase-2 (COX-2) in inflammation in the tumor site, we proposed that normalization of the tumor microenvironment by celecoxib as a COX-2 inhibitor might improve the efficacy of Dendritic Cell (DC) therapy in a melanoma model. In the present study, liposomal celecoxib (Lip-CLX) was combined with ex vivo generated DC vaccines pulsed with gp100 peptide (in liposomal and non-liposomal forms) for prophylactic and therapeutic evaluation in the B16F10 melanoma model. Tumor site analysis by flow cytometry demonstrated that intravenous administration of Lip-CLX at a dose of 1 mg/kg in four doses effectively normalized the tumor microenvironment by reducing Tregs and IL-10 production. Furthermore, in combination with DC vaccination (DC + Lip-peptide+Lip-CLX), it significantly increased tumor-infiltrating CD4⁺ and CD8⁺ T cells and secretion of IFN-γ. This combinatorial strategy produced an effective prophylactic and therapeutic antitumor response, which reduced tumor growth and prolonged the overall survival. In conclusion, our findings suggest that the liposomal celecoxib targets the inhibitory mechanisms of the tumor microenvironment and broadens the impact of DC therapy to improve the outcome of immunotherapy in solid tumors.

Enhancedanti-tumor efficacy through a combination of intramuscularly expressed DNA vaccine and plasmid-encoded PD-1 antibody

Immune check inhibitors (ICIs) have moderate response rates (~20%-30%) in some malignancies clinically, and, when used in combination with other immunotherapeutic strategies such as DNA tumor vaccines, there is evidence to suggest that they could optimize the efficacy of cancer treatment. In this study, we validated that intramuscular injection of plasmid DNA (pDNA) encoding OVA combined with pDNA encoding α-PD-1 (abbreviated as α-PD-1 in the following treatment groups) may enhance therapeutic efficacy by means of in situ gene delivery and enhanced muscle-specific potent promoter. Mice treated with pDNA-OVA or pDNA-α-PD-1 alone showed weak tumor inhibition in the MC38-OVA-bearing model. In comparison, the combined treatment of pDNA-OVA and pDNA-α-PD-1 resulted in superior tumor growth inhibition and a significantly improved survival rate of over 60% on day 45. In the B16-F10-OVA metastasis model, the addition of the DNA vaccine enhanced resistance to tumor metastasis and increased the populations of CD8⁺ T cells in blood and spleen. In conclusion, the current research shows that a combination of pDNA-encoded PD-1 antibody and DNA vaccine expressed in vivo is an efficient, safe, and economical strategy for tumor therapy.

An Integrated Polymeric mRNA Vaccine without Inflammation Side Effects for Cellular Immunity Mediated Cancer Therapy

Among the few available mRNA delivery vehicles, lipid nanoparticles (LNPs) are the most clinically advanced but they require cumbersome four components and suffer from inflammation-related side effects that should be minimized for safety. Yet, a certain level of proinflammatory responses and innate immune activation are required to evoke T-cell immunity for mRNA cancer vaccination. To address these issues and develop potent yet low-inflammatory mRNA cancer vaccine vectors, a series of alternating copolymers "PHTA" featured with ortho-hydroxy tertiary amine (HTA) repeating units for mRNA delivery is synthesized, which can play triple roles of condensing mRNA, enhancing the polymeric nanoparticle (PNP) stability, and prolonging circulation time. Unlike LNPs exhibiting high levels of inflammation, the PHTA-based PNPs show negligible inflammatory side effects in vivo. Importantly, the top candidate PHTA-C18 enables successful mRNA cancer vaccine delivery in vivo and leads to a robust CD8⁺ T cell mediated antitumor cellular immunity. Such PHTA-based integrated PNP provides a potential approach for establishing mRNA cancer vaccines with good inflammatory safety profiles.

Highly sensitive H2O2-scavenging nano-bionic system for precise treatment of atherosclerosis

In atherosclerosis, chronic inflammatory processes in local diseased areas may lead to the accumulation of reactive oxygen species (ROS). In this study, we devised a highly sensitive H₂O₂-scavenging nano-bionic system loaded with probucol (RPP-PU), to treat atherosclerosis more effectively. The RPP material had high sensitivity to H₂O₂, and the response sensitivity could be reduced from 40 to 10 μmol/L which was close to the lowest concentration of H₂O₂ levels of the pathological environment. RPP-PU delayed the release and prolonged the duration of PU in vivo. In Apolipoprotein E deficient (ApoE^‒/‒) mice, RPP-PU effectively eliminated pathological ROS, reduced the level of lipids and related metabolic enzymes, and significantly decreased the area of vascular plaques and fibers. Our study demonstrated that the H₂O₂-scavenging nano-bionic system could scavenge the abundant ROS in the atherosclerosis lesion, thereby reducing the oxidative stress for treating atherosclerosis and thus achieve the therapeutic goals with atherosclerosis more desirably.

Enhanced Anti-Proliferative Effect of Carboplatin in Ovarian Cancer Cells Exploiting Chitosan-Poly (Lactic Glycolic Acid) Nanoparticles

OBJECTIVE

The present article aimed to enhance the therapeutic efficacy of carboplatin (CP) using the formulation of chitosan-poly (lactic glycolic acid) nanoparticles (CS-PLGA NPs).

METHODS

Nanoparticles were synthesized by an ionic gelation method and were characterized for their morphology, particle size, and surface potential measurements by TEM and zeta sizer. This study was highlighted for the evaluation of drug entrapment, loading and in vitro drug release capabilities of the prepared nanoparticles by spectrophotometric analysis. The stability study was also conducted after 3 months for their particle size, zeta potential, drug loading and encapsulation efficiencies. Further, ovarian cancer cell line PEO1 was used to evaluate the toxicity and efficacy of nano-formulation by MTT assay. Additionally, the study was evaluated for apoptosis using flow cytometric analysis.

RESULTS

The CS-PLGA-CP NPs were uniform and spherical in shape. The particle size and zeta potential of CS-PLGA-CP NPs were measured to be 156 ±6.8 nm and +52 ±2.4 mV, respectively. High encapsulation (87.4 ± 4.5%) and controlled retention capacities confirmed the efficiency of the prepared nanoparticles in a time and dose-dependent manner. The cytotoxicity assay results also showed that CS-PLGA-CP NPs have a high efficiency on PEO1 cells compared to the free drug. The flow cytometric result showed 64.25% of the PEO1 cells were apoptotic, and 8.42% were necrotic when treated with CS-PLGA-CP NPs.

CONCLUSION

Chitosan-PLGA combinational polymeric nanoparticles were not only steady but also non-toxic. Our experiments revealed that the chitosan-PLGA nanoparticles could be used as a challenging vehicle candidate for drug delivery for the therapeutic treatment of ovarian cancer.

Locoregional Lymphatic Delivery Systems Using Nanoparticles and Hydrogels for Anticancer Immunotherapy

The lymphatic system has gained significant interest as a target tissue to control cancer progress, which highlights its central role in adaptive immune response. Numerous mechanistic studies have revealed the benefits of nano-sized materials in the transport of various cargos to lymph nodes, overcoming barriers associated with lymphatic physiology. The potential of sustained drug delivery systems in improving the therapeutic index of various immune modulating agents is also being actively discussed. Herein, we aim to discuss design rationales and principles of locoregional lymphatic drug delivery systems for invigorating adaptive immune response for efficient antitumor immunotherapy and provide examples of various advanced nanoparticle- and hydrogel-based formulations.

Engineered tumor cell-derived vaccines against cancer: The art of combating poison with poison

Tumor vaccination is a promising approach for tumor immunotherapy because it presents high specificity and few side effects. However, tumor vaccines that contain only a single tumor antigen can allow immune system evasion by tumor variants. Tumor antigens are complex and heterogeneous, and identifying a single antigen that is uniformly expressed by tumor cells is challenging. Whole tumor cells can produce comprehensive antigens that trigger extensive tumor-specific immune responses. Therefore, tumor cells are an ideal source of antigens for tumor vaccines. A better understanding of tumor cell-derived vaccines and their characteristics, along with the development of new technologies for antigen delivery, can help improve vaccine design. In this review, we summarize the recent advances in tumor cell-derived vaccines in cancer immunotherapy and highlight the different types of engineered approaches, mechanisms, administration methods, and future perspectives. We discuss tumor cell-derived vaccines, including whole tumor cell components, extracellular vesicles, and cell membrane-encapsulated nanoparticles. Tumor cell-derived vaccines contain multiple tumor antigens and can induce extensive and potent tumor immune responses. However, they should be engineered to overcome limitations such as insufficient immunogenicity and weak targeting. The genetic and chemical engineering of tumor cell-derived vaccines can greatly enhance their targeting, intelligence, and functionality, thereby realizing stronger tumor immunotherapy effects. Further advances in materials science, biomedicine, and oncology can facilitate the clinical translation of tumor cell-derived vaccines.

Targeting dendritic cells with TLR-2 ligand-coated nanoparticles loaded with Mycobacterium tuberculosis epitope induce antituberculosis immunity

Novel vaccination strategies are crucial to efficiently control tuberculosis, as proposed by the World Health Organization under its flagship program "End TB Strategy." However, the emergence of drug-resistant strains of Mycobacterium tuberculosis (Mtb), particularly in those coinfected with HIV-AIDS, constitutes a major impediment to achieving this goal. We report here a novel vaccination strategy that involves synthesizing a formulation of an immunodominant peptide derived from the Acr1 protein of Mtb. This nanoformulation in addition displayed on the surface a toll-like receptor-2 ligand to offer to target dendritic cells (DCs). Our results showed an efficient uptake of such a concoction by DCs in a predominantly toll-like receptor-2-dependent pathway. These DCs produced elevated levels of nitric oxide, proinflammatory cytokines interleukin-6, interleukin-12, and tumor necrosis factor-α, and upregulated the surface expression of major histocompatibility complex class II molecules as well as costimulatory molecules such as CD80 and CD86. Animals injected with such a vaccine mounted a significantly higher response of effector and memory Th1 cells and Th17 cells. Furthermore, we noticed a reduction in the bacterial load in the lungs of animals challenged with aerosolized live Mtb. Therefore, our findings indicated that the described vaccine triggered protective anti-Mtb immunity to control the tuberculosis infection.

Synergy of Polydopamine Nanovaccine and Endostar Alginate Hydrogel for Improving Antitumor Immune Responses Against Colon Tumor

BACKGROUND

Tumor immunotherapy, a novel type of therapeutic treatment, has a wide range of applications with potentially prolonged benefits. However, current immunotherapy has a low overall response rate in treating a variety of tumors. Combination of immunotherapy with other therapies can improve the therapeutic response rates. The purpose of this work was to explore the potential of anti-angiogenic treatment in combination with tumor cell lysate loaded polydopamine nanoparticle vaccine as a therapeutic strategy for colon tumor.

METHODS

We grafted tumor cell lysate onto polydopamine nanoparticles as nano-vaccine (TCLN) and fabricated alginate hydrogel loaded with Endostar (EH), then detected characteristics of EH and TCLN. We also estimated the cytotoxicity of EH/TCLN in vitro. In the tumor-bearing mouse model, we evaluated the antitumor effect of EH/TCLN treatment, and developed the animal survival study. After performing the EH/TCLN treatment, we also analyzed T cells and DCs using flow cytometry, and determined T cell responses and tumor microenvironmental cytokines. At last, we assessed the effect of the EH/TCLN treatment on anti-angiogenesis further.

RESULTS

When applied in combination with TCLN in MC-38 tumor-bearing mice, EH/TCLN significantly suppressed tumor growth with more than half of the mice showing tumor regression. In addition, EH/TCLN treatment resulted in noticeable changes in the tumor microenvironment. As compared with the control group, EH/TCLN treatment led to significantly reduced tumor angiogenesis and expression of tumor microenvironment-related cytokines (TMCs), increased proportion of CD8⁺ T cells in the spleen, lymph node and tumor, elevated activity of cytotoxic T lymphocytes (CTLs) and tumor cell apoptosis.

CONCLUSION

The present study demonstrated that the EH/TCLN treatment effectively created a favorable immune microenvironment for the induction of antitumor immunity and improved antitumor immune responses.

Lymph node-targeting nanovaccines for cancer immunotherapy

Cancer immunotherapies such as tumor vaccines, chimeric antigen receptor T cells and immune checkpoint blockades, have attracted tremendous attention. Among them, tumor vaccines prime immune response by delivering antigens and adjuvants to the antigen presenting cells (APCs), thus enhancing antitumor immunotherapy. Despite tumor vaccines have made considerable achievements in tumor immunotherapy, it remains challenging to efficiently deliver tumor vaccines to activate the dendritic cells (DCs) in lymph nodes (LNs). Rational design of nanovaccines on the basis of biomedical nanotechnology has emerged as one of the most promising strategies for boosting the outcomes of cancer immunotherapy. In recent years, great efforts have been made in exploiting various nanocarrier-based LNs-targeting tumor nanovaccines. In view of the rapid advances in this field, we here aim to summarize the latest progression in LNs-targeting nanovaccines for cancer immunotherapy, with special attention to various nano-vehicles developed for LNs-targeting delivery of tumor vaccines, including lipid-based nanoparticles, polymeric nanocarriers, inorganic nanocarriers and biomimetic nanosystems. Moreover, the recent trends in nanovaccines-based combination cancer immunotherapy are provided. Finally, the rationality, advantages and challenges of LNs-targeting nanovaccines for clinical translation and application are spotlighted.