Self-adjuvanted nanovaccine for cancer immunotherapy: Role of lysosomal rupture-induced ROS in MHC class I antigen presentation

Nanoparticles as Smart Carriers for Enhanced Cancer Immunotherapy

Cancer immunotherapy has emerged as a promising strategy for the treatment of many forms of cancer by stimulating body's own immune system. This therapy not only eradicates tumor cells by inducing strong anti-tumor immune response but also prevent their recurrence. The clinical cancer immunotherapy faces some insurmountable challenges including high immune-mediated toxicity, lack of effective and targeted delivery of cancer antigens to immune cells and off-target side effects. However, nanotechnology offers some solutions to overcome those limitations, and thus can potentiate the efficacy of immunotherapy. This review focuses on the advancement of nanoparticle-mediated delivery of immunostimulating agents for efficient cancer immunotherapy. Here we have outlined the use of the immunostimulatory nanoparticles as a smart carrier for effective delivery of cancer antigens and adjuvants, type of interactions between nanoparticles and the antigen/adjuvant as well as the factors controlling the interaction between nanoparticles and the receptors on antigen presenting cells. Besides, the role of nanoparticles in targeting/activating immune cells and modulating the immunosuppressive tumor microenvironment has also been discussed extensively. Finally, we have summarized some theranostic applications of the immunomodulatory nanomaterials in treating cancers based on the earlier published reports.

Nanomaterials for oncotherapies targeting the hallmarks of cancer

An increasing amount of evidence has demonstrated the diverse functionalities of nanomaterials in oncotherapies such as drug delivery, imaging, and killing cancer cells. This review aims to offer an authoritative guide for the development of nanomaterial-based oncotherapies and shed light on emerging yet understudied hallmarks of cancer where nanoparticles can help improve cancer control. With this aim, three nanomaterials, i.e. those based on gold, graphene, and liposome, were selected to represent and encompass metal inorganic, nonmetal inorganic, and organic nanomaterials, and four oncotherapies, i.e. phototherapies, immunotherapies, cancer stem cell therapies, and metabolic therapies, were characterized based on the differential hallmarks of cancer that they target. We also view physical plasma as a cocktail of reactive species and carrier of nanomaterials and focus on its roles in targeting the hallmarks of cancer provided with its unique traits and ability to selectively induce epigenetic and genetic modulations in cancer cells that halt tumor initiation and progression. This review provides a clear understanding of how the physico-chemical features of particles at the nanoscale contribute alone or create synergistic effects with current treatment modalities in combating each of the hallmarks of cancer that ultimately leads to desired therapeutic outcomes and shapes the toolbox for cancer control.

GSH depletion liposome adjuvant for augmenting the photothermal immunotherapy of breast cancer

The high redox level of tumor microenvironment inhibits the oxidation treatment and the immune response. Here, we innovatively develop maleimide liposome (ML) adjuvants to promote immunogenic cell death (ICD) induction and dendritic cells (DCs) maturation by glutathione (GSH) depletion for augmenting the photothermal immunotherapy of breast cancer. The ML effectively depletes the intracellular GSH and up-regulates reactive oxygen species (ROS) in both tumor cells and DCs. In tumor cells, the ROS boosted the ABTS·⁺ production to activate photothermal-induced ICD. In DCs, it relieved the immunosuppression, promoting DC maturation (57%) and antigen presenting. As a result of the ML assistant, the therapeutic systems improved the infiltration of CD8⁺ T cells to 53% in tumor tissues, eliciting strong abscopal effect and antimetastasis effect. The MLs were believed to be a superior candidate of adjuvants for enhancing immune response and cancer therapeutic efficacy.

pH-Responsive Nanoparticles for Cancer Immunotherapy: A Brief Review

Immunotherapy has recently become a promising strategy for the treatment of a wide range of cancers. However, the broad implementation of cancer immunotherapy suffers from inadequate efficacy and toxic side effects. Integrating pH-responsive nanoparticles into immunotherapy is a powerful approach to tackle these challenges because they are able to target the tumor tissues and organelles of antigen-presenting cells (APCs) which have a characteristic acidic microenvironment. The spatiotemporal control of immunotherapeutic drugs using pH-responsive nanoparticles endows cancer immunotherapy with enhanced antitumor immunity and reduced off-tumor immunity. In this review, we first discuss the cancer-immunity circle and how nanoparticles can modulate the key steps in this circle. Then, we highlight the recent advances in cancer immunotherapy with pH-responsive nanoparticles and discuss the perspective for this emerging area.

Cationic Nanostructures for Vaccines Design

Subunit vaccines rely on adjuvants carrying one or a few molecular antigens from the pathogen in order to guarantee an improved immune response. However, to be effective, the vaccine formulation usually consists of several components: an antigen carrier, the antigen, a stimulator of cellular immunity such as a Toll-like Receptors (TLRs) ligand, and a stimulator of humoral response such as an inflammasome activator. Most antigens are negatively charged and combine well with oppositely charged adjuvants. This explains the paramount importance of studying a variety of cationic supramolecular assemblies aiming at the optimal activity in vivo associated with adjuvant simplicity, positive charge, nanometric size, and colloidal stability. In this review, we discuss the use of several antigen/adjuvant cationic combinations. The discussion involves antigen assembled to 1) cationic lipids, 2) cationic polymers, 3) cationic lipid/polymer nanostructures, and 4) cationic polymer/biocompatible polymer nanostructures. Some of these cationic assemblies revealed good yet poorly explored perspectives as general adjuvants for vaccine design.

Nanomedicine and Onco-Immunotherapy: From the Bench to Bedside to Biomarkers

The broad relationship between the immune system and cancer is opening a new hallmark to explore for nanomedicine. Here, all the common and synergy points between both areas are reviewed and described, and the recent approaches which show the progress from the bench to the beside to biomarkers developed in nanomedicine and onco-immunotherapy.

Stimuli-Responsive Polymeric Nanocarriers for Drug Delivery, Imaging, and Theragnosis

In the past few decades, polymeric nanocarriers have been recognized as promising tools and have gained attention from researchers for their potential to efficiently deliver bioactive compounds, including drugs, proteins, genes, nucleic acids, etc., in pharmaceutical and biomedical applications. Remarkably, these polymeric nanocarriers could be further modified as stimuli-responsive systems based on the mechanism of triggered release, i.e., response to a specific stimulus, either endogenous (pH, enzymes, temperature, redox values, hypoxia, glucose levels) or exogenous (light, magnetism, ultrasound, electrical pulses) for the effective biodistribution and controlled release of drugs or genes at specific sites. Various nanoparticles (NPs) have been functionalized and used as templates for imaging systems in the form of metallic NPs, dendrimers, polymeric NPs, quantum dots, and liposomes. The use of polymeric nanocarriers for imaging and to deliver active compounds has attracted considerable interest in various cancer therapy fields. So-called smart nanopolymer systems are built to respond to certain stimuli such as temperature, pH, light intensity and wavelength, and electrical, magnetic and ultrasonic fields. Many imaging techniques have been explored including optical imaging, magnetic resonance imaging (MRI), nuclear imaging, ultrasound, photoacoustic imaging (PAI), single photon emission computed tomography (SPECT), and positron emission tomography (PET). This review reports on the most recent developments in imaging methods by analyzing examples of smart nanopolymers that can be imaged using one or more imaging techniques. Unique features, including nontoxicity, water solubility, biocompatibility, and the presence of multiple functional groups, designate polymeric nanocues as attractive nanomedicine candidates. In this context, we summarize various classes of multifunctional, polymeric, nano-sized formulations such as liposomes, micelles, nanogels, and dendrimers.

AIEgen-coupled upconversion nanoparticles eradicate solid tumors through dual-mode ROS activation

Reactive oxygen species (ROS) are essential for the regulation of antitumor immune responses, where they could induce immunogenic cell death, promote antigen presentation, and activate immune cells. Here, we report the development of near-infrared (NIR)-driven immunostimulants, based on coupling upconversion nanoparticles with aggregation-induced emission luminogens (AIEgens), to integrate the immunological effects of ROS for enhanced adaptive antitumor immune responses. Intratumorally injected AIEgen-upconversion nanoparticles produce high-dose ROS under high-power NIR irradiation, which induces immunogenic cell death and antigen release. These nanoparticles can also capture the released antigens and deliver them to lymph nodes. Upon subsequent low-power NIR treatment of lymph nodes, low-dose ROS are generated to further trigger efficient T cell immune responses through activation of dendritic cells, preventing both local tumor recurrence and distant tumor growth. The utility of dual-mode pumping power on AIEgen-coupled upconversion nanoparticles offers a powerful and controllable platform to activate adaptive immune systems for tumor immunotherapy.

Carbohydrate Conjugates in Vaccine Developments

Vaccines are powerful tools that can activate the immune system for protection against various diseases. As carbohydrates can play important roles in immune recognition, they have been widely applied in vaccine development. Carbohydrate antigens have been investigated in vaccines against various pathogenic microbes and cancer. Polysaccharides such as dextran and β-glucan can serve as smart vaccine carriers for efficient antigen delivery to immune cells. Some glycolipids, such as galactosylceramide and monophosphoryl lipid A, are strong immune stimulators, which have been studied as vaccine adjuvants. In this review, we focus on the current advances in applying carbohydrates as vaccine delivery carriers and adjuvants. We will discuss the examples that involve chemical modifications of the carbohydrates for effective antigen delivery, as well as covalent antigen-carbohydrate conjugates for enhanced immune responses.

Materials for Immunotherapy

Breakthroughs in materials engineering have accelerated the progress of immunotherapy in preclinical studies. The interplay of chemistry and materials has resulted in improved loading, targeting, and release of immunomodulatory agents. An overview of the materials that are used to enable or improve the success of immunotherapies in preclinical studies is presented, from immunosuppressive to proinflammatory strategies, with particular emphasis on technologies poised for clinical translation. The materials are organized based on their characteristic length scale, whereby the enabling feature of each technology is organized by the structure of that material. For example, the mechanisms by which i) nanoscale materials can improve targeting and infiltration of immunomodulatory payloads into tissues and cells, ii) microscale materials can facilitate cell-mediated transport and serve as artificial antigen-presenting cells, and iii) macroscale materials can form the basis of artificial microenvironments to promote cell infiltration and reprogramming are discussed. As a step toward establishing a set of design rules for future immunotherapies, materials that intrinsically activate or suppress the immune system are reviewed. Finally, a brief outlook on the trajectory of these systems and how they may be improved to address unsolved challenges in cancer, infectious diseases, and autoimmunity is presented.

Naringenin Enhances the Antitumor Effect of Therapeutic Vaccines by Promoting Antigen Cross-Presentation

Dendritic cells (DCs) can internalize and cross-present exogenous Ags to CD8⁺ T cells for pathogen or tumor cell elimination. Recently, growing evidences suggest the possible immunoregulatory role of flavonoids through modulating the Ag presentation of DCs. In this study, we report that naringenin, a grapefruit-derived flavonoid, possesses the ability to increase the Ag cross-presentation in both murine DC line DC2.4 as well as bone marrow-derived DCs, and naringenin-induced moderate intracellular oxidative stress that contributed to the disruption of lysosomal membrane enhanced Ag leakage to cytosol and cross-presentation. Moreover, in a murine colon adenocarcinoma model, naringenin induced more CD103⁺ DCs infiltration into tumor and facilitated the activation of CD8⁺ T cells and strengthened the performance of therapeutic E7 vaccine against TC-1 murine lung cancer. Our investigations may inspire novel thoughts for vaccine design and open a new field of potential applications of flavonoids as immunomodulators to improve host protection against infection and tumor.

Nanosystems for Improved Targeted Therapies in Melanoma

Melanoma is one of the most aggressive forms of skin cancer, with limited therapeutic options. Since its incidence has been rapidly rising in recent years, the study of new targeted therapeutic strategies has increased. The implication of nanoscience in the development of alternative targeted therapies for melanoma has multiple benefits and could significantly improve the outcome of melanoma patients. In this paper, we review the most recent progress in the field of targeted therapies, emphasizing the impact of nanoscale materials on the targeting and controlled release of anti-tumor drugs. The applications of nanomedicine in the management of melanoma are extensive and refer to sentinel lymph node mapping, chemotherapy, and RNA interference; each of these applications harboring the potential to develop efficient and personalized diagnostic techniques and therapies. Further research, especially in clinical trials, is needed to establish whether fighting melanoma on the nanoscale level represents the key to reaching a critical inflection point in mankind’s battle with metastatic melanoma.

Engineering ApoE3-incorporated biomimetic nanoparticle for efficient vaccine delivery to dendritic cells via macropinocytosis to enhance cancer immunotherapy

Efficient delivery of vaccines to dendritic cells (DCs) is critical for inducing sufficient immune response and realizing effective cancer immunotherapy. In the past decade, researchers have spent tremendous effort in delivering vaccines by using nanoparticles. However, most of the present strategies are designed based on receptor-mediated endocytosis to increase nanovaccines uptake by DCs, and underestimate the role of macropinocytosis in taking up exogenous antigen. Here, we proposed that macropinocytosis, an efficient pathway for DCs to internalize extracellular fluid-phase solutes, might be utilized as a highly-effective approach to facilitate nanovaccines uptake in DCs. Accordingly, we designed a biomimetic nanovaccine (R837-αOVA-ApoE3-HNP), composing of a poly-(D, l-lactide-co-glycolide) (PLGA) core to encapsulate adjuvant imiquimod (R837), a phospholipid membrane to load antigen peptide (αOVA), and apolipoprotein E3 (ApoE3), to boost the internalization of antigens into DCs. The nanovaccine exhibited highly efficient cellular uptake into DCs through the macropinocytosis pathway, and significantly promoted DCs maturation and antigen presentation. After subcutaneous injection, the nanovaccine was efficiently drained to lymph nodes. Strong T cell immune responses including the generation of antigen-specific CD8⁺ T cells, expansion of IFN-γ⁺ CD8⁺ T cells and the secretion of IFN-γ⁺ were observed after the vaccination of R837-αOVA-ApoE3-HNP. It also efficiently inhibited the formation of tumor metastasis in lung as a prevention vaccine, and exerted superior therapeutic efficiency on B16-OVA tumor-bearing mice when in combination with αPD-1 therapy. Overall, our work demonstrated that by utilizing the macropinocytosis pathway, ApoE3-incorporated biomimetic nanoparticle has great potential to function as a feasible, effective, and safe nanovaccine for cancer immunotherapy.

Tumor Cell-associated Exosomes Robustly Elicit Anti-tumor Immune Responses through Modulating Dendritic Cell Vaccines in Lung Tumor

DC vaccine-based immunotherapy is emerging as a novel therapeutic strategy for cancer treatment, however, antitumor effect of DC vaccines based on tumor cell lysates (TCLs) remains unsatisfactory due to poor immunogenicity of tumor antigens. Although tumor-associated exosomes (TAEs) have been reported as a promising antigen for DC vaccines, it remains unclear how TAE-based DC vaccine induced antitumor immunity in lung cancer.

Methods: In the present study, we extracted TAEs from the supernatant of tumor cell culture medium, and compared the effect of TAEs with TCLs on DCs. To further evaluate the therapeutic effect of DC_TAE, we used immunofluorescence and flow cytometry to evaluate the apoptosis of tumor tissue, tumor-infiltrating CD8⁺ T cells and Tregs in TDLNs and spleen. Then the levels of cytokines of IL-12, IFN-γ, L-10 and TGF-β were quantified by ELISA assays.

Results: Our data showed that TAEs were more potent than TCLs to promote DC maturation and enhance MHC cross presentation, which directly contributed to more robust tumor-specific cytotoxic T lymphocyte (CTL) response. More importantly, TAEs reduced the expression of PD-L1 of DCs, thereby led to down-regulated population of Tregs in vitro. Moreover, DC_TAE remarkably suppressed the tumor growth and prolonged survival rate in vivo, due to participance of CD8⁺ T cells and decreased Tregs in TDLNs and spleen.

Conclusion: TAEs could serve to improve vaccine-elicited immunotherapy by triggering stronger DC-mediated immune responses and decreasing Tregs in the tumor microenvironment.

Tumor immune microenvironment modulation-based drug delivery strategies for cancer immunotherapy

The past years have witnessed promising clinical feedback for anti-cancer immunotherapies, which have become one of the hot research topics; however, they are limited by poor delivery kinetics, narrow patient response profiles, and systemic side effects. To the best of our knowledge, the development of cancer is highly associated with the immune system, especially the tumor immune microenvironment (TIME). Based on the comprehensive understanding of the complexity and diversity of TIME, drug delivery strategies focused on the modulation of TIME can be of great significance for directing and improving cancer immunotherapy. This review highlights the TIME modulation in cancer immunotherapy and summarizes the versatile TIME modulation-based cancer immunotherapeutic strategies, medicative principles and accessory biotechniques for further clinical transformation. Remarkably, the recent advances of cancer immunotherapeutic drug delivery systems and future prospects of TIME modulation-based drug delivery systems for much more controlled and precise cancer immunotherapy will be emphatically discussed.

Synergistic effect of all-trans-retinal and triptolide encapsulated in an inflammation-targeted nanoparticle on collagen-induced arthritis in mice

Targeted delivery of nano-encapsulated anti-inflammatory agent represents a promising while challenging strategy in the treatment of rheumatoid arthritis (RA). Pro-inflammatory macrophages play a major role in the pathogenesis of RA. In this study, we investigated the effect of a macrophage-targeted pH-sensitive nanoparticle on collagen-induced arthritis (CIA) in mice. To target macrophage, all-trans-retinal was conjugated into dextran backbone through pH-sensitive hydrazone bond, then grafted with galactose (GDR). This nanoparticle was used for the encapsulation of triptolide (TPT), a potent anti-inflammatory compound isolated from Chinese herb. As expected, GDR nanoparticles preferentially accumulated in the inflammatory tissues. Treatment with GDR-TPT nanoparticles resulted in a marked decrease in the infiltration of CD3⁺ T cells and F4/80⁺ macrophages and reduction of the expression of TNF-α, IL-6 and IL-1β in the inflamed lesions of CIA mice. Furthermore, Th1 and Th17 responses were also inhibited. Importantly, anti-arthritic effect of TPT was markedly enhanced while its toxic effect was attenuated by encapsulating with GDR. GDR by itself also had moderate effect in the inhibition of arthritis, due to its intrinsic anti-inflammatory property. Therefore, our results clearly show that GDR-TPT nanoparticle may represent a promising drug delivery system for the treatment of RA.

Antigen-Inorganic Hybrid Flowers-Based Vaccines with Enhanced Room Temperature Stability and Effective Anticancer Immunity

Particle-based antigen carriers as adjuvants play an important role in vaccine development. Herein, an antigen-inorganic hybrid flower-like particle is developed as a novel vaccine carrier. Model antigen ovalbumin (OVA)-copper (II) sulfate hybrid vaccines (OVA-Cu-HVs) are mildly and facilely constructed through a biomimetic mineralization process. OVA-Cu-HVs facilitate cellular uptake in antigen-presenting cells and the internalization of OVA-Cu-HVs involves macropinocytosis-mediated endocytosis. OVA-Cu-HVs can release OVA in a pH-responsive behavior and promote cytosolic release of antigen to enhance antigen cross-presentation. Immunization with OVA-Cu-HVs promotes the maturation of dendritic cells in draining lymph nodes, induces robust antigen-specific T lymphocyte response, and inhibits tumor growth in vivo. In addition, OVA-Cu-HVs are efficacious after being stored for 4 weeks at room temperature and are expected to simplify vaccine storage and lower the cost of cold storage for transportation. Looking forward, OVA-Cu-HVs may hold strong potential to be as an effective vaccine delivery platform, which will facilitate the application of organic-inorganic hybrid flowers in biomedical areas.

Nanoparticle Delivery of Immunostimulatory Agents for Cancer Immunotherapy

Immunostimulatory agents, including adjuvants, cytokines, and monoclonal antibodies, hold great potential for the treatment of cancer. However, their direct administration often results in suboptimal pharmacokinetics, vulnerability to biodegradation, and compromised targeting. More recently, encapsulation into biocompatible nanoparticulate carriers has become an emerging strategy for improving the delivery of these immunotherapeutic agents. Such approaches can address many of the challenges facing current treatment modalities by endowing additional protection and significantly elevating the bioavailability of the encapsulated payloads. To further improve the delivery efficiency and subsequent immune responses associated with current nanoscale approaches, biomimetic modifications and materials have been employed to create delivery platforms with enhanced functionalities. By leveraging nature-inspired design principles, these biomimetic nanodelivery vehicles have the potential to alter the current clinical landscape of cancer immunotherapy.

Advances of functional nanomaterials for cancer immunotherapeutic applications

Immunotherapy has made great progress by modulating the body's own immune system to fight against cancer cells. However, the low response rates of related drugs limit the development of immunotherapy strategies. Fortunately, the advantages of nanotechnology can just make up for this shortcoming. Nanocarriers of diverse systems are utilized to co-deliver antigens and adjuvants, combined with drugs for immunomodulatory, such as chemotherapy, radiotherapy, and photodynamic. Here we review recent studies on immunotherapy with biomimetic, organic, and inorganic nanomaterials. They are going to potentially overcome the drawbacks in cancer immunotherapy with delivering immunomodulatory drugs, delivering cancer vaccine, and monitoring the immune systems. This article is characterized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

An overview of nanogel-based vaccines

Introduction: The development of more efficacious vaccines, especially subunit vaccines administered via non-invasive routes, is a priority in vaccinology. Nanogels are materials that can meet the requirements to serve as efficient vaccine delivery vehicles (in terms of thermo-sensitivity, biocompatibility, and pH-responsiveness; among others); thus there is a growing interest in exploring the potential of nanogels for vaccine development. Areas covered: Herein, a critical analysis of nanogel synthesis methodologies is presented and nanogel-based vaccines under development are summarized and placed in perspective. Promising vaccine candidates based on nanogels have been reported for cancer, obesity, and infectious diseases (mainly respiratory diseases). Some of the candidates were administered by mucosal routes which are highly attractive in terms of simple administration and induction of protective responses at both mucosal and systemic levels. Expert opinion: The most advanced models of nanogel-based vaccines comprise candidates against cancer, based on cholesteryl pullulan nanogels evaluated in clinical trials with promising findings; as well as some vaccines against respiratory pathogens tested in mice thus far. Nonetheless, the challenge for this field is advancing in clinical trials and proving the protective potential in test animals for many other candidates. Implementing green synthesis approaches for nanogels is also required.

At the bench: Engineering the next generation of cancer vaccines

Cancer vaccines hold promise as an immunotherapeutic modality based on their potential to generate tumor antigen-specific T cell responses and long-lived antitumor responses capable of combating metastatic disease and recurrence. However, cancer vaccines have historically failed to deliver significant therapeutic benefit in the clinic, which we maintain is due in part to drug delivery challenges that have limited vaccine immunogenicity and efficacy. In this review, we examine some of the known and putative failure mechanisms of common first-generation clinical cancer vaccines, and describe how the rational design of materials engineered for vaccine delivery and immunomodulation can address these shortcomings. First, we outline vaccine design principles for augmenting cellular immunity to tumor antigens and describe how well-engineered materials can improve vaccine efficacy, highlighting recent innovations in vaccine delivery technology that are primed for integration into neoantigen vaccine development pipelines. We also discuss the importance of sequencing, timing, and kinetics in mounting effective immune responses to cancer vaccines, and highlight examples of materials that potentiate antitumor immunity through spatiotemporal control of immunomodulation. Furthermore, we describe several engineering strategies for improving outcomes of in situ cancer vaccines, which leverage local, intratumoral delivery to stimulate systemic immunity. Finally, we highlight recent innovations leveraging nanotechnology for increasing the immunogenicity of the tumor microenvironment (TME), which is critical to enhancing tumor infiltration and function of T cells elicited in response to cancer vaccines. These immunoengineering strategies and tools complement ongoing advances in cancer vaccines as they reemerge as an important component of the immunotherapeutic armamentarium.

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

Most cancer vaccines are unsuccessful in eliciting clinically relevant effects. Without using exogenous antigens and adoptive cells, we show a concept of utilizing biologically reprogrammed cytomembranes of the fused cells (FCs) derived from dendritic cells (DCs) and cancer cells as tumor vaccines. The fusion of immunologically interrelated two types of cells results in strong expression of the whole tumor antigen complexes and the immunological co-stimulatory molecules on cytomembranes (FMs), allowing the nanoparticle-supported FM (NP@FM) to function like antigen presenting cells (APCs) for T cell immunoactivation. Moreover, tumor-antigen bearing NP@FM can be bio-recognized by DCs to induce DC-mediated T cell immunoactivation. The combination of these two immunoactivation pathways offers powerful antitumor immunoresponse. Through mimicking both APCs and cancer cells, this cytomembrane vaccine strategy can develop various vaccines toward multiple tumor types and provide chances for accommodating diverse functions originating from the supporters.

Cold Atmospheric Plasma as an Adjunct to Immunotherapy for Glioblastoma Multiforme

Glioblastoma multiforme (GBM) is the most common and aggressive form of brain cancer in adults. GBM carries a dismal prognosis because of its proliferative, invasive, and angiogenic capabilities and because of its ability to downregulate the immune system. Immune-based therapies under investigation for GBM have been unsuccessful in vivo because of this downregulation. Cold atmospheric plasma (CAP) is a high-energy state of matter that can be applied directly or indirectly to tumor tissue to serve as an adjunct to immunotherapy in the treatment of GBM because it upregulates the immune system by the induction of reactive oxygen species. CAP has the potential to improve the efficacy of existing and investigative immunotherapies for GBM.

Biohybrid Vaccines for Improved Treatment of Aggressive Melanoma with Checkpoint Inhibitor

Recent approaches in the treatment of cancer focus on involving the immune system to control the tumor growth. The administration of immunotherapies, like checkpoint inhibitors, has shown impressive results in the long term survival of patients. Cancer vaccines are being investigated as further tools to prime tumor-specific immunity. Biomaterials show potential as adjuvants in the formulation of vaccines, and biomimetic elements derived from the membrane of tumor cells may widen the range of antigens contained in the vaccine. Here, we show how mice presenting an aggressive melanoma tumor model treated twice with the complete nanovaccine formulation showed control on the tumor progression, while in a less aggressive model, the animals showed remission and control on the tumor progression, with a modification in the immunological profile of the tumor microenvironment. We also prove that co-administration of the nanovaccine together with a checkpoint inhibitor increases the efficacy of the treatment (87.5% of the animals responding, with 2 remissions) compared to the checkpoint inhibitor alone in the B16.OVA model. Our platform thereby shows potential applications as a cancer nanovaccine in combination with the standard clinical care treatment for melanoma cancers.

Tailored Polymers with Complement Activation Ability To Improve Antitumor Immunity

The complement system plays an important role in host innate immunity, and its activation can be exploited as a potential strategy for vaccine adjuvants. Herein, a pH-responsive micellar vaccine platform (COOH-NPs) was developed using a carboxyl-modified diblock copolymer of poly(2-ethyl-2-oxazoline)-poly(d,l-lactide) (COOH-PEOz-PLA). The copolymer self-assembled into micelles with hydroxyl groups shielding on the surface, which activated the complement system for the enhanced immune responses. Compared with the control nanoparticles (OCH₃-NPs), COOH-NPs significantly enhanced lymph node-resident dendritic cell maturation, antigen-specific IgG production, antigen-specific CD4⁺ and CD8⁺ T-cell activation, and the amount of memory T-cell generation in vivo. Furthermore, immunization with COOH-NPs/OVA in E.G7-OVA tumor-bearing mice not only remarkably inhibited tumor growth but also prolonged the survival of tumor-bearing mice. These results indicated that COOH-NPs with the capability of complement activation efficiently boosted the immune responses for the antitumor effect. The study demonstrated the significance of taking advantage of a complement-activating vaccine platform for cancer immunotherapy.

Tomato lectin-modified nanoemulsion-encapsulated MAGE1-HSP70/SEA complex protein vaccine: Targeting intestinal M cells following peroral administration

Vaccines administered orally enable the stimulation of both the mucous membrane and system immune responses. However, tumor vaccines, whose effective elements are antigen protein molecules or gene-encoding antigens, are hardly accustomed to the harsh gastrointestinal environment. Here, we explored an oral nanoecapsulated tumor vaccine complex to evaluate the anti-tumor effect. Tomato lectin (TL) was modified on the surface of a nanoemulsion (NE) composed of MAGE1-HSP70/SEA (MHS). C57BL/6 mice were immunized with NE (-), NE (MHS) and TL-NE (MHS) via po. or sc. administration. Additionally, the cellular immunocompetence was detected by the enzyme-linked immunospot assay and lactate dehydrogenase release assay. Serum antibody titers were analyzed using the enzyme-linked immuno sorbent assay. Next, the therapeutic and tumor challenge assays were performed. The TL-NE (MHS) particles were 20 ± 5 nm in diameter and could resist pepsin and trypsin digestion. The cellular immune responses elicited by TL-NE (MHS) perioral were stronger than those by TL-NE (MHS)-sc. (p < 0.05) when targeted to B16-MAGE1 tumor cells. The levels of MAGE-1 antibody induced by TL-NE (MHS) via the oral route was higher than control group (p < 0.05). The percentage of CD4+ and CD8+ T cells in TL-NE (MHS)-po. group was more than other groups (p < 0.05). Furthermore, oral TL-NE (M)HScould delay tumor growth and defer tumor occurrence and tumor recurrence after resection in mice challenged with B16-MAGE-1 tumor cells. The study suggested that the oral TL-NE (MHS) vaccine delivery system is feasible to improve the vaccine protection effect and may have broad application in cancer therapy.

Emerging Nano-/Microapproaches for Cancer Immunotherapy

Cancer immunotherapy has achieved remarkable clinical efficacy through recent advances such as chimeric antigen receptor-T cell (CAR-T) therapy, immune checkpoint blockade (ICB) therapy, and neoantigen vaccines. However, application of immunotherapy in a clinical setting has been limited by low durable response rates and immune-related adverse events. The rapid development of nano-/microtechnologies in the past decade provides potential strategies to improve cancer immunotherapy. Advances of nano-/microparticles such as virus-like size, high surface to volume ratio, and modifiable surfaces for precise targeting of specific cell types can be exploited in the design of cancer vaccines and delivery of immunomodulators. Here, the emerging nano-/microapproaches in the field of cancer vaccines, immune checkpoint blockade, and adoptive or indirect immunotherapies are summarized. How nano-/microparticles improve the efficacy of these therapies, relevant immunological mechanisms, and how nano-/microparticle methods are able to accelerate the clinical translation of cancer immunotherapy are explored.

Biomimetic Nanoparticle Vaccines for Cancer Therapy

It is currently understood that, in order for a tumor to successfully grow, it must evolve means of evading immune surveillance. In the past several decades, researchers have leveraged increases in our knowledge of tumor immunology to develop therapies capable of augmenting endogenous immunity and eliciting strong antitumor responses. In particular, the goal of anticancer vaccination is to train the immune system to properly utilize its own resources in the fight against cancer. Although attractive in principle, there are currently only limited examples of anticancer vaccines that have been successfully translated to the clinic. Recently, there has been a significant push towards the use of nanotechnology for designing vaccine candidates that exhibit enhanced potency and specificity. In this progress report, we discuss recent developments in the field of anticancer nanovaccines. By taking advantage of the flexibility offered by nanomedicine to purposefully program immune responses, this new generation of vaccines has the potential to address many of the hurdles facing traditional platforms. A specific emphasis is placed on the emergence of cell membrane-coated nanoparticles, a novel biomimetic platform that can be used to generate personalized nanovaccines that elicit strong, multi-antigenic antitumor responses.

Recent development in biodegradable nanovehicle delivery system-assisted immunotherapy

A schematic illustration of BNDS biodegradation and release antigen delivery for assisting immunotherapy.

Nanoparticle-Mediated Remodeling of the Tumor Microenvironment to Enhance Immunotherapy

Nanoscience has long been lauded as a method through which tumor-associated barriers could be overcome. As successful as cancer immunotherapy has been, limitations associated with the tumor microenvironment or side effects of systemic treatment have become more apparent. In this Review, we seek to lay out the therapeutic challenges associated with the tumor microenvironment and the ways in which nanoscience is being applied to remodel the tumor microenvironment and increase the susceptibility of many cancer types to immunotherapy. We detail the nanomedicines on the cutting edge of cancer immunotherapy and how their interactions with the tumor microenvironment make them more effective than systemically administered immunotherapies.

Nanoparticle drug delivery systems: an excellent carrier for tumor peptide vaccines

In the past 40 years, the nanoparticle drug delivery system for tumor peptide vaccines has been widely studied which also reached a splendid result. Nanomaterial can enhance the targeting of vaccines, help vaccines enter the cells and trigger immune response by themselves. They also help in increasing cellular uptake, improving permeability and efficacy. Currently, several categories of nanopreparation, such as liposome, polymeric micelle, polymeric nanoparticle, gold nanoparticle and so on, are proved that they are appropriate for peptide vaccines. This review we discussed the possible mechanisms of nanomaterial's action on the regulation of immunological functions and several major applications of this advanced drug delivery system for tumor peptide vaccine.

Nanovaccine Incorporated with Hydroxychloroquine Enhances Antigen Cross-Presentation and Promotes Antitumor Immune Responses

Induction of effective antigen-specific CD8⁺ T-cell responses is critical for cancer immunotherapy success. Hydroxychloroquine (HCQ) is a widely used classical antimalarial and antirheumatic drug. HCQ is also an endosomal membrane disrupting agent that can lead to vesicular swelling and membrane permeabilization, which likely facilitates the release of therapeutic agents from lysosomes into the cytoplasm. Here, we develop a minimalistic nanovaccine, which is composed of poly(lactide- co-glycolide)acid (PLGA) nanoparticles (NPs) encapsulating a physical mixture of ovalbumin (OVA, a model antigen) and HCQ (HCQ-OVA-PLGA NPs). We tested whether HCQ could spatiotemporally control the cytosolic delivery of antigens, enhance antigen processing and presentation via the major histocompatibility complex (MHC)-I pathway, and thus generate a sufficient antitumor cytotoxic T-cell response. The results of in vitro experiments showed that HCQ-OVA-PLGA NPs significantly enhanced OVA escape from lysosomes into the cytoplasm within bone-marrow-derived dendritic cells. We also observed that HCQ-OVA-PLGA NPs enhanced the expression level of MHC-I on dendritic cells and improved cross-presentation of antigen, compared to free OVA or OVA-PLGA NPs. Results of in vivo experiments confirmed that HCQ initiated Th1-type responses and strong CD8⁺ T-cell responses that induced tumor cell apoptosis. Moreover, vaccination of mice with HCQ-OVA-PLGA NPs effectively generated memory immune responses in vivo and prevented tumor progression. We conclude that co-encapsulation of HCQ with antigens in nanovaccines can boost antigen-specific antitumor immune responses, particularly through CD8⁺ T-cells, serving as a simple and effective platform for the treatment of tumors and infectious diseases.

Glutathione-depletion mesoporous organosilica nanoparticles as a self-adjuvant and Co-delivery platform for enhanced cancer immunotherapy

Silica based nanoparticles have emerged as a promising vaccine delivery system for cancer immunotherapy, but their bio-degradability, adjuvanticity and the resultant antitumor activity remain to be largely improved. In this study, we report biodegradable glutathione-depletion dendritic mesoporous organosilica nanoparticles (GDMON) with a tetrasulfide-incorporated framework as a novel co-delivery platform in cancer immunotherapy. Functionalized GDMON are capable of co-delivering an antigen protein (ovalbumin) and a toll-like receptor 9 (TLR9) agonist into antigen presenting cells (APCs) and inducing endosome escape. Moreover, decreasing the intracellular glutathione (GSH) level through the -S-S-/GSH redox chemistry increases the ROS generation level both in vitro and in vivo, facilitating cytotoxic T lymphocyte (CTL) proliferation and reducing tumour growth in an aggressive B16-OVA melanoma tumour model. Our results have shown the potential of GDMON as a novel self-adjuvant and co-delivery nanocarrier for cancer vaccine.

Photothermally Controlled MHC Class I Restricted CD8+ T-Cell Responses Elicited by Hyaluronic Acid Decorated Gold Nanoparticles as a Vaccine for Cancer Immunotherapy

Cancer vaccines aim to induce a strong major histocompatibility complex class I (MHC-I)-restricted CD8⁺ cytotoxic T-cell response, which is an important prerequisite for successful cancer immunotherapy. Herein, a hyaluronic acid (HA) and antigen (ovalbumin, OVA)-decorated gold nanoparticle (AuNPs)-based (HA-OVA-AuNPs) vaccine is developed for photothermally controlled cytosolic antigen delivery using near-infrared (NIR) irradiation and is found to induce antigen-specific CD8⁺ T-cell responses. Chemical binding of thiolated HA and OVA to AuNPs facilitates antigen uptake of dendritic cells via receptor-mediated endocytosis. HA-OVA-AuNPs exhibit enhanced NIR absorption and thermal energy translation. Cytosolic antigen delivery is then permitted through the photothermally controlled process of local heat-mediated endo/lysosome disruption by laser irradiation along with reactive oxygen species generation, which helps to augment proteasome activity and downstream MHC I antigen presentation. Consequently, the HA-OVA-AuNPs nanovaccine can effectively evoke a potent anticancer immune response in mice under laser irradiation. This NIR-responsive nanovaccine is promising as a potent vaccination method for improving cancer vaccine efficacy.

Unintended effects of drug carriers: Big issues of small particles

Humoral and cellular host defense mechanisms including diverse phagocytes, leukocytes, and immune cells have evolved over millions of years to protect the body from microbes and other external and internal threats. These policing forces recognize engineered sub-micron drug delivery systems (DDS) as such a threat, and react accordingly. This leads to impediment of the therapeutic action, extensively studied and discussed in the literature. Here, we focus on side effects of DDS interactions with host defenses. We argue that for nanomedicine to reach its clinical potential, the field must redouble its efforts in understanding the interaction between drug delivery systems and the host defenses, so that we can engineer safer interventions with the greatest potential for clinical success.

ROS-Inducing Micelles Sensitize Tumor-Associated Macrophages to TLR3 Stimulation for Potent Immunotherapy

One approach to cancer immunotherapy is the repolarization of immunosuppressive tumor-associated macrophages (TAMs) to antitumor M1 macrophages. The present study developed galactose-functionalized zinc protoporphyrin IX (ZnPP) grafted poly(l-lysine)- b-poly(ethylene glycol) polypeptide micelles (ZnPP PM) for TAM-targeted immunopotentiator delivery, which aimed at in vivo repolarization of TAMs to antitumor M1 macrophages. The outcomes revealed that ROS-inducing ZnPP PM demonstrated specificity for the in vitro and in vivo targeting of macrophages, elevated the level of ROS, and lowered STAT3 expression in BM-TAMs. Poly I:C (PIC, a TLR3 agonist)-loaded ZnPP PM (ZnPP PM/PIC) efficiently repolarized TAMs to M1 macrophages, which were reliant on ROS generation. Further, ZnPP PM/PIC substantially elevated the activated NK cells and T lymphocytes in B16-F10 melanoma tumors, which caused vigorous tumor regression. Therefore, the TAM-targeted transport of an immunologic adjuvant with ZnPP-grafted nanovectors may be a potential strategy to repolarize TAMs to M1 macrophages in situ for effective cancer immunotherapy.

Targeting Accessories to the Crime: Nanoparticle Nucleic Acid Delivery to the Tumor Microenvironment

Nucleic acid delivery for cancer holds extraordinary promise. Increasing expression of tumor suppressor genes or inhibition of oncogenes in cancer cells has important therapeutic potential. However, several barriers impair progress in cancer gene delivery. These include effective delivery to cancer cells and relevant intracellular compartments. Although viral gene delivery can be effective, it has the disadvantages of being immuno-stimulatory, potentially mutagenic and lacking temporal control. Various nanoparticle (NP) platforms have been developed to overcome nucleic acid delivery hurdles, but several challenges still exist. One such challenge has been the accumulation of NPs in non-cancer cells within the tumor microenvironment (TME) as well as the circulation. While uptake by these cancer-associated cells is considered to be an off-target effect in some contexts, several strategies have now emerged to utilize NP-mediated gene delivery to intentionally alter the TME. For example, the similarity of NPs in shape and size to pathogens promotes uptake by antigen presenting cells, which can be used to increase immune stimulation and promote tumor killing by T-lymphocytes. In the era of immunotherapy, boosting the ability of the immune system to eliminate cancer cells has proven to be an exciting new area in cancer nanotechnology. Given the importance of cancer-associated cells in tumor growth and metastasis, targeting these cells in the TME opens up new therapeutic applications for NPs. This review will cover evidence for non-cancer cell accumulation of NPs in animal models and patients, summarize characteristics that promote NP delivery to different cell types, and describe several therapeutic strategies for gene modification within the TME.

Redox control of cancer cell destruction

Redox regulation has been proposed to control various aspects of carcinogenesis, cancer cell growth, metabolism, migration, invasion, metastasis and cancer vascularization. As cancer has many faces, the role of redox control in different cancers and in the numerous cancer-related processes often point in different directions. In this review, we focus on the redox control mechanisms of tumor cell destruction. The review covers the tumor-intrinsic role of oxidants derived from the reduction of oxygen and nitrogen in the control of tumor cell proliferation as well as the roles of oxidants and antioxidant systems in cancer cell death caused by traditional anticancer weapons (chemotherapeutic agents, radiotherapy, photodynamic therapy). Emphasis is also put on the role of oxidants and redox status in the outcome following interactions between cancer cells, cytotoxic lymphocytes and tumor infiltrating macrophages.

Endocytosed soluble cowpox virus protein CPXV012 inhibits antigen cross-presentation in human monocyte-derived dendritic cells

Viruses may interfere with the MHC class I antigen presentation pathway in order to avoid CD8⁺ T cell-mediated immunity. A key target within this pathway is the peptide transporter TAP. This transporter plays a central role in MHC class I-mediated peptide presentation of endogenous antigens. In addition, TAP plays a role in antigen cross-presentation of exogenously derived antigens by dendritic cells (DCs). In this study, a soluble form of the cowpox virus TAP inhibitor CPXV012 is synthesized for exogenous delivery into the antigen cross-presentation route of human monocyte-derived (mo)DCs. We show that soluble CPXV012 localizes to TAP⁺ compartments that carry internalized antigen and is a potent inhibitor of antigen cross-presentation. CPXV012 stimulates the prolonged deposition of antigen fragments in storage compartments of moDCs, as a result of reduced endosomal acidification and reduced antigen proteolysis when soluble CPXV012 is present. Thus, a dual function can be proposed for CPXV012: inhibition of TAP-mediated peptide transport and inhibition of endosomal antigen degradation. We propose this second function for soluble CPXV012 can serve to interfere with antigen cross-presentation in a peptide transport-independent manner.

Synthetic Polymeric Mixed Micelles Targeting Lymph Nodes Trigger Enhanced Cellular and Humoral Immune Responses

It has been widely accepted that lymph nodes (LNs) are critical targets of cancer vaccines because antigen presentation and initiation of T-cell-mediated immune responses occur primarily at these locations. In this study, amphiphilic diblock copolymer poly(2-ethyl-2-oxazoline)-poly(d,l-lactide) (PEOz-PLA) combined with carboxylterminated-Pluronic F127 was used to construct mixed micelles [carboxylated-nanoparticles (NPs)] for codelivery of antigen ovalbumin (OVA) and Toll-like receptor-7 agonist CL264 (carboxylated-NPs/OVA/CL264) to the LN-resident dendritic cells (DCs). The results showed that the small, sub-60 nm size of the self-assembled mixed micelles enables them to rapidly penetrate into lymphatic vessels and reach draining lymph nodes after subcutaneous injection. Furthermore, the surface modification with carboxylic groups imparted the carboxylated-NPs with endocytic receptor-targeting ability, allowing for DC internalization of carboxylated-NPs/OVA/CL264 via the scavenger receptor-mediated pathway. Because stimulation of CL264 in early endosomes will lead to a more effective immune response than that in late endo/lysosomes, the mass ratio of PEOz-PLA to carboxylated-Pluronic F127 in the mixed micelles was adjusted to release the encapsulated CL264 to the early endosome, resulting in increased expression of costimulatory molecules and secretion of stimulated cytokines by DCs. Moreover, the incorporation of PEOz outside the micellar shell effectively augmented MHC I antigen presentation through facilitating endosome escape and cytosolic release of antigens. This in turn evoked potent immune responses in vivo, including activation of antigen-specific T-cell responses, production of antigen-specific IgG antibodies, and generation of cytotoxic T-lymphocyte responses. Finally, immunization with the codelivery system in E.G7-OVA tumor-bearing mice could not only significantly inhibit tumor growth but also markedly prolong the survival of tumor-bearing mice. Taken together, carboxylated-NPs/OVA/CL264 have demonstrated great potential for clinical applications as an effective antitumor vaccine for further immunotherapy.

Simple and Green Strategy for the Synthesis of "Pathogen-Mimetic" Glycoadjuvant@AuNPs by Combination of Photoinduced RAFT and Bioinspired Dopamine Chemistry

Innate immune responses recognizing pathogen associated molecular patterns (PAMPs) play a crucial role in adaptive immunity. Toll-like receptors (TLRs) and C-type lectin receptors (CLRs) contribute to antigen capture, uptake, presentation and activation of immune responses. In this contribution, metal-free reversible addition-fragmentation chain transfer (RAFT) polymerization of N-3,4-dihydroxybenzenethyl methacrylamide (DMA) and 2-(methacrylamido) glucopyranose (MAG) under sunlight irradiation using 2-cyanoprop-2-yl-α-dithionaphthalate (CPDN) as iniferter agent, can be employed to fabricate the multivalent glycopolymer containing bioresponsive sugar group and multifunctional catechol functionalities. The polymerization behavior is investigated and it presents controlled features. Moreover, bioinspired dopamine chemistry can be successfully utilized to form in situ glycopolymer-coated gold nanoparticles (AuNPs) without the need of additional reducing reagent, design "pathogen-mimetic" glycoadjuvant recognized by both CLRs and TLRs. The synthetic glycoadjuvant is found to enhance the adjuvant activity as "infected signals" in vitro.

Single dose HBsAg CS-γ-PGA nanogels induce potent protective immune responses against HBV infection

Hepatitis B virus (HBV) infection is a severe threat to public health, which can be prevented by prophylactic vaccination. Here, we tested nanogels carriers in the prophylactic effect of hepatitis B surface antigen (HBsAg) vaccine. HBsAg nanogels (Ng) were prepared using chitosan (CS) and poly-γ-glutamic acid (γ-PGA). Positively charged Ng (+) and negatively charged Ng (-) were prepared by adjusting the CS and γ-PGA proportion. Dendritic cells (DCs) maturation in mice immunized with HBsAg Ng (+) and HBsAg Ng (-) could be augmented in response to pAAV/HBV1.2 plasmid challenge. Single-dose immunization with HBsAg Ng (+) induced HBsAg specific-antibodies. HBsAg Ng (+) immunized mice cleared HBsAg and restored anti-HBs production after pAAV/HBV1.2 plasmid challenge. Single-dose HBsAg Ng (+) induced humoral and cellular immunity, and could induce effector memory T cells. Single-dose HBsAg Ng (-) favored the induction of cellular immunity, and induced central memory T cells and effector memory T cells. However, HBsAg elimination was similar between HBsAg Ng (+)- and HBsAg Ng (+) plus HBsAg Ng (-)-immunized mice. Zeta potential measurements showed that HBsAg Ng (+) were more stable than HBsAg Ng (-). Therefore, Ng (+) are desirable HBsAg prophylactic vaccine carriers, providing long-term protection against HBV, and are a good choice to study and apply weakly immunostimulatory antigens.

Nanoparticles: augmenting tumor antigen presentation for vaccine and immunotherapy treatments of cancer

The major goal of immunity is maintaining host survival. Toward this, immune cells recognize and eliminate targets that pose a danger. Primarily, these are external invaders (pathogens) and internal invaders (cancers). Their recognition relies on distinguishing foreign components (antigens) from self-antigens. Since cancer cells are the host's own cells that are harmfully altered, they are difficult to distinguish from normal self. Furthermore, the antigens least resembling the host are often sequestered in parts of the tumor least accessible to immune responses. Therefore, to sufficiently boost immunity, these tumor antigens must be exposed to the immune system. Toward this, nanoparticles provide an innovating means of tumor antigen presentation and are destined to become an integral part of cancer immunotherapy.

Basic concepts and recent advances in nanogels as carriers for medical applications

Nanogels in biomedical field are promising and innovative materials as dispersions of hydrogel nanoparticles based on crosslinked polymeric networks that have been called as next generation drug delivery systems due to their relatively high drug encapsulation capacity, uniformity, tunable size, ease of preparation, minimal toxicity, stability in the presence of serum, and stimuli responsiveness. Nanogels show a great potential in chemotherapy, diagnosis, organ targeting and delivery of bioactive substances. The main subjects reviewed in this article concentrates on: (i) Nanogel assimilation in the nanomedicine domain; (ii) Features and advantages of nanogels, the main characteristics, such as: swelling capacity, stimuli sensitivity, the great surface area, functionalization, bioconjugation and encapsulation of bioactive substances, which are taken into account in designing the structures according to the application; some data on the advantages and limitations of the preparation techniques; (iii) Recent progress in nanogels as a carrier of genetic material, protein and vaccine. The majority of the scientific literature presents the multivalency potential of bioconjugated nanogels in various conditions. Today's research focuses over the overcoming of the restrictions imposed by cost, some medical requirements and technological issues, for nanogels' commercial scale production and their integration as a new platform in biomedicine.