Immunomodulatory Nanosystems

Biocompatibility of nanomaterials and their immunological properties

Nanomaterials (NMs) have revolutionized multiple aspects of medicine by enabling novel sensing, diagnostic, and therapeutic approaches. Advancements in processing and fabrication have also allowed significant expansion in the applications of the major classes of NMs based on polymer, metal/metal oxide, carbon, liposome, or multi-scale macro-nano bulk materials. Concomitantly, concerns regarding the nanotoxicity and overall biocompatibility of NMs have been raised. These involve putative negative effects on both patients and those subjected to occupational exposure during manufacturing. In this review, we describe the current state of testing of NMs including those that are in clinical use, in clinical trials, or under development. We also discuss the cellular and molecular interactions that dictate their toxicity and biocompatibility. Specifically, we focus on the reciprocal interactions between NMs and host proteins, lipids, and sugars and how these induce responses in immune and other cell types leading to topical and/or systemic effects.

Dissolving microneedles delivering cancer cell membrane coated nanoparticles for cancer immunotherapy

Recently, a variety of tumor vaccines and immune system stimulators such as toll-like receptor (TLR) agonists have been widely investigated for cancer immunotherapy via transdermal delivery. Despite these great research efforts, low efficiency and discomfort remain a huge technical hurdle for the development of immunotherapeutics. Here, we design a facile method to deliver drugs to the skin through microneedles (MNs) to stimulate the immune system in two ways. As one of the tumor vaccines, cancer cell membrane proteins can act as tumor-specific antigens that are presented to antigen presenting cells (APCs) to activate the immune system. In addition, a toll-like receptor 7 (TLR7) agonist of imiquimod (R837) can suppress cancer cell growth by inhibiting angiogenesis. Using poloxamer 407 (F127) as a nanocarrier, F127 nanoparticles (F127 NPs) are loaded with R837 and then coated with cancer cell membranes (M). These F127-R837@M NPs are loaded in rapidly dissolving MNs and delivered through the skin. MNs loaded with F127-R837@M NPs show significant inhibition of cancer cell growth in both prophylactic vaccination and antitumor immunotherapy in vivo. The dual immune system stimulating F127-R837@M NPs could be effectively used for cancer immunotherapy.

Assessing the capacity for mental manipulation in patients with statically-determined mild cognitive impairment using digital technology

Aims: Prior research employing a standard backward digit span test has been successful in operationally defining neurocognitive constructs associated with the Fuster’s model of executive attention. The current research sought to test if similar behavior could be obtained using a cross-modal mental manipulation test. Methods: Memory clinic patients were studied. Using Jak-Bondi criteria, 24 patients were classified with mild cognitive impairment (MCI), and 33 memory clinic patients did not meet criteria for MCI (i.e. non-MCI). All patients were assessed with the digital version of the WRAML-2 Symbolic Working Memory Test-Part 1, a cross-modal mental manipulation task where patients hear digits, but respond by touching digits from lowest to highest on an answer key. Only 4 and 5-span trials were analyzed. Using an iPad, all test stimuli were played; and, all responses were obtained with a touch key. Only correct trials were analyzed. Average time to complete trials and latency for each digit was recorded. Results: Groups did not differ when average time to complete 4-span trials was calculated. MCI patients displayed slower latency, or required more time to re-order the 1st and 3rd digits. Regression analyses, primarily involving initial and latter response latencies, were associated with better, but different underlying neuropsychological abilities. Almost no 5-span analyses were significant. Conclusions: This cross-modal test paradigm found no difference for total average time. MCI patients generated slower 1st and 3rd response latency, suggesting differences in time allocation to achieve correct serial order recall. Moreover, different neuropsychological abilities were associated with different time-based test components. These data extend prior findings using a standard backward digit span test. Differences in time epochs are consistent with constructs underlying the model of executive attention and help explain mental manipulation deficits in MCI. These latency measures could constitute neurocognitive biomarkers that track emergent disease.

Aptamers and antibodies: rivals or allies in cancer targeted therapy?

The goal of an efficacious cancer therapy is to specifically target diseased cells at high accuracy while sparing normal, healthy cells. Over the past three decades, immunotherapy, based on the use of monoclonal antibodies (mAbs) directed against tumor-associated antigens, to inhibit their oncogenic function, or against immune checkpoints, to modulate specific T cell responses against cancer, has proven to be an important strategy for cancer therapy. Nevertheless, the number of mAbs approved for clinical use is still limited because of significant drawbacks to their applicability. Oligonucleotide aptamers, similarly to antibodies, form high-affinity bonds with their specific protein targets, thus representing an effective tool for active cancer targeting. Compared to antibodies, aptamers’ use as therapeutic agents benefits from their low size, low/no immunogenicity, simple synthesis and design flexibility for improving efficacy and stability. This review intends to highlight recently emerged applications of aptamers as recognition elements, from biomarker discovery to targeted drug delivery and targeted treatment, showing aptamers’ potential to work in conjunction with antibodies for attacking cancer from multiple flanks.

Polypeptide nanoformulation-induced immunogenic cell death and remission of immunosuppression for enhanced chemoimmunotherapy

Many conventional chemotherapeutics play an immune-modulating effect by inducing immunogenic cell death (ICD) in tumor cells. However, they hardly arouse strong antitumor immune response because the immunosuppressive lymphocytes are present in the tumor microenvironment. These immunosuppressive lymphocytes include regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs). We used a low dose of doxorubicin (DOX) to induce ICD in combination with immune regulator 1-methyl-DL-tryptophan (1MT) to suppress indoleamine 2,3-dioxygenase and overcome Treg- and MDSC-associated immune suppression. By co-encapsulation of DOX and 1MT into a reduction-responsive polypeptide nanogel, the drugs were simultaneously released in the tumor cells and synergistically performed antitumor efficacy. After treatment, recruitment of Tregs and MDSCs was inhibited, and the frequency of tumor-infiltrating CD8⁺ T cells was remarkably enhanced. These results demonstrated that the chemoimmunotherapy strategy effectively suppressed tumor growth without causing evident adverse effects, indicating its great potential in clinical cancer therapy.

Polymeric Micelles in Cancer Immunotherapy

Cancer immunotherapies have generated some miracles in the clinic by orchestrating our immune system to combat cancer cells. However, the safety and efficacy concerns of the systemic delivery of these immunostimulatory agents has limited their application. Nanomedicine-based delivery strategies (e.g., liposomes, polymeric nanoparticles, silico, etc.) play an essential role in improving cancer immunotherapies, either by enhancing the anti-tumor immune response, or reducing their systemic adverse effects. The versatility of working with biocompatible polymers helps these polymeric nanoparticles stand out as a key carrier to improve bioavailability and achieve specific delivery at the site of action. This review provides a summary of the latest advancements in the use of polymeric micelles for cancer immunotherapy, including their application in delivering immunological checkpoint inhibitors, immunostimulatory molecules, engineered T cells, and cancer vaccines.

Nanomaterials-Mediated Immunomodulation for Cancer Therapeutics

Immunotherapy holds great promise in overcoming the limitations of conventional regimens for cancer therapeutics. There is growing interest among researchers and clinicians to develop novel immune-strategies for cancer diagnosis and treatment with better specificity and lesser adversity. Immunomodulation-based cancer therapies are rapidly emerging as an alternative approach that employs the host’s own defense mechanisms to recognize and selectively eliminate cancerous cells. Recent advances in nanotechnology have pioneered a revolution in the field of cancer therapy. Several nanomaterials (NMs) have been utilized to surmount the challenges of conventional anti-cancer treatments like cytotoxic chemotherapy, radiation, and surgery. NMs offer a plethora of exceptional features such as a large surface area to volume ratio, effective loading, and controlled release of active drugs, tunable dimensions, and high stability. Moreover, they also possess the inherent property of interacting with living cells and altering the immune responses. However, the interaction between NMs and the immune system can give rise to unanticipated adverse reactions such as inflammation, necrosis, and hypersensitivity. Therefore, to ensure a successful and safe clinical application of immunomodulatory nanomaterials, it is imperative to acquire in-depth knowledge and a clear understanding of the complex nature of the interactions between NMs and the immune system. This review is aimed at providing an overview of the recent developments, achievements, and challenges in the application of immunomodulatory nanomaterials (iNMs) for cancer therapeutics with a focus on elucidating the mechanisms involved in the interplay between NMs and the host’s immune system.

Immune Modulator and Low-Temperature PTT-Induced Synergistic Immunotherapy for Cancer Treatment

Immunotherapy has shown great potential in cancer therapeutics but has limitations of the insufficient activation of dendritic cells (DCs) and immune-suppressive microenvironment. To overcome these obstacles, a cascade synergistic immunotherapy nanosystem (denoted as CpG@PDA-FA) was designed to elevate anticancer immune response. The combination nanosystem including a photothermal agent polydopamine (PDA) and immunomodulator CpG oligodeoxynucleotides (CpG ODNs). On the one hand, polydopamine (PDA) acts as a photothermal agent to induce low-temperature PTT. It leads to immunogenic cell death (ICD), a programmed cell death pathway, which can activate DCs and enhance the antitumor immune response of T cells. On the other hand, CpG ODNs further promote maturation and migration of DCs as well as ameliorates the immunosuppression microenvironment of the tumor (TME). This paper focuses on a cancer synergistic treatment of ICD-induced immunotherapy by low-temperature PTT and ameliorates TME by immunomodulator CpG ODNs. We proved that CpG@PDA-FA NPs realized a remarkable synergistic treatment effect compared with respective single PTT or CpG therapy in the maturation of DCs and activation of T cells. In addition, CpG@PDA-FA NPs also reduced myeloid-derived suppressor cells and regulatory T cells to relieve immunosuppression. Hence, CpG@PDA-FA NPs provide a bidirectional immunotherapy strategy for tumor inhibition and highlight the cascade effects of low-temperature PTT and immunotherapy.

In vivo Therapeutic Effects and Mechanisms of Hydroxyasiaticoside Combined With Praziquantel in the Treatment of Schistosomiasis Induced Hepatic Fibrosis

Schistosomiasis has been a fatal obstinate disease that threatens global human health, resulting in the granulomatous inflammation and liver fibrosis. Objective:The aim of this study was to evaluate the therapeutic effects and mechanisms of hydroxyasiaticoside combined with praziquantel in the treatment of schistosomiasis-induced liver fibrosis. Methods:Mice were randomly distributed into four experimental groups: normal control group, model group, praziquantel group, praziquantel + hydroxyasiaticoside group. Except for the normal control group, they were infected with Schistosomia cercariae through the abdominal skin to induce liver fibrosis. In the intervention group, mice were administered with the respective drugs by gavage after 8 weeks of infection. At the end of the treatment, mice were sacrificed to collect blood for the determination of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) serum levels. Moreover, the liver was excised, weighed, and liver indices were calculated. Histopathological examination was performed to assess liver morphology. Besides, the expression of collagen type I and III in liver was determined; the mRNA expression levels of IL-6 and TNF-α in liver tissues were measured using Real-time PCR while ELISA and western blotting were performed on liver tissue homogenate to determine the protein expression of IL-6 and TNF-α. Results:The combination of praziquantel and hydroxyasiaticoside lowered the pathological scores of schistosomiasis-induced hepatic fibrosis, the liver indice, serum AST and ALT levels, improved liver morphology, downregulated the expression levels of hepatic type I and III collagen, inhibited the mRNA expression levels of pro-inflammatory factors (IL-6 and TNF-α) in the liver of mice relative to the praziquantel alone. Conclusion:The combination of hydroxyasiaticoside and praziquantel is a potential therapeutic option for schistosomiasis-induced hepatic fibrosis. Notably, this combination noticeably suppresses the protein and mRNA expression levels of pro-inflammatory factors (TNF-α and IL-6) in the liver.

Particulate-Based Single-Dose Local Immunosuppressive Regimen for Inducing Tolerogenic Dendritic Cells in Xenogeneic Islet Transplantation

Recent studies emphasize on developing immune tolerance by an interim administration of various immunosuppressive drugs. In this study, a robust protocol is reported for local immunomodulation using a single-dose of FK506 microspheres and clodronate liposomes (mFK+CLO) in a xenogeneic model of islet transplantation. Surprisingly, the single-dose treatment with mFK+CLO induce tolerance to the islet xenograft. The recipient mice display tolerogenic dendritic cells (tDCs) with decreased antigen presenting ability and T cell activation capacity. Furthermore, a reduced percentage of CD4⁺ and CD8⁺ T cells and an impaired differentiation of naïve CD4⁺ T cells into interferon-γ producing Th1 and interleukin-17 producing Th17 cells are observed. In addition, the immunosuppressive protocol leads to the generation of Foxp3⁺ regulatory T cells (Tregs) which are required for the long-term graft survival. The enhanced generation of tDCs and Tregs by the single treatment of mFK+CLO cause xenograft tolerance, suggesting a possible clinical strategy which may pave the way towards improving therapeutic outcomes of clinical islet transplantation.

Nanotools for Sepsis Diagnosis and Treatment

Sepsis is one of the leading causes of death worldwide with high mortality rates and a pathological complexity hindering early and accurate diagnosis. Today, laboratory culture tests are the epitome of pathogen recognition in sepsis. However, their consistency remains an issue of controversy with false negative results often observed. Clinically used blood markers, C reactive protein (CRP) and procalcitonin (PCT) are indicators of an acute-phase response and thus lack specificity, offering limited diagnostic efficacy. In addition to poor diagnosis, inefficient drug delivery and the increasing prevalence of antibiotic-resistant microorganisms constitute significant barriers in antibiotic stewardship and impede effective therapy. These challenges have prompted the exploration for alternative strategies that pursue accurate diagnosis and effective treatment. Nanomaterials are examined for both diagnostic and therapeutic purposes in sepsis. The nanoparticle (NP)-enabled capture of sepsis causative agents and/or sepsis biomarkers in biofluids can revolutionize sepsis diagnosis. From the therapeutic point of view, currently existing nanoscale drug delivery systems have proven to be excellent allies in targeted therapy, while many other nanotherapeutic applications are envisioned. Herein, the most relevant applications of nanomedicine for the diagnosis, prognosis, and treatment of sepsis is reviewed, providing a critical assessment of their potentiality for clinical translation.

Anti-rheumatic effect of quercetin and recent developments in nano formulation

Quercetin is a potential anti-rheumatoid drug. Nano formulation strategies could improve its solubility and efficacy.

Biomimetic Anti-PD-1 Peptide-Loaded 2D FePSe3 Nanosheets for Efficient Photothermal and Enhanced Immune Therapy with Multimodal MR/PA/Thermal Imaging

Metal phosphorous trichalcogenides (MPX3) are novel 2D nanomaterials that have recently been exploited as efficient photothermal-chemodynamic agents for cancer therapy. As a representative MPX3, FePSe3 has the potential to be developed as magnetic resonance imaging (MRI) and photoacoustic imaging (PAI) agents due to the composition of Fe and the previously revealed PA signal. Here, a FePSe3-based theranostic agent, FePSe3@APP@CCM, loaded with anti-PD-1 peptide (APP) as the inner component and CT26 cancer cell membrane (CCM) as the outer shell is reported, which acts as a multifunctional agent for MR and PA imaging and photothermal and immunotherapy against cancer. FePSe3@APP@CCM induces highly efficient tumor ablation and suppresses tumor growth by photothermal therapy under near-infrared laser excitation, which further activates immune responses. Moreover, APP blocks the PD-1/PD-L1 pathway to activate cytotoxic T cells, causing strong anticancer immunity. The combined therapy significantly prolongs the lifespan of experimental mice. The multimodal imaging and synergistic therapeutic effects of PTT and its triggered immune responses and APP-related immunotherapy are clearly demonstrated by in vitro and in vivo experiments. This work demonstrates the potential of MPX3-based biomaterials as novel theranostic agents.

Self-Delivery Photo-Immune Stimulators for Photodynamic Sensitized Tumor Immunotherapy

Self-delivery of photosensitizer and immune modulator to tumor site is highly recommendable to improve the photodynamic immunotherapy yet remains challenging. Herein, self-delivery photoimmune stimulators (designated as iPSs) are developed for photodynamic sensitized tumor immunotherapy. Carrier-free iPSs are constructed by optimizing the noncovalent interactions between the pure drugs of chlorine e6 (Ce6) and NLG919, which avoid the excipients-raised toxicity and immunogenicity. Intravenously administrated iPSs prefer to passively accumulate on tumor tissues for a robust photodynamic therapy (PDT) with the induction of immunogenetic cell death (ICD) cascade to activate cytotoxic T lymphocytes (CTLs) and initiate antitumor immune response. Meanwhile, the concomitant delivery of NLG919 inhibits the activation of indoleamine 2,3-dioxygenase 1 (IDO-1) to reverse the immunosuppressive tumor microenvironment. Ultimately, the photodynamic sensitized immunotherapy with iPSs efficiently inhibit the primary and distant tumor growth with a low system toxicity, which would shed light on the development of self-delivery nanomedicine for clinical transformation in tumor precision therapy.

Pembrolizumab Induces an Unexpected Conformational Change in the CC'-loop of PD-1

Simple Summary

Cancer cells are normally destructed by killer T-cells. However, T-cells expose the PD-1 receptor on their surface, acting as a checkpoint: If it is activated through a special molecule, PD-L1, the T-cell kills itself, ending the attack. Cells often need to present PD-L1 to prevent T-cells from over-aggressive attacks which cause autoimmune disease. There are tumors which also present PD-L1, thereby evading natural clearing, allowing them to continue growing. New anticancer drugs (checkpoint inhibitors: nivolumab and pembrolizumab) disrupt this evasion: They competitively bind to PD-1, without activating it, and re-enable immune tumor destruction. We scrutinize the binding mechanisms via molecular dynamics simulation. We demonstrate that these drugs deform the CC′-loop of the PD-1 in ways differing from those seen with PD-L1 as a binding partner. Pembrolizumab induces a new conformation of the CC′-loop not known to date. These findings might pave the way for the development of new anti-cancer drugs.

Abstract

To improve cancer immunotherapy, a clearer understanding of key targets such as the immune checkpoint receptor PD-1 is essential. The PD-1 inhibitors nivolumab and pembrolizumab were recently approved by the FDA. The CC′-loop of PD-1 has been identified as a hotspot for drug targeting. Here, we investigate the influence of nivolumab and pembrolizumab on the molecular motion of the CC′-loop of PD-1. We performed molecular dynamics simulations on the complete extracellular domain of PD-1, in complex with PD-L1, and the blocking antibodies nivolumab and pembrolizumab. Conformations of the CC′-loop were analyzed unsupervised with the Daura et al. clustering algorithm and multidimensional scaling. Surprisingly, two conformations found were seen to correspond to the ‘open’ and ‘closed’ conformation of CC′-loop in apo-PD-1, already known from literature. Unsupervised clustering also surprisingly reproduced the natural ligand, PD-L1, exclusively stabilizing the ‘closed’ conformation, as also known from literature. Nivolumab, like PD-L1, was found to shift the equilibrium towards the ‘closed’ conformation, in accordance with the conformational selection model. Pembrolizumab, on the other hand, induced a third conformation of the CC′-loop which has not been described to date: Relative to the conformation ‘open’ the, CC′-loop turned 180° to form a new conformation which we called ‘overturned’. We show that the combination of clustering and multidimensional scaling is a fast, easy, and powerful method in analyzing structural changes in proteins. Possible refined antibodies or new small molecular compounds could utilize the flexibility of the CC′-loop to improve immunotherapy.

Cucurbituril-Oriented Nanoplatforms in Biomedical Applications

Cucucrbituril (CB) belongs to a family of macrocycles that are easily accessible. Their structural specificity provides excellent molecular recognition capabilities, with the ability to be readily chemically modified. Because of these properties, researchers have found CB to be a useful molecular carrier for delivering drug molecules and therapeutic biomolecules. Their significance lies in the fact that CB not only increases the solubility and stability of an encapsulated guest but also provides the possibility to achieve targeted delivery of the guest molecule. Therefore, the emergence of CB undoubtedly provides opportunities for the development of targeted drug delivery in an era where intelligent drugs have attracted considerable attention. It has also been found that CB can enhance fluorescent dyes, allowing the preparation of biosensors with enhanced sensitivity for use in clinical settings. In the present review, the acquisition, properties, and structural modifications of CB are first comprehensively described, and then the value of this macrocycle in applications within the medical field is discussed. In addition, we have also summarized patent applications of CB in this field over recent years, aiming to illustrate the current status of developments of this molecule. Finally, we discuss the challenges faced by CB in the medical field and future trends in its development.

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.

Research Progress and Prospect of Nanoplatforms for Treatment of Oral Cancer

Oral cancers refer to malignant tumors associated with high morbidity and mortality, and oral squamous cell carcinoma accounts for the majority of cases. It is an important part of head and neck, and oral cancer is one of the six most common cancers in the world. At present, the traditional treatment methods for oral cancer include surgery, radiation therapy, and chemotherapy. However, these methods have many disadvantages. In recent years, nanomedicine, the delivery of drugs through nanoplatforms for the treatment of cancer, has become a promising substitutive therapy. The use of nanoplatforms can reduce the degradation of the drug in the body and accurately deliver it to the tumor site. This minimizes the distribution of the drug to other organs, thereby reducing its toxicity and allowing higher drug concentration at the tumor site. This review introduces polymer nanoparticles, lipid-based nanoparticles, metal nanoparticles, hydrogels, exosomes, and dendrimers for the treatment of oral cancer, and discusses how these nanoplatforms play an anti-cancer effect. Finally, the review gives a slight outlook on the future prospects of nanoplatforms for oral cancer treatment.

Fluorine assembly nanocluster breaks the shackles of immunosuppression to turn the cold tumor hot

Clinical investigations have shown that a nonimmunogenic "cold" tumor is usually accompanied by few immunopositive cells and more immunosuppressive cells in the tumor microenvironment (TME), which is still the bottleneck of immune activation. Here, a fluorine assembly nanocluster was explored to break the shackles of immunosuppression, reawaken the immune system, and turn the cold tumor "hot." Once under laser irradiation, FS@PMPt produces sufficient reactive oxygen species (ROS) to fracture the ROS-sensitive linker, thus releasing the cisplatin conjugated PMPt to penetrate into the tumors and kill the regulatory T cells (Tregs) and myeloid-derived suppressor cells (MDSCs). Meanwhile, ROS will induce potent immunogenic cell death (ICD) and further promote the accumulation of dendritic cells (DCs) and T cells, therefore not only increasing the infiltration of immunopositive cells from the outside but also reducing the immunosuppressive cells from the inside to break through the bottleneck of immune activation. The FS@PMPt nanocluster regulates the immune process in TME from negative to positive, from shallow to deep, to turn the cold tumor into a hot tumor and provoke a robust antitumor immune response.

Modulating barriers of tumor microenvironment through nanocarrier systems for improved cancer immunotherapy: a review of current status and future perspective

Cancer immunotherapy suppresses and destroys tumors by re-activating and sustaining the tumor-immune process, and thus improving the immune response of the body to the tumor. Immunotherapeutic strategies are showing promising results in pre-clinical and clinical trials, however, tumor microenvironment (TME) is extremely immunosuppressive. Thus, their translation from labs to clinics still faces issues. Recently, nanomaterial-based strategies have been developed to modulate the TME for robust immunotherapeutic responses. The combination of nanotechnology with immunotherapy potentiates the effectiveness of immunotherapy by increasing delivery and retention, and by reducing immunomodulation toxicity. This review aims to highlight the barriers offered by TME for hindering the efficiency of immunotherapy for cancer treatment. Next, we highlight various nano-carriers based strategies for modulating those barriers for achieving better therapeutic efficacy of cancer immunotherapy with higher safety. This review will add to the body of scientific knowledge and will be a good reference material for academia and industries.

Engineering the drug carrier biointerface to overcome biological barriers to drug delivery

Micro and nanoscale drug carriers must navigate through a plethora of dynamic biological systems prior to reaching their tissue or disease targets. The biological obstacles to drug delivery come in many forms and include tissue barriers, mucus and bacterial biofilm hydrogels, the immune system, and cellular uptake and intracellular trafficking. The biointerface of drug carriers influences how these carriers navigate and overcome biological barriers for successful drug delivery. In this review, we examine how key material design parameters lead to dynamic biointerfaces and improved drug delivery across biological barriers. We provide a brief overview of approaches used to engineer key physicochemical properties of drug carriers, such as morphology, surface chemistry, and topography, as well as the development of dynamic responsive materials for barrier navigation. We then discuss essential biological barriers and how biointerface engineering can enable drug carriers to better navigate and overcome these barriers to drug delivery.

Implantable and Injectable Biomaterial Scaffolds for Cancer Immunotherapy

Cancer immunotherapy has become an emerging strategy recently producing durable immune responses in patients with varieties of malignant tumors. However, the main limitation for the broad application of immunotherapies still to reduce side effects by controlling and regulating the immune system. In order to improve both efficacy and safety, biomaterials have been applied to immunotherapies for the specific modulation of immune cells and the immunosuppressive tumor microenvironment. Recently, researchers have constantly developed biomaterials with new structures, properties and functions. This review provides the most recent advances in the delivery strategies of immunotherapies based on localized biomaterials, focusing on the implantable and injectable biomaterial scaffolds. Finally, the challenges and prospects of applying implantable and injectable biomaterial scaffolds in the development of future cancer immunotherapies are discussed.

Effects of Selenium Nanoparticles Combined With Radiotherapy on Lung Cancer Cells

Objective

To investigate the effects of selenium nanoparticles (nano-Se) combined with radiotherapy on the proliferation, migration, invasion, and apoptosis of non-small cell lung cancer (NSCLC) A549 and NCI-H23 cells.

Methods

Nano-Se was synthesized and characterized by transmission electron microscope (TEM), X-ray diffractometer, and Ultraviolet-visible (UV)-Vis Spectroscopy, separately. The uptake of nano-Se by lung cancer cells was detected by flow cytometry. Cell counting kit-8 (CCK-8) method was used to detect the antiproliferative activity of nano-Se combined with radiotherapy. Wound healing tests and transwell assay were used to detect the migration and invasion ability of the cells. Annexin V-fluorescein isothiocyanate (FITC)/Propidium iodide (PI) staining by flow cytometry was used to detect apoptosis. The expression of Cyclin D1 (CCND1), c-Myc, matrix metalloproteinase 2 (MMP2), MMP9, cleaved Caspase-3, and cleaved Caspase-9 were detected by Western blot.

Results

The average diameter of nano-Se was 24.39 nm and the wavelength of nano-Se increased with the increase of radiation dose under UV-Vis Spectroscopy. The uptake of nano-Se in lung cancer cells was increased with the increase of nano-Se concentration. The nano-Se combined with radiotherapy decreased the proliferation activity of NSCLC cell lines A549 and NCI-H23 in a dose-dependent manner (all P < 0.05). Compared with the Control group, nano-Se combined with radiotherapy could significantly inhibit the migration and invasion of lung cancer cells (all P < 0.05), and the effects of the combination of nano-Se and radiotherapy was better than that of a single application (all P < 0.05). Furthermore, nano-Se combined with radiotherapy could induce apoptosis of lung cancer cells (P < 0.05) and nano-Se combined with radiotherapy could significantly inhibit the expression of proliferation-related proteins CCND1, c-Myc, invasion and migration-related proteins MMP2 and MMP9, but conversely promoted the expression of apoptosis-related proteins cleaved caspase-3 and cleaved caspase-9. Conclusion: This study found that nano-Se combined with radiotherapy plays an anti-cancer role in lung cancer cells by inhibiting cell proliferation, migration, and invasion, as well as inducing apoptosis, suggesting that nano-Se may be used as a radiosensitizer in the clinical treatment of lung cancer, but further research is still needed.

Biomedical nanomaterials for immunological applications: ongoing research and clinical trials

Research efforts on nanomaterial-based therapies for the treatment of autoimmune diseases and cancer have spiked and have made rapid progress over the past years. Nanomedicine has been shown to contribute significantly to overcome current therapeutic limitations, exhibiting advantages compared to conventional therapeutics, such as sustained drug release, delayed drug degradation and site-specific drug delivery. Multiple nanodrugs have reached the clinic, but translation is often hampered by either low targeting efficiency or undesired side effects. Nanomaterials, and especially inorganic nanoparticles, have gained criticism due to their potential toxic effects, including immunological alterations. However, many strategies have been attempted to improve the therapeutic efficacy of nanoparticles and exploit their unique properties for the treatment of inflammation and associated diseases. In this review, we elaborate on the immunomodulatory effects of nanomaterials, with a strong focus on the underlying mechanisms that lead to these specific immune responses. Nanomaterials to be discussed include inorganic nanoparticles such as gold, silica and silver, as well as organic nanomaterials such as polymer-, dendrimer-, liposomal- and protein-based nanoparticles. Furthermore, various approaches for tuning nanomaterials in order to enhance their efficacy and attenuate their immune stimulation or suppression, with respect to the therapeutic application, are described. Additionally, we illustrate how the acquired insights have been used to design immunotherapeutic strategies for a variety of diseases. The potential of nanomedicine-based therapeutic strategies in immunotherapy is further illustrated by an up to date overview of current clinical trials. Finally, recent efforts into enhancing immunogenic cell death through the use of nanoparticles are discussed.

Pranoprofen Nanoparticles With Poly(L-Lactide)-b-Poly(Ethylene Glycol)-b-Poly(L-Lactide) as the Matrix Toward Improving Ocular Anti-inflammation

Nanotechnology using biodegradable polymer carriers with good biocompatibility and bioabsorbability has been studied and applied extensively in drug delivery systems and biomedical engineering. In this work, the triblocked oligomer poly(L-lactide)-b-poly(ethylene glycol)-b-poly(L-lactide) (PLEL) with the molecular weight of 2.08 KDa was first synthesized. Its chemistry was characterized by hydrogen nuclear magnetic resonance (1H-NMR) spectrum and Fourier transform infrared (FTIR) spectroscopy. Subsequently, the nanoparticles (NPs) of PLEL and pranoprofen (PF)-loaded PLEL were prepared with the average particle size of (151.7 ± 5.87) nm using the method of emulsion solvent evaporation. The formula and drug releasing profile were characterized by a transmission electron microscope (TEM), dynamic light scattering (DLS), and ultraviolet spectrophotometer (US). In vitro cytotoxicity assays and in vivo ophthalmic tests were performed to measure the safety and efficacy of the formulations. The results showed that PF NPs relieved the cytotoxicity of pure PF and eliminated ophthalmic irritation. The drug encapsulated in the nanoparticles displayed long-lasting release and good anti-inflammation efficiency in animal eyes. Therefore, we concluded that the present formula (PF NPs) could provide sustained drug release with good treatment effect on eye inflammation, and is promising for its use in ophthalmology in the future.

Oxyresveratrol induces apoptosis and inhibits cell viability via inhibition of the STAT3 signaling pathway in Saos‑2 cells

Oxyresveratrol (ORES) is a natural phenolic compound with multiple biological functions including antioxidation, anti-inflammation and neuroprotection; however, the inhibitory effect of ORES on osteosarcoma remains largely unknown. The present study aimed to determine the effects of ORES on osteosarcoma cell Saos-2. Cell Counting Kit-8 assay was performed to detect Soas-2 cell viability. Annexin-FITC/PI staining and JC-1 staining were used to measure cell apoptosis and the change of mitochondrial membrane potential. In addition, western blotting was conducted to determine the expression levels of apoptotic proteins and the phosphorylation of STAT3. It was found that ORES inhibited cell viability and induced apoptosis of osteosarcoma Saos-2 cells in a concentration-dependent manner. In addition, ORES increased the expression levels of apoptotic proteases caspase-9 and caspase-3 and reduced mitochondrial membrane potential. In response to ORES treatment, the expression levels of pro-apoptotic proteins, Bad and Bax, were enhanced, whereas those of anti-apoptotic proteins, Bcl-2 and Bcl-xL, were reduced. In addition, the phosphorylation of STAT3 was attenuated in Saos-2 cells after treatment with ORES. Inhibition of cell viability and apoptosis induction by ORES were rescued by enhancement of STAT3 activation upon treatment with IL-6. Collectively, the present study indicated that ORES induced apoptosis and inhibited cell viability, which may be associated with the inhibition of STAT3 activation; thus, ORES represents a promising agent for treating osteosarcoma.

Tolerogenic Immunomodulation by PEGylated Antigenic Peptides

Current treatments for autoimmune disorders rely on non-specific immunomodulatory and global immunosuppressive drugs, which show a variable degree of efficiency and are often accompanied by side effects. In contrast, strategies aiming at inducing antigen-specific tolerance promise an exclusive specificity of the immunomodulation. However, although successful in experimental models, peptide-based tolerogenic "inverse" vaccines have largely failed to show efficacy in clinical trials. Recent studies showed that repetitive T cell epitopes, coupling of peptides to autologous cells, or peptides coupled to nanoparticles can improve the tolerogenic efficacy of peptides, suggesting that size and biophysical properties of antigen constructs affect the induction of tolerance. As these materials bear hurdles with respect to preparation or regulatory aspects, we wondered whether conjugation of peptides to the well-established and clinically proven synthetic material polyethylene glycol (PEG) might also work. We here coupled the T cell epitope OVA323-339 to polyethylene glycols of different size and structure and tested the impact of these nano-sized constructs on regulatory (Treg) and effector T cells in the DO11.10 adoptive transfer mouse model. Systemic vaccination with PEGylated peptides resulted in highly increased frequencies of Foxp3+ Tregs and reduced frequencies of antigen-specific T cells producing pro-inflammatory TNF compared to vaccination with the native peptide. PEGylation was found to extend the bioavailability of the model peptide. Both tolerogenicity and bioavailability were dependent on PEG size and structure. In conclusion, PEGylation of antigenic peptides is an effective and feasible strategy to improve Treg-inducing, peptide-based vaccines with potential use for the treatment of autoimmune diseases, allergies, and transplant rejection.

Immunoadjuvants for cancer immunotherapy: A review of recent developments

Cancer immunotherapy evolved as a new treatment modality to eradicate tumor cells and has gained in popularity after its successful clinical transition. By activating antigen-presenting cells (APCs), and thus, inducing innate or adaptive immune responses, immunoadjuvants have become promising tools for cancer immunotherapy. Different types of immunoadjuvants such as toll-like receptor (TLR) agonists, exosomes, and metallic and plant-derived immunoadjuvants have been studied for their immunological effects. However, the clinical use of immunoadjuvants is limited by short response rates and various side-effects. The rapid progress made in the development of nanoparticle systems as immunoadjuvant carrier vehicles has provided potential carriers for cancer immunotherapy. In this review article, we describe different types of immunoadjuvants, their limitations, modes of action, and the reasons for their clinical adoption. In addition, we review recent progress made in the nanoparticle-based immunoadjuvant field and on the combined use of nanoparticle-based immunoadjuvants and chemotherapy, phototherapy, radiation therapy, and immune checkpoint inhibitor-based therapy. STATEMENT OF SIGNIFICANCE: Cancer immunotherapy emerged as a new hope for treating malignant tumors. Different types of immunoadjuvants serve as an important tool for cancer immunotherapy by activating an innate or adaptive immune response. Limitation of free immunoadjuvant has paved the path for the development of nanoparticle-based immunoadjuvant therapy with the hope of prolonging the therapeutic efficacy. This review highlights the recent advancement made in nanoparticle-based immunoadjuvant therapy in modulating the adaptive and innate immune system. The application of the combinatorial approach of chemotherapy, phototherapy, radiation therapy adds synergy in nanoparticle-based immunoadjuvant therapy. It will broaden the reader's understanding on the recent progress made in immunotherapy with the aid of immunoadjuvant-based nanosystem.

Smart Nanosized Drug Delivery Systems Inducing Immunogenic Cell Death for Combination with Cancer Immunotherapy

Cancer immunotherapy, which suppresses tumor relapse and metastasis by boosting host immunity and inducing long-term immune memory effects, is emerging as a vital approach to improve the prognosis of patients. Although remarkable efficacy has been observed in some patients, challenges including low response rate, drug resistance, and immune-related adverse effects still limit the clinical application of cancer immunotherapy in broad types of tumors. Immunotherapeutic agents are used to enhance tumor immunogenicity and reverse the effects of the immunosuppressive tumor microenvironment (ITM), but the benefits of monotherapy are mild and transient due to off-target distribution of drugs. To overcome these issues, smart nanosized drug delivery systems (sNDDS) have been developed to enhance tissue specificity, co-deliver multiple drugs, prime immune cells, and amplify immune responses in tumors. Moreover, accumulating knowledge in cancer biology, immunology, and material science has also greatly promoted the development of sNDDS for enhancing cancer immunotherapy.In this Account, we will discuss the approaches of our group in designing sNDDS to induce immunogenic cell death (ICD) for combination with cancer immunotherapy. We propose a brief overview on the design of nanocarriers, intelligent moieties and immunotherapeutic agents in sNDDS. Then, we discuss the strategies to remodel ITM by leveraging ICD as well as cooperating with programmed cell death protein 1 ligand blockade and indoleamine 2,3-dioxygenase 1 inhibition. We have synthesized a series of stimuli-responsive polymers and prodrugs to fabricate sNDDS and have integrated multiple immunotherapeutic drugs into one platform for combinational immunotherapy. Last, we present an outlook on future design of sNDDS and possible directions for enhancing cancer immunotherapy. Building on the concept of enhancing tumor immunogenicity and reversing ITM, we hope this Account will contribute to the rational design of sNDDS for co-delivery of multiple drugs with amplified immunotherapeutic efficacy.

Rational Design of a Robust Antibody-like Small-Molecule Inhibitor Nanoplatform for Enhanced Photoimmunotherapy

Immune checkpoint blockade of the programmed cell death-ligand 1/programmed cell death-1 (PD-L1/PD-1) pathway via an antibody is a potent strategy for T cell remodeling. Nevertheless, the potency of the antibody is partly compromised by its high price, instability, risk of autoimmune disease, and so forth. Small-molecule inhibitors are interesting alternatives to antibodies. However, tumor-specific delivery of small-molecule inhibitors to the target site for boosting the interruption of the PD-L1/PD-1 pathway is rarely reported. Herein, we designed a tumor-specific delivery nanoplatform that could efficiently deliver the small-molecule inhibitor to the precise target site, greatly enhancing the blocking effect of the PD-L1/PD-1 pathway. Hyaluronic acid (HA) was conjugated with chlorin e6 (Ce6), resulting in a HA-Ce6 conjugate (HC). The nanoplatform was constructed by the HC micelles with the encapsulation of small-molecule inhibitor, BMS 202 (BMS), to form BMS/HC micelles. The target property of HA, combined with the hyaluronidase-induced degradation of HA in the tumor site, enables the as-prepared micelles with tumor-specific delivery of BMS for blocking the PD-L1/PD-1 pathway. With cooperative treatment with the photosensitizer Ce6, the present therapeutic nanoplatform demonstrated excellent photoimmunotherapy for tumor regression in distant tumors and lung metastasis. This strategy of tumor-specific delivery of small-molecule inhibitors provides an effective pathway to strengthen the blocking efficacy of PD-L1/PD-1 on effective photoimmunotherapy.

Co-delivery of Peptide Neoantigens and Stimulator of Interferon Genes Agonists Enhances Response to Cancer Vaccines

Cancer vaccines targeting patient-specific neoantigens have emerged as a promising strategy for improving responses to immune checkpoint blockade. However, neoantigenic peptides are poorly immunogenic and inept at stimulating CD8⁺ T cell responses, motivating a need for new vaccine technologies that enhance their immunogenicity. The stimulator of interferon genes (STING) pathway is an endogenous mechanism by which the innate immune system generates an immunological context for priming and mobilizing neoantigen-specific T cells. Owing to this critical role in tumor immune surveillance, a synthetic cancer nanovaccine platform (nanoSTING-vax) was developed that mimics immunogenic cancer cells in its capacity to efficiently promote co-delivery of peptide antigens and the STING agonist, cGAMP. The co-loading of cGAMP and peptides into pH-responsive, endosomolytic polymersomes promoted the coordinated delivery of both cGAMP and peptide antigens to the cytosol, thereby eliciting inflammatory cytokine production, co-stimulatory marker expression, and antigen cross-presentation. Consequently, nanoSTING-vax significantly enhanced CD8⁺ T cell responses to a range of peptide antigens. Therapeutic immunization with nanoSTING-vax, in combination with immune checkpoint blockade, inhibited tumor growth in multiple murine tumor models, even leading to complete tumor rejection and generation of durable antitumor immune memory. Collectively, this work establishes nanoSTING-vax as a versatile platform for enhancing immune responses to neoantigen-targeted cancer vaccines.

Stannic Oxide Nanoparticle Regulates Proliferation, Invasion, Apoptosis, and Oxidative Stress of Oral Cancer Cells

Objective

To explore the effects of SnO₂ nanoparticles (NPs) on proliferation, invasion, apoptosis, and oxidative stress of oral cancer.

Methods

SnO₂ NPs were prepared and characterized. Oral cancer cell lines CAL-27 and SCC-9 were cultured in vitro. We detected the effects of various concentrations of SnO₂ NPs (0, 5, 25, 50, 100, 200 μg/mL) on the proliferation of oral cancer cells, and observed the morphological changes, and measured the cells ability of migration, invasion and apoptosis condition, and the levels of oxidative stress were measured by detecting malondialdehyde (MDA) and reactive oxygen species (ROS). Besides, we also measured the changes of mRNA and protein levels of factors related to cell proliferation, migration, invasion, apoptosis, and oxidative stress.

Results

SnO₂ NPs inhibited the proliferation of oral cancer cells in a concentration-dependent manner (all P < 0.05). And SnO₂ NPs treatment could reduce the migration and invasion ability of cells (all P < 0.05), induce apoptosis, and those effects were better when treated for 48 h than 24 h (all P < 0.05). And SnO₂ NPs could induce oxidative stress in cells (all P < 0.05). Besides, the concentrations of cyclin-D1, C-myc, matrix MMP-9, and MMP-2 in SnO₂ NPs treated group was decreased (all P < 0.05), and the expression levels of cleaved Caspase-3, cleaved Caspase-9, and Cytochrome C were increased (all P < 0.05).

Conclusion

In the present study, we found that SnO₂ NPs could play a cytotoxic role in oral cancer cells, and inhibit cell proliferation, migration, and invasion, and induce oxidative stress and apoptosis, which suggests that SnO₂ NPs may have the effects of anti-oral cancer. However, a more in-depth study is needed to determine its roles.

Liposome-Based Bioassays

This review highlights the potential of using liposomes in bioassays. Liposomes consist of nano- or micro-sized, synthetically constructed phospholipid vesicles. Liposomes can be loaded with a number of reporting molecules that allow a dramatic amplification of the detection threshold in bioassays. Liposome-based sensors bind or react with the biological components of targets through the introduction of properly tailored vectors anchored on their external surface. The use of liposome-based formulations allows the set-up of bioassays that are rapid, sensitive, and often suitable for in-field applications. Selected applications in the field of immunoassays, as well as recognition/assessment of corona proteins, nucleic acids, exosomes, bacteria, and viruses are surveyed. The role of magnetoliposomes is also highlighted as an additional tool in the armory of liposome-based systems for bioassays.

Co-assembled Supramolecular Nanofibers With Tunable Surface Properties for Efficient Vaccine Delivery

The utilization of nanotechnology to deliver vaccines and modulate immunity has shown great potential in cancer therapy. Peptide-based supramolecular hydrogels as novel vaccine adjuvants have been found to effectively improve the immune response and tumor curative effect. In this study, we designed a set of reduction-responsive self-assembled peptide precursors (Fbp-G^DF^DF^DY^D(E, S, or K)-ss-ERGD), which can be reduced by glutathione (GSH) into Fbp-G^DF^DF^DY^D(E, S or K)-SH for forming of hydrogel with different surface properties (E-gel, S-gel, and K-gel, respectively). Using the same method, co-assembled hydrogel vaccines (E-vac, S-vac, and K-vac, respectively) can also be prepared by mixing different precursors with antigens before GSH reduction. Through TEM observation of the nanostructure, we found that all the co-assembled hydrogels, especially K-vac, possessed much denser and more unified nanofiber networks as compared with antigen-free hydrogels, which were very suitable for antigen storage and vaccine delivery. Although the three peptides adopted similar β-sheet secondary structures, the mechanical properties of their resulted co-assembled hydrogel vaccines were obviously different. Compared to E-vac, S-vac had a much weaker mechanical property, while K-vac had a much higher. In vivo experiments, co-assembled hydrogel vaccines, especially K-vac, also promoted antibody production and anti-tumor immune responses more significantly than the other two vaccines. Our results demonstrated that co-assembled hydrogels formed by peptides and antigens co-assembly could act as effective vaccine delivery systems for boosting antibody production, and different immune effects can be acquired by tuning the surface properties of the involved self-assembling peptides.

Carrier-Free Small-Molecule Drug Nanoassembly Elicits Chemoimmunotherapy via Co-inhibition of PD-L1/mTOR

The growth and progression of tumor are promoted by multiple cytokines, which are overactivated in the tumor microenvironment. Co-inhibiting the activities of these cytokines is expected to realize the enhanced therapeutic outcome of cancer. However, reasonable combinational strategies are still limited. Herein, a nanoassembly structure that was totally formed by the assembly of small-molecule inhibitors is constructed for the co-inhibition of mTOR and PD-L1. Together with the NIR dye IR783, Rapa and (+)-JQ1 assemble to form a stable nanoassembly structure with controllable particle size. The JQ1/Rapa-IR783 nanoassembly efficiently downregulates the PD-L1 level as well as the level of PKM2. The combination of Rapa and (+)-JQ1 enhances the apoptosis of cancer cells compared with that following treatment with Rapa or (+)-JQ1 alone. In vivo assays conducted to evaluate tumor growth inhibition mediated by the nanoassemblies revealed that the simultaneous delivery of Rapa and (+)-JQ1 not only inhibited the growth of primary tumors but also alleviated pulmonary metastasis by reinvigorating the immune system as the result of the downregulation of both mTOR and PD-L1. It demonstrates that the nanoassembly structure is a promising candidate for the codelivery of immunomodulator for enhanced cancer immunotherapy.

Therapeutic effect of dual CAR-T targeting PDL1 and MUC16 antigens on ovarian cancer cells in mice

BACKGROUND

More favorable treatment against epithelial ovarian cancer (EOC) is urgently needed because of its insidious nature at an early stage and a low rate of five-year survival. The current primary treatment, extensive surgery combined with chemotherapy, exhibits limited benefits for improving prognosis. Chimeric antigen receptor T (CAR-T) cell technology as novel immunotherapy has made breakthrough progress in the treatment of hematologic malignancies, and there were also benefits shown in a partial solid tumor in previous research. Therefore, CAR-T cell technology may be a promising candidate as an immunotherapeutic tool against EOC. However, there are some weaknesses in targeting one antigen from the previous preclinical assay, such as on-target off-tumor cytotoxicity. The dual-target CAR-T cell may be a better choice.

METHODS

We constructed tandem PD1-antiMUC16 dual-CAR, PD1 single-CAR, and anti-MUC16 single-CAR fragments by PCR and genetic engineering, followed by preparing CAR-T cells via lentiviral infection. The expression of CAR molecules on single and dual CAR-T cells was detected by flow cytometry. The killing capacity and activation of CAR-T cells were measured by cytotoxic assays and cytokines release assays in vitro. The therapeutic capacity of CAR-T cells was assessed by tumor-bearing mice model assay in vivo.

RESULTS

We successfully constructed CARs lentiviral expression vectors and obtained single and dual CAR-T cells. CAR-T cells demonstrated robust killing capacity against OVCAR-3 cells in vitro. Meanwhile, CAR-T cells released plenty of cytokines such as interleukin-2(IL-2), interferon-γ (IFN-γ) and tumor necrosis factor-α(TNF-α). CAR-T cells showed a therapeutic benefit against OVCAR-3 tumor-bearing mice and significantly prolonged the survival time. Dual CAR-T cells were shown to be two to four times more efficacious than single CAR-T cells in terms of survival time.

CONCLUSION

Although exhibiting a similar ability as single CAR-T cells against OVCAR-3 cells in vitro, dual CAR-T cells demonstrated enhanced killing capacity against OVCAR-3 cells as compared to single CAR-T cells in vivo and significantly prolonged the survival time of tumor-bearing mice. PD1-antiMUC16 CAR-T cells showed more potent antitumor activity than single CAR-T cells in vivo. The present experimental data may support further research work that will have the potential to lead to clinical studies.

Aptamer-Functionalized Gold Nanostars for on-Demand Delivery of Anticancer Therapeutics

Gold nanostars (AuNS) are promising carriers for targeted delivery of therapeutic oligonucleotides, but their potential in fabricating an on-demand drug release system in a facile and robust way remains to be explored. In this paper, we used a model aptamer (HApt), acting not only as a target ligand but also as a natural thermal-responsive material, to decorate AuNS. The prepared gold nanoconstruct, HApt@AuNS, displayed stoichiometric loading capacity of the anthracycline drug doxorubicin (Dox). The on-demand drug release was realized by illuminating nanoconstructs with near-infrared (NIR) light. Furthermore, a higher degree of Dox release from the nanoconstructs was achieved in an acidic environment, compared to neutral conditions. The in vitro experiments showed that Dox-intercalation did not affect the cell uptake efficiency of HApt@AuNS, which could enter cells through clathrin-mediated endocytosis and microtubule-dependent active transport to lysosomes. Dox-loaded HApt@AuNS exhibited intracellular on-demand drug release and enhanced toxicity against cancer cells by NIR-irradiation.

Relieving immunosuppression during long-term anti-angiogenesis therapy using photodynamic therapy and oxygen delivery

Angiogenesis is an irreplaceable therapeutic cancer target, where anti-angiogenesis are drugs that are limited by their hydrophobicity and low therapeutic effects. What is more, the long-term shutdown of tumor blood vessel density also aggravates hypoxia and causes immunosuppression in the tumor microenvironment (TME). In order to solve these shortcomings, we developed a single therapeutic agent based on a bovine serum albumin nanocarrier that can co-deliver the anti-angiogenic drug Sorafenib ("S") and the photosensitizer Ce6 ("C") along with a molecular oxygen supply based on MnO2 ("M") as a convenient one-pot formulated nanoscale agent (SCM@BSA). Compared with anti-angiogenesis monotherapy, SCM@BSA can not only improve upon the solubility and therapeutic effects of anti-angiogenesis agents, but it also reshapes the immunosuppressive TME during anti-angiogenic therapy. Together, these results point out that SCM@BSA synthesized via a very simple method can solve the shortcomings usually experienced during long-term anti-angiogenic therapy.

Injectable Gelatin Hydrogel Suppresses Inflammation and Enhances Functional Recovery in a Mouse Model of Intracerebral Hemorrhage

Intracerebral hemorrhage (ICH) is a devastating subtype of stroke with high morbidity and mortality. However, there is no effective therapy method to improve its clinical outcomes to date. Here we report an injectable gelatin hydrogel that is capable of suppressing inflammation and enhancing functional recovery in a mouse model of ICH. Thiolated gelatin was synthesized by EDC chemistry and then the hydrogel was formed through Michael addition reaction between the thiolated gelatin and polyethylene glycol diacrylate. The hydrogel was characterized by scanning electron microscopy, porosity, rheology, and cytotoxicity before evaluating in a mouse model of ICH. The in vivo study showed that the hydrogel injection into the ICH lesion reduced the neuron loss, attenuated the neurological deficit post-operation, and decreased the activation of the microglia/macrophages and astrocytes. More importantly, the pro-inflammatory M1 microglia/macrophages polarization was suppressed while the anti-inflammatory M2 phenotype was promoted after the hydrogel injection. Besides, the hydrogel injection reduced the release of inflammatory cytokines (IL-1β and TNF-α). Moreover, integrin β1 was confirmed up-regulated around the lesion that is positively correlated with the M2 microglia/macrophages. The related mechanism was proposed and discussed. Taken together, the injectable gelatin hydrogel suppressed the inflammation which might contribute to enhance the functional recovery of the ICH mouse, making it a promising application in the clinic.

Tackling autoimmunity with nanomedicines

Tolerogenic immunotherapy aims to blunt pathogenic inflammation without affecting systemic immunity. However, the anti-inflammatory drugs and immunosuppressive biologics that are used in the clinic usually result in nonspecific immune cell suppression and off-target toxicity. For this reason, strategies have been developed to induce antigen-specific immune tolerance through the delivery of disease-relevant antigens by nanocarriers as a benefit of their preferential internalization by antigen-presenting cells. Herein, we discuss the recent advances in the nanotechnology-based antigen-specific tolerance approaches. Some of these designs are based on nanoparticles delivering antigens and immunoregulatory agents to modulate antigen-presenting pathways, while others directly target T cells via nanoparticle-based artificial antigen-presenting cells. These antigen-specific therapies are hoped to replace systemic immune suppression and provide long-term disease remission.

Recent Advances in Nanotechnology for Dendritic Cell-Based Immunotherapy

Dendritic cells (DCs) are the most important antigen-presenting cells that determine cancer immune responses by regulating immune activation and tolerance, especially in the initiation stage of specific responses. Manipulation of DCs to enhance specific antitumor immune response is considered to be a powerful tool for tumor eradication. Nanotechnology, which can incorporate multifunction components and show spatiotemporal control properties, is of great interest and is widely investigated for its ability to improve immune response activity against cancer and even for prevention and avoiding recurrence. In this mini-review, we aim to provide a general view of DC-based immunotherapy, including that involving the promising nanotechnology. Particularly we discuss: (1) manipulation or engineering of DCs for adoptive vaccination, (2) employing DCs as a combination to more existing therapeutics in tumor treatment, and (3) direct modulation of DCs in vivo to enhance antigen presentation efficacy and priming T cells subsequently. We comprehensively discuss the updates on the application of nanotechnology in DC-based immunotherapy and provide some insights on the challenges and opportunities of DC-based immunotherapeutics, including the potential of nanotechnology, against cancers.

Role and Mechanism of Rhizopus Nigrum Polysaccharide EPS1-1 as Pharmaceutical for Therapy of Hepatocellular Carcinoma

Objective: This work is to study the effect of Rhizopus nigrum polysaccharide EPS1-1 on hepatocellular carcinoma (HCC) in vitro and in vivo. Methods: HepG2 and Huh-7 cells and nude mice models of liver cancers were used in this study. The cells and nude mice were treated with EPS1-1 at different concentrations. The CCK8 assays were used to measure the proliferation activities of cells, apoptosis was determined with flow cytometry, cell migration was measured by wound-healing assays, cell invasion was evaluated by Transwell assay, and the survival periods of different groups of tumor-bearing mice were compared. Real-time PCR and Western blot were used to measure the expression levels of mRNAs and proteins of the genes related to proliferation, apoptosis, migration, and invasion. Results: In vitro experiments revealed that when treated with EPS1-1, HepG2 and Huh-7 cell proliferation activities decreased, while there was an increase for the apoptosis rate, and the migration and invasion capabilities were significantly reduced. In vivo experiments showed that EPS1-1 could significantly reduce the tumor growth and lung metastasis of HCC, and prolong the survival periods of tumor-bearing nude mice. Furthermore, EPS1-1 has no apparent damage to the heart, liver, and kidney. Further studies showed that EPS1-1 could affect the expression of proliferation-related genes CCND1 and c-Myc, apoptosis-related genes BAX and Bcl-2, and migration and invasion related genes Vimentin and Slug, thereby affecting the biological process of HCC. Conclusion: EPS1-1 can inhibit the malignant process of HCC in vitro and in vivo, which indicates that EPS1-1 has the potential value of clinical application as chemotherapy or adjuvant in the treatment of liver cancer.

Role of nanoparticle-mediated immunogenic cell death in cancer immunotherapy

Cancer immunotherapy, which suppresses cancer progression by activating the anti-cancer immunity of patients, shows utility in treating multiple types of cancers. Immunogenic cell death (ICD) induced by most clinical treatment modalities plays a critical role in promoting cancer immunotherapy by releasing tumor-associated antigens and neoantigens and exposing “danger signals” to stimulate immune cells. This comment article presents the different roles of nanoparticles in various treatment modalities of cancers, including chemotherapy, radiotherapy, photodynamic and photothermal therapies, and therapy with radiated tumor cell-released nanoparticles, which often activate anti-cancer immunological effects by inducing ICD of cancer cells, and highlights the challenges and opportunities of ICD-related cancer immunotherapy in the clinic.

Nanoenabled Disruption of Multiple Barriers in Antigen Cross-Presentation of Dendritic Cells via Calcium Interference for Enhanced Chemo-Immunotherapy

Chemo-immunotherapy holds the advantage of specific antitumor effects by activating T cell immune response. However, the efficiency of chemo-immunotherapy is restricted to the insufficient antigen presentation of dendritic cells (DCs) in the tumor immunosuppression microenvironment. Here, we rationally designed a simple yet versatile calcium ion nanogenerator to disrupt the autophagy inhibition condition within DCs, enrich damage-associated molecular patterns (DAMPs), and attenuate acidity in the tumor microenvironment. After chemotherapy, honeycomb calcium carbonate (CaCO3) nanoparticles (OVA@CaCO3, denoted as HOCN, ovalbumin (OVA) acted as skeleton) could preferentially accumulate in the tumor and display a series of benefits for disrupting multiple barriers in antigen cross-presentation of DCs: (i) recovering cell viability of DCs by HOCN-induced tumor acidity attenuating; (ii) disrupting the autophagy inhibition condition in DCs by generating Ca2+ in cells; (iii) improving maturation of DCs by Ca2+ overloading-mediated enhanced DAMP release from tumor cells. In addition, HOCN can also disrupt the immunosuppressive microenvironment by reducing the infiltration of immunosuppressive cells and factors. We believe regulation of the intratumoral Ca2+ offers an alternative strategy for improving cancer chemo-immunotherapy.

Functional Biomaterials for Treatment of Chronic Wound

The increasing number of patients with chronic wounds caused by diseases, such as diabetes, malignant tumors, infections, and vasculopathy, has caused severe economic and social burdens. The main clinical treatments for chronic wounds include the systemic use of antibiotics, changing dressings frequently, operative debridement, and flap repair. These routine therapeutic strategies are characterized by a long course of treatment, substantial trauma, and high costs, and fail to produce satisfactory results. Biomaterial dressings targeting the different stages of the pathophysiology of chronic wounds have become an active research topic in recent years. In this review, after providing an overview of the epidemiology of chronic wounds, and the pathophysiological characteristics of chronic wounds, we highlight the functional biomaterials that can enhance chronic wound healing through debridement, anti-infection and antioxidant effects, immunoregulation, angiogenesis, and extracellular matrix remodeling. It is hoped that functional biomaterials will resolve the treatment dilemma for chronic wounds and improve patient quality of life.

Absorbable Thioether Grafted Hyaluronic Acid Nanofibrous Hydrogel for Synergistic Modulation of Inflammation Microenvironment to Accelerate Chronic Diabetic Wound Healing

Current standard of care dressings are unsatisfactorily inefficacious for the treatment of chronic wounds. Chronic inflammation is the primary cause of the long-term incurable nature of chronic wounds. Herein, an absorbable nanofibrous hydrogel is developed for synergistic modulation of the inflammation microenvironment to accelerate chronic diabetic wound healing. The electrospun thioether grafted hyaluronic acid nanofibers (FHHA-S/Fe) are able to form a nanofibrous hydrogel in situ on the wound bed. This hydrogel degrades and is absorbed gradually within 3 days. The grafted thioethers on HHA can scavenge the reactive oxygen species quickly in the early inflammation phase to relieve the inflammation reactions. Additionally, the HHA itself is able to promote the transformation of the gathered M1 macrophages to the M2 phenotype, thus synergistically accelerating the wound healing phase transition from inflammation to proliferation and remodeling. On the chronic diabetic wound model, the average remaining wound area after FHHA-S/Fe treatment is much smaller than both that of FHHA/Fe without grafted thioethers and the control group, especially in the early wound healing stage. Therefore, this facile dressing strategy with intrinsic dual modulation mechanisms of the wound inflammation microenvironment may act as an effective and safe treatment strategy for chronic wound management.

Designing immunogenic nanotherapeutics for photothermal-triggered immunotherapy involving reprogramming immunosuppression and activating systemic antitumor responses

Low tumor mutational burden and absence of T cells within the tumor sites are typical characteristics of "cold immune tumors" that paralyzes the immune system. The strategy of reversing "cold tumors" to "hot tumors" infiltrated high degree of T cells in order to activate anti-tumor immunity has attracted lots of attentions. Herein, immunogenic core-shell Au@Se NPs is fabricated by gold-selenium coordination bond to realize nanoparticles-mediated local photothermal-triggered immunotherapy. As expected, incorporation of gold nanostars (AuNSs) with improved photothermal stability and conversion efficiency promotes the disintegration and transformation of selenium nanoparticles (SeNPs), thus leading to enhanced cancer cells apoptosis by producing higher hyperthermia. Moreover, the results of in vivo experiments demonstrate that the synergy between SeNPs-mediated chemotherapy and AuNSs-induced photothermal therapy not only generated a localized antitumor-immune response with excellent cancer killing effect under the presence of tumor-associated antigens, but also effectively reprogrammed the tumor associated macrophages (TAMs) from M2 to M1 phenotype with tumoricidal activity to devour distant tumors. Without a doubt, this study not only provides a potent strategy to reverse the immunosuppressive tumor microenvironment, but also offers a new insight for potential clinical application in tumor immunotherapy.