Combinational delivery of lipid-enveloped polymeric nanoparticles carrying different peptides for anti-tumor immunotherapy

Shifting cold to hot tumors by nanoparticle-loaded drugs and products

Cold tumors lack antitumor immunity and are resistant to therapy, representing a major challenge in cancer medicine. Because of the immunosuppressive spirit of the tumor microenvironment (TME), this form of tumor has a low response to immunotherapy, radiotherapy, and also chemotherapy. Cold tumors have low infiltration of immune cells and a high expression of co-inhibitory molecules, such as immune checkpoints and immunosuppressive molecules. Therefore, targeting TME and remodeling immunity in cold tumors can improve the chance of tumor repression after therapy. However, tumor stroma prevents the infiltration of inflammatory cells and hinders the penetration of diverse molecules and drugs. Nanoparticles are an intriguing tool for the delivery of immune modulatory agents and shifting cold to hot tumors. In this review article, we discuss the mechanisms underlying the ability of nanoparticles loaded with different drugs and products to modulate TME and enhance immune cell infiltration. We also focus on newest progresses in the design and development of nanoparticle-based strategies for changing cold to hot tumors. These include the use of nanoparticles for targeted delivery of immunomodulatory agents, such as cytokines, small molecules, and checkpoint inhibitors, and for co-delivery of chemotherapy drugs and immunomodulatory agents. Furthermore, we discuss the potential of nanoparticles for enhancing the efficacy of cancer vaccines and cell therapy for overcoming resistance to treatment.

Lipid- and Polymer-Based Nanocarrier Platforms for Cancer Vaccine Delivery

Cancer immunotherapy has gained popularity in recent years in the search for effective treatment modalities for various malignancies, particularly those that are resistant to conventional chemo- and radiation therapy. Cancer vaccines target the cancer-immunity cycle by boosting the patient's own immune system to recognize and kill cancer cells, thus serving as both preventative and curative therapeutic tools. Among the different types of cancer vaccines, those based on nanotechnology have shown great promise in advancing the field of cancer immunotherapy. Lipid-based nanoparticles (NPs) have become the most advanced platforms for cancer vaccine delivery, but polymer-based NPs have also received considerable interest. This Review aims to provide an overview of the nanotechnology-enabled cancer vaccine landscape, focusing on recent advances in lipid- and polymer-based nanovaccines and their hybrid structures and discussing the challenges against the clinical translation of these important nanomedicines.

PEGylated Tween 80-functionalized chitosan-lipidic nano-vesicular hybrids for heightening nose-to-brain delivery and bioavailability of metoclopramide

A PEGylated Tween 80-functionalized chitosan-lipidic (PEG-T-Chito-Lip) nano-vesicular hybrid was developed for intranasal administration as an alternative delivery route to help improve the poor oral bioavailability of BCS class-III model/antiemetic (metoclopramide hydrochloride; MTC). The influence of varying levels of chitosan, cholesterol, PEG 600, and Tween 80 on the stability/release parameters of the formulated nanovesicles was optimized using Draper-Lin Design. Two optimized formulations (Opti-Max and Opti-Min) with both maximized and minimized MTC-release goals, were predicted, characterized, and proved their vesicular outline via light/electron microscopy, along with the mutual prompt/extended in-vitro release patterns. The dual-optimized MTC-loaded PEG-T-Chito-Lip nanovesicles were loaded in intranasal in-situ gel (ISG) and further underwent in-vivo pharmacokinetics/nose-to-brain delivery valuation on Sprague-Dawley rats. The absorption profiles in plasma (plasma-AUC_0-∞) of the intranasal dual-optimized MTC-loaded nano-vesicular ISG formulation in pretreated rats were 2.95-fold and 1.64-fold more than rats pretreated with orally administered MTC and intranasally administered raw MTC-loaded ISG formulation, respectively. Interestingly, the brain-AUC_0-∞ of the intranasal dual-optimized MTC-loaded ISG was 10 and 3 times more than brain-AUC_0-∞ of the MTC-oral tablet and the intranasal raw MTC-loaded ISG, respectively. It was also revealed that the intranasal dual-optimized ISG significantly had the lowest liver-AUC_0-∞ (862.19 ng.g^-1.h^-1) versus the MTC-oral tablet (5732.17 ng.g^-1.h^-1) and the intranasal raw MTC-loaded ISG (1799.69 ng.g^-1.h^-1). The brain/blood ratio profile for the intranasal dual-optimized ISG was significantly enhanced over all other MTC formulations (P < 0.05). Moreover, the 198.55% drug targeting efficiency, 75.26% nose-to-brain direct transport percentage, and 4.06 drug targeting index of the dual-optimized formulation were significantly higher than those of the raw MTC-loaded ISG formulation. The performance of the dual-optimized PEG-T-Chito-Lip nano-vesicular hybrids for intranasal administration evidenced MTC-improved bioavailability, circumvented hepatic metabolism, and enhanced brain targetability, with increased potentiality in heightening the convenience and compliance for patients.

Nanoimmunoengineering strategies in cancer diagnosis and therapy

Cancer immunotherapy strategies in combination with engineered nanosystems have yielded beneficial results in the treatment of cancer and their application is increasing day by day. The pivotal role of stimuli-responsive nanosystems and nanomedicine-based cancer immunotherapy, as a subsidiary discipline in the field of immunology, cannot be ignored. Today, rapid advances in nanomedicine are used as a platform for exploring new therapeutic applications and modern smart healthcare management strategies. The progress of nanomedicine in cancer treatment has confirmed the findings of immunotherapy in the medical research phase. This study concentrates on approaches connected to the efficacy of nanoimmunoengineering strategies for cancer immunotherapies and their applications. By assessing improved approaches, different aspects of the nanoimmunoengineering strategies for cancer therapies are discussed in this study.

Design of Polymeric Carriers for Intracellular Peptide Delivery in Oncology Applications

In recent decades, peptides, which can possess high potency, excellent selectivity, and low toxicity, have emerged as promising therapeutics for cancer applications. Combined with an improved understanding of tumor biology and immuno-oncology, peptides have demonstrated robust antitumor efficacy in preclinical tumor models. However, the translation of peptides with intracellular targets into clinical therapies has been severely hindered by limitations in their intrinsic structure, such as low systemic stability, rapid clearance, and poor membrane permeability, that impede intracellular delivery. In this Review, we summarize recent advances in polymer-mediated intracellular delivery of peptides for cancer therapy, including both therapeutic peptides and peptide antigens. We highlight strategies to engineer polymeric materials to increase peptide delivery efficiency, especially cytosolic delivery, which plays a crucial role in potentiating peptide-based therapies. Finally, we discuss future opportunities for peptides in cancer treatment, with an emphasis on the design of polymer nanocarriers for optimized peptide delivery.

Design, optimization, and in-vivo hypoglycaemic effect of nanosized glibenclamide for inhalation delivery

The aim of this research was the development and optimization of nanoniosomes for delivery of glibenclamide (Gbn) as hypoglycaemic agent to the lung in an inhaler dosage form. Fifteen formulae of niosomal dispersions were prepared according to Box-Behnken design. The effect of drug amount, Cholesterol molar ratio, and Hydrophilic lipophilic balance (HLB) values of the surfactant on the mean vesicle size, Zeta potential (ZP), polydispersity index (PDI), entrapment efficiency, and in-vitro released of Gbn were investigated. A quality control check was performed on an inhaler filled with the optimum nanoniosomal formula. The in-vivo hypoglycaemic effect of nanoniosomal inhalation was also evaluated. The vesicle size observed of the optimized formula was 172 ± 4.6 nm, PDI was 0.304 ± 0.06 and ZP was -49.9 ± 1.5 mv with 69 ± 9.3% in-vitro drug release after 2 h. The Cholesterol molar ratio and the HLB value showed a statistically significant effect on dependent variables. In-vivo results proved that nanoniosomes were efficiently delivered from the inhalation canister showing a mass median aerodynamic diameter of 1.4 micron. The inhaled nanoniosomal dispersion loaded with Gbn showed a decrease in blood glucose level of hyperglycaemic rats by 51.42 ± 5.2%± after 180 min which was nearly two folds compared to oral Gbn. Gibenclamide nanoniosomes inhaler could be suggested as a novel effective dosage form for the treatment of Diabetes mellitus.

Recent Advances in Cell Membrane-Derived Biomimetic Nanotechnology for Cancer Immunotherapy

Immunotherapy will significantly impact the standard of care in cancer treatment. Recent advances in nanotechnology can improve the efficacy of cancer immunotherapy. However, concerns regarding efficiency of cancer nanomedicine, complex tumor microenvironment, patient heterogeneity, and systemic immunotoxicity drive interest in more novel approaches to be developed. For this purpose, biomimetic nanoparticles are developed to make innovative changes in the delivery and biodistribution of immunotherapeutics. Biomimetic nanoparticles have several advantages that can advance the clinical efficacy of cancer immunotherapy. Thus there is a greater push toward the utilization of biomimetic nanotechnology for developing effective cancer immunotherapeutics that demonstrate increased specificity and potency. The recent works and state-of-the-art strategies for anti-tumor immunotherapeutics are highlighted here, and particular emphasis has been given to the applications of cell-derived biomimetic nanotechnology for cancer immunotherapy.

Fluticasone propionate-loaded solid lipid nanoparticles with augmented anti-inflammatory activity: optimisation, characterisation and pharmacodynamic evaluation on rats

This work aimed to elaborate an optimised fluticasone propionate (FP)-loaded solid lipid nanoparticles (SLNs) to enhance FP effectiveness for topical inflammatory remediation. The influences of drug amount, lipid, and surfactant ratios, on drug release pattern and stability were investigated utilising Box-Behnken design. Elaboration, characterisation, and pharmacodynamic evaluation in comparison with the marketed formulation (Cutivate® cream, 0.05%w/w FP), were conducted for the optimised SLNs. The optimised SLNs with a size of 248.3 ± 1.89 nm (PDI = 0.275) and -32.4 ± 2.85 mV zeta potential were evidenced good stability physiognomies. The optimised SLNs pre-treated rats exhibited non-significant difference in paw volume from that of the control group and showed a significant reduction in both PGE₂ and TNF-α levels by 51.5 and 61%, respectively, in comparison with the Carrageenan group. The optimised FP-loaded SLNs maximised the efficacy of FP towards inflammation alleviation that increase its potential as efficient implement in inflammatory skin diseases remediation.

Glycyrrhizic acid promotes neural repair by directly driving functional remyelination

Natural compounds are a rich source of effective candidate drugs for the treatment of neurological disorders. Glycyrrhizic acid (GA), the major water-soluble ingredient isolated from Glycyrrhiza glabra, is reported to show anti-inflammatory and immunomodulatory activities. However, its effect on CNS demyelinating disease is unclear. In this study, we showed that GA ameliorated the clinical disease severity of experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS), especially at the chronic stage of clinical EAE. Histological evaluation demonstrated that, in the prophylactic treatment regimen, GA significantly inhibited inflammatory demyelination in the CNS. During the chronic stage when myelin and axon damage has already occurred, GA induced oligodendrocyte progenitor cell (OPC) differentiation into mature oligodendrocytes, thus effectively accelerating remyelination. Evidence from the cuprizone-induced mouse model of de- and remyelination, ex vivo organotypic slice cultures, and in vitro OPC maturation experiments indicated that the observed efficacy of this compound resulted directly from enhanced remyelination rather than immune suppression. Furthermore, we found that GA promoted oligodendrocyte maturation through modulating GSK-3β signaling pathways. Our data led to the conclusion that GA could be used as a potential therapeutic candidate for the treatment of demyelinating diseases such as MS, which remains refractory to available treatments.

A new formulation of hydrophobin-coated niosome as a drug carrier to cancer cells

Hydrophobin-1 (HFB-1) found on the surface of fungal spores, plays a role in the lack of antigen recognition by the host immune system. The present study aimed to evaluate the potential application of HFB-1 for the delivery of doxorubicin (Dox) into different cell lines. Coating the surface of niosomes (Nio) with HFB-1 leads to the hypothesis that this protein can confer protection against in vivo immune-system recognition and prevent the immune response. Thus, HFB-1 could become a promising alternative to polyethylene glycol (PEG). Here, HFB-1-coated niosome loaded with doxorubicin (Dox) based on Span 40, Tween 40 and cholesterol was prepared and compared with the PEG-coated niosome. Physicochemical characteristics of the prepared formulations in terms of size, zeta potential, polydispersity index (PDI), morphology, entrapment efficiency (EE), and release rate were evaluated at different pH levels (2, 5.2, and 7.4). In the end, the in vitro cytotoxicity assay was performed on four different cancer cell lines namely A549, MDA-MB-231, C6 and PC12 in addition to one control cell line (3 T3) to ensure the formulation's selectivity against cancer cells. Results showed that the niosomes coated with HFB-1 presented better size distribution, higher EE, more sustained release profile, enhanced biocompatibility and improved anticancer effects as compared to the PEG-coated niosomes. Interestingly, the viability percentage of the control cell line was higher than different cancer cells when treated with the formulations, which indicates the higher selectivity of the formulation against cancer cells. In conclusion, loading the niosomes with Dox and coating them with HFB-1 enhanced their efficacy and selectivity toward cancer cells, presenting a promising drug delivery system for sustained drug release in cancer treatment.

Nanodermatology-based solutions for psoriasis: State-of-the art and future prospects

Nanodermatology is an emerging, multidisciplinary science, arising from the convergence of nanotechnology, pharmacology, physics/biophysics, chemistry/biochemistry, chemical engineering, material science, and clinical medicine. Nanodermatology deals with (a) skin biology, anatomy, and physiology at the nanoscale ("skin nanobiology"), (b) diagnosis performed by means of novel diagnostic devices, assisted by nanobiotechnologies ("nanodiagnosis"), and (c) treatment through innovative therapeutic agents, including phototherapy ("photonanotherapy"/"photonanodermatology") and systemic/topical drug administration ("nanotherapy") at the nanoscale, and drug delivery-such as transdermal or dermal drug delivery (TDDD/DDD)-enhanced and improved by nanostructures and nanodrugs ("nanodrug delivery"). Nanodermatology, as a super-specialized branch of dermatology, is a quite recent specialty: the "Nanodermatology Society" founded by the eminent dermatologist Dr. Adnan Nasir, was established in 2010, with the aim of bringing together different stakeholders, including dermatologists, nanotechnology scientists, policy-makers and regulators, as well as students and medical residents. Psoriasis has a prevalence of 2-3% worldwide and imposes a severe clinical and societal burden. Nanodermatology-based solutions appear promising for the proper treatment and management of psoriasis, assisting and enhancing different steps of the process of health-care delivery: from the diagnosis to the therapeutics, paving the way for a personalized approach, based on the specific dysregulated biomarkers.

Targeted co-delivery of Trp-2 polypeptide and monophosphoryl lipid A by pH-sensitive poly (β-amino ester) nano-vaccines for melanoma

Dendritic cell (DC)-targeted vaccines based on nanotechnology are a promising strategy to efficiently induce potent immune responses. We synthesized and manufactured a mannose-modified poly (β-amino ester) (PBAE) nano-vaccines with easily tuneable and pH-sensitive characteristics to co-deliver the tumor-associated antigen polypeptide Trp-2 and the TLR4 agonist monophosphoryl lipid A (MPLA). To reduce immunosuppression in the tumor microenvironment, an immune checkpoint inhibitor, PD-L1 antagonist, was administrated along with PBAE nano-vaccines to delay melanoma development. We found that mannosylated Trp-2 and MPLA-loaded PBAE nano-vaccines can target and mature DCs, consequently boosting antigen-specific cytotoxic T lymphocyte activity against melanoma. The prophylactic study indicates that combination therapy with PD-L1 antagonist further enhanced anti-tumor efficacy by 3.7-fold and prolonged median survival time by 1.6-fold more than free Trp-2/MPLA inoculation. DC-targeting PBAE polymers have a great potential as a nanotechnology platform to design vaccines and achieve synergistic anti-tumor effects with immune checkpoint therapy.

Nanovaccines for cancer immunotherapy

The past few decades have witnessed the booming field of cancer immunotherapy. Cancer therapeutic vaccines, either alone or in combination with other immunotherapies such as adoptive cell therapy or immune checkpoint blockade therapy, are an attractive class of cancer immunotherapeutics. However, cancer vaccines have thus far shown suboptimal efficacy in the clinic. Nanomedicines offer unique opportunities to improve the efficacy of these vaccines. A variety of nanoplatforms have been investigated to deliver molecular or cellular or subcellular vaccines to target lymphoid tissues and cells, thereby promoting the potency and durability of anti-tumor immunity while reducing adverse side effects. In this article, we reviewed the key parameters and features of nanovaccines for cancer immunotherapy; we highlighted recent advances in the development of cancer nanovaccines based on synthetic nanocarriers, biogenic nanocarriers, as well as semi-biogenic nanocarriers; and we summarized newly emerging types of nanovaccines, such as those based on stimulator of interferon genes agonists, cancer neoantigens, mRNA vaccines, as well as artificial antigen-presenting cells. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Decoration of Nanovesicles with pH (Low) Insertion Peptide (pHLIP) for Targeted Delivery

Acidity at surface of cancer cells is a hallmark of tumor microenvironments, which does not depend on tumor perfusion, thus it may serve as a general biomarker for targeting tumor cells. We used the pH (low) insertion peptide (pHLIP) for decoration of liposomes and niosomes. pHLIP senses pH at the surface of cancer cells and inserts into the membrane of targeted cells, and brings nanomaterial to close proximity of cellular membrane. DMPC liposomes and Tween 20 or Span 20 niosomes with and without pHLIP in their coating were fully characterized in order to obtain fundamental understanding on nanocarrier features and facilitate the rational design of acidity sensitive nanovectors. The samples stability over time and in presence of serum was demonstrated. The size, ζ-potential, and morphology of nanovectors, as well as their ability to entrap a hydrophilic probe and modulate its release were investigated. pHLIP decorated vesicles could be useful to obtain a prolonged (modified) release of biological active substances for targeting tumors and other acidic diseased tissues.

Barata T, Gaspar M, Brocchini S, Zloh M, Peppas NA, Satchi-Fainaro R, F. Florindo H. α-Galactosylceramide and peptide-based nano-vaccine synergistically induced a strong tumor suppressive effect in melanoma

α-Galactosylceramide (GalCer) is a glycolipid widely known as an activator of Natural killer T (NKT) cells, constituting a promising adjuvant against cancer, including melanoma. However, limited clinical outcomes have been obtained so far. This study evaluated the synergy between GalCer and major histocompatibility complex (MHC) class I and MHC class II melanoma-associated peptide antigens and the Toll-Like Receptor (TLR) ligands CpG and monophosphoryl lipid A (MPLA), which we intended to maximize following their co-delivery by a nanoparticle (NP). This is expected to improve GalCer capture by dendritic cells (DCs) and subsequent presentation to NKT cells, simultaneously inducing an anti-tumor specific T-cell mediated immunity. The combination of GalCer with melanoma peptides and TLR ligands successfully restrained tumor growth. The tumor volume in these animals was 5-fold lower than the ones presented by mice immunized with NPs not containing GalCer. However, tumor growth was controlled at similar levels by GalCer entrapped or in its soluble form, when mixed with antigens and TLR ligands. Those two groups showed an improved infiltration of T lymphocytes into the tumor, but only GalCer-loaded nano-vaccine induced a prominent and enhanced infiltration of NKT and NK cells. In addition, splenocytes of these animals secreted levels of IFN-γ and IL-4 at least 1.5-fold and 2-fold higher, respectively, than those treated with the mixture of antigens and adjuvants in solution. Overall, the combined delivery of the NKT agonist with TLR ligands and melanoma antigens via this multivalent nano-vaccine displayed a synergistic anti-tumor immune-mediated efficacy in B16F10 melanoma mouse model.

STATEMENT OF SIGNIFICANCE

Combination of α-galactosylceramide (GalCer), a Natural Killer T (NKT) cell agonist, with melanoma-associated antigens presented by MHC class I (Melan-A:26) and MHC class II (gp100:44) molecules, and Toll-like Receptor (TLR) ligands (MPLA and CpG), within nanoparticle matrix induced a prominent anti-tumor immune response able to restrict melanoma growth. An enhanced infiltration of NKT and NK cells into tumor site was only achieved when the combination GalCer, antigens and TLR ligands were co-delivered by the nanovaccine.

Lawsone-loaded Niosome and its antitumor activity in MCF-7 breast Cancer cell line: a Nano-herbal treatment for Cancer

Phytochemicals like Lawsone have some drawbacks that stem from their poor solubility. Low solubility in aqueous mediums results in low bioavailability, poor permeability and instability of phytochemical compounds in biological environments. The aim of this study was to design nanoniosomes containing Lawsone (Law) using non-ionic surfactants and cholesterol. Niosomes were prepared by thin film hydration method (TFH). Then, they were loaded with Henna extract (HLaw) and standard Lawsone (SLaw), and two resulted formulations were compared. The henna extract was analyzed by mass gas chromatography. Size, zeta potential, polydispersity index (PDI) and morphology of the loaded formulations were evaluated by dynamic light scattering (DLS) and scanning electron spectroscopy (SEM). The incorporation and release rate of Law from niosome bilayers were evaluated by UV-Vis spectroscopy. In vitro experiments were carried out to evaluate antitumor activity in MCF-7 cell line. The results showed distinct spherical shapes and particle sizes were about 250 nm in diameter and have negative zeta potentials. Niosomes were stable at 4 °C for 2 months. Entrapment efficiently of both formulations was about 70% and showed a sustained release profile. In vitro study exhibited that using of niosome to encapsulating Law can significantly increase antitumor activity of formulation in MCF-7 cell line compared to Law solution (free Law). Thus, niosomes are a promising carrier system for delivery of phytochemical compounds that have poor solubility in biological fluids. Graphical abstract ᅟ.

Design and Development of Biomimetic Nanovesicles Using a Microfluidic Approach

The advancement of nanotechnology toward more sophisticated bioinspired approaches has highlighted the gap between the advantages of biomimetic and biohybrid platforms and the availability of manufacturing processes to scale up their production. Though the advantages of transferring biological features from cells to synthetic nanoparticles for drug delivery purposes have recently been reported, a standardizable, batch-to-batch consistent, scalable, and high-throughput assembly method is required to further develop these platforms. Microfluidics has offered a robust tool for the controlled synthesis of nanoparticles in a versatile and reproducible approach. In this study, the incorporation of membrane proteins within the bilayer of biomimetic nanovesicles (leukosomes) using a microfluidic-based platform is demonstrated. The physical, pharmaceutical, and biological properties of microfluidic-formulated leukosomes (called NA-Leuko) are characterized. NA-Leuko show extended shelf life and retention of the biological functions of donor cells (i.e., macrophage avoidance and targeting of inflamed vasculature). The NA approach represents a universal, versatile, robust, and scalable tool, which is extensively used for the assembly of lipid nanoparticles and adapted here for the manufacturing of biomimetic nanovesicles.

Co-delivery of human cancer-testis antigens with adjuvant in protein nanoparticles induces higher cell-mediated immune responses

Nanoparticles have attracted considerable interest as cancer vaccine delivery vehicles for inducing sufficient CD8⁺ T cell-mediated immune responses to overcome the low immunogenicity of the tumor microenvironment. Our studies described here are the first to examine the effects of clinically-tested human cancer-testis (CT) peptide epitopes within a synthetic nanoparticle. Specifically, we focused on two significant clinical CT targets, the HLA-A2 restricted epitopes of NY-ESO-1 and MAGE-A3, using a viral-mimetic packaging strategy. Our data shows that simultaneous delivery of a NY-ESO-1 epitope (SLLMWITQV) and CpG using the E2 subunit assembly of pyruvate dehydrogenase (E2 nanoparticle), resulted in a 25-fold increase in specific IFN-γ secretion in HLA-A2 transgenic mice. This translated to a 15-fold increase in lytic activity toward target cancer cells expressing the antigen. Immunization with a MAGE-A3 epitope (FLWGPRALV) delivered with CpG in E2 nanoparticles yielded an increase in specific IFN-γ secretion and cell lysis by 6-fold and 9-fold, respectively. Furthermore, combined delivery of NY-ESO-1 and MAGE-A3 antigens in E2 nanoparticles yielded an additive effect that increased lytic activity towards cells bearing NY-ESO-1⁺ and MAGE-A3⁺. Our investigations demonstrate that formulation of CT antigens within a nanoparticle can significantly enhance antigen-specific cell-mediated responses, and the combination of the two antigens in a vaccine can preserve the increased individual responses that are observed for each antigen alone.

Encapsulation of Hydrophilic and Hydrophobic Peptides into Hollow Mesoporous Silica Nanoparticles for Enhancement of Antitumor Immune Response

Codelivery of combinational antigenic peptides and adjuvant to antigen presenting cells is expected to amplify tumor specific T lymphocytes immune responses while minimizing the possibility of tumor escaping and reducing immune tolerance to single antigenic peptide. However, the varied hydrophobicities of these multivariant derived short antigenic peptides limit their codelivery efficiency in conventional delivery systems. Here, a facile yet effective route is presented to generate monodisperse and stable hollow mesoporous silica nanoparticles (HMSNs) for codelivering of HGP100_25-33 and TRP2_180-188 , two melanoma-derived peptides with varied hydrophobicities. The HMSNs with large pore size can improve the encapsulation efficiency of both HGP100 and TRP2 after NH₂ modification on the inner hollow core and COOH modification in the porous channels. HGP100 and TRP2 loaded HMSNs (HT@HMSNs) are further enveloped within monophosphoryl lipid A adjuvant entrapped lipid bilayer (HTM@HMLBs), for improved stability/biocompatibility and codelivery efficiency of multiple peptides, adjuvant, and enhanced antitumor immune responses. HTM@HMLBs increase uptake by dendritic cells (DCs) and stimulate DCs maturation efficiently, which further induce the activation of both tumor specific CD8⁺ and CD4⁺ T lymphocytes. Moreover, HTM@HMLBs can significantly inhibit tumor growth and lung metastasis in murine melanoma models with good safety profiles. HMSNs enveloped with lipid bilayers (HMLBs) are believed to be a promising platform for codelivery of multiple peptides, adjuvant, and enhancement of antitumor efficacy of conventional vaccinations.

Nanoparticle-based strategies for cancer immunotherapy and immunodiagnostics

Although recent successes in clinical trials are strengthening research focused on cancer immunology, the poor immunogenicity and off-target side effects of immunotherapeutics remain major challenges in translating these promising approaches to clinically feasible therapies in the treatment of a large range of tumors. Nanotechnology offers target-based approaches, which have shown significant improvements in the rapidly advancing field of cancer immunotherapy. Here, we first discuss the chemical and physical features of nanoparticulate systems that can be tuned to address the anticancer immune response, and then review recent, key examples of the exploited strategies, ranging from nanovaccines to NPs revising the tumor immunosuppressive microenvironment, up to immunotherapeutic multimodal NPs. Finally, the paper concludes by identifying the promising and outstanding challenges the field of emerging nanotechnologies is facing for cancer immunotherapy.

Nanotechnology based therapeutic modality to boost anti-tumor immunity and collapse tumor defense

Cancer is still the leading cause of death. While traditional treatments such as surgery, chemotherapy and radiotherapy play dominating roles, recent breakthroughs in cancer immunotherapy indicate that the influence of immune system on cancer development is virtually beyond our expectation. Manipulating the immune system to fight against cancer has been thriving in recent years. Further understanding of tumor anatomy provides opportunities to put a brake on immunosuppression by overcoming tumor intrinsic resistance or modulating tumor microenvironment. Nanotechnology which provides versatile engineered approaches to enhance therapeutic effects may potentially contribute to the development of future cancer treatment modality. In this review, we will focus on the application of nanotechnology both in boosting anti-tumor immunity and collapsing tumor defense.

pH-sensitive niosomes: Effects on cytotoxicity and on inflammation and pain in murine models

pH-sensitive nonionic surfactant vesicles (niosomes) by polysorbate-20 (Tween-20) or polysorbate-20 derivatized by glycine (added as pH sensitive agent), were developed to deliver Ibuprofen (IBU) and Lidocaine (LID). For the physical-chemical characterization of vesicles (mean size, size distribution, zeta potential, vesicle morphology, bilayer properties and stability) dynamic light scattering (DLS), small angle X-ray scattering and fluorescence studies were performed. Potential cytotoxicity was evaluated on immortalized human keratinocyte cells (HaCaT) and on immortalized mouse fibroblasts Balb/3T3. In vivo antinociceptive activity (formalin test) and anti-inflammatory activity tests (paw edema induced by zymosan) in murine models were performed on drug-loaded niosomes. pH-sensitive niosomes were stable in the presence of 0 and 10% fetal bovine serum, non-cytotoxic and able to modify IBU or LID pharmacological activity in vivo. The synthesis of stimuli responsive surfactant, as an alternative to add pH-sensitive molecules to niosomes, could represent a promising delivery strategy for anesthetic and anti-inflammatory drugs.

Immunological Principles Guiding the Rational Design of Particles for Vaccine Delivery

Despite the immense public health successes of immunization over the past century, effective vaccines are still lacking for globally important pathogens such as human immunodeficiency virus, malaria, and tuberculosis. Exciting recent advances in immunology and biotechnology over the past few decades have facilitated a shift from empirical to rational vaccine design, opening possibilities for improved vaccines. Some of the most important advancements include (i) the purification of subunit antigens with high safety profiles, (ii) the identification of innate pattern recognition receptors (PRRs) and cognate agonists responsible for inducing immune responses, and (iii) developments in nano- and microparticle fabrication and characterization techniques. Advances in particle engineering now allow highly tunable physicochemical properties of particle-based vaccines, including composition, size, shape, surface characteristics, and degradability. Enhanced collaborative efforts between researchers in immunology and materials science are expected to rise to next-generation vaccines. This process will be significantly aided by a greater understanding of the immunological principles guiding vaccine antigenicity, immunogenicity, and efficacy. With specific emphasis on PRR-targeted adjuvants and particle physicochemical properties, this review aims to provide an overview of the current literature to guide and focus rational particle-based vaccine design efforts.

Nanoparticle-Based Manipulation of Antigen-Presenting Cells for Cancer Immunotherapy

Immunotherapeutic approaches for treating cancer overall have been receiving a considerable amount of interest due to the recent approval of several clinical formulations. Among the different modalities, anticancer vaccination acts by training the body to endogenously generate a response against tumor cells. However, despite the large amount of work that has gone into the development of such vaccines, the near absence of clinically approved formulations highlights the many challenges facing those working in the field. The generation of potent endogenous anticancer responses poses unique challenges due to the similarity between cancer cells and normal, healthy cells. As researchers continue to tackle the limited efficacy of vaccine formulations, fresh and novel approaches are being sought after to address many of the underlying problems. Here the application of nanoparticle technology towards the development of anticancer vaccines is discussed. Specifically, there is a focus on the benefits of using such strategies to manipulate antigen presenting cells (APCs), which are essential to the vaccination process, and how nanoparticle-based platforms can be rationally engineered to elicit appropriate downstream immune responses.

Erythrocyte Membrane-Enveloped Polymeric Nanoparticles as Nanovaccine for Induction of Antitumor Immunity against Melanoma

Cancer immunotherapy is mainly focused on manipulating patient's own immune system to recognize and destroy cancer cells. Vaccine formulations based on nanotechnology have been developed to target delivery antigens to antigen presenting cells (APCs), especially dendritic cells (DCs) for efficiently induction of antigen-specific T cells response. To enhance DC targeting and antigen presenting efficiency, we developed erythrocyte membrane-enveloped poly(d,l-lactide-co-glycolide) (PLGA) nanoparticles for antigenic peptide (hgp10025-33) and toll-like receptor 4 agonist, monophosphoryl lipid (MPLA). A Mannose-inserted membrane structure was constructed to actively target APCs in the lymphatic organ, and redox-sensitive peptide-conjugated PLGA nanoparticles were fabricated which prone to cleave in the intracellular milieu. The nanovaccine demonstrated the retained protein content in erythrocyte and enhanced in vitro cell uptake. An antigen-depot effect was observed in the administration site with promoted retention in draining lymph nodes. Compared with other formulations after intradermal injection, the nanovaccine prolonged tumor-occurring time, inhibited tumor growth, and suppressed tumor metastasis in prophylactic, therapeutic, and metastatic melanoma models, respectively. Additionally, we revealed that nanovaccine effectively enhanced IFN-γ secretion and CD8(+) T cell response. Taken together, these results demonstrated the great potential in applying an erythrocyte membrane-enveloped polymeric nanoplatform for an antigen delivery system in cancer immunotherapy.

Recent advances in peptide-based subunit nanovaccines

Vaccination is the most efficient way to protect humans against pathogens. Peptide-based vaccines offer several advantages over classical vaccines, which utilized whole organisms or proteins. However, peptides alone are not immunogenic and need a delivery system that can boost their recognition by the immune system. In recent years, nanotechnology-based approaches have become one of the most promising strategies in peptide vaccine delivery. This review summarizes knowledge on peptide vaccines and nanotechnology-based approaches for their delivery. The recently reported nano-sized delivery platforms for peptide antigens are reviewed, including nanoparticles composed of polymers, peptides, lipids, inorganic materials and nanotubes. The future prospects for peptide-based nanovaccines are discussed.

Gel-embedded niosomes: preparation, characterization and release studies of a new system for topical drug delivery

In the present paper physical gels, prepared with two polysaccharides, Xanthan and Locust Bean Gum, and loaded with non-ionic surfactant vesicles, are described. The vesicles, composed by Tween20 and cholesterol or by Tween85 and Span20, were loaded with Monoammonium glycyrrhizinate for release experiments. Size and zeta (ζ)-potential of the vesicles were evaluated and the new systems were characterized by rheological and dynamo-mechanical measurements. For an appropriate comparison, a Carbopol gel and a commercial gel for topical applications were also tested. The new formulations showed mechanical properties comparable with those of the commercial product indicating their suitability for topical applications. In vitro release experiments showed that the polysaccharide network protects the integrity of the vesicles and leads to their slow release without disruption of the aggregated structures. Furthermore, being the vesicles composed of molecules possessing enhancing properties, the permeation of the loaded drugs topically delivered can be improved. Thus, the new systems combine the advantages of matrices for a modified release (polymeric component) and those of an easier permeability across the skin (vesicle components). Finally, shelf live experiments indicated that the tested gel/vesicle formulations were stable over 1 year with no need of preservatives.

Poly(sebacic anhydride) nanocapsules as carriers: effects of preparation parameters on properties and release of doxorubicin

Poly(sebacic anhydride) (PSA) is a promising polymer for the production of drug delivery vehicles. The aim of this work is to study the effect of preparation parameters on the quality of the nanoparticles. In this study, doxorubicin (DOX)-loaded PSA nanocapsules were prepared by an emulsion method. Effects of factors such as type of organic solvent, co-solute (surfactant) and its concentration on drug-loading efficiency, particle size and size distribution, morphology and release profile were examined to gain insight in the preparation and stability of nanostructures. Particles with sizes in the range of 218-1198 nm were prepared. The smallest particles with a narrow size distribution were prepared by using polyvinyl alcohol as a co-solute and dichloromethane as a solvent. Efficiency and intracellular release of doxorubicin from the formulated particles were studied on MDA-MB-231 cells. It was observed that DOX-loaded PSA particles can diffuse into the cells and intracellular antitumour activity is directly related to the released amount of drug from the PSA nanocapsules.

Biomaterials for nanoparticle vaccine delivery systems

Subunit vaccination benefits from improved safety over attenuated or inactivated vaccines, but their limited capability to elicit long-lasting, concerted cellular and humoral immune responses is a major challenge. Recent studies have demonstrated that antigen delivery via nanoparticle formulations can significantly improve immunogenicity of vaccines due to either intrinsic immunostimulatory properties of the materials or by co-entrapment of molecular adjuvants such as Toll-like receptor agonists. These studies have collectively shown that nanoparticles designed to mimic biophysical and biochemical cues of pathogens offer new exciting opportunities to enhance activation of innate immunity and elicit potent cellular and humoral immune responses with minimal cytotoxicity. In this review, we present key research advances that were made within the last 5 years in the field of nanoparticle vaccine delivery systems. In particular, we focus on the impact of biomaterials composition, size, and surface charge of nanoparticles on modulation of particle biodistribution, delivery of antigens and immunostimulatory molecules, trafficking and targeting of antigen presenting cells, and overall immune responses in systemic and mucosal tissues. This review describes recent progresses in the design of nanoparticle vaccine delivery carriers, including liposomes, lipid-based particles, micelles and nanostructures composed of natural or synthetic polymers, and lipid-polymer hybrid nanoparticles.