Size-Dependent Phagocytic Uptake and Immunogenicity of Gliadin Nanoparticles

PLGA-LEC/F127 hybrid nanoparticles loaded with curcumin and their modulatory effect on monocytes

Aim: To investigate the effect of surfactant type on curcumin-loaded (CUR) PLGA nanoparticles (NPs) to modulate monocyte functions. Materials & methods: The nanoprecipitation method was used, and PLGA NPs were designed using Pluronic F127 (F127) and/or lecithin (LEC) as surfactants. Results: The Z-average of the NPs was <200 nm, they had a spherical shape, Derjaguin-Muller-Toporov modulus >0.128 MPa, they were stable during storage at 4°C, ζ-potential ∼-40 mV, polydispersity index <0.26 and % EE of CUR >94%. PLGA-LEC/F127 NPs showed favorable physicochemical and nanomechanical properties. These NPs were bound and internalized mainly by monocytes, suppressed monocyte-induced reactive oxygen species production, and decreased the ability of monocytes to modulate T-cell proliferation. Conclusion: These results demonstrate the potential of these NPs for targeted therapy.

Strategies for the development of metalloimmunotherapies

Metal ions play crucial roles in the regulation of immune pathways. In fact, metallodrugs have a long record of accomplishment as effective treatments for a wide range of diseases. Here we argue that the modulation of interactions of metal ions with molecules and cells involved in the immune system forms the basis of a new class of immunotherapies. By examining how metal ions modulate the innate and adaptive immune systems, as well as host-microbiota interactions, we discuss strategies for the development of such metalloimmunotherapies for the treatment of cancer and other immune-related diseases.

Beyond the Charge: Interplay of Nanogels' Functional Group and Zeta-Potential for Antifungal Drug Delivery to Human Pathogenic Fungus Aspergillus Fumigatus

The ubiquitous mold Aspergillus fumigatus (A. fumigatus) is one of the main fungal pathogens causing invasive infections in immunocompromised humans. Conventional antifungal agents exhibit limited efficacy and often cause severe side effects. Nanoparticle-based antifungal delivery provides a promising alternative, which can increase local drug concentration; while, mitigating toxicity, thereby enhancing treatment efficacy. Previous research underscores the potential of poly(glycidol)-based nanogels (NG) with negative surface charge as carriers for delivering antifungals to A. fumigatus hyphae. In this study, NG is tailored with 2-carboxyethyl acrylate (CEA) or with phosphoric acid 2-hydroxyethyl acrylate (PHA). It is discovered that quenching with PHA clearly improves the adhesion of NG to hyphal surface and the internalization of NG into the hyphae under protein-rich conditions, surpassing the outcomes of non-quenched and CEA-quenched NG. This enhancement cannot be solely attributed to an increase in negative surface charge but appears to be contingent on the functional group of the quencher. Further, it is demonstrated that itraconazole-loaded, PHA-functionalized nanogels (NGxPHA-ITZ) show lower MIC in vitro and superior therapeutic effect in vivo against A. fumigatus compared to pure itraconazole. This confirms NGxPHA as a promising antifungal delivery system.

Macrophages as carriers of boron carbide nanoparticles dedicated to boron neutron capture therapy

BACKGROUND

The use of cells as carriers for the delivery of nanoparticles is a promising approach in anticancer therapy, mainly due to their natural properties, such as biocompatibility and non-immunogenicity. Cellular carriers prevent the rapid degradation of nanoparticles, improve their distribution, reduce cytotoxicity and ensure selective delivery to the tumor microenvironment. Therefore, we propose the use of phagocytic cells as boron carbide nanoparticle carriers for boron delivery to the tumor microenvironment in boron neutron capture therapy.

RESULTS

Macrophages originating from cell lines and bone marrow showed a greater ability to interact with boron carbide (B4C) than dendritic cells, especially the preparation containing larger nanoparticles (B4C 2). Consequently, B4C 2 caused greater toxicity and induced the secretion of pro-inflammatory cytokines by these cells. However, migration assays demonstrated that macrophages loaded with B4C 1 migrated more efficiently than with B4C 2. Therefore, smaller nanoparticles (B4C 1) with lower toxicity but similar ability to activate macrophages proved to be more attractive.

CONCLUSIONS

Macrophages could be promising cellular carriers for boron carbide nanoparticle delivery, especially B4C 1 to the tumor microenvironment and thus prospective use in boron neutron capture therapy.

Nanotechnology in development of next generation of stent and related medical devices: Current and future aspects

Coronary stents have saved millions of lives in the last three decades by treating atherosclerosis especially, by preventing plaque protrusion and subsequent aneurysms. They attenuate the vascular SMC proliferation and promote reconstruction of the endothelial bed to ensure superior revascularization. With the evolution of modern stent types, nanotechnology has become an integral part of stent technology. Nanocoating and nanosurface fabrication on metallic and polymeric stents have improved their drug loading capacity as well as other mechanical, physico-chemical, and biological properties. Nanofeatures can mimic the natural nanofeatures of vascular tissue and control drug-delivery. This review will highlight the role of nanotechnology in addressing the challenges of coronary stents and the recent advancements in the field of related medical devices. Different generations of stents carrying nanoparticle-based formulations like liposomes, lipid-polymer hybrid NPs, polymeric micelles, and dendrimers are discussed highlighting their roles in local drug delivery and anti-restenotic properties. Drug nanoparticles like Paclitaxel embedded in metal stents are discussed as a feature of first-generation drug-eluting stents. Customized precision stents ensure safe delivery of nanoparticle-mediated genes or concerted transfer of gene, drug, and/or bioactive molecules like antibodies, gene mimics via nanofabricated stents. Nanotechnology can aid such therapies for drug delivery successfully due to its easy scale-up possibilities. However, limitations of this technology such as their potential cytotoxic effects associated with nanoparticle delivery that can trigger hypersensitivity reactions have also been discussed in this review. This article is categorized under: Implantable Materials and Surgical Technologies > Nanotechnology in Tissue Repair and Replacement Therapeutic Approaches and Drug Discovery > Nanomedicine for Cardiovascular Disease Therapeutic Approaches and Drug Discovery > Emerging Technologies.

Controlled Dissociation of Polymeric Micelles in Response to Oxidative Stress

Nanoparticle-based drug carriers that can respond to oxidative stress in tumor tissue have attracted attention for site-specific drug release. Taking advantage of the characteristic microenvironment in tumors, one of the attractive directions in drug delivery research is to design drug carriers that release drugs upon oxidation. A strategy to incorporate oxidation-sensitive thioether motifs such as thiomorpholine acrylamide (TMAM) to drug carriers has been often used to achieve oxidation-induced dissociation, thereby targeted drug release. However, those delivery systems often suffer from a slow dissociation rate due to the intrinsic hydrophobicity of the thioether structures. In this study, we aimed to enhance the dissociation rate of TMAM-based micelles upon oxidation. The random copolymers of N-isopropylacrylamide and TMAM (P(NIPAM/TMAM)) were designed as an oxidation-sensitive segment that showed a fast response to oxidative stress. We first synthesized P(NIPAM/TMAM) copolymers with different NIPAM:TMAM molar ratios. Those copolymers exhibited low critical solution temperatures (LCSTs) below 32 °C, which shifted to higher temperatures after oxidation. The changes in LCSTs depend on the NIPAM:TMAM molar ratios. At the NIPAM:TMAM molar ratio of 82:18, the LCSTs before and after oxidation were 17 and 54 °C, respectively. We then prepared micelles from the diblock copolymers of poly(N-acryloyl morpholine) (PAM) and P(NIPAM/TMAM). The micelles showed an accelerated dissociation rate upon oxidation compared to the micelles without NIPAM units. Furthermore, the doxorubicin (Dox)-loaded micelles showed enhanced relative toxicity in human colorectal cancer (HT29) cells over human umbilical vein endothelial cells (HUVECs). Our novel strategy to design an oxidation-sensitive micellar core comprising a P(NIPAM/TMAM) segment can be used as a chemotherapeutic delivery system that responds to an oxidative tumor microenvironment in an appropriate time scale.

Factors affecting the fate of nanoencapsulates post administration

Nanoencapsulation has found numerous applications in the food and nutraceutical industries. Micro and nanoencapsulated forms of bioactives have proven benefits in terms of stability, release, and performance in the body. However, the encapsulated ingredient is often subjected to a wide range of processing conditions and this is followed by storage, consumption, and transit along the gastrointestinal tract. A strong understanding of the fate of nanoencapsulates in the biological system is mandatory as it provides valuable insights for ingredient selection, formulation, and application. In addition to their efficacy, there is also the need to assess the safety of ingested nanoencapsulates. Given the rising research and commercial focus of this subject, this review provides a strong focus on their interaction factors and mechanisms, highlighting their prospective biological fate. This review also covers various approaches to studying the fate of nanoencapsulates in the body. Also, with emphasis on the overall scope, the need for a new advanced integrated common methodology to evaluate the fate of nanoencapsulates post-administration is discussed.

Macrophages as Promising Carriers for Nanoparticle Delivery in Anticancer Therapy

Macrophages play a critical role in the immune response due to their ability to recognize and remove pathogens, as well as present antigens, which are involved in inflammation, but they are also one of the most abundant immune cell populations present in the tumor microenvironment. In recent years, macrophages have become promising cellular carriers for drug and nanoparticle delivery to the tumor microenvironment, mainly due to their natural properties such as biocompatibility, degradability, lack of immunogenicity, long half-life in circulation, crossing biological barriers, and the possibility of migration and accumulation at a site of inflammation such as a tumor. For the effectiveness of this therapeutic strategy, known as "Trojan horse", it is important that the nanoparticles engulfed by macrophages do not affect their proper functioning. In our review, we discussed how the size, shape, chemical and mechanical properties of nanoparticles influence their internalization by macrophages. In addition, we described the promising research utilizing macrophages, their cell membranes and macrophage-derived exosomes as drug carriers in anticancer therapy. As a prospect of the wider use of this therapeutic strategy, we postulate its future application in boron delivery to the tumor environment in boron neutron capture therapy.

The mechanism, biopolymers and active compounds for the production of nanoparticles by anti-solvent precipitation: A review

The anti-solvent precipitation method has been investigated to produce biopolymeric nanoparticles in recent years. Biopolymeric nanoparticles have better water solubility and stability when compared with unmodified biopolymers. This review article focuses on the analysis of the state of the art available in the last ten years about the production mechanism and biopolymer type, as well as the used of these nanomaterials to encapsulate biological compounds, and the potential applications of biopolymeric nanoparticles in food sector. The revised literature revealed the importance to understand the anti-solvent precipitation mechanism since biopolymer and solvent types, as well as anti-solvent and surfactants used, can alter the biopolymeric nanoparticles properties. In general, these nanoparticles have been produced using polysaccharides and proteins as biopolymers, especially starch, chitosan and zein. Finally, it was identified that those biopolymers produced by anti-solvent precipitation were used to stabilize essential oils, plant extracts, pigments, and nutraceutical compounds, promoting their application in functional foods.

Poly-L-Lactic Acid Fillers Improved Dermal Collagen Synthesis by Modulating M2 Macrophage Polarization in Aged Animal Skin

Poly-L-lactic acid (PLLA) fillers correct cutaneous volume loss by stimulating fibroblasts to synthesize collagen and by augmenting the volume. PLLA triggers the macrophage-induced activation of fibroblasts that secrete transforming growth factor-β (TGF-β). However, whether M2 macrophage polarization is involved in PLLA-induced collagen synthesis via fibroblast activation in aged skin is not known. Therefore, we evaluated the effect of PLLA on dermal collagen synthesis via M2 polarization in an H₂O₂-induced cellular senescence model and aged animal skin. H₂O₂-treated macrophages had increased expression levels of the M1 marker CD80 and decreased expression levels of the M2 marker CD163, which were reversed by PLLA. The expression levels of interleukin (IL)-4 and IL-13, which mediate M2 polarization, were decreased in H₂O₂-treated macrophages and increased upon the PLLA treatment. CD163, IL-4, and IL-13 expression levels were decreased in aged skin, but increased after the PLLA treatment. The expression levels of TGF-β, pSMAD2/SMAD2, connective tissue growth factor (CTGF), alpha-smooth muscle actin (α-SMA), collagen type 1A1 (COL1A1), and COL3A1 were also decreased in aged skin, but increased after the PLLA treatment. Moreover, PLLA upregulated phosphatidylinositol 3-kinase p85α (PI3-kinase p85α)/protein kinase B (AKT) signaling, leading to fibroblast proliferation. PLLA decreased the expression of matrix metalloproteinase (MMP) 2 and MMP3, which destroy collagen and elastin fibers in aged skin. The amount of collagen and elastin fibers in aged skin increased following the PLLA treatment. In conclusion, PLLA causes M2 polarization by increasing IL-4 and IL-13 levels and upregulating TGF-β expression and collagen synthesis in aged skin.

Sustainable Biodegradable Biopolymer-Based Nanoparticles for Healthcare Applications

Biopolymeric nanoparticles are gaining importance as nanocarriers for various biomedical applications, enabling long-term and controlled release at the target site. Since they are promising delivery systems for various therapeutic agents and offer advantageous properties such as biodegradability, biocompatibility, non-toxicity, and stability compared to various toxic metal nanoparticles, we decided to provide an overview on this topic. Therefore, the review focuses on the use of biopolymeric nanoparticles of animal, plant, algal, fungal, and bacterial origin as a sustainable material for potential use as drug delivery systems. A particular focus is on the encapsulation of many different therapeutic agents categorized as bioactive compounds, drugs, antibiotics, and other antimicrobial agents, extracts, and essential oils into protein- and polysaccharide-based nanocarriers. These show promising benefits for human health, especially for successful antimicrobial and anticancer activity. The review article, divided into protein-based and polysaccharide-based biopolymeric nanoparticles and further according to the origin of the biopolymer, enables the reader to select the appropriate biopolymeric nanoparticles more easily for the incorporation of the desired component. The latest research results from the last five years in the field of the successful production of biopolymeric nanoparticles loaded with various therapeutic agents for healthcare applications are included in this review.

Comparative pulmonary toxicity assessment of tungsten trioxide and tungsten trioxide hydrate nanoparticles

Tungsten trioxide (WO₃)-based nanoparticles (NPs) are gaining popularity because of their exciting potential for photocatalytic applications; however, the toxic potential of WO₃-based NPs remains a concern. In this study, we evaluated the toxic risk of WO₃ NPs and hydrated WO₃ NPs (WO₃·H₂O NPs) using lung cells and explored the underlying mechanism. WO₃ NPs and WO₃·H₂O NPs significantly decreased the number of viable cells (59.5 %-85.8 % of control) and promoted apoptosis in human alveolar basal epithelial A549 cells after a 24-h exposure. Both WO₃ NPs and WO₃·H₂O NPs reduced the expression of heme oxygenase-1 (0.15-0.33 folds of control) and superoxide dismutase 2 (0.31-0.66 folds of control) and increased reactive oxygen species production (1.4-2.6 folds of control) and 8-hydroxy-2'-deoxyguanosine accumulation (1.22-1.43 folds of control). The results showed that WO₃ NPs have higher cytotoxicity and oxidative potential than WO₃·H₂O NPs. In addition, the WO₃ NP cellular uptake rate was significantly higher than the WO₃·H₂O NPs uptake rate in pulmonary cells. The greater extent of oxidative adverse effects induced by WO₃-based NPs appears to be related to the enhanced particle uptake. WO₃ NPs and WO₃·H₂O NPs exposure led to the secretion of inflammatory factor interleukin 6 (1.63-3.42 folds of control). Decreases in serpin family A member 1 gene expression (0.28-0.58 folds of control) and increases in the oxidation of neutrophil elastase inhibitor (1.34-1.62 folds of control) in pulmonary cells also suggest that exposure to WO₃ NPs and WO₃·H₂O NPs raises the risk of developing chronic obstructive pulmonary disease. Taken together, our findings indicate that the toxic risk of WO₃ NPs and WO₃·H₂O NPs must be considered when manufacturing and applying WO₃-based NPs.

Nanoformulation of the K-Ras(G12D)-inhibitory peptide KS-58 suppresses colorectal and pancreatic cancer-derived tumors

Single amino acid mutations of Ras occur in 30% of human cancers. In particular, K-Ras(G12D) has been detected in the majority of intractable colorectal and pancreatic cancers. Although efforts to target K-Ras(G12D) are currently underway, no effective drugs are available. We previously found that the K-Ras(G12D)-inhibitory bicyclic peptide KS-58 exhibits antitumor activity against syngeneic colon and orthotopic grafted pancreatic tumors; however, pristine KS-58 is difficult to handle because of low water solubility and it requires frequent administration to obtain sufficient antitumor activity. In this study, we used a nanoformulation of KS-58 prepared with the highly biocompatible surfactant Cremophor^® EL (CrEL) to improve water solubility and reduce the dosing frequency. Nanoformulations of KS-58 with CrEL dramatically improved its water solubility and increased its stability. Weekly intravenous administration of KS-58 nanoparticles (NPs) suppressed the growth of CT26 and PANC-1 cell-derived tumors in vivo, and fluorescent bioimaging indicated that the NP-encapsulated near-infrared fluorescent probe indocyanine green selectively accumulated in the tumor and was safely excreted through the kidneys following intravenous injection. Histopathological analysis of CT26 tumors and Western blotting of PANC-1 tumors revealed that KS-58 NPs reduced ERK phosphorylation, a downstream signal of K-Ras(G12D). Our results suggest that KS-58 NPs represent a novel therapeutic agent for treating colorectal and pancreatic cancers.

Colloidal Polyelectrolyte Complexes from Hyaluronic Acid: Preparation and Biomedical Applications

Hyaluronic acid (HA) is a naturally occurring polysaccharide which has been extensively exploited in biomedical fields owing to its outstanding biocompatibility. Self-assembly of HA and polycations through electrostatic interactions can generate colloidal polyelectrolyte complexes (PECs), which can offer a wide range of applications while being relatively simple to prepare with rapid and "green" processes. The advantages of colloidal HA-based PECs stem from the combined benefits of nanomedicine, green chemistry, and the inherent properties of HA, namely high biocompatibility, biodegradability, and biological targeting capability. Accordingly, colloidal PECs from HA have received increasing attention in the recent years as high-performance materials for biomedical applications. Considering their potential, this review is aimed to provide a comprehensive understanding of colloidal PECs from HA in complex with polycations, from the most fundamental aspects of the preparation process to their various biomedical applications, notably as nanocarriers for delivering small molecule drugs, nucleic acids, peptides, proteins, and bioimaging agents or the construction of multifunctional platforms.

Understanding the Phagocytosis of Particles: the Key for Rational Design of Vaccines and Therapeutics

A robust comprehension of phagocytosis is crucial for understanding its importance in innate immunity. A detailed description of the molecular mechanisms that lead to the uptake and clearance of endogenous and exogenous particles has helped elucidate the role of phagocytosis in health and infectious or autoimmune diseases. Furthermore, knowledge about this cellular process is important for the rational design and development of particulate systems for the administration of vaccines or therapeutics. Depending on these specific applications and the required biological responses, particles must be designed to encourage or avoid their phagocytosis and prolong their circulation time. Functionalization with specific polymers or ligands and changes in the size, shape, or surface of particles have important effects on their recognition and internalization by professional and nonprofessional phagocytes and have a major influence on their fate and safety. Here, we review the phagocytosis of particles intended to be used as carrier or delivery systems for vaccines or therapeutics, the cells involved in this process depending on the route of administration, and the strategies employed to obtain the most desirable particles for each application through the manipulation of their physicochemical characteristics. We also offer a view of the challenges and potential opportunities in the field and give some recommendations that we expect will enable the development of improved approaches for the rational design of these systems.

Lipid based nanoparticles as a novel treatment modality for hepatocellular carcinoma: a comprehensive review on targeting and recent advances

Liver cancer is considered one of the deadliest diseases with one of the highest disease burdens worldwide. Among the different types of liver cancer, hepatocellular carcinoma is considered to be the most common type. Multiple conventional approaches are being used in treating hepatocellular carcinoma. Focusing on drug treatment, regular agents in conventional forms fail to achieve the intended clinical outcomes. In order to improve the treatment outcomes, utilizing nanoparticles-specifically lipid based nanoparticles-are considered to be one of the most promising approaches being set in motion. Multiple forms of lipid based nanoparticles exist including liposomes, solid lipid nanoparticles, nanostructured lipid carriers, microemulsion, nanoemulsion, phytosomes, lipid coated nanoparticles, and nanoassemblies. Multiple approaches are used to enhance the tumor uptake as well tumor specificity such as intratumoral injection, passive targeting, active targeting, and stimuli responsive nanoparticles. In this review, the effect of utilizing lipidic nanoparticles is being discussed as well as the different tumor uptake enhancement techniques used.

Emerging prospects of protein/peptide-based nanoassemblies for drug delivery and vaccine development

Proteins have been widely used in the biomedical field because of their well-defined architecture, accurate molecular weight, excellent biocompatibility and biodegradability, and easy-to-functionalization. Inspired by the wisdom of nature, increasing proteins/peptides that possess self-assembling capabilities have been explored and designed to generate nanoassemblies with unique structure and function, including spatially organized conformation, passive and active targeting, stimuli-responsiveness, and high stability. These characteristics make protein/peptide-based nanoassembly an ideal platform for drug delivery and vaccine development. In this review, we focus on recent advances in subsistent protein/peptide-based nanoassemblies, including protein nanocages, virus-like particles, self-assemblable natural proteins, and self-assemblable artificial peptides. The origin and characteristics of various protein/peptide-based assemblies and their applications in drug delivery and vaccine development are summarized. In the end, the prospects and challenges are discussed for the further development of protein/peptide-based nanoassemblies.

Gliadin-mediated green preparation of hybrid zinc oxide nanospheres with antibacterial activity and low toxicity

The development of inorganic antibacterial agents that impart antibacterial properties to biomaterials has attracted wide attention. The paper introduced a kind of hybrid nanosphere antibacterial agent composed of wheat gliadin (WG) and zinc oxide (ZnO), with antibacterial efficacy and low toxicity. The ZnO/WG hybrid nanospheres were environment-friendly integrated by molecular self-assembly co-precipitating and freeze-drying transformation, and were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), atomic absorption spectroscopy (AAS), specific surface and pore size analysis, bacteriostasis test, reactive oxygen species (ROS) determination and safety evaluation. It was found that the prepared hybrid nanospheres were composed of two components, WG and ZnO, with a diameter scope of 100–200 nm; the content of ZnO in the hybrid nanospheres can reach 46.9–70.2% (w/w); the bacteriostasis tests proved that the prepared ZnO/WG nanospheres generating ROS, have a significant inhibitory effect on E. coli and S. aureus; furthermore, the ZnO/WG nanospheres are relatively safe and highly biocompatible in cells and mice. Therefore, the prepared novel ZnO/WG hybrid nanospheres were supposed to apply in the preparation of anti-infective wound dressings, tissue engineering skin scaffold materials, food, and cosmetics preservatives, and so on.