Strategies in the design of nanoparticles for therapeutic applications

Peptide-decorated nanocarriers penetrating the blood-brain barrier for imaging and therapy of brain diseases

Blood-Brain Barrier (BBB) is one of the most important physiological barriers strictly restricting the substance exchange between blood and brain tissues. While the BBB protects the brain from infections and toxins and maintains brain homeostasis, it is also recognized as the main obstacle to the penetration of therapeutics and imaging agents into the brain. Due to high specificity and affinity, peptides are frequently exploited to decorate nanocarriers across the BBB for diagnosis and/or therapy purposes. However, there are still some challenges that restrict their clinical application, such as stability, safety and immunocompatibility. In this review, we summarize the biological and pathophysiological characteristics of the BBB, strategies across the BBB, and recent progress on peptide decorated nanocarriers for brain diseases diagnosis and therapy. The challenges and opportunities for their translation are also discussed.

Amelioration of systemic antitumor immune responses in cocktail therapy by immunomodulatory nanozymes

Nanozymes that mimic natural enzyme-like activities have gradually emerged in cancer therapy. To overcome the bottlenecks of single-mode nanozymes, including "off-target" toxicity and ineffectiveness toward metastatic cancers, we designed magnetic nanoparticle-based multifunctional visualized immunomodulatory nanozymes. Besides the partial initiation of the prime immune response by intrinsic immunogenicity, as a smart drug delivery system with a temperature- and pH-sensitive dual response to the tumor microenvironment, these nanozymes released immune agonists to boost enhanced systemic immune response, eventually ameliorating the cancer immune microenvironment through many aspects: activating dendritic cells, improving the function of CD8⁺ T cells, and decreasing the population of myeloid-derived suppressor cells, which inhibited both primary and metastatic cancers. Mechanistically, these nanozymes regulated the reactive oxygen species-related Akt signaling pathway and consequently activated cell apoptosis-related signaling pathways, which provided a deeper understanding of the synergistic mechanism of multifunctional nanozymes. Our findings offer a promising imaging-guided cocktail therapy strategy through immunomodulatory nanozymes.

Scalable Manufacture of Curcumin-Loaded Chitosan Nanocomplex for pH-Responsive Delivery by Coordination-Driven Flash Nanocomplexation

Metal coordination-driven nanocomplexes are known to be responsive to physiologically relevant stimuli such as pH, redox, temperature or light, making them well-suited for antitumor drug delivery. The ever-growing demand for such nanocomplexes necessitates the design of a scalable approach for their production. In this study, we demonstrate a novel coordination self-assembly strategy, termed flash nanocomplexation (FNC), which is rapid and efficient for the fabrication of drug-loaded nanoparticles (NPs) in a continuous manner. Based on this strategy, biocompatible chitosan (CS) and Cu2+ can be regarded anchors to moor the antitumor drug (curcumin, Cur) through coordination, resulting in curcumin-loaded chitosan nanocomplex (Cur-loaded CS nanocomplex) with a narrow size distribution (PDI < 0.124) and high drug loading (up to 41.75%). Owing to the excellent stability of Cur-loaded CS nanocomplex at neutral conditions (>50 days), premature Cur leakage was limited to lower than 1.5%, and pH-responsive drug release behavior was realized in acidic tumor microenvironments. An upscaled manufacture of Cur-loaded CS nanocomplex is demonstrated with continuous FNC, which shows an unprecedented method toward practical applications of nanomedicine for tumor therapy. Furthermore, intracellular uptake study and cytotoxicity experiments toward H1299 cells demonstrates the satisfied anticancer efficacy of the Cur-loaded CS nanocomplex. These results confirm that coordination-driven FNC is an effective method that enables the rapid and scalable fabrication of antitumor drugs.

Nanotechnology Role Development for COVID-19 Pandemic Management

The global outbreak of coronavirus disease has sent an ominous message to the field of innovative and advanced technology research and development (COVID-19). To accomplish this, convectional technology and recent discoveries can be combined, or new research directions can be opened up using nanotechnology. Nanotechnology can be used to prevent, diagnose, and treat SARS-CoV-2 infection. As the pandemic spreads, a thorough examination of nanomaterials' role in pandemic response is highly desirable. According to this comprehensive review article, nanotechnology can be used to prevent, diagnose, and treat COVID-19. This research will be extremely useful during the COVID-19 outbreak in terms of developing rules for designing nanostructure materials to combat the outbreak.

Microgels Formed by Spontaneous Click Chemistries Utilizing Microfluidic Flow Focusing for Cargo Release in Response to Endogenous or Exogenous Stimuli

Protein therapeutics have become increasingly popular for the treatment of a variety of diseases owing to their specificity to targets of interest. However, challenges associated with them have limited their use for a range of ailments, including the limited options available for local controlled delivery. To address this challenge, degradable hydrogel microparticles, or microgels, loaded with model biocargoes were created with tunable release profiles or triggered burst release using chemistries responsive to endogenous or exogeneous stimuli, respectively. Specifically, microfluidic flow-focusing was utilized to form homogenous microgels with different spontaneous click chemistries that afforded degradation either in response to redox environments for sustained cargo release or light for on-demand cargo release. The resulting microgels were an appropriate size to remain localized within tissues upon injection and were easily passed through a needle relevant for injection, providing means for localized delivery. Release of a model biopolymer was observed over the course of several weeks for redox-responsive formulations or triggered for immediate release from the light-responsive formulation. Overall, we demonstrate the ability of microgels to be formulated with different materials chemistries to achieve various therapeutic release modalities, providing new tools for creation of more complex protein release profiles to improve therapeutic regimens.

Biofunctionalized Nanomaterials: Alternative for Encapsulation Process Enhancement

In recent years, interest in the development of nanometric materials with specific characteristics has grown; however, there are few scientific contributions that associate encapsulation methodologies and matrices with the particle objective (metabolic directions, type of administration, biological impact, and biocompatibility). This review focuses on describing the benefits and disadvantages of different techniques for designing custom particles and alternatives for the biofunctionalization nanomaterials regarding the biological impact of a nanomaterial with potential use in foods known as nutraceuticals. The study of optical properties, physicochemical factors, and characteristics such as rheological can predict its stability in the application matrix; however, not only should the characterization of a nanocomposite with applications in food be considered, but also the biological impact that it may present.

The morphological role of ligand inhibitors in blocking receptor- and clathrin-mediated endocytosis

Cells often internalize particles through endocytic pathways that involve the binding between cell receptors and particle ligands, which drives the cell membrane to wrap the particle into a delivery vesicle. Previous findings showed that receptor-mediated endocytosis is impossible for spherical particles smaller than a minimum size because of the energy barrier created by membrane bending. In this study, we investigate the morphological role of ligand inhibitors in blocking endocytosis, inspired by antibodies that inhibit virus ligands to prevent infection. While ligand inhibitors have the obvious effect of reducing the driving force due to adhesion, they also have a nontrivial (morphological) impact on the entropic and elastic energy of the system. We determine the necessary conditions for endocytosis by considering the additional energy barrier due to the membrane bending to wrap the inhibiting protrusions. We find that inhibitors increase the minimum radius previously reported, depending on their density and size. In addition, we extend this result to the case of clathrin-mediated endocytosis, which is the most common pathway for virus entry. The assembly of a clathrin coat with a spontaneous curvature increases the energy barrier and sets a maximum particle size (in agreement with experimental observations on spherical particles). Our investigation suggests that morphological considerations can inform the optimal design of neutralizing viral antibodies and new strategies for targeted nanomedicine.

Nanoparticles for Coronavirus Control

More than 2 years have passed since the SARS-CoV-2 outbreak began, and many challenges that existed at the beginning of this pandemic have been solved. Some countries have been able to overcome this global challenge by relying on vaccines against the virus, and vaccination has begun in many countries. Many of the proposed vaccines have nanoparticles as carriers, and there are different nano-based diagnostic approaches for rapid detection of the virus. In this review article, we briefly examine the biology of SARS-CoV-2, including the structure of the virus and what makes it pathogenic, as well as describe biotechnological methods of vaccine production, and types of the available and published nano-based ideas for overcoming the virus pandemic. Among these issues, various physical and chemical properties of nanoparticles are discussed to evaluate the optimal conditions for the production of the nano-mediated vaccines. At the end, challenges facing the international community and biotechnological answers for future viral attacks are reviewed.

Self-assembling protein nanocarrier for selective delivery of cytotoxic polypeptides to CXCR4+ head and neck squamous cell carcinoma tumors

Loco-regional recurrences and distant metastases represent the main cause of head and neck squamous cell carcinoma (HNSCC) mortality. The overexpression of chemokine receptor 4 (CXCR4) in HNSCC primary tumors associates with higher risk of developing loco-regional recurrences and distant metastases, thus making CXCR4 an ideal entry pathway for targeted drug delivery. In this context, our group has generated the self-assembling protein nanocarrier T22-GFP-H6, displaying multiple T22 peptidic ligands that specifically target CXCR4. This study aimed to validate T22-GFP-H6 as a suitable nanocarrier to selectively deliver cytotoxic agents to CXCR4⁺ tumors in a HNSCC model. Here we demonstrate that T22-GFP-H6 selectively internalizes in CXCR4⁺ HNSCC cells, achieving a high accumulation in CXCR4⁺ tumors in vivo, while showing negligible nanocarrier distribution in non-tumor bearing organs. Moreover, this T22-empowered nanocarrier can incorporate bacterial toxin domains to generate therapeutic nanotoxins that induce cell death in CXCR4-overexpressing tumors in the absence of histological alterations in normal organs. Altogether, these results show the potential use of this T22-empowered nanocarrier platform to incorporate polypeptidic domains of choice to selectively eliminate CXCR4⁺ cells in HNSCC. Remarkably, to our knowledge, this is the first study testing targeted protein-only nanoparticles in this cancer type, which may represent a novel treatment approach for HNSCC patients.

Biocompatible Nanoparticles Based on Amphiphilic Random Polypeptides and Glycopolymers as Drug Delivery Systems

In this research, the development and investigation of novel nanoobjects based on biodegradable random polypeptides and synthetic non-degradable glycopolymer poly(2-deoxy-2-methacrylamido-d-glucose) were proposed as drug delivery systems. Two different approaches have been applied for preparation of such nanomaterials. The first one includes the synthesis of block-random copolymers consisting of polypeptide and glycopolymer and capable of self-assembly into polymer particles. The synthesis of copolymers was performed using sequential reversible addition-fragmentation chain transfer (RAFT) and ring-opening polymerization (ROP) techniques. Amphiphilic poly(2-deoxy-2-methacrylamido-d-glucose)-b-poly(l-lysine-co-l-phenylalanine) (PMAG-b-P(Lys-co-Phe)) copolymers were then used for preparation of self-assembled nanoparticles. Another approach for the formation of polypeptide-glycopolymer particles was based on the post-modification of preformed polypeptide particles with an oxidized glycopolymer. The conjugation of the polysaccharide on the surface of the particles was achieved by the interaction of the aldehyde groups of the oxidized glycopolymer with the amino groups of the polymer on particle surface, followed by the reduction of the formed Schiff base with sodium borohydride. A comparative study of polymer nanoparticles developed with its cationic analogues based on random P(Lys-co-d-Phe), as well as an anionic one—P(Lys-co-d-Phe) covered with heparin––was carried out. In vitro antitumor activity of novel paclitaxel-loaded PMAG-b-P(Lys-co-Phe)-based particles towards A549 (human lung carcinoma) and MCF-7 (human breast adenocarcinoma) cells was comparable to the commercially available Paclitaxel-LANS.

Nanocarriers for Drug Delivery: An Overview with Emphasis on Vitamin D and K Transportation

Mounting evidence shows that supplementation with vitamin D and K or their analogs induces beneficial effects in various diseases, e.g., osteoarticular, cardiovascular, or carcinogenesis. The use of drugs delivery systems via organic and inorganic nanocarriers increases the bioavailability of vitamins and analogs, enhancing their cellular delivery and effects. The nanotechnology-based dietary supplements and drugs produced by the food and pharmaceutical industries overcome the issues associated with vitamin administration, such as stability, absorption or low bioavailability. Consequently, there is a continuous interest in optimizing the carriers' systems in order to make them more efficient and specific for the targeted tissue. In this pioneer review, we try to circumscribe the most relevant aspects related to nanocarriers for drug delivery, compare different types of nanoparticles for vitamin D and K transportation, and critically address their benefits and disadvantages.

Fabrication of Microbicidal Silver Nanoparticles: Green Synthesis and Implications in the Containment of Bacterial Biofilm on Orthodontal Appliances

Among various metal-based nanoparticles, silver nanoparticles (AgNPs) manifest superior inhibitory effects against several microorganisms. In fact, the AgNP-based treatment has been reported to inhibit both sensitive and resistant isolates of bacteria and other disease-causing microbes with equal propensity. Keeping this fact into consideration, we executed bio-mediated synthesis of AgNPs employing extract of flower and various other parts (such as bud and leaf) of the Hibiscus rosa-sinensis plant. The physicochemical characterization of as-synthesized AgNPs was executed employing transmission electron microscopy (TEM), dynamic light scattering (DLS), zeta potential, Fourier transform infrared (FTIR) spectroscopy, and UV-Vis spectroscopy, etc. The as-synthesized AgNPs demonstrated strong antimicrobial activity against both Gram-positive and Gram-negative bacteria with equal propensity. The as-synthesized AgNPs successfully inhibited Streptococcus mutans (S. mutans), one of the main causative bacteria responsible for dental caries. Considering the fact that orthodontic appliances facilitate infliction of the oral cavity with a range of microbes including S. mutans, we determined the growth inhibitory and anti-adherence activities of AgNPs on orthodontic appliances. We performed microbiological assays employing AgNPs adsorbed onto the surface of nickel–titanium (Ni-Ti) orthodontic wires. A topographic analysis of the decontaminated Ni-Ti orthodontic wires was performed by scanning electron microscopy. In addition to antimicrobial and anti-biofilm activities against oral S. mutans, the as-fabricated AgNPs demonstrated significant inhibitory and anti-biofilm properties against other biofilm-forming bacteria such as Escherichia coli and Listeria monocytogenes.

Near-Infrared Afterglow Luminescence of Chlorin Nanoparticles for Ultrasensitive In Vivo Imaging

Afterglow imaging holds great potential for ultrasensitive biomedical imaging. As it detects photons after the cessation of real-time light excitation, autofluorescence can therefore be effectively eliminated. However, afterglow imaging is still in its infant stage due to the lack of afterglow agents with satisfactory lifetime, biocompatibility, and high luminescence brightness, particularly afterglow in the near-infrared region for in vivo applications. To address these issues, this study for the first time reports chlorin nanoparticles (Ch-NPs) emitting afterglow luminescence peaking at 680 nm with a half-life of up to 1.5 h, which is almost 1 order of magnitude longer than those of other reported organic afterglow probes. In-depth experimental and theoretical studies revealed that the brightness of the afterglow luminescence is strongly correlated with the singlet oxygen (¹O₂) capacity and the oxidizability of the chlorins. Benefitting from the ultralong half-life and the minimized imaging background, small metastatic tumor foci of 3 mm³ were successfully resected under the guidance of the afterglow luminescence generated upon a single shot of activation prior to the injection, which was impossible for conventional near-infrared fluorescence imaging due to tissue autofluorescence.

Tumor-Microenvironment-Responsive Biodegradable Nanoagents Based on Lanthanide Nucleotide Self-Assemblies toward Precise Cancer Therapy

Stimuli-responsive nanoagents, which simultaneously satisfy normal tissue clearance and tumor-specific responsive treatment, are highly attractive for precise cancer theranostics. Herein, we develop a unique template-induced self-assembly strategy for the exquisitely controlled synthesis of self-assembled lanthanide (Ln³⁺ ) nucleotide nanoparticles (LNNPs) with amorphous structure and tunable size from sub-5 nm to 105 nm. By virtue of the low-temperature (10 K) and high-resolution spectroscopy, the local site symmetry of Ln³⁺ in LNNPs is unraveled for the first time. The proposed LNNPs are further demonstrated to possess the ability for highly efficient loading and tumor-microenvironment-responsive release of doxorubicin. Particularly, sub-5 nm LNNPs not only exhibit excellent biocompatibility and predominant renal-clearance performance, but also enable efficient tumor retention. These findings reveal the great potential of LNNPs as a new generation of therapeutic platform to overcome the dilemma between efficient therapy and long-term toxicity of nanoagents for future clinical applications.

Protein corona-driven nanovaccines improve antigen intracellular release and immunotherapy efficacy

During vaccine delivery in vivo, the vaccine carrier dynamically adsorbs the surrounding proteins or biomacromolecules to form a protein corona layer, which determines the physiological and therapeutic responses of the vaccine. Although the importance of the protein corona effect in drug delivery is widely accepted, understanding of the rational use of the protein corona to improve antigen controlled release is still sparse. Here, we constructed a protein corona-driven nanovaccine (PCNV), which has the dual effects of resisting the protein corona-induced antigen extracellular release and promoting protein corona-triggered antigen cytosolic release under reductive conditions. Specifically, the nanovaccine was formulated via the assembly of fluorinated dendrigraft-poly-lysine and cleavable antigen-CpG conjugate. Before entering antigen-presenting cells (APCs), the anchoring effect of CpG was used to avoid the dissociation of antigens from the carrier even under the protein corona effect. While nanovaccine enters the APCs, the intracellular reducing conditions can induce a break in the disulfide bond between CpG and antigen. Notably, at the same time, the intracellular protein corona effect triggers antigen release from the carrier and achieves efficient antigen presentation. In addition, the PCNV produced a significant prophylactic and therapeutic antitumor response in the mouse model. Therefore, the rational use of the protein corona effect provides an effective strategy for vaccine delivery.

Biogenic Synthesis of Antibacterial, Hemocompatible, and Antiplatelets Lysozyme Functionalized Silver Nanoparticles through the One-Step Process for Therapeutic Applications

To evaluate silver nanoparticles’ (AgNPs) therapeutic and clinical potentials, antibacterial action, blood compatibility, and antiplatelet activities are the main concerns for toxicity profiling. Heat-denatured lysozyme-mediated formulation stabilized the AgNPs, thereby providing more bactericidal activity and blood compatibility. The study of the synthesis of AgNPs suggests the rapid and cost-effective formulation of AgNPs by one-step reaction using a 10:1 ratio of silver nitrate and lysozyme by incubating at 60 °C for two hours. Characterization of AgNPs was analyzed by UV–Visible spectroscopy, DLS, TEM, EDX, XRD, AFM, and FTIR, followed by antibacterial, hemocompatibility, and platelet aggregation testing. The average size of synthesized AgNPs was found to be 94.10 nm with 0.45 mV zeta potential and 0.293 polydispersity index by DLS. The TEM and EXD results indicated homogeneously 28.08 nm spherical-shaped pure formations of AgNPs. The XRD peaks showed the synthesis of small AgNPs with a crystallite size of 22.88 nm, while the AFM confirmed the homogeneity and smoothness of the monodispersed AgNPs. The FTIR spectra specified the coating of the lysozyme-derived amide group on the AgNPs surface, which provides stability and functionality of nanoparticles. The antibacterial activity of AgNPs was remarkable against six pathogenic bacteria and three multidrug resistance (MDR) strains (i.e., Escherichia coli, Klebsiella aerogenes, and Pseudomonas aeruginosa), which exhibited inhibition zones with diameters ranging between 13.5 ±  0.2 mm to 19.0 ±  0.3 mm. The non-hemolytic nature of the AgNPs was calculated by percentage hemolysis with four concentrations. The negative result of platelet aggregation using platelet-rich plasma suggests the antiplatelet effect of AgNPs. Only minor hemolysis of 6.17% in human erythrocytes and mild platelet aggregation of 1.98% were induced, respectively, by the use of 1000 µL of 1 mM AgNPs, which contains approximately 107.8 μg silver. The results indicated that the antiplatelet potency and non-hemolytic nature with the antibacterial action of the lysozyme functionalized AgNPs have a good chance to be used to solve in-stent restenosis and thrombosis issues of the coronary stent and may also have a possibility to use in vaccination to resolve the blood clotting problem. So, the optimized biogenic formulation of AgNPs offers promising opportunities to be used as a therapeutic agent.

Size and Charge Characterization of Lipid Nanoparticles for mRNA Vaccines

Messenger RNA vaccines have come into the spotlight as a promising and adaptive alternative to conventional vaccine approaches. The efficacy of mRNA vaccines relies on the ability of mRNA to reach the cytoplasm of cells, where it can be translated into proteins of interest, allowing it to trigger the immune response. However, unprotected mRNA is unstable and susceptible to degradation by exo- and endonucleases, and its negative charges are electrostatically repulsed by the anionic cell membranes. Therefore, mRNA needs a delivery system that protects the nucleic acid from degradation and allows it to enter into the cells. Lipid nanoparticles (LNPs) represent a nonviral leading vector for mRNA delivery. Physicochemical parameters of LNPs, including their size and their charge, directly impact their in vivo behavior and, therefore, their cellular internalization. In this work, Taylor dispersion analysis (TDA) was used as a new methodology for the characterization of the size and polydispersity of LNPs, and capillary electrophoresis (CE) was used for the determination of LNP global charge. The results obtained were compared with those obtained by dynamic light scattering (DLS) and laser Doppler electrophoresis (LDE).

Spatiotemporal Tracing of the Cellular Internalization Process of Rod-Shaped Nanostructures

Endocytosis, as one of the main ways for nanostructures enter cells, is affected by several aspects, and shape is an especially critical aspect during the endocytosis of nanostructures. However, it has remained challenging to capture the dynamic internalization behaviors of rod-shaped nanostructures while also probing the mechanical aspects of the internalization. Here, using the atomic force microscopy-based force tracing technique, transmission electron microscopy, and molecular dynamic simulation, we mapped the detailed internalization behaviors of rod-shaped nanostructures with different aspect ratios at the single-particle level. We found that the gold nanorod is endocytosed in a noncontinuous and force-rebound rotation manner, herein named "intermittent rotation". The force tracing test indicated that the internalization force (∼81 pN, ∼108 pN, and ∼157 pN) and time (∼0.56 s, ∼0.66 s, and ∼1.14 s for a 12.10 nm × 11.96 nm gold nanosphere and 26.15 nm × 13.05 nm and 48.71 nm × 12.45 nm gold nanorods, respectively) are positively correlated with the aspect ratios. However, internalization speed is negatively correlated with internalization time, irrespective of the aspect ratio. Further, the energy analysis suggested that intermittent rotation from the horizontal to vertical direction can reduce energy dissipation during the internalization process. Thus, to overcome the energy barrier of internalization, the number and angle of rotation increases with aspect ratios. Our findings provide critical missing evidence of rod-shaped nanostructure's internalization, which is essential for fundamentally understanding the internalization mechanism in living cells.

Delivery of mRNA for regulating functions of immune cells

Abnormal immune cell functions are commonly related to various diseases, including cancer, autoimmune diseases, and infectious diseases. Messenger RNA (mRNA)-based therapy can regulate the functions of immune cells or assign new functions to immune cells, thereby generating therapeutic immune responses to treat these diseases. However, mRNA is unstable in physiological environments and can hardly enter the cytoplasm of target cells; thus, effective mRNA delivery systems are critical for developing mRNA therapy. The two mRNA vaccines of Pfizer-BioNTech and Moderna have demonstrated that lipid nanoparticles (LNPs) can deliver mRNA into dendritic cells (DCs) to induce immunization against severe acute respiratory syndrome coronavirus 2, which opened the floodgates to the development of mRNA therapy. Apart from DCs, other immune cells are promising targets for mRNA therapy. This review summarized the barriers to mRNA delivery and advances in mRNA delivery for regulating the functions of different immune cells.

Synthesis of silymarin-selenium nanoparticle conjugate and examination of its biological activity in vitro

Silymarin (Sil) was conjugated to selenium nanoparticles (SeNPs) to increase Sil bioavailability. The conjugates were monodisperse; the average diameter of the native SeNPs was ~ 20-50 ± 1.5 nm, whereas that of the conjugates was 30-50 ± 0.5 nm. The use of SeNPs to increase the bioavailability of Sil was examined with the MH-22a, EPNT-5, HeLa, Hep-2, and SPEV-2 cell lines. The EPNT-5 (glioblastoma) cells were the most sensitive to the conjugates compared to the conjugate-free control. The conjugates increased the activity of cellular dehydrogenases and promoted the penetration of Sil into the intracellular space. Possibly, SeNPs play the main part in Sil penetration of cells and Sil penetration is not associated with phagocytosis. Thus, SeNPs are promising for use as a Sil carrier and as protective antigens.

Current methods and emerging approaches for detection of programmed death ligand 1

Various tumor cells overexpress programmed death ligand 1 (PD-L1), a main immune checkpoint protein (ICP) embedded in the tumor cells membrane, to evade immune recognition through the interaction between PD-L1 and its receptor programmed death 1 (PD-1) which is from T-cells for maintaining immune tolerance. So inhibitors targeting the PD-1 or PD-L1 can block the PD-1/PD-L1 signaling pathway to restore the recognition activity of the immune system to tumor cells, which also have been utilized as a novel approach to improve the clinical therapeutic effect for cancer patients. Since not all cancer patients can respond to these inhibitors effectively, previous diagnosis of PD-L1 is significant to target the right treatments for cancer patients. This review pays attention to the PD-L1 detection and recent progress in the measurement of PD-L1 concentration, including various detection methods based on optical sensors as well as electrochemical assays. Apart from above those, we also focus on the prospects of PD-L1 detection in precision medicine.

Selenium Nanoparticles Biosynthesized by Pantoea agglomerans and Their Effects on Cellular and Physiological Parameters in the Rainbow Trout Oncorhynchus mykiss

Simple Summary

Nanoparticles (Nps), new biotechnological tools, possess unique physical and chemical properties and are increasingly being used in several fields, such as manufacture, medicine and veterinary medicine. In this work, we evaluated the effects of selenium (Se) nanoparticles stabilized with L-Cysteine (Se⁰Nps/L-Cys) as a nutritional supplement, to modulate immunological, oxidative status, and productive parameters in O. mykiss. The results demonstrated that Se⁰Nps/L-Cys showed less toxicity and higher antioxidant activity than Se⁰Nps and Na₂SeO₃. The Se⁰Nps/L-Cys, as a dietary supplement, had a significantly better effect on both immunological and physiological parameters, causing improvements at the productive level of O. mykiss when compared with Se⁰Nps and Na₂SeO₃. We concluded that Se⁰Nps sythetised by P. agglomerans, used as dietary supplement, is an environmentally friendly and promising alternative for nutritional supplementation for O. mykiss.

Abstract

The applications of nanoparticles (Nps) as food additives, health enhancers, and antimicrobials in animal production are increasing. The aim of this study was to evaluate the effect of selenium (Se) nanoparticles (Se⁰Nps) stabilized with L-cysteine (Se⁰Nps/L-Cys), as a nutritional supplement, on immunological, oxidative status, and productive parameters in O. mykiss. TEM and SEM-EDS showed the accumulation of spherical Se⁰Nps entirely composed by elemental selenium (Se⁰) as intracellular and extracellular deposits in Pantoea agglomerans UC-32 strain. The in vitro antioxidant capacity of Se⁰Nps/L-Cys was significant more efficient ROS scavengers than Se⁰Nps and Na₂SeO₃. We also evaluate the effect of Se⁰Nps/L-Cys on cell viability and oxidative stress in RTgill-W1, RTS-11, or T-PHKM Oncorhynchus mykiss cell lines. Se⁰Nps/L-Cys showed less toxic and high antioxidant activity than Se⁰Nps and Na₂SeO₃. Finally, the dietary Se⁰Nps/L-Cys had a significant better effect on both plasma lysozyme and respiratory burst activity (innate immune response), on tissular Gpx activity (oxidative status), and on well-being (productive parameter) of O. mykiss when it is compared to Se⁰Nps and Na₂SeO₃. Se⁰Nps/L-Cys is a promising alternative for nutritional supplement for O. mykiss with better performance than Na₂SeO₃ and Se⁰Nps, ease to implementation, and reduced environmental impact.

Fluorescence Correlation Spectroscopy Monitors the Fate of Degradable Nanocarriers in the Blood Stream

The use of nanoparticles as carriers to deliver pharmacologically active compounds to specific parts of the body via the bloodstream is a promising therapeutic approach for the effective treatment of various diseases. To reach their target sites, nanocarriers (NCs) need to circulate in the bloodstream for prolonged periods without aggregation, degradation, or cargo loss. However, it is very difficult to identify and monitor small-sized NCs and their cargo in the dense and highly complex blood environment. Here, we present a new fluorescence correlation spectroscopy-based method that allows the precise characterization of fluorescently labeled NCs in samples of less than 50 μL of whole blood. The NC size, concentration, and loading efficiency can be measured to evaluate circulation times, stability, or premature drug release. We apply the new method to follow the fate of pH-degradable fluorescent cargo-loaded nanogels in the blood of live mice for periods of up to 72 h.

Leveraging self-assembled nanobiomaterials for improved cancer immunotherapy

Nanomaterials and targeted drug delivery vehicles improve the therapeutic index of drugs and permit greater control over their pharmacokinetics, biodistribution, and bioavailability. Here, nanotechnologies applied to cancer immunotherapy are discussed with a focus on current and next generation self-assembling drug delivery systems composed of lipids and/or polymers. Topics covered include the fundamental design, suitability, and inherent properties of nanomaterials that induce anti-tumor immune responses and support anti-cancer vaccination. Established active and passive targeting strategies as well as newer "indirect" methods are presented together with insights into how nanocarrier structure and surface chemistry can be leveraged for controlled delivery to the tumor microenvironment while minimizing off-target effects.

Surface Free Energy of Titanium Disks Enhances Osteoblast Activity by Affecting the Conformation of Adsorbed Fibronectin

This study evaluated the influence of surface free energy (SFE) of titanium disks on the adsorption and conformation of fibronectin (FN) and the biological behavior of osteoblasts cultured on the FN-treated modified surfaces. High [H]-SFE titanium disks were irradiated by a 30 W UV light, while low (L)-SFE titanium disks received no treatment. The surface characteristics of the titanium disks were examined using scanning electron microscope, optical surface profilometer, X-ray photoelectron spectroscopy, and contact angle measurements. Adsorbed FN on different groups was investigated using attenuated total reflection-Fourier transform infrared spectroscopy. MG-63 cells were cultured on FN-treated titanium disks to evaluate the in vitro bioactivity. The experiment showed H-SFE titanium disks adsorbed more FN and acquired more ß-turn content than L-SFE group. MG-63 cells cultured on FN-treated H-SFE titanium disks showed better osteogenic responses, including adhesion, proliferation, alkaline phosphatase activity and mineralization than that on FN-treated L-SFE titanium disks. Compared to L-SFE titanium disks, integrin-β1, integrin-α5 and Rac-1 mRNA levels were significantly higher in MG-63 cells on FN-treated H-SFE after 3 h of culture. These findings suggest that the higher SFE of H-SFE compared to L-SFE titanium disks induced changes in the conformation of adsorbed FN that enhanced the osteogenic activity of MG-63 cells.

COVID-19: A systematic review and update on prevention, diagnosis, and treatment

Since the rapid onset of the COVID-19 or SARS-CoV-2 pandemic in the world in 2019, extensive studies have been conducted to unveil the behavior and emission pattern of the virus in order to determine the best ways to diagnosis of virus and thereof formulate effective drugs or vaccines to combat the disease. The emergence of novel diagnostic and therapeutic techniques considering the multiplicity of reports from one side and contradictions in assessments from the other side necessitates instantaneous updates on the progress of clinical investigations. There is also growing public anxiety from time to time mutation of COVID-19, as reflected in considerable mortality and transmission, respectively, from delta and Omicron variants. We comprehensively review and summarize different aspects of prevention, diagnosis, and treatment of COVID-19. First, biological characteristics of COVID-19 were explained from diagnosis standpoint. Thereafter, the preclinical animal models of COVID-19 were discussed to frame the symptoms and clinical effects of COVID-19 from patient to patient with treatment strategies and in-silico/computational biology. Finally, the opportunities and challenges of nanoscience/nanotechnology in identification, diagnosis, and treatment of COVID-19 were discussed. This review covers almost all SARS-CoV-2-related topics extensively to deepen the understanding of the latest achievements (last updated on January 11, 2022).

Synthesis of siRNA nanoparticles to silence plaque-destabilizing gene in atherosclerotic lesional macrophages

Macrophages in atherosclerotic lesions promote plaque progression and are an attractive therapeutic target in cardiovascular research. Here we present a protocol for synthesis of small interfering RNA (siRNA) nanoparticles (NP) that target lesional macrophages as a potential treatment for atherosclerosis. Ca²⁺/calmodulin-dependent protein kinase γ (CaMKIIγ) activity in macrophages of advanced human and mouse atherosclerotic plaques drives necrosis by downregulating the expression of the efferocytosis receptor MerTK. Therefore, selective inhibition of CaMKIIγ in lesional macrophages holds great promise for the treatment of advanced atherosclerosis. We recently developed a siRNA NP platform that can selectively silence CaMKIIγ in macrophages, resulting in increased plaque stability. We provide a detailed protocol for the synthesis of NP components, the preparation and characterization (physicochemical and in vitro) of siRNA NPs, and the evaluation of in vivo therapeutic effects of siRNA NPs and their biocompatibility in atherosclerotic mice. Our siRNA-loaded polymer-lipid hybrid NPs are constructed via a robust self-assembly method, exhibiting excellent in vivo features for systemic siRNA delivery. Following this protocol, it takes 3-5 d to prepare the siRNA NPs, 8-10 d to characterize the NPs and 4-5 weeks to evaluate their therapeutic effects in established atherosclerotic mice. By changing the RNA molecules loaded in the NPs, lesional macrophages can be targeted for the exploration and validation of new targets/pathways in atherosclerosis.

Therapeutic potentials of Aivlosin and/or Zinc Oxide nanoparticles against Mycoplasma gallisepticum and/or Ornithobacterium rhinotracheale with a special reference to the effect of Zinc Oxide nanoparticles on Aivlosin tissue residues: an in vivo approach

Respiratory diseases inflicted by Mycoplasma gallisepticum (MG) and Ornithobacterium rhinotracheale (ORT) cause severe economic losses and great burden to the poultry industry worldwide. Therefore, the current study was planned to assess the efficacy of aivlosin alone or in combination with zinc oxide nanoparticles (ZnO-NPs) in the treatment of experimental MG and/or ORT infections in broilers. Moreover, we also aimed to evaluate the role of ZnO-NPs on aivlosin residues in broiler tissues. A total of 1,440 Cobb chicks were allocated into 6 groups. At 14 d of age, chickens of groups 1 and 3 were experimentally infected with MG intratracheally and 6 d later, chickens of groups 2 and 3 were infected occulonasaly with ORT. Groups 1, 2, and 3 were divided into 4 subgroups; birds in subgroups 1, 2, and 3 were treated with aivlosin (A), ZnO-NPs (Z), and A/Z, respectively, while those in subgroups 4 was left without treatments. Moreover, groups 4 and 5 were kept noninfected and treated with aivlosin alone or in combination with ZnO-NPs, respectively. Finally, group 6 was kept as a negative control. The current results showed that the recovery from respiratory diseases caused by MG and/or ORT infections was most successful after treatment with A/Z in combination. Consequently, clinical signs, mortality rates, postmortem lesions of the respiratory organs, histopathological lesions of liver, trachea and lung and tracheal MG and ORT counts were significantly (P < 0.05) reduced following A/Z treatment. Taken together, high performance liquid chromatography analysis revealed that ZnO-NPs decreased the aivlosin residues in liver, muscle and skin of healthy and infected chickens. Based on these results, it could be concluded that aivlosin/ZnO-NPs therapy is a valuable approach for controlling MG and/or ORT infections in boilers.

Folate-Decorated Cross-Linked Cytochrome c Nanoparticles for Active Targeting of Non-Small Cell Lung Carcinoma (NSCLC)

The folate receptor alpha (FR), which is overexpressed in solid tumors including NSCLC, can be utilized for active tumor targeting to afford more effective cancer therapies. In this context, cytochrome c (Cyt c) has drawn attention to cancer research because it is non-toxic, yet, when delivered to the cytoplasm of cancer cells, can kill them by inducing apoptosis. Cyt c nanoparticles (NPs, 169 ± 9 nm) were obtained by solvent precipitation with acetonitrile, and stabilized by reversible homo-bifunctional crosslinking to accomplish a Cyt-c-based drug delivery system that combines stimulus-responsive release and active targeting. Cyt c was released under intracellular redox conditions, due to an S–S bond in the NPs linker, while NPs remained intact without any release under extracellular conditions. The NP surface was decorated with a hydrophilic folic acid–polyethylene glycol (FA–PEG) polymer for active targeting. The FA-decorated NPs specifically recognized and killed cancer cells (IC50 = 47.46 µg/mL) that overexpressed FR, but showed no toxicity against FR-negative cells. Confocal microscopy confirmed the preferential uptake and apoptosis induction of our NPs by FR-positive cancer cells. In vivo experiments using a Lewis lung carcinoma (LLC) mouse model showed visible NP accumulation within the tumor and inhibited the growth of LLC tumors.

Folate-Decorated Cross-Linked Cytochrome c Nanoparticles for Active Targeting of Non-Small Cell Lung Carcinoma (NSCLC)

The folate receptor alpha (FR), which is overexpressed in solid tumors including NSCLC, can be utilized for active tumor targeting to afford more effective cancer therapies. In this context, cytochrome c (Cyt c) has drawn attention to cancer research because it is non-toxic, yet, when delivered to the cytoplasm of cancer cells, can kill them by inducing apoptosis. Cyt c nanoparticles (NPs, 169 ± 9 nm) were obtained by solvent precipitation with acetonitrile, and stabilized by reversible homo-bifunctional crosslinking to accomplish a Cyt-c-based drug delivery system that combines stimulus-responsive release and active targeting. Cyt c was released under intracellular redox conditions, due to an S–S bond in the NPs linker, while NPs remained intact without any release under extracellular conditions. The NP surface was decorated with a hydrophilic folic acid–polyethylene glycol (FA–PEG) polymer for active targeting. The FA-decorated NPs specifically recognized and killed cancer cells (IC50 = 47.46 µg/mL) that overexpressed FR, but showed no toxicity against FR-negative cells. Confocal microscopy confirmed the preferential uptake and apoptosis induction of our NPs by FR-positive cancer cells. In vivo experiments using a Lewis lung carcinoma (LLC) mouse model showed visible NP accumulation within the tumor and inhibited the growth of LLC tumors.

Folate-Decorated Cross-Linked Cytochrome c Nanoparticles for Active Targeting of Non-Small Cell Lung Carcinoma (NSCLC)

The folate receptor alpha (FR), which is overexpressed in solid tumors including NSCLC, can be utilized for active tumor targeting to afford more effective cancer therapies. In this context, cytochrome c (Cyt c) has drawn attention to cancer research because it is non-toxic, yet, when delivered to the cytoplasm of cancer cells, can kill them by inducing apoptosis. Cyt c nanoparticles (NPs, 169 ± 9 nm) were obtained by solvent precipitation with acetonitrile, and stabilized by reversible homo-bifunctional crosslinking to accomplish a Cyt-c-based drug delivery system that combines stimulus-responsive release and active targeting. Cyt c was released under intracellular redox conditions, due to an S–S bond in the NPs linker, while NPs remained intact without any release under extracellular conditions. The NP surface was decorated with a hydrophilic folic acid–polyethylene glycol (FA–PEG) polymer for active targeting. The FA-decorated NPs specifically recognized and killed cancer cells (IC50 = 47.46 µg/mL) that overexpressed FR, but showed no toxicity against FR-negative cells. Confocal microscopy confirmed the preferential uptake and apoptosis induction of our NPs by FR-positive cancer cells. In vivo experiments using a Lewis lung carcinoma (LLC) mouse model showed visible NP accumulation within the tumor and inhibited the growth of LLC tumors.

Re-establishing the comprehension of phytomedicine and nanomedicine in inflammation-mediated cancer signaling

Recent mounting evidence has revealed extensive genetic heterogeneity within tumors that drive phenotypic variation affecting key cancer pathways, making cancer treatment extremely challenging. Diverse cancer types display resistance to treatment and show patterns of relapse following therapy. Therefore, efforts are required to address tumor heterogeneity by developing a broad-spectrum therapeutic approach that combines targeted therapies. Inflammation has been progressively documented as a vital factor in tumor advancement and has consequences in epigenetic variations that support tumor instigation, encouraging all the tumorigenesis phases. Increased DNA damage, disrupted DNA repair mechanisms, cellular proliferation, apoptosis, angiogenesis, and its incursion are a few pro-cancerous outcomes of chronic inflammation. A clear understanding of the cellular and molecular signaling mechanisms of tumor-endorsing inflammation is necessary for further expansion of anti-cancer therapeutics targeting the crosstalk between tumor development and inflammatory processes. Multiple inflammatory signaling pathways, such as the NF-κB signaling pathway, JAK-STAT signaling pathway, MAPK signaling, PI3K/AKT/mTOR signaling, Wnt signaling cascade, and TGF-β/Smad signaling, have been found to regulate inflammation, which can be modulated using various factors such as small molecule inhibitors, phytochemicals, recombinant cytokines, and nanoparticles in conjugation to phytochemicals to treat cancer. Researchers have identified multiple targets to specifically alter inflammation in cancer therapy to restrict malignant progression and improve the efficacy of cancer therapy. siRNA-and shRNA-loaded nanoparticles have been observed to downregulate STAT3 signaling pathways and have been employed in studies to target tumor malignancies. This review highlights the pathways involved in the interaction between tumor advancement and inflammatory progression, along with the novel approaches of nanotechnology-based drug delivery systems currently used to target inflammatory signaling pathways to combat cancer.

Lipid Composition of the Cell Membrane Outer Leaflet Regulates Endocytosis of Nanomaterials through Alterations in Scavenger Receptor Activity

Understanding the principles that guide the uptake of engineered nanomaterials (ENMs) by cells is of interest in biomedical and occupational health research. While evidence has started to accumulate on the role of membrane proteins in ENM uptake, the role of membrane lipid chemistry in regulating ENM endocytosis has remained largely unexplored. Here, we have addressed this issue by altering the plasma membrane lipid composition directly in live cells using a methyl-α-cyclodextrin (MαCD)-catalyzed lipid exchange method. Our observations, in an alveolar epithelial cell line and using silica nanoparticles, reveal that the lipid composition of the plasma membrane outer leaflet plays a significant role in ENM endocytosis and the intracellular fate of ENMs, by affecting nonspecific ENM diffusion into the cell, changing membrane fluidity, and altering the activity of scavenger receptors (SRs) involved in active endocytosis. These results have implications for understanding ENM uptake in different subsets of cells, depending on cell membrane lipid composition.

An Engineered Nanocomplex with Photodynamic and Photothermal Synergistic Properties for Cancer Treatment

Photodynamic therapy (PDT) and photothermal therapy (PTT) are promising therapeutic methods for cancer treatment; however, as single modality therapies, either PDT or PTT is still limited in its success rate. A dual application of both PDT and PTT, in a combined protocol, has gained immense interest. In this study, gold nanoparticles (AuNPs) were conjugated with a PDT agent, meso-tetrahydroxyphenylchlorin (mTHPC) photosensitizer, designed as nanotherapeutic agents that can activate a dual photodynamic/photothermal therapy in SH-SY5Y human neuroblastoma cells. The AuNP-mTHPC complex is biocompatible, soluble, and photostable. PDT efficiency is high because of immediate reactive oxygen species (ROS) production upon mTHPC activation by the 650-nm laser, which decreased mitochondrial membrane potential (^∆ψ_m). Likewise, the AuNP-mTHPC complex is used as a photoabsorbing (PTA) agent for PTT, due to efficient plasmon absorption and excellent photothermal conversion characteristics of AuNPs under laser irradiation at 532 nm. Under the laser irradiation of a PDT/PTT combination, a twofold phototoxicity outcome follows, compared to PDT-only or PTT-only treatment. This indicates that PDT and PTT have synergistic effects together as a combined therapeutic method. Our study aimed at applying the AuNP-mTHPC approach as a potential treatment of cancer in the biomedical field.

Shining Light on Polymeric Drug Nanocarriers with Fluorescence Correlation Spectroscopy

The use of nanoparticles as carriers is an extremely promising way for administration of therapeutic agents, such as drug molecules, proteins and nucleic acids. Such nanocarriers (NCs) can increase the solubility of hydrophobic compounds, protect their cargo from the environment, and if properly functionalized, deliver it to specific target cells and tissues. Polymer-based NCs are especially promising, because they offer high degree of versatility and tunability. However, in order to get a full advantage of this therapeutic approach and develop efficient delivery systems, a careful characterization of the NCs is needed. This Feature Article highlights the fluorescence correlation spectroscopy (FCS) technique as a powerful and versatile tool for NCs characterization at all stages of the drug delivery process. In particular, FCS can monitor and quantify the size of the NCs and the drug loading efficiency after preparation, the NCs stability and possible interactions with, e.g., plasma proteins in the blood stream and the kinetic of drug release in the cytoplasm of the target cells. This article is protected by copyright. All rights reserved.

SMA-BmobaSNO: an intelligent photoresponsive nitric oxide releasing polymer for drug nanoencapsulation and targeted delivery

Nitric oxide (NO) is an important biological signalling molecule that acts to vasodilate blood vessels and change the permeability of the blood vessel wall. Due to these cardiovascular actions, co-administering NO with a therapeutic could enhance drug uptake. However current NO donors are not suitable for targeted drug delivery as they systemically release NO. To overcome this limitation we report the development of a smart polymer, SMA-BmobaSNO, designed to release NO in response to a photostimulus. The polymer's NO releasing functionality is an S-nitrosothiol group that, at 10 mg ml^-1, is highly resistant to both thermal (t_1/216 d) and metabolic (t_1/232 h) decomposition, but rapidly brakes down under photoactivation (2700 W m^-2, halogen source) to release NO (t_1/225 min). Photoresponsive NO release from SMA-BmobaSNO was confirmed in a cardiovascular preparation, where irradiation resulted in a 12-fold decrease in vasorelaxation EC₅₀(from 5.2μM to 420 nM). To demonstrate the polymer's utility for drug delivery we then used SMA-BmobaSNO to fabricate a nanoparticle containing the probe Nile Red (NR). The resulting SMA-BmobaSNO-NR nanoparticle exhibited spherical morphology (180 nm diameter) and sustained NR release (≈20% over 5 d). Targeted delivery was characterised in an abdominal preparation, where photoactivation (450 W m^-2) caused localized increases in vasodilation and blood vessel permeability, resulting in a 3-fold increase in NR uptake into photoactivated tissue. Nanoparticles fabricated from SMA-BmobaSNO therefore display highly photoresponsive NO release and can apply the Trojan Horse paradigm by using endogenous NO signalling pathways to smuggle a therapeutic cargo into target tissue.

Designing Functional Bionanoconstructs for Effective In Vivo Targeting

The progress achieved over the last three decades in the field of bioconjugation has enabled the preparation of sophisticated nanomaterial–biomolecule conjugates, referred to herein as bionanoconstructs, for a multitude of applications including biosensing, diagnostics, and therapeutics. However, the development of bionanoconstructs for the active targeting of cells and cellular compartments, both in vitro and in vivo, is challenged by the lack of understanding of the mechanisms governing nanoscale recognition. In this review, we highlight fundamental obstacles in designing a successful bionanoconstruct, considering findings in the field of bionanointeractions. We argue that the biological recognition of bionanoconstructs is modulated not only by their molecular composition but also by the collective architecture presented upon their surface, and we discuss fundamental aspects of this surface architecture that are central to successful recognition, such as the mode of biomolecule conjugation and nanomaterial passivation. We also emphasize the need for thorough characterization of engineered bionanoconstructs and highlight the significance of population heterogeneity, which too presents a significant challenge in the interpretation of in vitro and in vivo results. Consideration of such issues together will better define the arena in which bioconjugation, in the future, will deliver functional and clinically relevant bionanoconstructs.

Proteins Adsorbing onto Surface-Modified Nanoparticles: Effect of Surface Curvature, pH, and the Interplay of Polymers and Proteins Acid-Base Equilibrium

Protein adsorption onto nanomaterials is a process of vital significance and it is commonly controlled by functionalizing their surface with polymers. The efficiency of this strategy depends on the design parameters of the nanoconstruct. Although significant amount of work has been carried out on planar surfaces modified with different types of polymers, studies investigating the role of surface curvature are not as abundant. Here, we present a comprehensive and systematic study of the protein adsorption process, analyzing the effect of curvature and morphology, the grafting of polymer mixtures, the type of monomer (neutral, acidic, basic), the proteins in solution, and the conditions of the solution. The theoretical approach we employed is based on a molecular theory that allows to explicitly consider the acid-base reactions of the amino acids in the proteins and the monomers on the surface. The calculations showed that surface curvature modulates the molecular organization in space, but key variables are the bulk pH and salt concentration (in the millimolar range). When grafting the NP with acidic or basic polymers, the surface coating could disfavor or promote adsorption, depending on the solution's conditions. When NPs are in contact with protein mixtures in solution, a nontrivial competitive adsorption process is observed. The calculations reflect the balance between molecular organization and chemical state of polymers and proteins, and how it is modulated by the curvature of the underlying surface.

Rational Designs at the Forefront of Mitochondria-Targeted Gene Delivery: Recent Progress and Future Perspectives

Mitochondria play an essential role in cellular metabolism and generate energy in cells. To support these functions, several proteins are encoded in the mitochondrial DNA (mtDNA). The mutation of mtDNA causes mitochondrial dysfunction and ultimately results in a variety of inherited diseases. To date, gene delivery systems targeting mitochondria have been developed to ameliorate mtDNA mutations. However, applications of these strategies in mitochondrial gene therapy are still being explored and optimized. Thus, from this perspective, we herein highlight recent mitochondria-targeting strategies for gene therapy and discuss future directions for effective mitochondria-targeted gene delivery.

Photothermal MnO2 nanoparticles boost chemo-photothermal therapy-induced immunogenic cell death in tumor immunotherapy

The induction of immunogenic cell death (ICD) is an attractive strategy for generating in situ autologous tumor cell-based vaccines and thus has great potential in cancer prevention and personalized immunotherapy. However, the effectiveness of ICD in tumor immunotherapy has been greatly limited, mainly by low induction efficiency and the immunosuppressive tumor microenvironment (TME). Herein, we report a new strategy for chemo-photothermal therapy-induced ICD by employing photothermal MnO₂ nanoparticles loaded with doxorubicin (DOX) in tumor immunotherapy to overcome the low efficiency of traditional ICD inducers and the immunosuppressive TME. Specifically, we prepared photothermal bovine serum albumin (BSA)-templated MnO₂ NPs (BSA/MnO₂ NPs) with good aqueous dispersibility and high biocompatibility through the direct reduction of KMnO₄ with BSA, and we then efficiently loaded DOX, an ICD inducer, onto the MnO₂ NPs through coordination (DOX-BSA/MnO₂ NPs). The DOX-BSA/MnO₂ NPs achieved high photothermal conversion efficiency, highly efficient tumor targeting, TME-responsive DOX release and modulation of the hypoxic TME. Notably, a marked in vivo synergistic therapeutic effect was achieved in a triple-negative breast carcinoma-bearing mouse model by combining chemo-photothermal therapy-induced ICD with amelioration of the immunosuppressive TME. Our research highlights the great promise of modulating the TME with photothermal MnO₂ nanosystems to enhance ICD-induced antitumor immunotherapy.

PSMA-Targeted Supramolecular Nanoparticles Prepared From Cucurbit[8]uril-Based Ternary Host–Guest Recognition for Prostate Cancer Therapy

Nanomedicines play an important role in cancer therapy; however, some drawbacks including unsatisfactory efficacy and side effects arising from indiscriminate drug release retard their clinical applications. Although functionalization of nanomedicines through covalent interactions can improve the pharmacokinetics and efficacy of the loaded drugs, complicated and tedious synthesis greatly limits the exploration of multifunctional nanoparticles. Herein, we utilize a supramolecular strategy to design a nanomedicine for targeted drug delivery through cucurbit[8]uril-based host–guest ternary complexation and successfully prepare prostate-specific membrane antigen (PSMA)-targeted supramolecular nanoparticles encapsulating doxorubicin (DOX). In vitro studies exhibit targeted modification via noncovalent enhance anticancer efficiency of DOX due to the increased cell uptake on account of receptor-mediated endocytosis. This design provides a new strategy for the development of sophisticated drug delivery systems and holds perspective potentials in precise cancer treatments.

Evaluation Avocado Soybean Unsaponifiables Loaded in Poly (lactic-co-glycolic) Acid/Avocado Soybean Unsaponifiables-Fibrin Nanoparticles Scaffold (New Delivery System) is an Effective Factor for Tissue Engineering

Background:

Growth factors and chemical stimulants have key role in cartilage tissue engineering, but these agents have unfavorable effects on cells. Avocado soybean unsaponifiables (ASU) has chondroprotective and anti-inflammatory effects. In this study, fibrin2nanoparticles (FNP)/ASU, as a new delivery system, with stem cells applied for cartilage tissue engineering in poly (lactic-co-glycolic) acid (PLGA) scaffold.

Materials and Methods:

FNP/ASU prepared by freeze milling and freeze drying. NFP/ASU was characterized by dynamic light scattering (DLS). PLGA-NFP/ASU scaffold was fabricated and assessed by scanning electron microscope (SEM). Human adipose-derived stem cells (hADSCs) were seeded on scaffold and induced for chondrogenesis. After 14 days, cell viability and gene/protein expression evaluated.

Results:

The results of DLS and SEM indicated that nanoparticles had high quality. The expression of type II collagen and SOX9 and aggrecan (ACAN) genes in differentiated cells in the presence of ASU was significantly increased compared with the control group (P and lt; 0.01), on the other hand, type I collagen expression was significantly decreased and western blot confirmed it.

Conclusions:

This study indicated FNP/ASU loaded in PLGA scaffold has excellent effect on chondrogenic differentiation of hADSCs and tissue engineering.

An NIR Discrete Metallacycle Constructed from Perylene Bisimide and Tetraphenylethylene Fluorophores for Imaging-Guided Cancer Radio-Chemotherapy

To promote the clinical theranostic performances of platinum-based anticancer drugs, imaging capability is urgently desired, and their chemotherapeutic efficacy needs to be upgraded. Herein, a theranostic metallacycle (M) is developed for imaging-guided cancer radio-chemotherapy using perylene bisimide fluorophore (PPy) and tetraphenylethylene-based di-Pt(II) organometallic precursor (TPE-Pt) as building blocks. The formation of this discrete supramolecular coordination complex facilitates the encapsulation of M by a glutathione (GSH)-responsive amphiphilic block copolymer to prepare M-loaded nanoparticles (MNPs). TPE-Pt acts as a chemotherapeutic drug and also an excellent radiosensitizer, thus incorporating radiotherapy into the nanomedicine to accelerate the therapeutic efficacy and overcome drug resistance. The NIR-emission of PPy is employed to detect the intracellular delivery and tissue distribution of MNPs in real time. In vitro and in vivo investigations demonstrate the excellent anticancer efficacy combining chemotherapy and radiotherapy; the administration of this nanomedicine effectively inhibits the tumor growth and greatly extends the survival rate of cisplatin-resistant A2780CIS-tumor-bearing mice. Guided by in vivo fluorescence imaging, radio-chemotherapy is precisely carried out, which facilitates boosting of the therapeutic outcomes and minimizing undesired side effects. The success of this theranostic system brings new hope to supramolecular nanomedicines for their potential clinical translations.