Virus-like Nanoparticles Research Articles

Migrated silicon dioxide nanoparticles activates the rice immunity for systemic resistance against two pathogens

Rice, the world's primary staple food, is under severe threat from several devastating diseases. To sustainably management rice diseases, developing safe, environmentally friendly alternatives urgently need to be developed. In this study, we synthesized two silicon dioxide nanoparticles, spherical mesoporous silica nanoparticles (MSNs) and virus-like mesoporous silica nanoparticles (VMSNs), and we performed a resistance assay on rice for two major diseases, bacterial blight caused by Xanthomonas oryzae pv. oryzae and sheath blight caused by Rhizoctonia solani. Compared to the control, the two nanoparticle treatments increased rice resistance, with VMSNs exhibiting the highest efficacy in controlling these two diseases, causing a shorter lesion length than those plants treated by MSNs. Coincidentally, the foliar application of VMSNs activates a higher expression level of several pathogenesis-related (PR) genes compared to those of MSNs and SiO2 treatment. By using fluorescein isothiocyanate (FITC)-labeled VMSNs (VMSNs-FITC) to soak the top expanded leaf tips or roots, we observed that the fluorescence of the nanoparticles firstly accumulated at the local site of the top leaves or roots, rapidly migrated to the hypocotyl of rice, and then redistributed sequentially from the bottom leaves to the upper leaves. Furthermore, the foliar or root application of VMSNs-FITC could trigger the local and systemic resistance to PXO99. Notably, no significant toxicity was observed on plants and mice after excessive foliar treatment or feeding tests, respectively. Overall, our research revealed that VMSNs are an effective, systemic, and safe nano-pesticides for controlling rice diseases. Boosting the immune responses may be associated with the transporting of nanoparticles.

Dismountable Protein Corona-Modified Virus-Like Manganese-Arsenic Nanomedicine Enables Safe and Targeted Delivery for Synergistic Arsenotherapy.

Arsenic agents have shown great potential in fighting leukemia, but are poorly known in treating solid tumors, mainly ascribing to the rapid clearance and low targeting ability. It is reported that morphology modulation can enhance the interaction between nanoparticles and cell membrane. Herein, a dismountable protein corona-modified virus-like manganese-arsenic nanomedicine (vMnAs@HR) is rationally proposed for realizing safe and targeted delivery and synergistic arsenotherapy. The virus-like manganese-arsenic nanoparticle (vMnAs) is constructed followed by modification of a temporary R848-loaded HDL (HR) protein corona. Upon intravenous injection, the HR protein corona is stable and actively targeted to tumor tissue by taking advantage of the interaction between HDL and its receptor SR-BI. Intriguingly, upon accumulated in the tumor, HR can be jettisoned and interacted with macrophages for proinflammatory phenotype modulation. The re-exposed vMnAs can efficiently enhance endocytosis by taking advantage of the rationally designed spiky morphology. Moreover, the released double-stranded DNA (dsDNA) and manganese ions during tumor cell apoptosis can cooperatively activate cyclic guanosine monophosphate adenosine monophosphate synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway of DCs for systematic immune activation. It is anticipated that this morphology-transformable nanomedicine can realize safe and efficient arsenic delivery for synergistic arsenotherapy.

Immunity and Protective Efficacy of a Plant-Based Tobacco Mosaic Virus-like Nanoparticle Vaccine against Influenza a Virus in Mice.

The rapid production of influenza vaccines is crucial to meet increasing pandemic response demands. Here, we developed plant-made vaccines comprising centralized consensus influenza hemagglutinin (HA-con) proteins (H1 and H3 subtypes) conjugated to a modified plant virus, tobacco mosaic virus (TMV) nanoparticle (TMV-HA-con). We compared immune responses and protective efficacy against historical H1 or H3 influenza A virus infections among TMV-HA-con, HA-con protein combined with AddaVax™ adjuvant, and whole-inactivated virus vaccine (Fluzone®). Immunogenicity studies demonstrated robust IgG, IgM, and IgA responses in the TMV-HA-con and HA-con protein vaccinated groups, with relatively low induction of interferon (IFN)-γ+ T-cell responses across all vaccinated groups. The TMV-HA-con and HA-con protein groups displayed partial protection (100% and 80% survival) with minimal weight loss following challenge with two H1N1 strains. The HA-con protein group exhibited 80% and 100% survival against two H3 strains, whereas the TMV-HA-con groups showed reduced protection (20% survival). The Fluzone® group conferred 20-100% survival against two H1N1 strains and one H3N1 strain, but did not protect against H3N2 infection. Our findings indicate that TMV-HA and HA-con protein vaccines with adjuvant induce protective immune responses against influenza A virus infections. Furthermore, our results underscore the potential of plant-based production using TMV-like nanoparticles for developing influenza A virus candidate vaccines.

High Cellular Internalization of Virus-Like Mesoporous Silica Nanoparticles Enhances Adaptive Antigen-Specific Immune Responses against Cancer.

Effective activation of an antigen-specific immune response hinges upon the intracellular delivery of cancer antigens to antigen-presenting cells (APCs), marking the initial stride in cancer vaccine development. Leveraging biomimetic topological morphology, we employed virus-like mesoporous silica nanoparticles (VMSNs) coloaded with antigens and toll-like receptor 9 (TLR9) agonists to craft a potent cancer vaccine. Our VMSNs could be efficiently internalized by APCs to a greater extent than their nonviral structured counterparts, thereby promoting the activation of APCs by upregulating the TLR9 pathway and cross-presenting ovalbumin (OVA) epitopes. In in vivo animal study, VMSN-based nanovaccines triggered substantial CD4+ and CD8+ lymphocyte populations in both lymph nodes and spleen while inducing the effector memory of adaptive T cells. Consequently, VMSN-based nanovaccines suppressed tumor progression and increased the survival rate of B16-OVA-bearing mice in both prophylactic and therapeutic studies. The combination of immune checkpoint blockade (ICB) with the VMSN-based nanovaccine has synergistic effects in significantly preventing tumor progression under therapeutic conditions. These findings highlight the potential of viral structure-mimicking mesoporous silica nanoparticles as promising candidates for antigen-delivering nanocarriers in vaccine development.

Synthesis of propargyl glycosides of Streptococcus pneumoniae serotypes 6A and 6B for glycoconjugate vaccines

We developed a method for making immune responses to bacterial glycans T cell-dependent, which involves attachment of short, synthetic glycans to a virus-like nanoparticle (VLP). This strategy enhances immune responses to glycans by facilitating cognate T cell help of B cells, leading to antibody class switching and affinity maturation yielding high-affinity, anti-glycan antibodies. This method requires synthesis of bacterial glycans as propargyl glycosides for covalent attachment to VLPs, and the resulting short linker between the VLP and glycan is important for optimal T cell receptor recognition. In this work, glycans that are part of the capsular polysaccharides (CPS) produced by Streptococcus pneumoniae serotypes Sp6A and Sp6B were synthesized as disaccharides and trisaccharides. The optimal glycan epitope for antibody binding to the CPS from these serotypes is unknown, and differing “frames” of disaccharides and trisaccharides were prepared to elucidate the optimal antigen for antibody binding.

Green Routes: Exploring Protein-Based Virus-like Nanoparticle Transport and Immune Activation in Nicotiana benthamiana for Biotechnological Applications.

Viral, bacterial, fungal, and nematode infections cause significant agricultural losses, with limited treatment options, necessitating novel approaches to enhance plant defense systems and protection against pathogens. Virus-like nanoparticles (VLPs), extensively used in animal and human therapies (e.g., vaccines and immune enhancers), hold potential for novel agricultural solutions and advancing plant nanotechnology. This study employed various methodologies, including VLP production, confocal microscopy, and real-time qPCR. Our findings demonstrated the presence of 30 nm Qβ-VLPs, fluorescently labeled, within the intercellular space of Nicotiana benthamiana leaves one hour post-infiltration. Furthermore, infiltration with Qβ-VLPs led to an upregulation of key defense genes (NbPR1a, NbPR5, NbNPR, NbERF1, NbMYC2, and NbLRR2) in treated plants. Using RT-qPCR, a significant increase in the relative expression levels of defense genes was observed, with sustained high levels of NbERF1 and NbLRR2 even after 24 h. These findings suggest that Qβ-VLPs effectively upregulate genes crucial for pathogen defense in N. benthamiana, initiating PAMP-triggered immunity and launching signaling cascades that enhance defense mechanisms. This innovative application of VLPs to activate plant defense programs advances plant nanobiotechnology, offering new agricultural solutions.

Macropinocytosis Is the Principal Uptake Mechanism of Antigen-Presenting Cells for Allergen-Specific Virus-like Nanoparticles.

Virus-like nanoparticles (VNP) are regarded as efficient vaccination platforms and have proven to be useful for the non-anaphylactogenic delivery of allergen-specific immunotherapy in preclinical models previously. Herein, we sought to determine the mode of VNP uptake by antigen presenting cells (APC). Accordingly, we screened a collection of substances known to inhibit different uptake pathways by APC. The human leukemia monocytic cell line THP-1 and the murine dendritic cell line DC 2.4 were examined for the uptake of fluorescently labelled VNP in the presence or absence of inhibitors. The inhibitory effect of candidate substances that blocked VNP uptake in APC lines was subsequently evaluated in studies with primary APC present in splenocyte and lung cell homogenates in vitro and upon intratracheal application of VNP in vivo. The uptake of allergen-specific VNP in vitro and in vivo was mainly observed by macrophages and CD103+ dendritic cells and was sensitive to inhibitors that block macropinocytosis, such as hyperosmolarity induced by sucrose or the polyphenol compound Rottlerin at low micromolar concentrations but not by other inhibitors. Also, T-cell proliferation induced by allergen-specific VNP was significantly reduced by both substances. In contrast, substances that stimulate macropinocytosis, such as Heparin and phorbol myristate acetate (PMA), increased VNP-uptake and may, thus, help modulate allergen-specific T-cell responses. We have identified macropinocytosis as the principal uptake mechanism of APC for allergen-specific VNP in vitro and in vivo, paving the way for further improvement of VNP-based therapies, especially those that can be used for tolerance induction in allergy, in the future.

Pathogen-Mimicking Nanoparticles Based on Rigid Nanomaterials as an Efficient Subunit Vaccine Delivery System for Intranasal Immunization.

Despite the safety profile of subunit vaccines, the inferior immunogenicity hinders their application in the nasal cavity. This study introduces a novel antigen delivery and adjuvant system utilizing mucoadhesive chitosan-catechol (Chic) on silica spiky nanoparticles (Ssp) to enhance immunity through multiple mechanisms. The Chic functionalizes the Ssp surface and incorporates with SARS-CoV-2 spike protein receptor-binding domain (RBD) and toll-like receptor (TLR)9 agonist unmethylated cytosine-guanine (CpG) motif, forming uniform virus-like nanoparticles (Ssp-Chic-RBD-CpG) via electrostatic and covalent interactions. Ssp-Chic-RBD-CpG, mimicking the morphology and function of inactive virions, effectively prolongs the retention time of RBD in the nasal mucosa by 3.92-fold compared to RBD alone, enhances the maturation of dendritic cells (DCs), and facilitates the antigen trafficking to the draining lymph nodes, which subsequently induces a stronger mucosal immunity. Mechanistically, the enhanced chemokine chemokine (C-C motif) ligand 20 (CCL20)-driven DCs recruitment and maturation by Ssp-Chic-RBD-CpG are evidenced by a cell co-culture model. In addition, the overexpression of TLR4/9 and activation of MYD88/NF-κB signaling pathway in activation of DCs are observed. Proof of principle is obtained for RBD, but similar delivery mechanisms can be applied in other protein-based subunit vaccines as well when intranasal administration is needed.

A highly effective ferritin-based divalent nanoparticle vaccine shields Syrian hamsters against lethal Nipah virus.

The Nipah virus (NiV), a highly deadly bat-borne paramyxovirus, poses a substantial threat due to recurrent outbreaks in specific regions, causing severe respiratory and neurological diseases with high morbidity. Two distinct strains, NiV-Malaysia (NiV-M) and NiV-Bangladesh (NiV-B), contribute to outbreaks in different geographical areas. Currently, there are no commercially licensed vaccines or drugs available for prevention or treatment. In response to this urgent need for protection against NiV and related henipaviruses infections, we developed a novel homotypic virus-like nanoparticle (VLP) vaccine co-displaying NiV attachment glycoproteins (G) from both strains, utilizing the self-assembling properties of ferritin protein. In comparison to the NiV G subunit vaccine, our nanoparticle vaccine elicited significantly higher levels of neutralizing antibodies and provided complete protection against a lethal challenge with NiV infection in Syrian hamsters. Remarkably, the nanoparticle vaccine stimulated the production of antibodies that exhibited superior cross-reactivity to homologous or heterologous henipavirus. These findings underscore the potential utility of ferritin-based nanoparticle vaccines in providing both broad-spectrum and long-term protection against NiV and emerging zoonotic henipaviruses challenges.

3D positional metrology of a virus-like nanoparticle with topologically structured light

Locating and identifying viruses in in vitro optical measurements is desirable for disease control; however, the sub-diffraction-limit dimensions and low refractive index contrast of viruses make this challenging. Here, we introduce a 3D positional nanometrology for a virus-like 100 nm polystyrene sphere that can reveal the position of the nanoparticle with deeply sub-wavelength accuracy using topologically structured light illumination and machine learning. Scattering of topologically structured light is highly sensitive to the position of a nano-object. Exploiting this, our experiments demonstrate deeply sub-wavelength (λ) precision reaching 5 nm (λ/91). Our findings indicate a route toward label-free in vitro nanometrology of viruses and similar nano-objects with precision far beyond the Abbe–Rayleigh diffraction limit.

Engineered nanoparticles promote cardiac tropism of AAV vectors

Cardiac muscle targeting is a notoriously difficult task. Although various nanoparticle (NP) and adeno-associated viral (AAV) strategies with heart tissue tropism have been developed, their performance remains suboptimal. Significant off-target accumulation of i.v.-delivered pharmacotherapies has thwarted development of disease-modifying cardiac treatments, such as gene transfer and gene editing, that may address both rare and highly prevalent cardiomyopathies and their complications. Here, we present an intriguing discovery: cargo-less, safe poly (lactic-co-glycolic acid) particles that drastically improve heart delivery of AAVs and NPs. Our lead formulation is referred to as ePL (enhancer polymer). We show that ePL increases selectivity of AAVs and virus-like NPs (VLNPs) to the heart and de-targets them from the liver. Serotypes known to have high (AAVrh.74) and low (AAV1) heart tissue tropisms were tested with and without ePL. We demonstrate up to an order of magnitude increase in heart-to-liver accumulation ratios in ePL-injected mice. We also show that ePL exhibits AAV/NP-independent mechanisms of action, increasing glucose uptake in the heart, increasing cardiac protein glycosylation, reducing AAV neutralizing antibodies, and delaying blood clearance of AAV/NPs. Current approaches utilizing AAVs or NPs are fraught with challenges related to the low transduction of cardiomyocytes and life-threatening immune responses; our study introduces an exciting possibility to direct these modalities to the heart at reduced i.v. doses and, thus, has an unprecedented impact on drug delivery and gene therapy. Based on our current data, the ePL system is potentially compatible with any therapeutic modality, opening a possibility of cardiac targeting with numerous pharmacological approaches.Graphical

Immunogenicity of novel vB_EcoS_NBD2 bacteriophage-originated nanotubes as a carrier for peptide-based vaccines

Non-infectious virus-like nanoparticles mimic native virus structures and can be modified by inserting foreign protein fragments, making them immunogenic tools for antigen presentation. This study investigated, for the first time, the immunogenicity of long and flexible polytubes formed by yeast-expressed tail tube protein gp39 of bacteriophage vB_EcoS_NBD2 and evaluated their ability to elicit an immune response against the inserted protein fragments. Protein gp39-based polytubes induced humoral immune response in mice, even without the use of adjuvant. Bioinformatics analysis guided the selection of protein fragments from Acinetobacter baumannii for insertion into the C-terminus of gp39. Chimeric polytubes, displaying 28-amino acid long OmpA protein fragment, induced IgG response against OmpA protein fragment in immunized mice. These polytubes demonstrated their effectiveness both as antigen carrier and an adjuvant, when the OmpA fragments were either displayed on chimeric polytubes or used alongside with the unmodified polytubes. Our findings expand the potential applications of long and flexible polytubes, contributing to the development of novel antigen carriers with improved immunogenicity and antigen presentation capabilities.

Inorganic virus-like nanoparticles for biomedical applications: a minireview

Inorganic virus-like nanoparticles for biomedical applications: a minireview

Engineering Assembly of Plasmonic Virus-Like Gold SERS Nanoprobe Guided by Intelligent Dual-Machine Nanodevice for High-Performance Analysis of Tetracycline.

Accurate detection of trace tetracyclines (TCs) in complex matrices is of great significance for food and environmental safety monitoring. However, traditional recognition and amplification tools exhibit poor specificity and sensitivity. Herein, a novel dual-machine linkage nanodevice (DMLD) is proposed for the first time to achieve high-performance analysis of TC, with a padlock aptamer component as the initiation command center, nucleic acid-encoded multispike virus-like Au nanoparticles (nMVANs) as the signal indicator, and cascade walkers circuit as the processor. The existence of spike vertices and interspike nanogaps in MVANs enables intense electromagnetic near-field focusing, allowing distinct surface-enhanced Raman scattering (SERS) activity. Moreover, through the sequential activation between multistage walker catalytic circuits, the DLMD system converts the limited TC recognition into massive engineering assemblies of SERS probes guided by DNA amplicons, resulting in synergistic enhancement of bulk plasmonic hotspot entities. The continuously guaranteed target recognition and progressively promoted signal enhancement ensure highly specific amplification analysis of TC, with a detection limit as low as 7.94 × 10-16g mL-1. Furthermore, the reliable recoveries in real samples confirm the practicability of the proposed sensing platform, highlighting the enormous potential of intelligent nanomachines for analyzing the trace hazards in the environment and food.

Virus-like nanoparticle vaccines for inducing long-lasting immunity against infectious diseases.

Virus-like nanoparticle vaccines for inducing long-lasting immunity against infectious diseases.

Preparation of viromimetic rod-like nanoparticle vaccines (RLNVax) and study of their humoral immune activation efficacy.

Virus-like nanoparticle vaccines can efficiently activate the humoral immune response by cross-linking B cell receptors with their surface multivalent antigen arrays. This structurally dependent mechanism makes it crucial to regulate and optimize structural parameters to enhance the efficacy of nanoparticle vaccines. In this study, we prepared nanoparticle vaccines with different aspect ratios by chemically modifying antigen proteins onto the surfaces of poly(amino acid) nanoparticles of various shapes (spherical, ellipsoidal, and rod-like). This allowed us to investigate the impact of structural anisotropy on the humoral immune activation efficacy of nanoparticle vaccines. Furthermore, the end-group molecules of poly(amino acid) materials possess aggregation-induced emission (AIE) properties, which facilitate monitoring the dynamics of nano-assemblies within the body. Results showed that rod-like nanoparticle vaccines (RLNVax) with a higher aspect ratio (AR = 5) exhibited greater lymph node draining efficiency and could elicit more effective B cell activation compared to conventional isotropic spherical nanoparticle vaccines. In a murine subcutaneous immunization model using ovalbumin (OVA) as a model antigen, RLNVax elicited antigen-specific antibody titers that were about 64 times and 4.6 times higher than those induced by free antigen proteins and spherical nanoparticle vaccines, respectively. Additionally, when combined with an aluminum adjuvant, antibody titers elicited by RLNVax were further enhanced by 4-fold. These findings indicate that the anisotropic rod-like structure is advantageous for improving the humoral immune activation efficacy of nanoparticle vaccines, providing significant insights for the design and optimization of next-generation nanoparticle vaccines.

Polymer-based synthetic oncolytic virus-like nanoparticles for cancer immunotherapy

Polymer-based synthetic oncolytic virus-like nanoparticles for cancer immunotherapy

A blocking ELISA based on virus-like nanoparticles chimerized with an antigenic epitope of ASFV P54 for detecting ASFV antibodies

African swine fever virus (ASFV) is a highly lethal pathogen of domestic and wild pigs. Due to no vaccines or drugs available, early accurate diagnosis and eradication of infected animals are the most important measures for ASFV prevention and control. Bluetongue virus (BTV) core-like particles (CLPs) are non-infectious hollow nanoparticles assembled from the BTV VP3 and VP7 proteins, which could be used as a platform for presenting foreign epitopes. In this study, the secondary structure of BTV VP7 protein was analyzed and predicted using the IEDB Analysis resource. Based on the prediction results of the VP7 protein, the chimeric CLPs with an ASFV P54 epitope were successfully prepared through the BAC-to-BAC baculovirus expression system and sucrose gradient centrifugation. Based on the chimeric CLPs and mAb 2E4 against AFSV P54 epitope, a blocking ELISA for detecting AFSV antibodies was established, and its reaction conditions were optimized. Through comprehensive evaluation of the method, the results showed the chimeric CLPs-based blocking ELISA displayed the best detection performance, with an AUC of 0.9961, a sensitivity of 97.65%, and a specificity of 95.24% in ROC analysis. Compared with western blot and a commercial c-ELISA for detecting anti-ASFV antibodies, this method had an excellent agreement of 96.35% (kappa value = 0.911) and 97.76% (kappa value = 0.946) with the other tests, respectively. This ELISA also had high repeatability, with CV < 10%, and no cross-reaction with the serum antibodies against other swine viruses or Orbivirus. In brief, this was the first report on developing a blocking ELISA based on virus-like nanoparticles chimerized with an antigenic epitope of ASFV P54 for serological diagnosis of ASFV.

Virus-like Iron-Gold Heterogeneous Nanoparticles for Drug Target Screening.

Drug-target recognition has great impacts on revealing mechanisms of pharmacological activities, especially drug resistance and off-target effects. In recent years, chemoproteomics has been widely used for drug target screening and discovery due to its high-throughput, high accuracy, and sensitivity. However, there still remain challenges on how to efficiently and unambiguously track target proteins from complex biological matrices. Herein, we report a drug target screening method based on virus-like iron-gold heterogeneous nanoparticles (Au@Fe3O4 NPs). The unique structure of Au@Fe3O4 NPs not only maintains the magnetism of Fe3O4 NPs to facilitate protein enrichment and purification, but also increases drug modification by introducing more active sites on the surface of Au NPs. After coincubating the drug modified NPs with the cell lysate, the high loading of drug on the surface of Au@Fe3O4 NPs was beneficial for capturing target proteins with low abundance. This well-designed heterogeneous nanomaterial provides a novel strategy for improving the efficiency and accuracy of affinity-based proteomics.

Virus-like Silica Nanoparticles Improve Permeability of Macromolecules across the Blood-Brain Barrier In Vitro.

The presence of the blood-brain barrier (BBB) limits the delivery of therapies into the brain. There has been significant interest in overcoming the BBB for the effective delivery of therapies to the brain. Inorganic nanomaterials, especially silica nanoparticles with varying surface chemistry and surface topology, have been recently used as permeation enhancers for oral protein delivery. In this context, nanoparticles with varying sizes and surface chemistries have been employed to overcome this barrier; however, there is no report examining the effect of nanoscale roughness on BBB permeability. This paper reports the influence of nanoscale surface roughness on the integrity and permeability of the BBB in vitro, using smooth surface Stöber silica nanoparticles (60 nm) compared to rough surface virus-like silica nanoparticles (VSNP, 60 nm). Our findings reveal that VSNP (1 mg/mL) with virus-mimicking-topology spiky surface have a greater effect on transiently opening endothelial tight junctions of the BBB than the same dose of Stöber silica nanoparticles (1 mg/mL) by increasing the FITC-Dextran (70 kDa) permeability 1.9-fold and by decreasing the trans-endothelial electrical resistance (TEER) by 2.7-fold. This proof-of-concept research paves the way for future studies to develop next-generation tailored surface-modified silica nanoparticles, enabling safe and efficient macromolecule transport across the BBB.