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Nature Nanotechnology Jul 2019Large doses of chemical pesticides are required to achieve effective concentrations in the rhizosphere, which results in the accumulation of harmful residues. Precision...
Large doses of chemical pesticides are required to achieve effective concentrations in the rhizosphere, which results in the accumulation of harmful residues. Precision farming is needed to improve the efficacy of pesticides, but also to avoid environmental pollution, and slow-release formulations based on nanoparticles offer one solution. Here, we tested the mobility of synthetic and virus-based model nanopesticides by combining soil column experiments with computational modelling. We found that the tobacco mild green mosaic virus and cowpea mosaic virus penetrate soil to a depth of at least 30 cm, and could therefore deliver nematicides to the rhizosphere, whereas the Physalis mosaic virus remains in the first 4 cm of soil and would be more useful for the delivery of herbicides. Our experiments confirm that plant viruses are superior to synthetic mesoporous silica nanoparticles and poly(lactic-co-glycolic acid) for the delivery and controlled release of pesticides, and could be developed as the next generation of pesticide delivery systems.
Topics: Agriculture; Comovirus; Delayed-Action Preparations; Mosaic Viruses; Nanoparticles; Pesticides; Soil; Soil Microbiology; Tobacco Mosaic Virus; Tymovirus
PubMed: 31110265
DOI: 10.1038/s41565-019-0453-7 -
Nucleic Acids Research Sep 1984The amino acid sequences deduced from the nucleic acid sequences of several animal picornaviruses and cowpea mosaic virus (CPMV), a plant virus, were compared. Good... (Comparative Study)
Comparative Study
The amino acid sequences deduced from the nucleic acid sequences of several animal picornaviruses and cowpea mosaic virus (CPMV), a plant virus, were compared. Good homology was found between CPMV and the picornaviruses in the region of the picornavirus 2C (P2-X protein), VPg, 3C pro (proteinase) and 3D pol (RNA polymerase) regions. The CPMV B genome was found to have a similar gene organization to the picornaviruses. A comparison of the 3C pro (proteinase) regions of all of the available picornavirus sequences and CPMV allowed us to identify residues that are completely conserved; of these only two residues, Cys-147 and His-161 (poliovirus proteinase) could be the reactive residues of the active site of a proteinase with analogous mechanism to a known proteinase. We conclude that the proteinases encoded by these viruses are probably cysteine proteinases, mechanistically related, but not homologous to papain.
Topics: Amino Acid Sequence; Base Sequence; Biological Evolution; DNA-Directed RNA Polymerases; Genes; Genes, Viral; Mosaic Viruses; Peptide Hydrolases; Picornaviridae; Species Specificity; Viral Proteins
PubMed: 6384934
DOI: 10.1093/nar/12.18.7251 -
Virology Jan 2014Due to the nanoscale size and the strictly controlled and consistent morphologies of viruses, there has been a recent interest in utilizing them in nanotechnology. The... (Review)
Review
Due to the nanoscale size and the strictly controlled and consistent morphologies of viruses, there has been a recent interest in utilizing them in nanotechnology. The structure, surface chemistries and physical properties of many viruses have been well elucidated, which have allowed identification of regions of their capsids which can be modified either chemically or genetically for nanotechnological uses. In this review we focus on the use of such modifications for the functionalization and production of viruses and empty viral capsids that can be readily decorated with metals in a highly tuned manner. In particular, we discuss the use of two plant viruses (Cowpea mosaic virus and Tobacco mosaic virus) which have been extensively used for production of novel metal nanoparticles (<100nm), composites and building blocks for 2D and 3D materials, and illustrate their applications.
Topics: Comovirus; Defective Viruses; Nanostructures; Nanotechnology; Tobacco Mosaic Virus
PubMed: 24418546
DOI: 10.1016/j.virol.2013.11.002 -
Journal of Visualized Experiments : JoVE Nov 2012The use of nanomaterials has the potential to revolutionize materials science and medicine. Currently, a number of different nanoparticles are being investigated for...
The use of nanomaterials has the potential to revolutionize materials science and medicine. Currently, a number of different nanoparticles are being investigated for applications in imaging and therapy. Viral nanoparticles (VNPs) derived from plants can be regarded as self-assembled bionanomaterials with defined sizes and shapes. Plant viruses under investigation in the Steinmetz lab include icosahedral particles formed by Cowpea mosaic virus (CPMV) and Brome mosaic virus (BMV), both of which are 30 nm in diameter. We are also developing rod-shaped and filamentous structures derived from the following plant viruses: Tobacco mosaic virus (TMV), which forms rigid rods with dimensions of 300 nm by 18 nm, and Potato virus X (PVX), which form filamentous particles 515 nm in length and 13 nm in width (the reader is referred to refs. (1) and (2) for further information on VNPs). From a materials scientist's point of view, VNPs are attractive building blocks for several reasons: the particles are monodisperse, can be produced with ease on large scale in planta, are exceptionally stable, and biocompatible. Also, VNPs are "programmable" units, which can be specifically engineered using genetic modification or chemical bioconjugation methods. The structure of VNPs is known to atomic resolution, and modifications can be carried out with spatial precision at the atomic level, a level of control that cannot be achieved using synthetic nanomaterials with current state-of-the-art technologies. In this paper, we describe the propagation of CPMV, PVX, TMV, and BMV in Vigna ungiuculata and Nicotiana benthamiana plants. Extraction and purification protocols for each VNP are given. Methods for characterization of purified and chemically-labeled VNPs are described. In this study, we focus on chemical labeling of VNPs with fluorophores (e.g. Alexa Fluor 647) and polyethylene glycol (PEG). The dyes facilitate tracking and detection of the VNPs, and PEG reduces immunogenicity of the proteinaceous nanoparticles while enhancing their pharmacokinetics. We demonstrate tumor homing of PEGylated VNPs using a mouse xenograft tumor model. A combination of fluorescence imaging of tissues ex vivo using Maestro Imaging System, fluorescence quantification in homogenized tissues, and confocal microscopy is used to study biodistribution. VNPs are cleared via the reticuloendothelial system (RES); tumor homing is achieved passively via the enhanced permeability and retention (EPR) effect. The VNP nanotechnology is a powerful plug-and-play technology to image and treat sites of disease in vivo. We are further developing VNPs to carry drug cargos and clinically-relevant imaging moieties, as well as tissue-specific ligands to target molecular receptors overexpressed in cancer and cardiovascular disease.
Topics: Animals; Bromovirus; Colonic Neoplasms; Comovirus; Fabaceae; HT29 Cells; Humans; Mice; Mice, Nude; Microscopy, Electron, Transmission; Nanoparticles; Plant Viruses; Potexvirus; Spectrophotometry, Ultraviolet; Nicotiana; Tobacco Mosaic Virus
PubMed: 23183850
DOI: 10.3791/4352 -
Advanced Science (Weinheim,... Nov 2021Prognosis and treatment of metastatic cancer continues to be one of the most difficult and challenging areas of oncology. Treatment usually consists of...
Prognosis and treatment of metastatic cancer continues to be one of the most difficult and challenging areas of oncology. Treatment usually consists of chemotherapeutics, which may be ineffective due to drug resistance, adverse effects, and dose-limiting toxicity. Therefore, novel approaches such as immunotherapy have been investigated to improve patient outcomes and minimize side effects. S100A9 is a calcium-binding protein implicated in tumor metastasis, progression, and aggressiveness that modulates the tumor microenvironment into an immunosuppressive state. S100A9 is expressed in and secreted by immune cells in the pre-metastatic niche, as well as, post-tumor development, therefore making it a suitable targeted for prophylaxis and therapy. In previous work, it is demonstrated that cowpea mosaic virus (CPMV) acts as an adjuvant when administered intratumorally. Here, it is demonstrated that systemically administered, S100A9-targeted CPMV homes to the lungs leading to recruitment of innate immune cells. This approach is efficacious both prophylactically and therapeutically against lung metastasis from melanoma and breast cancer. The current research will facilitate and accelerate the development of next-generation targeted immunotherapies administered as prophylaxis, that is, after surgery of a primary breast tumor to prevent outgrowth of metastasis, as well as, therapy to treat established metastatic disease.
Topics: Animals; Breast Neoplasms; Calgranulin B; Cell Line, Tumor; Comovirus; Female; Humans; Immunotherapy; Lung Neoplasms; Macrophages; Melanoma, Experimental; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Nanoparticles; Peptides; Pre-Exposure Prophylaxis; Survival Rate
PubMed: 34519180
DOI: 10.1002/advs.202101796 -
International Journal of Molecular... Dec 2023CBP60b (CALMODULIN-BINDING PROTEIN 60b) is a member of the CBP60 transcription factor family. In Arabidopsis, CBP60b not only regulates growth and development but also...
CBP60b (CALMODULIN-BINDING PROTEIN 60b) is a member of the CBP60 transcription factor family. In Arabidopsis, CBP60b not only regulates growth and development but also activates the transcriptions in immune responses. So far, CBP60b has only been studied extensively in the model plant Arabidopsis and rarely in crops. In this study, (BPMV)-mediated gene silencing (BPMV-VIGS) was used to silence in soybean plants. The silencing of resulted in typical autoimmunity, such as dwarfism and enhanced resistance to both (SMV) and pv. glycinea (). To further understand the roles of CBP60b in immunity and circumvent the recalcitrance of soybean transformation, we generated transgenic tobacco lines that overexpress . The overexpression of also resulted in autoimmunity, including spontaneous cell death on the leaves, highly induced expression of PATHOGENESIS-RELATED () genes, significantly elevated accumulation of defense hormone salicylic acid (SA), and significantly enhanced resistance to DC3000 ( pv. tomato DC3000). The transient coexpression of a luciferase reporter gene driven by the promoter of soybean SYSTEMIC ACQUIRED RESISTANCE DEFICIENT 1 () (), together with driven by the 35S promoter, led to the activation of the LUC reporter gene, suggesting that CBP60b.1 could bind to the core (A/T)AATT motifs within the promoter region of and, thus, activate the expression of the LUC reporter. Taken together, our results indicate that CBP60b.1/2 play both positive and negative regulatory roles in immune responses. These results also suggest that the function of CBP60b is conserved across plant species.
Topics: Arabidopsis; Autoimmunity; Calmodulin-Binding Proteins; Glycine max; Plant Immunity; Comovirus
PubMed: 38203547
DOI: 10.3390/ijms25010378 -
Journal For Immunotherapy of Cancer Mar 2022Inflammatory mammary cancer (IMC), the counterpart of human inflammatory breast cancer (IBC), is the deadliest form of canine mammary tumors. IMC patients lack specific...
BACKGROUND
Inflammatory mammary cancer (IMC), the counterpart of human inflammatory breast cancer (IBC), is the deadliest form of canine mammary tumors. IMC patients lack specific therapy and have poor outcomes. This proof-of-principle preclinical study evaluated the efficacy, safety, and effect on survival of neoadjuvant intratumoral (in situ) empty cowpea mosaic virus (eCPMV) immunotherapy in companion dogs diagnosed with IMC.
METHODS
Ten IMC-bearing dogs were enrolled in the study. Five dogs received medical therapy, and five received weekly neoadjuvant in situ eCPMV immunotherapy (0.2-0.4 mg per injection) and medical therapy after the second eCPMV injection. Efficacy was evaluated by reduction of tumor growth; safety by hematological and biochemistry changes in blood and plasma; and patient outcome by survival analysis. eCPMV-induced immune changes in blood cells were analyzed by flow cytometry; changes in the tumor microenvironment were evaluated by CD3 (T lymphocytes), CD20 (B lymphocytes), FoxP3 (Treg lymphocytes), myeloperoxidase (MPO; neutrophils), Ki-67 (proliferation index, PI; tumor cell proliferation), and Cleaved Caspase-3 (CC-3; apoptosis) immunohistochemistry.
RESULTS
Two neoadjuvant in situ eCPMV injections resulted in tumor shrinkage in all patients by day 14 without systemic adverse events. Although surgery for IMC is generally not an option, reduction in tumor size allowed surgery in two IMC patients. In peripheral blood, in situ eCPMV immunotherapy was associated with a significant decrease of Treg/CD8 ratio and changes in CD8Granzyme B T cells, which behave as a lagging predictive biomarker. In the TME, higher neutrophilic infiltration and MPO expression, lower tumor Ki-67 PI, increase in CD3 lymphocytes, decrease in FoxP3/CD3 ratio (p0.04 for all comparisons), and no changes in CC-3 immunostainings were observed in post-treatment tumor tissues when compared with pretreatment tumor samples. eCPMV-treated IMC patients had a statistically significant (p=0.033) improved overall survival than patients treated with medical therapy.
CONCLUSIONS
Neoadjuvant in situ eCPMV immunotherapy demonstrated anti-tumor efficacy and improved survival in IMC patients without systemic adverse effects. eCPMV-induced changes in immune cells point to neutrophils as a driver of immune response. Neoadjuvant in situ eCPMV immunotherapy could be a groundbreaking immunotherapy for canine IMC and a potential future immunotherapy for human IBC patients.
Topics: Animals; Comovirus; Dogs; Forkhead Transcription Factors; Humans; Inflammatory Breast Neoplasms; Ki-67 Antigen; Neoadjuvant Therapy; Neoplasms; Tumor Microenvironment; Vaccination
PubMed: 35277459
DOI: 10.1136/jitc-2021-004044 -
Viruses Jan 2024Here, we review the research undertaken since the 1950s in Australia's grain cropping regions on seed-borne virus diseases of cool-season pulses caused by alfalfa mosaic... (Review)
Review
Here, we review the research undertaken since the 1950s in Australia's grain cropping regions on seed-borne virus diseases of cool-season pulses caused by alfalfa mosaic virus (AMV) and cucumber mosaic virus (CMV). We present brief background information about the continent's pulse industry, virus epidemiology, management principles and future threats to virus disease management. We then take a historical approach towards all past investigations with these two seed-borne pulse viruses in the principal cool-season pulse crops grown: chickpea, faba bean, field pea, lentil, narrow-leafed lupin and white lupin. With each pathosystem, the main focus is on its biology, epidemiology and management, placing particular emphasis on describing field and glasshouse experimentation that enabled the development of effective phytosanitary, cultural and host resistance control strategies. Past Australian cool-season pulse investigations with AMV and CMV in the less commonly grown species (vetches, narbon bean, fenugreek, yellow and pearl lupin, grass pea and other species) and those with the five less important seed-borne pulse viruses also present (broad bean stain virus, broad bean true mosaic virus, broad bean wilt virus, cowpea mild mottle virus and peanut mottle virus) are also summarized. The need for future research is emphasized, and recommendations are made regarding what is required.
Topics: Medicago sativa; Cucumovirus; Seasons; Australia; Seeds; Alfalfa mosaic virus; Comovirus; Cytomegalovirus Infections
PubMed: 38257844
DOI: 10.3390/v16010144 -
Molecular Pharmaceutics Feb 2022Viral immunotherapies are being recognized in cancer treatment, with several currently approved or undergoing clinical testing. While contemporary approaches have...
Viral immunotherapies are being recognized in cancer treatment, with several currently approved or undergoing clinical testing. While contemporary approaches have focused on oncolytic viral therapies, our efforts center on the development of plant virus-based cancer immunotherapies. In a previous work, we demonstrated the potent efficacy of the cowpea mosaic virus (CPMV), a plant virus that does not replicate in animals, applied as an in situ vaccine. CPMV is an immunostimulatory drug candidate, and intratumoral administration remodels the tumor microenvironment leading to activation of local and systemic antitumor immunity. Efficacy has been demonstrated in multiple tumor mouse models and canine cancer patients. As wild-type CPMV is infectious toward various legumes and because shedding of infectious virus from patients may be an agricultural concern, we developed UV-inactivated CPMV (termed inCPMV) which is not infectious toward plants. We report that as a monotherapy, wild-type CPMV outperforms inCPMV in mouse models of dermal melanoma or disseminated colon cancer. Efficacy of inCPMV is less than that of CPMV and similar to that of RNA-free CPMV. Immunological investigation using knockout mice shows that inCPMV does not signal through TLR7 (toll-like receptor); structure-function studies indicate that the RNA is highly cross-linked and therefore unable to activate TLR7. Wild-type CPMV signals through TLR2, -4, and -7, whereas inCPMV more closely resembles RNA-free CPMV which signals through TLR2 and -4 only. The structural features of inCPMV explain the increased potency of wild-type CPMV through the triple pronged TLR activation. Strikingly, when inCPMV is used in combination with an anti-OX40 agonist antibody (administered systemically), exceptional efficacy was demonstrated in a bilateral B16F10 dermal melanoma model. Combination therapy, with in situ vaccination applied only into the primary tumor, controlled the progression of the secondary, untreated tumors, with 10 out of 14 animals surviving for at least 100 days post tumor challenge without development of recurrence or metastatic disease. This study highlights the potential of inCPMV as an in situ vaccine candidate and demonstrates the power of combined immunotherapy approaches. Strategic immunocombination therapies are the formula for success, and the combination of in situ vaccination strategies along with therapeutic antibodies targeting the cancer immunity cycle is a particularly powerful approach.
Topics: Animals; Cancer Vaccines; Comovirus; Disease Models, Animal; Dogs; Humans; Immunotherapy; Melanoma; Mice; Tumor Microenvironment
PubMed: 34978197
DOI: 10.1021/acs.molpharmaceut.1c00681 -
Biomaterials Aug 2021Cowpea mosaic virus (CPMV), a non-enveloped plant virus, and empty CPMV (eCPMV), a virus-like particle (VLP) composed of CPMV capsid without nucleic acids, are potent in...
Cowpea mosaic virus (CPMV), a non-enveloped plant virus, and empty CPMV (eCPMV), a virus-like particle (VLP) composed of CPMV capsid without nucleic acids, are potent in situ cancer vaccines when administered intratumorally (I.T.). However, it is unclear how immune cells recognize these nanoparticles and why they are immunogenic, which was investigated in this study. CPMV generated stronger selective induction of cytokines and chemokines in naïve mouse splenocytes and exhibited more potent anti-tumor efficacy than eCPMV. MyD88 is required for both CPMV- and eCPMV-elicited immune responses. Screening with human embryonic kidney (HEK)-293 cell toll-like receptor (TLR) reporter assays along with experiments in corresponding TLR-/- mice indicated CPMV and eCPMV capsids are recognized by MyD88-dependent TLR2 and TLR4. CPMV, but not eCPMV, is additionally recognized by TLR7. Secretion of type I interferons (IFNs), which requires the interaction between TLR7 and encapsulated single-stranded RNAs (ssRNAs), is critical to CPMV's better efficacy. The same recognition mechanisms are also functional in human peripheral blood mononuclear cells (PBMCs). Overall, these findings link CPMV immunotherapy efficacy with molecular recognition, provide rationale for how to develop more potent viral particles, accentuate the value of multi-TLR agonists as in situ cancer vaccines, and highlight the functional importance of type I IFNs for in situ vaccination.
Topics: Animals; Comovirus; HEK293 Cells; Humans; Leukocytes, Mononuclear; Mice; Myeloid Differentiation Factor 88; Toll-Like Receptors
PubMed: 34126409
DOI: 10.1016/j.biomaterials.2021.120914