50 research outputs found

    Mannosylated Cationic Copolymers for Gene Delivery to Macrophages

    Get PDF
    Macrophages are desirable targets for gene therapy of cancer and other diseases. Cationic diblock copolymers of polyethylene glycol (PEG) and poly-L-lysine (PLL) or poly{N-[N-(2-aminoethyl)-2-aminoethyl]aspartamide} (pAsp(DET)) are synthesized and used to form polyplexes with a plasmid DNA (pDNA) that are decorated with mannose moieties, serving as the targeting ligands for the C type lectin receptors displayed at the surface of macrophages. The PEG-b-PLL copolymers are known for its cytotoxicity, so PEG-b-PLL-based polyplexes are cross-linked using reducible reagent dithiobis(succinimidyl propionate) (DSP). The cross-linked polyplexes display low toxicity to both mouse embryonic fibroblasts NIH/3T3 cell line and mouse bone marrow-derived macrophages (BMMΦ). In macrophages mannose-decorated polyplexes demonstrate an ≈8 times higher transfection efficiency. The cross-linking of the polyplexes decrease the toxicity, but the transfection enhancement is moderate. The PEG-b-pAsp(DET) copolymers display low toxicity with respect to the IC-21 murine macrophage cell line and are used for the production of non-cross-linked pDNA-contained polyplexes. The obtained mannose modified polyplexes exhibit ca. 500-times greater transfection activity in IC-21 macrophages compared to the mannose-free polyplexes. This result greatly exceeds the targeting gene transfer effects previously described using mannose receptor targeted non-viral gene delivery systems. These results suggest that Man-PEG-b-pAsp(DET)/pDNA polyplex is a potential vector for immune cells-based gene therapy

    Pentagrams and paradoxes

    Full text link
    Klyachko and coworkers consider an orthogonality graph in the form of a pentagram, and in this way derive a Kochen-Specker inequality for spin 1 systems. In some low-dimensional situations Hilbert spaces are naturally organised, by a magical choice of basis, into SO(N) orbits. Combining these ideas some very elegant results emerge. We give a careful discussion of the pentagram operator, and then show how the pentagram underlies a number of other quantum "paradoxes", such as that of Hardy.Comment: 14 pages, 4 figure

    TPP1 Delivery to Lysosomes with Extracellular Vesicles and their Enhanced Brain Distribution in the Animal Model of Batten Disease

    Get PDF
    Extracellular vesicles (EVs) are promising natural nanocarriers for delivery of various types of therapeutics. Earlier engineered EV-based formulations for neurodegenerative diseases and cancer are reported. Herein, the use of macrophage-derived EVs for brain delivery of a soluble lysosomal enzyme tripeptidyl peptidase-1, TPP1, to treat a lysosomal storage disorder, Neuronal Ceroid Lipofuscinoses 2 (CLN2) or Batten disease, is investigated. TPP1 is loaded into EVs using two methods: i) transfection of parental EV-producing macrophages with TPP1-encoding plasmid DNA (pDNA) or ii) incorporation therapeutic protein TPP1 into naive empty EVs. For the former approach, EVs released by pretransfected macrophages contain the active enzyme and TPP1-encoding pDNA. To achieve high loading efficiency by the latter approach, sonication or permeabilization of EV membranes with saponin is utilized. Both methods provide proficient incorporation of functional TPP1 into EVs (EV-TPP1). EVs significantly increase stability of TPP1 against protease degradation and provide efficient TPP1 delivery to target cells in in vitro model of CLN2. The majority of EV-TPP1 (≈70%) is delivered to target organelles, lysosomes. Finally, a robust brain accumulation of EV carriers and increased lifespan is recorded in late-infantile neuronal ceroid lipofuscinosis (LINCL) mouse model following intraperitoneal administration of EV-TPP1

    Macrophage-Derived Extracellular Vesicles as Drug Delivery Systems for Triple Negative Breast Cancer (TNBC) Therapy

    Get PDF
    Efficient targeted delivery of anticancer agents to TNBC cells remains one of the greatest challenges to developing therapies. The lack of tumor-specific markers, aggressive nature of the tumor, and unique propensity to recur and metastasize make TNBC tumors more difficult to treat than other subtypes. We propose to exploit natural ability of macrophages to target cancer cells by means of extracellular vesicles (EVs) as drug delivery vehicles for chemotherapeutic agents, paclitaxel (PTX) and doxorubicin (Dox). We demonstrated earlier that macrophage-derived EVs loaded with PTX (EV-PTX) and Dox (EV-Dox) target cancer cells and exhibited high anticancer efficacy in a mouse model of pulmonary metastases. Herein, we report a manufacture and characterization of novel EV-based drug formulations using different loading procedures that were optimized by varying pH, temperature, and sonication conditions. Selected EV-based formulations showed a high drug loading, efficient accumulation in TNBC cells in vitro, and pronounced anti-proliferation effect. Drug-loaded EVs target TNBC in vivo, including the orthotopic mouse T11 tumors in immune competent BALB/C mice, and human MDA-MB-231 tumors in athymic nu/nu mice, and abolished tumor growth. Overall, EV-based formulations can provide a novel solution to a currently unmet clinical need and reduce the morbidity and mortality of TNBC patients

    Structural Changes and the Paradigm Transformation of the Government Policy on Lifelong Professional Education

    Full text link
    В настоящей концептуальной статье на основе анализа статистических данных об изменении средне-и долгосрочных потребностей и объемов подготовки кадров в различных подсистемах системы непрерывного профессионального образования рассматриваются гипотезы о вероятном развитии системы непрерывного профессионального образования России и концептуальные предложения по обусловленной этими изменениями приоритетов государственной политике в сфере непрерывного профессионального образования. Комплексный анализ тенденций структурных изменений системы непрерывного профессионального образования отечественными исследователями не проводился; данные зарубежной статистики [1] показывают, что аналогичные тенденции проявились в развитых странах раньше, чем в России. Причина написания статьи - привлечение внимания руководителей профессиональных образовательных организаций и органов управления профессиональным образованием к проблеме реструктуризации стратегических целей развития образования; идентификация проблемной области, актуальной для разработки стратегий развития вузов и сферы профессионального образования. Цели статьи достигаются с помощью анализа макроэкономических показателей потребностей в подготовке кадров по профессиональным образовательным программам разного уровня; сопоставления выявленных тенденций с аналогичными тенденциями за рубежом. Результаты проведенного исследования показали, что потребность в подготовке кадров в системе дополнительного профессионального образования значительно превышает потребности подготовки кадров по традиционным образовательным программам профессионального обучения, подготовки специалистов среднего звена и высшего образования. Причиной этого является ускорение технического и технологического прогресса и объективная неспособность традиционных образовательных программ обеспечить оперативное получение специалистами компетенций, соответствующих быстро возникающим потребностям. Следствием этого является необходимость пересмотра на уровне государства и работодателей приоритетов в развитии профессионального образования и механизмов его стимулирования. Ограничениями в этом может быть недостаточно институционализированная система взаимодействия органов управления образованием, работодателей и образовательных организаций.This conceptual article is based on the statistical data analysis of the changes in mid- and long-term needs and in the scope of personnel training within various systems of lifelong professional education. These data are used to hypothesize the potential direction of the development of this educational system in Russia and the conceptual priorities of the state policies in the area of professional education. The trends related to structural changes in lifelong professional education have never been systematically analyzed in Russia. Foreign statistics shows that such trends have first appeared in other developed countries. Therefore, the purpose of this article is to draw government officials’ and heads of professional educational institutions’ attention to the importance of restructuring the strategic goals of the educational system development, to identify the problem domain of working out the strategies for educational institutions and for the development of the professional education sphere. This purpose is achieved through the analysis of the macroeconomic parameters showing the need in personnel trained within professional educational programmes of various levels and through comparing the identified trends to those in other countries. The results show that the need for training personnel through the system of vocational professional education is much higher than that for training within traditional programmes of professional and higher education. The reason is the intensification of the technological progress and the objective incapability of the traditional educational programmes to provide specialists with competences required by the rapidly changing demands. As a result, the government and employers have to reconsider the priorities of professional education development and the ways to stimulate it. Still, there can be some limitations driven by weakly institutionalized system of interaction within the education management system, among employers and educational institutions

    Macrophage delivery of therapeutic nanozymes in a murine model of Parkinsons disease

    Get PDF
    Background: Parkinsons disease is a common progressive neurodegenerative disorder associated with profound nigrostriatal degeneration. Regrettably, no therapies are currently available that can attenuate disease progression. To this end, we developed a cell-based nanoformulation delivery system using the antioxidant enzyme catalase to attenuate neuroinflammatory processes linked to neuronal death. Methods: Nanoformulated catalase was obtained by coupling catalase to a synthetic polyelectrolyte of opposite charge, leading to the formation of a polyion complex micelle. The nanozyme was loaded into bone marrow macrophages and its transport to the substantia nigra pars compacta was evaluated in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-intoxicated mice. Results: Therapeutic efficacy of bone marrow macrophages loaded with nanozyme was confirmed by twofold reductions in microgliosis as measured by CD11b expression. A twofold increase in tyrosine hydroxylase-expressing dopaminergic neurons was detected in nanozyme-treated compared with untreated MPTP-intoxicated mice. Neuronal survival was confirmed by magnetic resonance spectroscopic imaging. Bone marrow macrophage-loaded catalase showed sustained release of the enzyme in plasma. Conclusion: These data support the importance of macrophage-based nanozyme carriage for Parkinsons disease therapies

    Cross-linked antioxidant nanozymes for improved delivery to CNS

    Get PDF
    Formulations of antioxidant enzymes, superoxide dismutase 1 (SOD1, also known as Cu/Zn SOD) and catalase were prepared by electrostatic coupling of enzymes with cationic block copolymers, polyethyleneimine-poly(ethylene glycol) or poly(L-lysine)-poly(ethylene glycol), followed by covalent cross-linking to stabilize nanoparticles (NPs). Different cross-linking strategies (using glutaraldehyde, bis-(sulfosuccinimidyl)suberate sodium salt or 1-Ethyl-3-[3-dimethylaminopropyl]carbodiimide hydrochloride with N-hydroxysulfosuccinimide) and reaction conditions (pH and polycation/protein charge ratio) were investigated that allowed immobilizing active enzymes in cross-linked NPs, termed "nanozymes." Bienzyme NPs, containing both SOD1 and catalase were also formulated. Formation of complexes was confirmed using denaturing gel electrophoresis and western blotting; physicochemical characterization was conducted using dynamic light scattering and atomic force microscopy. In vivo studies of 125I-labeled SOD1-containing nanozymes in mice demonstrated their increased stability in both blood and brain and increased accumulation in brain tissues, in comparison with non-cross-linked complexes and native SOD1. Future studies will evaluate the potential of these formulations for delivery of antioxidant enzymes to the central nervous system to attenuate oxidative stress associated with neurological diseases. From the Clinical Editor: Formulations of antioxidant enzyme complexes were demonstrated along with their increased stability in both blood and brain and increased accumulation in CNS tissue. Future studies will evaluate the potential of these formulations for antioxidant enzyme deliver to the CNS to attenuate oxidative stress in neurodegenerative diseases

    Macrophages with cellular backpacks for targeted drug delivery to the brain

    Get PDF
    Most potent therapeutics are unable to cross the blood-brain barrier following systemic administration, which necessitates the development of unconventional, clinically applicable drug delivery systems. With the given challenges, biologically active vehicles are crucial to accomplishing this task. We now report a new method for drug delivery that utilizes living cells as vehicles for drug carriage across the blood brain barrier. Cellular backpacks, 7–10 μm diameter polymer patches of a few hundred nanometers in thickness, are a potentially interesting approach, because they can act as drug depots that travel with the cell-carrier, without being phagocytized. Backpacks loaded with a potent antioxidant, catalase, were attached to autologous macrophages and systemically administered into mice with brain inflammation. Using inflammatory response cells enabled targeted drug transport to the inflamed brain. Furthermore, catalase-loaded backpacks demonstrated potent therapeutic effects deactivating free radicals released by activated microglia in vitro. This approach for drug carriage and release can accelerate the development of new drug formulations for all the neurodegenerative disorders

    Blood-borne macrophage-neural cell interactions hitchhike on endosome networks for cell-based nanozyme brain delivery

    Get PDF
    Background: Macrophage-carried nanoformulated catalase ('nanozyme) attenuates neuroinflammation and protects nigrostriatal neurons from 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine intoxication. This is facilitated by effective enzyme transfer from blood-borne macrophages to adjacent endothelial cells and neurons leading to the decomposition of reactive oxygen species. Materials & methods: We examined the intra- and inter-cellular trafficking mechanisms of nanozymes by confocal microscopy. Improved neuronal survival mediated by nanozyme-loaded macrophages was demonstrated by fluorescence-activated cell sorting. Results: In macrophages, nanozymes were internalized mainly by clathrin-mediated endocytosis then trafficked to recycling endosomes. The enzyme is subsequently released in exosomes facilitated by bridging conduits. Nanozyme transfer from macrophages to adjacent cells by endocytosis-independent mechanisms diffusing broadly throughout the recipient cells. In contrast, macrophage-free nanozymes were localized in lysosomes following endocytic entry. Conclusion: Facilitated transfer of nanozyme from cell to cell can improve neuroprotection against oxidative stress commonly seen during neurodegenerative disease processes

    Polyelectrolyte complex optimization for macrophage delivery of redox enzyme nanoparticles

    Get PDF
    Background: We posit that cell-mediated drug delivery can improve transport of therapeutic enzymes to the brain and decrease inflammation and neurodegeneration seen during Parkinsons disease. Our prior works demonstrated that macrophages loaded with nanoformulated catalase ('nanozyme) then parenterally injected protect the nigrostriatum in a murine model of Parkinsons disease. Packaging of catalase into block ionomer complex with a synthetic polyelectrolyte block copolymer precludes enzyme degradation in macrophages. Methods: We examined relationships between the composition and structure of block ionomer complexes with a range of block copolymers, their physicochemical characteristics, and loading, release and catalase enzymatic activity in bone marrow-derived macrophages. Results: Formation of block ionomer complexes resulted in improved aggregation stability. Block ionomer complexes with -polylysine and poly(L-glutamic acid)-poly(ethylene glycol) demonstrated the least cytotoxicity and high loading and release rates. However, these formulations did not efficiently protect catalase inside macrophages. Conclusion: Nanozymes with polyethyleneimine- and poly(L-lysine) 10-poly(ethylene glycol) provided the best protection of enzymatic activity for cell-mediated drug delivery
    corecore