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1.
Brief Bioinform ; 25(1)2023 11 22.
Article in English | MEDLINE | ID: mdl-38113077

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic has spurred a wide range of approaches to control and combat the disease. However, selecting an effective antiviral drug target remains a time-consuming challenge. Computational methods offer a promising solution by efficiently reducing the number of candidates. In this study, we propose a structure- and deep learning-based approach that identifies vulnerable regions in viral proteins corresponding to drug binding sites. Our approach takes into account the protein dynamics, accessibility and mutability of the binding site and the putative mechanism of action of the drug. We applied this technique to validate drug targeting toward severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike glycoprotein S. Our findings reveal a conformation- and oligomer-specific glycan-free binding site proximal to the receptor binding domain. This site comprises topologically important amino acid residues. Molecular dynamics simulations of Spike in complex with candidate drug molecules bound to the potential binding sites indicate an equilibrium shifted toward the inactive conformation compared with drug-free simulations. Small molecules targeting this binding site have the potential to prevent the closed-to-open conformational transition of Spike, thereby allosterically inhibiting its interaction with human angiotensin-converting enzyme 2 receptor. Using a pseudotyped virus-based assay with a SARS-CoV-2 neutralizing antibody, we identified a set of hit compounds that exhibited inhibition at micromolar concentrations.


Subject(s)
COVID-19 , Deep Learning , Humans , Protein Binding , Binding Sites , SARS-CoV-2/metabolism , Molecular Dynamics Simulation , Antibodies, Viral , Spike Glycoprotein, Coronavirus/metabolism
2.
Proc Natl Acad Sci U S A ; 119(46): e2210562119, 2022 Nov 16.
Article in English | MEDLINE | ID: mdl-36343224

ABSTRACT

The development of chimeric antigen receptor (CAR) T cell therapy has become a critical milestone in modern oncotherapy. Despite the remarkable in vitro effectiveness, the problem of safety and efficacy of CAR T cell therapy against solid tumors is challenged by the lack of tumor-specific antigens required to avoid on-target off-tumor effects. Spatially separating the cytotoxic function of CAR T cells from tumor antigen recognition provided by protein mediators allows for the precise control of CAR T cell cytotoxicity. Here, the high affinity and capability of the bacterial toxin-antitoxin barnase-barstar system were adopted to guide CAR T cells to solid tumors. The complementary modules based on (1) ankyrin repeat (DARPin)-barnase proteins and (2) barstar-based CAR (BsCAR) were designed to provide switchable targeting to tumor cells. The alteration of the DARPin-barnase switches enabled the targeting of different tumor antigens with a single BsCAR. A gradual increase in cytokine release and tunable BsCAR T cell cytotoxicity was achieved by varying DARPin-barnase loads. Switchable BsCAR T cell therapy was able to eradicate the HER2+ ductal carcinoma in vivo. Guiding BsCAR T cells by DARPin-barnase switches provides a universal approach for a controlled multitargeted adoptive immunotherapy.


Subject(s)
Neoplasms , T-Lymphocytes , Humans , Receptors, Antigen, T-Cell , Immunotherapy, Adoptive , Neoplasms/metabolism , Antigens, Neoplasm
3.
Histochem Cell Biol ; 161(6): 507-519, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38597938

ABSTRACT

The unique properties of superparamagnetic iron oxide nanoparticles (SPIONs) enable their use as magnetic biosensors, targeted drug delivery, magnetothermia, magnetic resonance imaging, etc. Today, SPIONs are the only type of metal oxide nanoparticles approved for biomedical application. In this work, we analyzed the cellular response to the previously reported luminescent silica coated SPIONs of the two cell types: M-HeLa cells and primary motor neuron culture. Both internalization pathways and intracellular fate of SPIONs have been compared for these cell lines using fluorescence and transmission electron microscopy. We also applied a pharmacological approach to analyze the endocytosis pathways of SPIONs into the investigated cell lines. The penetration of SPIONs into M-HeLa cells is already noticeable within 30 s of incubation through both caveolin-dependent endocytosis and micropinocytosis. However, incubation for a longer time (1 h at least) is required for the internalization of SPIONs into motor neuron culture cells provided by dynamin-dependent endocytosis and macropinocytosis. The intracellular colocalization assay reveals that the lysosomal internalization pathway of SPIONs is also dependent on the cell type. The lysosomal pathway is much more pronounced for M-HeLa cells compared with motor neurons. The emphasized differences in cellular responses of the two cell lines open up new opportunities in the application of SPIONs in the diagnostics and therapy of cancer cells.


Subject(s)
Endocytosis , Lysosomes , Motor Neurons , Silicon Dioxide , Silicon Dioxide/chemistry , Silicon Dioxide/metabolism , Lysosomes/metabolism , Humans , Motor Neurons/metabolism , Motor Neurons/cytology , HeLa Cells , Cells, Cultured , Magnetite Nanoparticles/chemistry , Animals , Magnetic Iron Oxide Nanoparticles/chemistry
4.
Mol Ther ; 30(12): 3658-3676, 2022 12 07.
Article in English | MEDLINE | ID: mdl-35715953

ABSTRACT

The full potential of tumor-infiltrating lymphocyte (TIL) therapy has been hampered by the inadequate activation and low persistence of TILs, as well as inefficient neoantigen presentation by tumors. We transformed tumor cells into artificial antigen-presenting cells (aAPCs) by infecting them with a herpes simplex virus 1 (HSV-1)-based oncolytic virus encoding OX40L and IL12 (OV-OX40L/IL12) to provide local signals for optimum T cell activation. The infected tumor cells displayed increased expression of antigen-presenting cell-related markers and induced enhanced T cell activation and killing in coculture with TILs. Combining OV-OX40L/IL12 and TIL therapy induced complete tumor regression in patient-derived xenograft and syngeneic mouse tumor models and elicited an antitumor immunological memory. In addition, the combination therapy produced aAPC properties in tumor cells, activated T cells, and reprogrammed macrophages to a more M1-like phenotype in the tumor microenvironment. This combination strategy unleashes the full potential of TIL therapy and warrants further evaluation in clinical studies.


Subject(s)
Oncolytic Viruses , Humans , Animals , Mice , Oncolytic Viruses/genetics , Lymphocytes, Tumor-Infiltrating , Antigen-Presenting Cells
5.
Blood Press ; 32(1): 2274595, 2023 12.
Article in English | MEDLINE | ID: mdl-37885101

ABSTRACT

OBJECTIVE: 24-hour ambulatory blood pressure monitoring (24ABPM) is state of the art in out-of-office blood pressure (BP) monitoring. Due to discomfort and technical limitations related to cuff-based 24ABPM devices, methods for non-invasive and continuous estimation of BP without the need for a cuff have gained interest. The main aims of the present study were to compare accuracy of a pulse arrival time (PAT) based BP-model and user acceptability of a prototype cuffless multi-sensor device (cuffless device), developed by Aidee Health AS, with a conventional cuff-based oscillometric device (ReferenceBP) during 24ABPM. METHODS: Ninety-five normotensive and hypertensive adults underwent simultaneous 24ABPM with the cuffless device on the chest and a conventional cuff-based oscillometric device on the non-dominant arm. PAT was calculated using the electrocardiogram (ECG) and photoplethysmography (PPG) sensors incorporated in the chest-worn device. The cuffless device recorded continuously, while ReferenceBP measurements were taken every 20 minutes during daytime and every 30 minutes during nighttime. Two-minute PAT-based BP predictions corresponding to the ReferenceBP measurements were compared with ReferenceBP measurements using paired t-tests, bias, and limits of agreement. RESULTS: Mean (SD) of ReferenceBP compared to PAT-based daytime and nighttime systolic BP (SBP) were 129.7 (13.8) mmHg versus 133.6 (20.9) mmHg and 113.1 (16.5) mmHg versus 131.9 (23.4) mmHg. Ninety-five % limits of agreements were [-26.7, 34.6 mmHg] and [-20.9, 58.4 mmHg] for daytime and nighttime SBP respectively. The cuffless device was reported to be significantly more comfortable and less disturbing than the ReferenceBP device during 24ABPM. CONCLUSIONS: In the present study, we demonstrated that a general PAT-based BP model had unsatisfactory agreement with ambulatory BP during 24ABPM, especially during nighttime. If sufficient accuracy can be achieved, cuffless BP devices have promising potential for clinical assessment of BP due to the opportunities provided by continuous BP measurements during real-life conditions and high user acceptability.


What is the context?Hypertension is a major risk factor for cardiovascular and cerebrovascular end-organ damage, morbidity, and mortality world-wide.Accurate measurement of blood pressure is essential for the diagnosis and management of hypertension.What is new?Cuffless blood pressure devices that allow measurement of blood pressure without a pressure cuff is a promising and novel method of blood pressure estimation.The objective of this study is to assess whether pulse arrival time alone can be used to estimate blood pressure accurately during 24-hour ambulatory blood pressure monitoring, using a prototype cuffless device placed on the chest.Our analysis shows that a general model based on pulse arrival time overestimated ambulatory blood pressure, especially during nighttime.User acceptability was higher with the cuffless device compared to a conventional cuff-based oscillometric device during 24-hour ambulatory blood pressure monitoring.What is the impact?This study provides further evidence that accurate blood pressure estimations cannot be achieved by using pulse arrival time alone as a surrogate for blood pressure measurements.


Subject(s)
Blood Pressure Monitoring, Ambulatory , Hypertension , Adult , Humans , Blood Pressure/physiology , Blood Pressure Determination/methods , Hypertension/diagnosis , Heart Rate , Pulse Wave Analysis/methods
6.
Nanomedicine ; 49: 102665, 2023 04.
Article in English | MEDLINE | ID: mdl-36822334

ABSTRACT

The silica nanoparticles (SNs) co-doped with paramagnetic ([Mn(HL)]n-,) and luminescent ([Ru(dipy)3]2+) complexes are represented. The specific distribution of [Mn(HL)]n- within the SNs allows to achieve about ten-fold enhancing in magnetic relaxivities in comparison with those of [Mn(HL)]n- in solutions. The leaching of [Mn(HL)]n- from the shell can be minimized through the co-doping of [Ru(dipy)3]2+ into the core of the SNs. The co-doped SNs exhibit colloid stability in aqueous solutions, including those modeling a blood serum. The surface of the co-doped SNs was also decorated by amino- and carboxy-groups. The cytotoxicity, hemoagglutination and hemolytic activities of the co-doped SNs are on the levels convenient for "in vivo" studies, although the amino-decorated SNs cause more noticeable agglutination and suppression of cell viability. The co-doped SNs being intravenously injected into mice allows to reveal their biodistribution in both ex vivo and in vivo conditions through confocal microscopy and magnetic resonance imaging correspondingly.


Subject(s)
Nanoparticles , Silicon Dioxide , Animals , Mice , Tissue Distribution , Contrast Media , Magnetic Resonance Imaging/methods
7.
Proc Natl Acad Sci U S A ; 117(37): 22841-22848, 2020 09 15.
Article in English | MEDLINE | ID: mdl-32859757

ABSTRACT

Quantum mechanics/molecular mechanics (QM/MM) maturation of an immunoglobulin (Ig) powered by supercomputation delivers novel functionality to this catalytic template and facilitates artificial evolution of biocatalysts. We here employ density functional theory-based (DFT-b) tight binding and funnel metadynamics to advance our earlier QM/MM maturation of A17 Ig-paraoxonase (WTIgP) as a reactibody for organophosphorus toxins. It enables regulation of biocatalytic activity for tyrosine nucleophilic attack on phosphorus. The single amino acid substitution l-Leu47Lys results in 340-fold enhanced reactivity for paraoxon. The computed ground-state complex shows substrate-induced ionization of the nucleophilic l-Tyr37, now H-bonded to l-Lys47, resulting from repositioning of l-Lys47. Multiple antibody structural homologs, selected by phenylphosphonate covalent capture, show contrasting enantioselectivities for a P-chiral phenylphosphonate toxin. That is defined by crystallographic analysis of phenylphosphonylated reaction products for antibodies A5 and WTIgP. DFT-b analysis using QM regions based on these structures identifies transition states for the favored and disfavored reactions with surprising results. This stereoselection analysis is extended by funnel metadynamics to a range of WTIgP variants whose predicted stereoselectivity is endorsed by experimental analysis. The algorithms used here offer prospects for tailored design of highly evolved, genetically encoded organophosphorus scavengers and for broader functionalities of members of the Ig superfamily, including cell surface-exposed receptors.

8.
Sensors (Basel) ; 23(18)2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37765958

ABSTRACT

Crop identification is one of the most important tasks in digital farming. The use of remote sensing data makes it possible to clarify the boundaries of fields and identify fallow land. This study considered the possibility of using the seasonal variation in the Dual-polarization Radar Vegetation Index (DpRVI), which was calculated based on data acquired by the Sentinel-1B satellite between May and October 2021, as the main characteristic. Radar images of the Khabarovskiy District of the Khabarovsk Territory, as well as those of the Arkharinskiy, Ivanovskiy, and Oktyabrskiy districts in the Amur Region (Russian Far East), were obtained and processed. The identifiable classes were soybean and oat crops, as well as fallow land. Classification was carried out using the Support Vector Machines, Quadratic Discriminant Analysis (QDA), and Random Forest (RF) algorithms. The training (848 ha) and test (364 ha) samples were located in Khabarovskiy District. The best overall accuracy on the test set (82.0%) was achieved using RF. Classification accuracy at the field level was 79%. When using the QDA classifier on cropland in the Amur Region (2324 ha), the overall classification accuracy was 83.1% (F1 was 0.86 for soybean, 0.84 for fallow, and 0.79 for oat). Application of the Radar Vegetation Index (RVI) and VV/VH ratio enabled an overall classification accuracy in the Amur region of 74.9% and 74.6%, respectively. Thus, using DpRVI allowed us to achieve greater performance compared to other SAR data, and it can be used to identify crops in the south of the Far East and serve as the basis for the automatic classification of cropland.

9.
Small ; 17(45): e2102643, 2021 11.
Article in English | MEDLINE | ID: mdl-34605165

ABSTRACT

Development of CAR-T therapy led to immediate success in the treatment of B cell leukemia. Manufacturing of therapy-competent functional CAR-T cells needs robust protocols for ex vivo/in vitro expansion of modified T-cells. This step is challenging, especially if non-viral low-efficiency delivery protocols are used to generate CAR-T cells. Modern protocols for CAR-T cell expansion are imperfect since non-specific stimulation results in rapid outgrowth of CAR-negative T cells, and removal of feeder cells from mixed cultures necessitates additional purification steps. To develop a specific and improved protocol for CAR-T cell expansion, cell-derived membrane vesicles are taken advantage of, and the simple structural demands of the CAR-antigen interaction. This novel approach is to make antigenic microcytospheres from common cell lines stably expressing surface-bound CAR antigens, and then use them for stimulation and expansion of CAR-T cells. The data presented in this article clearly demonstrate that this protocol produced antigen-specific vesicles with the capacity to induce stronger stimulation, proliferation, and functional activity of CAR-T cells than is possible with existing protocols. It is predicted that this new methodology will significantly advance the ability to obtain improved populations of functional CAR-T cells for therapy.


Subject(s)
Immunotherapy, Adoptive , T-Lymphocytes , Cell Line, Tumor
10.
Proc Natl Acad Sci U S A ; 115(30): E7023-E7032, 2018 07 24.
Article in English | MEDLINE | ID: mdl-29987039

ABSTRACT

The diverse physiological roles of the neurotrophin family have long prompted exploration of their potential as therapeutic agents for nerve injury and neurodegenerative diseases. To date, clinical trials of one family member, brain-derived neurotrophic factor (BDNF), have disappointingly failed to meet desired endpoints. Contributing to these failures is the fact that BDNF is pharmaceutically a nonideal biologic drug candidate. It is a highly charged, yet is a net hydrophobic molecule with a low molecular weight that confers a short t1/2 in man. To circumvent these shortcomings of BDNF as a drug candidate, we have employed a function-based cellular screening assay to select activating antibodies of the BDNF receptor TrkB from a combinatorial human short-chain variable fragment antibody library. We report here the successful selection of several potent TrkB agonist antibodies and detailed biochemical and physiological characterization of one such antibody, ZEB85. By using a human TrkB reporter cell line and BDNF-responsive GABAergic neurons derived from human ES cells, we demonstrate that ZEB85 is a full agonist of TrkB, comparable in potency to BDNF toward human neurons in activation of TrkB phosphorylation, canonical signal transduction, and mRNA transcriptional regulation.


Subject(s)
Autocrine Communication , GABAergic Neurons/metabolism , Gene Library , Membrane Glycoproteins/agonists , Receptor, trkB/agonists , Signal Transduction/drug effects , Single-Chain Antibodies , Transcription, Genetic/drug effects , Cell Line , Humans , Membrane Glycoproteins/genetics , Membrane Glycoproteins/metabolism , Phosphorylation/drug effects , Receptor, trkB/genetics , Receptor, trkB/metabolism , Single-Chain Antibodies/genetics , Single-Chain Antibodies/pharmacology
11.
Bioconjug Chem ; 30(5): 1500-1506, 2019 05 15.
Article in English | MEDLINE | ID: mdl-31021608

ABSTRACT

Specific recognition of ligands by surface receptors of eukaryotic cells is a fundamental process in sensing of the exogenous environment, including cell-to-cell communication. These interactions are therefore widely probed in both basic studies and drug development to enhance or interrupt them. Here, we designed a high-throughput publicly available platform for visualization and selection of eukaryotic cells according to the specificity of surface-exposed receptors by consolidation of phage display and flow cytometry techniques. Polypeptide ligands for membrane receptors are incorporated into every copy of p3 protein of M13K07 bacteriophage, which is intracellularly biotinylated to further accept PE-Cy7-labled streptavidin. Transgenic antigen-specific B-cells expressing membrane-tethered lymphoid B-cell receptor in a single-chain format interacted with engineered bacteriophages exposing the polypeptide ligand with an unprecedented selectivity of 97% and a false-positive detection value of 2.0%. Multivalent binding of the phage bioconjugates with the receptor provided significantly better specificity and sensitivity allowing application of engineered bacteriophage bioconjugates at a concentration 3 orders of magnitude lower in comparison with synthetic biotinylated peptide. We suggest that the platform described in this work may be applied either for routine staining or characterization of orphan membrane receptors exposed on the surface of living mammalian cells in their native environment.


Subject(s)
Bacteriophages/chemistry , Receptors, Cell Surface/chemistry , Biotin/chemistry , Cell Surface Display Techniques , Molecular Probes
12.
Phys Chem Chem Phys ; 21(46): 25707-25719, 2019 Nov 27.
Article in English | MEDLINE | ID: mdl-31720635

ABSTRACT

To prevent irreversible damage caused by an excess of incident light, the photosynthetic machinery of many cyanobacteria uniquely utilizes the water-soluble orange carotenoid protein (OCP) containing a single keto-carotenoid molecule. This molecule is non-covalently embedded into the two OCP domains which are interconnected by a flexible linker. The phenomenon of OCP photoactivation, causing significant changes in carotenoid absorption in the orange and red form of OCP, is currently being thoroughly studied. Numerous additional spectral forms of natural and synthetic OCP-like proteins have been unearthed. The optical properties of carotenoids are strongly determined by the interaction of their electronic states with vibrational modes, the surrounding protein matrix, and the solvent. In this work, the effects of the pigment-protein interaction and vibrational relaxation in OCP were studied by computational simulation of linear absorption. Taking into account Raman spectroscopy data and applying the multimode Brownian oscillator model as well as the cumulant expansion technique, we have calculated a set of characteristic microparameters sufficient to demarcate different carotenoid states in OCP forms, using the model carotenoids spheroidene and spheroidenone in methanol/acetone solution as benchmarks. The most crucial microparameters, which determine the effect of solvent and protein environment, are the Huang-Rhys factors and the frequencies of C[double bond, length as m-dash]C and C-C stretching modes, the low-frequency mode and the FWHM due to inhomogeneous line broadening. Considering the difference of linear absorption between spheroidene and spheroidenone, which remarkably resembles the photoinduced changes of OCP absorption, and applying quantum chemical calculations, we discuss structural and functional determinants of carotenoid binding proteins.


Subject(s)
Bacterial Proteins/chemistry , Carotenoids/chemistry , Molecular Dynamics Simulation , Quantum Theory , Water/chemistry , Molecular Structure , Solubility
13.
FASEB J ; 29(5): 1901-13, 2015 May.
Article in English | MEDLINE | ID: mdl-25634956

ABSTRACT

Recent findings indicate that the ubiquitin-proteasome system is involved in the pathogenesis of cancer as well as autoimmune and several neurodegenerative diseases, and is thus a target for novel therapeutics. One disease that is related to aberrant protein degradation is multiple sclerosis, an autoimmune disorder involving the processing and presentation of myelin autoantigens that leads to the destruction of axons. Here, we show that brain-derived proteasomes from SJL mice with experimental autoimmune encephalomyelitis (EAE) in an ubiquitin-independent manner generate significantly increased amounts of myelin basic protein peptides that induces cytotoxic lymphocytes to target mature oligodendrocytes ex vivo. Ten times enhanced release of immunogenic peptides by cerebral proteasomes from EAE-SJL mice is caused by a dramatic shift in the balance between constitutive and ß1i(high) immunoproteasomes in the CNS of SJL mice with EAE. We found that during EAE, ß1i is increased in resident CNS cells, whereas ß5i is imported by infiltrating lymphocytes through the blood-brain barrier. Peptidyl epoxyketone specifically inhibits brain-derived ß1i(high) immunoproteasomes in vitro (kobs/[I] = 240 M(-1)s(-1)), and at a dose of 0.5 mg/kg, it ameliorates ongoing EAE in vivo. Therefore, our findings provide novel insights into myelin metabolism in pathophysiologic conditions and reveal that the ß1i subunit of the immunoproteasome is a potential target to treat autoimmune neurologic diseases.


Subject(s)
Autoimmunity/immunology , Blood-Brain Barrier/metabolism , Brain/immunology , Encephalomyelitis, Autoimmune, Experimental/immunology , Lymphocyte Activation/immunology , Myelin Basic Protein/metabolism , Proteasome Endopeptidase Complex/immunology , Animals , Blotting, Western , Brain/metabolism , Brain/pathology , Cells, Cultured , Chromatography, Liquid , Encephalomyelitis, Autoimmune, Experimental/metabolism , Encephalomyelitis, Autoimmune, Experimental/pathology , Female , Immunoenzyme Techniques , Mice , Mice, Inbred BALB C , Myelin Basic Protein/immunology , Myelin Sheath/metabolism , Protein Subunits , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Tandem Mass Spectrometry , Ubiquitin/metabolism
14.
Mediators Inflamm ; 2016: 2847232, 2016.
Article in English | MEDLINE | ID: mdl-27239100

ABSTRACT

We have previously shown that immunodominant MBP peptides encapsulated in mannosylated liposomes (Xemys) effectively suppressed experimental allergic encephalomyelitis (EAE). Within the frames of the successfully completed phase I clinical trial, we investigated changes in the serum cytokine profile after Xemys administration in MS patients. We observed a statistically significant decrease of MCP-1/CCL2, MIP-1ß/CCL4, IL-7, and IL-2 at the time of study completion. In contrast, the serum levels of TNF-α were remarkably elevated. Our data suggest that the administration of Xemys leads to a normalization of cytokine status in MS patients to values commonly reported for healthy subjects. These data are an important contribution for the upcoming Xemys clinical trials.


Subject(s)
Chemokine CCL2/blood , Chemokine CCL4/blood , Interleukin-2/blood , Liposomes/chemistry , Multiple Sclerosis/blood , Multiple Sclerosis/drug therapy , Myelin Basic Protein/therapeutic use , Tumor Necrosis Factor-alpha/blood , Adult , Animals , Female , Humans , Interleukin-7/metabolism , Male , Mice , Middle Aged , Multiple Sclerosis/metabolism , Young Adult
15.
Biotechnol Lett ; 38(7): 1173-80, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27099070

ABSTRACT

OBJECTIVE: Myelin oligodendrocyte glycoprotein (MOG) is one of the major autoantigens in multiple sclerosis (MS), therefore selective depletion of autoreactive lymphocytes exposing MOG-specific B cell receptors (BCRs) would be beneficial in terms of MS treatment. RESULTS: Using E. coli we generated an efficient protocol for the purification of the recombinant immunotoxin DT-MOG composed of the extracellular Ig-like domain of MOG fused in frame with the catalytic and translocation subunits of diphtheria toxin (DT, Corynebacterium diphtheriae) under native conditions with a final yield of 1.5 mg per liter of culture medium. Recombinant DT-MOG was recognized in vitro by MOG-reactive antibodies and has catalytic activity comparable with wild-type DT. CONCLUSION: Enhanced pharmacokinetics (mean residence time in the bloodstream of 61 min) and minimized diminished nonspecific toxicity (LD50 = 1.76 mg/kg) of the DT-MOG makes it a potential candidate for the immunotherapy of MS.


Subject(s)
Diphtheria Toxin/metabolism , Immunotherapy/methods , Immunotoxins/metabolism , Myelin-Oligodendrocyte Glycoprotein/immunology , Receptors, Antigen, B-Cell/metabolism , Diphtheria Toxin/genetics , Diphtheria Toxin/immunology , Escherichia coli/genetics , Escherichia coli/metabolism , Immunotoxins/genetics , Immunotoxins/immunology , Receptors, Antigen, B-Cell/genetics , Receptors, Antigen, B-Cell/immunology
16.
FASEB J ; 27(1): 222-31, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23047895

ABSTRACT

Multiple sclerosis (MS) is a severe inflammatory and neurodegenerative disease with an autoimmune background. Despite the variety of therapeutics available against MS, the development of novel approaches to its treatment is of high importance in modern pharmaceutics. In this study, experimental autoimmune encephalomyelitis (EAE) in Dark Agouti rats has been treated with immunodominant peptides of the myelin basic protein (MBP) encapsulated in mannosylated small unilamellar vesicles. The results show that liposome-encapsulated MBP(46-62) is the most effective in reducing maximal disease score during the first attack, while MBP(124-139) and MBP(147-170) can completely prevent the development of the exacerbation stage. Both mannosylation of liposomes and encapsulation of peptides are critical for the therapeutic effect, since neither naked peptides nor nonmannosylated liposomes, loaded or empty, have proved effective. The liposome-mediated synergistic effect of the mixture of 3 MBP peptides significantly suppresses the progression of protracted EAE, with the median cumulative disease score being reduced from 22 to 14 points, compared to the placebo group; prevents the production of circulating autoantibodies; down-regulates the synthesis of Th1 cytokines; and induces the production of brain-derived neurotrophic factor in the central nervous system. Thus, the proposed formulation ameliorates EAE, providing for a less severe first attack and rapid recovery from exacerbation, and offers a promising therapeutic modality in MS treatment.


Subject(s)
Encephalitis/prevention & control , Hypersensitivity/prevention & control , Liposomes , Peptides/therapeutic use , Animals , Blotting, Western , Encephalitis/etiology , Enzyme-Linked Immunosorbent Assay , Female , Humans , Hypersensitivity/complications , Mice , Rats , Surface Plasmon Resonance
17.
Front Med (Lausanne) ; 10: 1154041, 2023.
Article in English | MEDLINE | ID: mdl-37138759

ABSTRACT

Objective: Continuous non-invasive cuffless blood pressure (BP) monitoring may reduce adverse outcomes in hospitalized patients if accuracy is approved. We aimed to investigate accuracy of two different BP prediction models in critically ill intensive care unit (ICU) patients, using a prototype cuffless BP device based on electrocardiogram and photoplethysmography signals. We compared a pulse arrival time (PAT)-based BP model (generalized PAT-based model) derived from a general population cohort to more complex and individualized models (complex individualized models) utilizing other features of the BP sensor signals. Methods: Patients admitted to an ICU with indication of invasive BP monitoring were included. The first half of each patient's data was used to train a subject-specific machine learning model (complex individualized models). The second half was used to estimate BP and test accuracy of both the generalized PAT-based model and the complex individualized models. A total of 7,327 measurements of 15 s epochs were included in pairwise comparisons across 25 patients. Results: The generalized PAT-based model achieved a mean absolute error (SD of errors) of 7.6 (7.2) mmHg, 3.3 (3.1) mmHg and 4.6 (4.4) mmHg for systolic BP, diastolic BP and mean arterial pressure (MAP) respectively. Corresponding results for the complex individualized model were 6.5 (6.7) mmHg, 3.1 (3.0) mmHg and 4.0 (4.0) mmHg. Percentage of absolute errors within 10 mmHg for the generalized model were 77.6, 96.2, and 89.6% for systolic BP, diastolic BP and MAP, respectively. Corresponding results for the individualized model were 83.8, 96.2, and 94.2%. Accuracy was significantly improved when comparing the complex individualized models to the generalized PAT-based model in systolic BP and MAP, but not diastolic BP. Conclusion: A generalized PAT-based model, developed from a different population was not able to accurately track BP changes in critically ill ICU patients. Individually fitted models utilizing other cuffless BP sensor signals significantly improved accuracy, indicating that cuffless BP can be measured non-invasively, but the challenge toward generalizable models remains for future research to resolve.

18.
Nanomaterials (Basel) ; 13(8)2023 Apr 12.
Article in English | MEDLINE | ID: mdl-37110936

ABSTRACT

In this study, Nickel oxide-based catalysts (NixOx) were synthesized and used for the in-situ upgrading process of heavy crude oil (viscosity 2157 mPa·s, and API gravity of 14.1° at 25 °C) in aquathermolysis conditions for viscosity reduction and heavy oil recovery. All characterizations of the obtained nanoparticles catalysts (NixOx) were performed through Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Atomic Force Microscopy (AFM), X-Ray and Diffraction (XRD), and ASAP 2400 analyzer from Micromeritics (USA), methods. Experiments of catalytic and non-catalytic upgrading processes were carried out in a discontinuous reactor at a temperature of 300 °C and 72 bars for 24 h and 2% of catalyst ratio to the total weight of heavy crude oil. XRD analysis revealed that the use of nanoparticles of NiO significantly participated in the upgrading processes (by desulfurization) where different activated form catalysts were observed, such as α-NiS, ß-NiS, Ni3S4, Ni9S8, and NiO. The results of viscosity analysis, elemental analysis, and 13C NMR analysis revealed that the viscosity of heavy crude oil decreased from 2157 to 800 mPa·s, heteroatoms removal from heavy oil ranged from S-4.28% to 3.32% and N-0.40% to 0.37%, and total content of fractions (ΣC8-C25) increased from 59.56% to a maximum of 72.21%, with catalyst-3 thank to isomerization of normal and cyclo-alkanes and dealkylation of lateral chains of aromatics structures, respectively. Moreover, the obtained nanoparticles showed good selectivity, promoting in-situ hydrogenation-dehydrogenation reactions, and hydrogen redistribution over carbons (H/C) is improved, ranging from 1.48 to a maximum of 1.77 in sample catalyst-3. On the other hand, the use of nanoparticle catalysts have also impacted the hydrogen production, where the H2/CO provided from the water gas shift reaction has increased. Nickel oxide catalysts have the potential for in-situ hydrothermal upgrading of heavy crude oil because of their great potential to catalyze the aquathermolysis reactions in the presence of steam.

19.
Front Endocrinol (Lausanne) ; 14: 1127173, 2023.
Article in English | MEDLINE | ID: mdl-37152923

ABSTRACT

Background: Insulinomas are very rare in childhood with sparse knowledge on the clinical aspects and the presence of Multiple Endocrine Neoplasia type 1 (MEN1). Methods: We conducted a retrospective review of patients diagnosed with insulinoma between 1995 and 2021, presenting to one referral centre in Russia. Clinical, biochemical, genetic, imaging and histological data were collected. In addition, follow-up and family data were obtained. Results: A total of twenty-two children aged 5 to 16 years were identified. The median (range) gap between the first hypoglycaemia symptoms and diagnosis was 10 (1-46) months. Twelve children (55%) were misdiagnosed to have epilepsy and were treated with anticonvulsants before hypoglycemia was revealed. Contrast enhanced MRI and/or CT were accurate to localize the lesion in 82% (n=18). Five patients (23%) had multiple pancreatic lesions. All children underwent surgical treatment. The median (range) diameter of removed tumors was 1.5 (0.3-6) cm. Histopathological studies confirmed the presence of insulinoma in all cases. Immunohistochemical studies revealed G2 differentiation grade in 10 out of 17 cases. Two patients were diagnosed with metastatic insulinoma. One of them had metastases at the time of insulinoma diagnosis, while the other was diagnosed with liver metastases eight years after the surgery. Eight children (36%) were found to carry MEN1 mutations, inherited n=5, de novo n=1, no data, n=2. Children with MEN1 had significantly higher number of pancreatic tumors compared to sporadic cases. All of them developed additional MEN1 symptoms during the following 2-13 years. In the five patients with inherited MEN1, seven family members had hitherto undiscovered MEN1 manifestations. Conclusions: In this large cohort of children with rare pediatric insulinomas, MEN1 syndrome and G2 tumors were frequent, as well as hitherto undiscovered MEN1 manifestations in family members. Our data emphasize the need of genetic testing in all children with insulinoma and their relatives, even in the absence of any other features, as well as the importance of a prolonged follow-up observation.


Subject(s)
Hypoglycemia , Insulinoma , Multiple Endocrine Neoplasia Type 1 , Pancreatic Neoplasms , Humans , Child , Insulinoma/diagnosis , Insulinoma/genetics , Insulinoma/pathology , Retrospective Studies , Multiple Endocrine Neoplasia Type 1/genetics , Pancreatic Neoplasms/diagnosis , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , Referral and Consultation
20.
Nat Biomed Eng ; 2023 Oct 05.
Article in English | MEDLINE | ID: mdl-37798444

ABSTRACT

On-target off-tumour toxicity limits the anticancer applicability of chimaeric antigen receptor (CAR) T cells. Here we show that the tumour-targeting specificity and activity of T cells with a CAR consisting of an antibody with a lysine residue that catalytically forms a reversible covalent bond with a 1,3-diketone hapten can be regulated by the concentration of a small-molecule adapter. This adapter selectively binds to the hapten and to a chosen tumour antigen via a small-molecule binder identified via a DNA-encoded library. The adapter therefore controls the formation of a covalent bond between the catalytic antibody and the hapten, as well as the tethering of the CAR T cells to the tumour cells, and hence the cytotoxicity and specificity of the cytotoxic T cells, as we show in vitro and in mice with prostate cancer xenografts. Such small-molecule switches of T-cell cytotoxicity and specificity via an antigen-independent 'universal' CAR may enhance the control and safety profile of CAR-based cellular immunotherapies.

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