Publications

This study investigates the synthesis and optimization of nanobots (NBs) loaded with pDNA using the layer-by-layer (LBL) method and explores the impact of their collective motion on the transfection efficiency. NBs consist of biocompatible and biodegradable poly(lactic-co-glycolic acid) (PLGA) nanoparticles and are powered by the urease enzyme, enabling autonomous movement and collective swarming behavior. In vitro experiments were conducted to validate the delivery efficiency of fluorescently labeled NBs, using two-dimensional (2D) and three-dimensional (3D) cell models: murine urothelial carcinoma cell line (MB49) and spheroids from human urothelial bladder cancer cells (RT4). Swarms of pDNA-loaded NBs showed enhancements of 2.2- to 2.6-fold in delivery efficiency and 6.8- to 8.1-fold in material delivered compared to inhibited particles (inhibited enzyme) and the absence of fuel in a 2D cell culture. Additionally, efficient intracellular delivery of pDNA was demonstrated in both cell models by quantifying and visualizing the expression of eGFP. Swarms of NBs exhibited a >5-fold enhancement in transfection efficiency compared to the absence of fuel in a 2D culture, even surpassing the Lipofectamine 3000 commercial transfection agent (cationic lipid-mediated transfection). Swarms also demonstrated up to a 3.2-fold enhancement in the amount of material delivered in 3D spheroids compared to the absence of fuel. The successful transfection of 2D and 3D cell cultures using swarms of LBL PLGA NBs holds great potential for nucleic acid delivery in the context of bladder treatments.

JTD Keywords: Animals, Barrier, Cell line, tumor, Dna, Drug delivery, Drug-delivery, Enzyme catalysis, Gene delivery, Gene transfer techniques, Humans, Lactic acid, Mice, Nanobots, Nanoparticles, Pdna, Plasmids, Polyglycolic acid, Polylactic acid-polyglycolic acid copolymer, Swarming, Transfectio, Transfection, Urease, Urinary bladder neoplasms

Over the past decades, the development of nanoparticles (NPs) to increase the efficiency of clinical treatments has been subject of intense research. Yet, most NPs have been reported to possess low efficacy as their actuation is hindered by biological barriers. For instance, synovial fluid (SF) present in the joints is mainly composed of hyaluronic acid (HA). These viscous media pose a challenge for many applications in nanomedicine, as passive NPs tend to become trapped in complex networks, which reduces their ability to reach the target location. This problem can be addressed by using active NPs (nanomotors, NMs) that are self-propelled by enzymatic reactions, although the development of enzyme-powered NMs, capable of navigating these viscous environments, remains a considerable challenge. Here, the synergistic effects of two NMs troops, namely hyaluronidase NMs (HyaNMs, Troop 1) and urease NMs (UrNMs, Troop 2) are demonstrated. Troop 1 interacts with the SF by reducing its viscosity, thus allowing Troop 2 to swim more easily through the SF. Through their collective motion, Troop 2 increases the diffusion of macromolecules. These results pave the way for more widespread use of enzyme-powered NMs, e.g., for treating joint injuries and improving therapeutic effectiveness compared with traditional methods. The conceptual idea of the novel approach using hyaluronidase NMs (HyaNMs) to interact with and reduce the viscosity of the synovial fluid (SF) and urease NMs (UrNMs) for a more efficient transport of therapeutic agents in joints.image

JTD Keywords: Biological barrier, Clinical research, Clinical treatments, Collective motion, Collective motion,nanomotors,nanorobots,swarming,viscous medi, Collective motions, Complex networks, Enzymatic reaction, Enzymes, Hyaluronic acid, Hyaluronic-acid,ph,viscoelasticity,adsorption,barriers,behavior,ureas, Macromolecules, Medical nanotechnology, Nano robots, Nanomotors, Nanorobots, Swarming, Synovial fluid, Target location, Viscous media, Viscous medium

Human mesenchymal stromal cells (hMSCs) seeded on calcium phosphate (CaP) bioceramics are extensively explored in bone tissue engineering and have recently shown effective clinical outcomes. In previous pre-clinical studies, hMSCs-CaP-mediated bone formation was preceded by osteoclastogenesis at the implantation site. The current study evaluates to what extent phase composition of CaPs affects the osteoclast response and ultimately influence bone formation. To this end, four different CaP bioceramics were used, hydroxyapatite (HA), beta-tricalcium phosphate (beta-TCP) and two biphasic composites of HA/beta- TCP ratios of 60/40 and 20/80 respectively, for in vitro osteoclast differentiation and correlation with in vivo osteoclastogenesis and bone formation. All ceramics allowed osteoclast formation in vitro from mouse and human precursors, except for pure HA, which significantly impaired their maturation. Ectopic implantation alongside hMSCs in subcutis sites of nude mice revealed new bone formation at 8 weeks in all conditions with relative amounts for beta-TCP > biphasic CaPs > HA. Surprisingly, while hMSCs were essential for osteoinduction, their survival did not correlate with bone formation. By contrast, the degree of early osteoclastogenesis (2 weeks) seemed to define the extent of subsequent bone formation. Together, our findings suggest that the osteoclastic response could be used as a predictive marker in hMSC-CaPbased bone regeneration and strengthens the need to understand the underlying mechanisms for future biomaterial development. Statement of significance The combination of mesenchymal stromal cells (MSCs) and calcium phosphate (CaP) materials has demonstrated its safety and efficacy for bone regeneration in clinical trials, despite our insufficient understanding of the underlying biological mechanisms. Osteoclasts were previously suggested as key mediators between the early inflammatory phase following biomaterial implantation and the subsequent bone formation. Here we compared the affinity of osteoclasts for various CaP materials with different ratios of hydroxyapatite to beta-tricalcium phosphate. We found that osteoclast formation, both in vitro and at early stages in vivo, correlates with bone formation when the materials were implanted alongside MSCs in mice. Surprisingly, MSC survival did not correlate with bone formation, suggesting that the number or phenotype of osteoclasts formed was more important. (c) 2024 The Author(s). Published by Elsevier Ltd on behalf of Acta Materialia Inc. This is an open access article under the CC BY license ( http://creativecommons.org/licenses/by/4.0/ )

JTD Keywords: Acid phosphatase tartrate resistant isoenzyme, Animal, Animal cell, Animal experiment, Animal tissue, Animals, Article, Beta-tricalcium phosphate, Bioceramics, Biocompatible materials, Biomaterial, Bone, Bone development, Bone formation, Bone regeneration, Calcium phosphate, Calcium phosphate materials, Calcium phosphates, Cd14 antigen, Cell differentiation, Cell engineering, Cell maturation, Cell survival, Ceramics, Chemical composition, Controlled study, Correlation analysis, Correlation coefficient, Data correlation, Durapatite, Engraftment, Flowcharting, Human, Human cell, Human mesenchymal stromal cell, Human mesenchymal stromal cells, Humans, Hydroxyapatite, Hydroxyapatites, In vitro study, In vivo study, In-vitro, In-vivo, Mammals, Marrow stromal cells, Material composition, Material compositions, Mesenchymal stroma cell, Mesenchymal stromal cells, Mice, Mice, nude, Monocyte, Mouse, Nonhuman, Nude mouse, Ossification, Osteoclast, Osteoclastogenesis, Osteoclasts, Osteogenesis, Osteoinduction, Phase composition, Regeneration strategies, Resorption, Scaffolds, Stem-cells, Subcutaneous tissue, Tissue engineering, Transmission control protocol, Tri-calcium phosphates, Vimentin

Factor XII (FXII) is a zymogen present in blood that tends to adsorb onto the surfaces of blood-contacting medical devices. Once adsorbed, it becomes activated, initiating a cascade of enzymatic reactions that lead to surface-induced coagulation. This process is characterized by multiple redundancies, making it extremely challenging to prevent clot formation and preserve the properties of the surface. In this study, a novel modulatory coating system based on C1-esterase inhibitor (C1INH) functionalized polymer brushes, which effectively regulates the activation of FXII is proposed. Using surface plasmon resonance it is demonstrated that this coating system effectively repels blood plasma proteins, including FXII, while exhibiting high activity against activated FXII and plasma kallikrein under physiological conditions. This unique property enables the modulation of FXII activation without interfering with the overall hemostasis process. Furthermore, through dynamic Chandler loop studies, it is shown that this coating significantly improves the hemocompatibility of polymeric surfaces commonly used in medical devices. By addressing the root cause of contact activation, the synergistic interplay between the antifouling polymer brushes and the modulatory C1INH is expected to lay the foundation to enhance the hemocompatibility of medical device surfaces.© 2023 The Authors. Macromolecular Bioscience published by Wiley-VCH GmbH.

JTD Keywords: adsorption, binding, c1-esterase-inhibitor, coatings, contact activation, factor-xii, fxii activation, hemocompatibility, hemocompatible surface modification, heparin, polymer brushes, system, thrombosis, Adsorption, Anticoagulation, Antifouling agent, Article, Beta-fxiia, Biocompatibility, Blood, Blood clotting, Blood clotting factor 12, Blood clotting factor 12a, Blood clotting factor 12a inhibitor, Blood coagulation, C1-esterase-inhibitor, Cell activation, Chemical activation, Coagulation, Coating (procedure), Complement component c1s inhibitor, Complement system, Controlled study, Dendrimers, Enzyme immobilization, Enzymes, Erythrocyte, Esters, Factor xii, Factor xii activation, Factor xiia, Fibrin deposition, Functional polymers, Fxii activation, Haemocompatibility, Hemocompatibility, Hemocompatible surface modification, Hemostasis, Heparin, Human, Hydrogel, Medical devices, Metabolism, Plasma kallikrein, Plasma protein, Plastic coatings, Platelet count, Polymer, Polymer brushes, Polymerization, Polymers, Property, Root cause, Surface plasmon resonance, Surface property, Surface reactions, Surface-modification, Thrombocyte adhesion, Β-fxiia

Human pluripotent stem cell -derived kidney organoids offer unprecedented opportunities for studying polycystic kidney disease (PKD), which still has no effective cure. Here, we developed both in vitro and in vivo organoid models of PKD that manifested tubular injury and aberrant upregulation of renin-angiotensin aldosterone system. Single -cell analysis revealed that a myriad of metabolic changes occurred during cystogenesis, including defective autophagy. Experimental activation of autophagy via ATG5 overexpression or primary cilia ablation significantly inhibited cystogenesis in PKD kidney organoids. Employing the organoid xenograft model of PKD, which spontaneously developed tubular cysts, we demonstrate that minoxidil, a potent autophagy activator and an FDA -approved drug, effectively attenuated cyst formation in vivo. This in vivo organoid model of PKD will enhance our capability to discover novel disease mechanisms and validate candidate drugs for clinical translation.

JTD Keywords: Adenylate kinase, Adult, Animal cell, Animal experiment, Animal model, Animal tissue, Article, Autophagosome, Autophagy, Autophagy (cellular), Autosomal-dominant, Calcium homeostasis, Cilia, Cilium, Cohort analysis, Controlled study, Cyclic amp, Disease, Dominant polycystic kidney, Enzyme linked immunosorbent assay, Epithelium, Exon, Expression, Female, Food and drug administration, Framework, Generation, Growth, Hepatitis a virus cellular receptor 1, Human, Human cell, Humans, Immunohistochemistry, In vitro study, In vivo study, Kidney, Kidney organoid, Kidney polycystic disease, Male, Minoxidil, Mouse, Mutations, Nonhuman, Organoid, Organoids, Platelet derived growth factor beta receptor, Pluripotent stem-cells, Polycystic kidney diseases, Protein kinase lkb1, Renin, Sequestosome 1, Single cell analysis, Single cell rna seq, Small nuclear rna, Tunel assay, Upregulation, Western blotting, Whole exome sequencing

ASM deficiency in Niemann-Pick disease type A results in aberrant cellular accumulation of sphingomyelin, neuroinflammation, neurodegeneration, and early death. There is no available treatment because enzyme replacement therapy cannot surmount the blood-brain barrier (BBB). Nanocarriers (NCs) targeted across the BBB via transcytosis might help; yet, whether ASM deficiency alters transcytosis remains poorly characterized. We investigated this using model NCs targeted to intracellular adhesion molecule-1 (ICAM-1), transferrin receptor (TfR), or plasmalemma vesicle-associated protein-1 (PV1) in ASM-normal vs. ASM-deficient BBB models. Disease differentially changed the expression of all three targets, with ICAM-1 becoming the highest. Apical binding and uptake of anti-TfR NCs and anti-PV1 NCs were unaffected by disease, while anti-ICAM-1 NCs had increased apical binding and decreased uptake rate, resulting in unchanged intracellular NCs. Additionally, anti-ICAM-1 NCs underwent basolateral reuptake after transcytosis, whose rate was decreased by disease, as for apical uptake. Consequently, disease increased the effective transcytosis rate for anti-ICAM-1 NCs. Increased transcytosis was also observed for anti-PV1 NCs, while anti-TfR NCs remained unaffected. A fraction of each formulation trafficked to endothelial lysosomes. This was decreased in disease for anti-ICAM-1 NCs and anti-PV1 NCs, agreeing with opposite transcytosis changes, while it increased for anti-TfR NCs. Overall, these variations in receptor expression and NC transport resulted in anti-ICAM-1 NCs displaying the highest absolute transcytosis in the disease condition. Furthermore, these results revealed that ASM deficiency can differently alter these processes depending on the particular target, for which this type of study is key to guide the design of therapeutic NCs.© 2023. Controlled Release Society.

JTD Keywords: asm deficiency, blood-brain barrier, delivery, determines, drug, endocytosis, enzymes, icam-1, lysosomal storage disease, mechanisms, nanoparticles, natural-history, niemann-pick disease type a, pv-1, receptor-mediated transcytosis, trafficking, transferrin receptor, Asm deficiency, Blood-brain barrier, Blood–brain barrier, Drug carriers, Drug nanocarriers, Humans, Icam-1, Icam-1-targeted nanocarriers, Intercellular adhesion molecule-1, Lysosomal storage disease, Niemann-pick disease type a, Niemann-pick disease, type a, Niemann-pick diseases, Pv-1, Receptor-mediated transcytosis, Transferrin receptor

Naso- and oropharyngeal swabs are the Center for Disease Control and Prevention (CDC) -recommended disease sampling methods for respiratory viruses. The short swabbing time for sampling by these methods may lead to variability in test results. Further, these methods are mildly invasive and can cause discomfort, tearing or gag reflexes in tested individuals. If longer sampling time is coupled with lesser patient discomfort, test reliability and patient compliance can be improved. Towards this end, we developed cationic biopolymer membranes for the electrostatic capturing of viruses in the oral cavity. Here, chemically (EDC-NHS) crosslinked uncharged chitosan (CS) nanofiber membranes were conferred either with negative surface charge by anionic poly-aspartic acid (pAsp) coating or positive charge by cationic poly-L-lysine (PLL). Consistent with our preliminary findings of dynamic light scattering (DLS) size measurements showing large agglomerates of anionic virus-like particles (VLPs) and cationic PLL in solution, a 75% increase in VLP adsorption by PLL coated CS membranes was recorded by enzyme linked immunosorbent assay (ELISA), in comparison to untreated controls. It is envisaged that the electrostatic concentration of respiratory viruses on cationic membranes can be superior alternatives to traditional swabbing in the oral cavity.

JTD Keywords: Cationic biopolymer membranes, Disease sampling, Dynamic light scattering (dls), Electrostatic capture of viruses, Enzyme linked immunosorbent assay (elisa), Magnetic beads, Virus -like particles (vlps)

Prior studies demonstrated that encapsulation in poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) enhanced the delivery of enzymes used for replacement therapy (ERT) of lysosomal storage disorders (LSDs). This study examined how the copolymer lactide:glycolide ratio impacts encapsulation, physicochemical characteristics, stability, and release under lysosomal conditions. Hyaluronidase, deficient in mucopolysaccharidosis IX, was encapsulated in NPs synthesized using 50:50, 60:40, or 75:25 lactide:glycolide copolymers. All NPs had diameters compatible with cellular transport (≤168 nm) and polydispersity indexes (≤0.16) and ζ-potentials (≤-35 mV) compatible with colloidal stability. Yet, their encapsulation efficiency varied, with 75:25 NPs and 60:40 NPs having the lowest and highest EE, respectively (15% vs. 28%). Under lysosomal conditions, the 50:50 copolymer degraded fastest (41% in 1 week), as expected, and the presence of a targeting antibody coat did not alter this result. Additionally, 60:40 NPs destabilized fastest (<1 week) because of their smaller diameter, and 75:25 NPs did not destabilize in 4 weeks. All formulations presented burst release under lysosomal conditions (56-78% of the original load within 30 min), with 50:50 and 60:40 NPs releasing an additional small fraction after week 1. This provided 4 weeks of sustained catalytic activity, sufficient to fully degrade a substrate. Altogether, the 60:40 NP formulation is preferred given its higher EE, and 50:50 NPs represent a valid alternative, while the highest stability of 75:25 NPs may impair lysosomes. These results can guide future studies aiming to translate PLGA NP-based ERT for this and other LSDs.

JTD Keywords: biodegradation, copolymer ratio, degradation, drug-delivery, emulsification, enzyme release, enzyme replacement therapy, hyaluronidase, mechanisms, microspheres, nanoparticle stability, poly(lactide-co-glycolide) nanoparticles, size, sphingomyelinase, transport, Central-nervous-system, Copolymer ratio, Enzyme release, Enzyme replacement therapy, Hyaluronidase, Lysosomal storage disorder, Nanoparticle stability, Poly(lactide-co-glycolide) nanoparticles

The present study investigated early interactions between three alloplastic materials (calcium phosphate (CaP), titanium alloy (Ti), and polyetheretherketone (PEEK) with human whole blood using an established in vitro slide chamber model. After 60 min of contact with blood, coagulation (thrombin-antithrombin complexes, TAT) was initiated on all test materials (Ti > PEEK > CaP), with a significant increase only for Ti. All materials showed increased contact activation, with the KK-AT complex significantly increasing for CaP (p < 0.001), Ti (p < 0.01), and PEEK (p < 0.01) while only CaP demonstrated a notable rise in KK-C1INH production (p < 0.01). The complement system had significant activation across all materials, with CaP (p < 0.0001, p < 0.0001) generating the most pronounced levels of C3a and sC5b-9, followed by Ti (p < 0.001, p < 0.001) and lastly, PEEK (p < 0.001, p < 0.01). This activation correlated with leukocyte stimulation, particularly myeloperoxidase release. Consequently, the complement system may assume a more significant role in the early stages post implantation in response to CaP materials than previously recognized. Activation of the complement system and the inevitable activation of leukocytes might provide a more favorable environment for tissue remodeling and repair than has been traditionally acknowledged. While these findings are limited to the early blood response, complement and leukocyte activation suggest improved healing outcomes, which may impact long-term clinical outcomes.

JTD Keywords: activation, biomaterial, calcium phosphate, coagulation, complement, cranioplasty, human whole blood, platelets, receptors, surface, titanium, Biomaterials, Calcium phosphate, Coagulation, Complement, Human whole blood, Peroxidase enzymes

Lysosomes play a central role in cellular homeostasis and alterations in this compartment associate with many diseases. The most studied example is that of lysosomal storage disorders (LSDs), a group of 60 + maladies due to genetic mutations affecting lysosomal components, mostly enzymes. This leads to aberrant intracellular storage of macromolecules, altering normal cell function and causing multiorgan syndromes, often fatal within the first years of life. Several treatment modalities are available for a dozen LSDs, mostly consisting of enzyme replacement therapy (ERT) strategies. Yet, poor biodistribution to main targets such as the central nervous system, musculoskeletal tissue, and others, as well as generation of blocking antibodies and adverse effects hinder effective LSD treatment. Drug delivery systems are being studied to surmount these obstacles, including polymeric constructs and nanoparticles that consti-tute the focus of this article. We provide an overview of the formulations being tested, the diseases they aim to treat, and the results observed from respective in vitro and in vivo studies. We also discuss the advantages and disadvantages of these strategies, the remaining gaps of knowledge regarding their per-formance, and important items to consider for their clinical translation. Overall, polymeric nanocon-structs hold considerable promise to advance treatment for LSDs.(c) 2023 Elsevier B.V. All rights reserved.

JTD Keywords: cellular and animal models, enzyme replacement therapy, lysosomal storage disorders, nanoemulsions, nanoparticles, Beta-glucuronidase deficiency, Blood-brain-barrier, Cellular and animal models, Central-nervous-system, Drug delivery systems, Enzyme replacement therapy, Feline gm1 gangliosidosis, Human acid sphingomyelinase, Human alpha-galactosidase, Humans, Lysosomal storage diseases, Lysosomal storage disorders, Lysosomes, Mucopolysaccharidosis type-ii, Nanoemulsions, Nanoparticles, Neuronal ceroid-lipofuscinosis, Niemann-pick-disease, Pluripotent stem-cells, Polymer-based drug delivery systems, Polymers, Tissue distribution

Targeted drug delivery depends on the ability of nanocarriers to reach the target site, which requires the penetration of different biological barriers. Penetration is usually low and slow because of passive diffusion and steric hindrance. Nanomotors (NMs) have been suggested as the next generation of nanocarriers in drug delivery due to their autonomous motion and associated mixing hydrodynamics, especially when acting collectively as a swarm. Here, we explore the concept of enzyme-powered NMs designed as such that they can exert disruptive mechanical forces upon laser irradiation. The urease-powered motion and swarm behavior improve translational movement compared to passive diffusion of state-of-the-art nanocarriers, while optically triggered vapor nanobubbles can destroy biological barriers and reduce steric hindrance. We show that these motors, named Swarm 1, collectively displace through a microchannel blocked with type 1 collagen protein fibers (barrier model), accumulate onto the fibers, and disrupt them completely upon laser irradiation. We evaluate the disruption of the microenvironment induced by these NMs (Swarm 1) by quantifying the efficiency by which a second type of fluorescent NMs (Swarm 2) can move through the cleared microchannel and be taken up by HeLa cells at the other side of the channel. Experiments showed that the delivery efficiency of Swarm 2 NMs in a clean path was increased 12-fold in the presence of urea as fuel compared to when no fuel was added. When the path was blocked with the collagen fibers, delivery efficiency dropped considerably and only depicted a 10-fold enhancement after pretreatment of the collagen-filled channel with Swarm 1 NMs and laser irradiation. The synergistic effect of active motion (chemically propelled) and mechanical disruption (light-triggered nanobubbles) of a biological barrier represents a clear advantage for the improvement of therapies which currently fail due to inadequate passage of drug delivery carriers through biological barriers.

JTD Keywords: drug delivery, enzyme catalysis, nanoparticles, swarming, vapor nanobubbles, Drug carriers, Drug delivery, Drug delivery systems, Enzyme catalysis, Hela cells, Humans, Nanomotors, Nanoparticles, Swarming, Vapor nanobubbles

Lafora disease is a rare disorder caused by loss of function mutations in either the EPM2A or NHLRC1 gene. The initial symptoms of this condition are most commonly epileptic seizures, but the disease progresses rapidly with dementia, neuropsychiatric symptoms, and cognitive deterioration and has a fatal outcome within 5–10 years after onset. The hallmark of the disease is the accumulation of poorly branched glycogen in the form of aggregates known as Lafora bodies in the brain and other tissues. Several reports have demonstrated that the accumulation of this abnormal glycogen underlies all the pathologic traits of the disease. For decades, Lafora bodies were thought to accumulate exclusively in neurons. However, it was recently identified that most of these glycogen aggregates are present in astrocytes. Importantly, astrocytic Lafora bodies have been shown to contribute to pathology in Lafora disease. These results identify a primary role of astrocytes in the pathophysiology of Lafora disease and have important implications for other conditions in which glycogen abnormally accumulates in astrocytes, such as Adult Polyglucosan Body disease and the buildup of Corpora amylacea in aged brains.

JTD Keywords: abnormal glycogen, accumulation, aggregation, bodies, branching enzyme deficiency, corpora-amylacea, epilepsy, glycogen, lafora disease, mice, mouse model, neurodegeneration, neuroinflammation, progressive myoclonus epilepsy, ubiquitin ligase, Glycogen, Neuroinflammation, Polyglucosan body disease

Although an increasing number of micro/nanomotors have been designed for environmental remediation in the past decade, the construction of contaminants-fueled nanomotors for synergistically degrading multiple pollutants simultaneously remains a challenge. Herein, laccase-powered Fe3O4@silica nanomotors are fabricated, assisted with lipase enzyme for the enhanced degradation of multiple contaminants using the contaminants themselves as fuels. Notably, we demonstrate that representative industrial phenols and polycyclic aromatic pollutants possess the ability of triggering the enhanced Brownian motion of laccase nanomotors (De of 1.16 mu m(2)/s in 220 mu M biphenol A (BPA), 1.40 mu m(2)/s in 375 mu M Congo red (CR)). Additionally, the k(cat) value of lipase-assisted laccase-powered nanomotors increased over 1.4 times, enhancing their Brownian motion, while leading to the efficient degradation of multiple contaminants such as BPA, CR, and triacetin droplets within 40 min, simultaneously. Ultimately, the lipase-assisted laccase nanomotors exhibit great advantages over free laccase, free lipase, lipase nanomotors, or laccase nanomotors in K-m, k(cat), catalytic stability, recycling property, and the degradation efficiency of contaminants. Therefore, our work further broadens the library of enzyme-powered nanomotors and provides deep insights in synergistical enzymatic catalysis, thus paving avenues for environmental remediation based on enzyme-powered micro/nanomotors. (C) 2022 Elsevier Ltd. All rights reserved.

JTD Keywords: core, dye, environmental remediation, enzyme catalysis, hybrid, light, microspheres, motors, pollutants removal, propulsion, removal, self-propulsion, shell, Core, Dye, Environmental remediation, Enzyme catalysis, Hybrid, Light, Micro/nanomotors, Micromotors, Microspheres, Motors, Pollutants removal, Propulsion, Removal, Self-propulsion, Shell

This work aimed at the antimicrobial functionalization of 3D-printed polymer-infiltrated biomimetic ceramic networks (PICN). The anti-microbial properties of the polymer-ceramic composites were achieved by coating them with human-and environmentally safe silver nanoparticles trapped in a phenolated lignin matrix (Ag@PL NPs). Lignin was enzymatically phenolated and used as a biobased reducing agent to obtain stable Ag@PL NPs, which were then formulated in a silane (gamma-MPS) solution and deposited to the PICN surface. The presence of the NPs and their proper attachment to the surface were analyzed with spectroscopic methods (FTIR and Raman) and X-ray photoelectron spectroscopy (XPS). Homogeneous distribution of 13.4 +/- 3.2 nm NPs was observed in the transmission electron microscopy (TEM) images. The functionalized samples were tested against Gram-positive (Staphylococcus aureus) and Gram-negative (Pseudomonas aeruginosa) bacteria, validating their antimicrobial efficiency in 24 h. The bacterial reduction of S. aureus was 90% in comparison with the pristine surface of PICN. To confirm that the Ag-functionalized PICN scaffold is a safe material to be used in the biomedical field, its biocompatibility was demonstrated with human fibroblast (BJ-5ta) and keratinocyte (HaCaT) cells, which was higher than 80% in both cell lines.

JTD Keywords: accuracy, antibacterial activity, disease, facile, laccase enzyme, lignin, polyacrylates, polymer-infiltrated ceramic network, silver nanoparticles, zirconia, Mechanical-properties, Mechanical-properties,zirconia,lignin,accuracy,disease,facil, Polymer-infiltrated ceramic network, Polymer-infiltrated ceramic network,polyacrylates,lignin,laccase enzyme,silver nanoparticles,antibacterial activit, Silver nanoparticles

The recent emergence of multiple SARS-CoV-2 variants has caused considerable concern due to both reduced vaccine efficacy and escape from neutralizing antibody therapeutics. It is, therefore, paramount to develop therapeutic strategies that inhibit all known and future SARS-CoV-2 variants. Here, we report that all SARS-CoV-2 variants analyzed, including variants of concern (VOC) Alpha, Beta, Gamma, Delta, and Omicron, exhibit enhanced binding affinity to clinical grade and phase 2 tested recombinant human soluble ACE2 (APN01). Importantly, soluble ACE2 neutralized infection of VeroE6 cells and human lung epithelial cells by all current VOC strains with markedly enhanced potency when compared to reference SARS-CoV-2 isolates. Effective inhibition of infections with SARS-CoV-2 variants was validated and confirmed in two independent laboratories. These data show that SARS-CoV-2 variants that have emerged around the world, including current VOC and several variants of interest, can be inhibited by soluble ACE2, providing proof of principle of a pan-SARS-CoV-2 therapeutic.

JTD Keywords: clinical trial, covid-19, treatment, Clinical trial, Converting enzyme 2, Covid-19, Spike, Treatment, Vaccine

It is not well understood why diabetic individuals are more prone to develop severe COVID-19. To this, we here established a human kidney organoid model promoting early hallmarks of diabetic kidney disease development. Upon SARS-CoV-2 infection, diabetic-like kidney organoids exhibited higher viral loads compared with their control counterparts. Genetic deletion of the angiotensin-converting enzyme 2 (ACE2) in kidney organoids under control or diabetic-like conditions prevented viral detection. Moreover, cells isolated from kidney biopsies from diabetic patients exhibited altered mitochondrial respiration and enhanced glycolysis, resulting in higher SARS-CoV-2 infections compared with non-diabetic cells. Conversely, the exposure of patient cells to dichloroacetate (DCA), an inhibitor of aerobic glycolysis, resulted in reduced SARS-CoV-2 infections. Our results provide insights into the identification of diabetic-induced metabolic programming in the kidney as a critical event increasing SARS-CoV-2 infection susceptibility, opening the door to the identification of new interventions in COVID-19 pathogenesis targeting energy metabolism.Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.

JTD Keywords: complications, coronavirus, cultured-cells, disease, distal tubule, mouse, protein, reveals, spike, Ace2, Angiotensin-converting enzyme 2, Angiotensin-converting enzyme-2, Covid-19, Diabetes 2, Human kidney organoids, Sars-cov-2

The influence of the properties of different solid substrates on the tethering of two antibodies, IgG1-CR3022 and IgG1-S309, which were specifically engineered for the detection of SARS-CoV-2, has been examined at the molecular level using conventional and accelerated Molecular Dynamics (cMD and aMD, respectively). Two surfaces with very different properties and widely used in immunosensors for diagnosis, amorphous silica and the most stable facet of the face-centered cubic gold structure, have been considered. The effects of such surfaces on the structure and orientation of the immobilized antibodies have been determined by quantifying the tilt and hinge angles that describe the orientation and shape of the antibody, respectively, and the dihedrals that measure the relative position of the antibody arms with respect to the surface. Results show that the interactions with amorphous silica, which are mainly electrostatic due to the charged nature of the surface, help to preserve the orientation and structure of the antibodies, especially of the IgG1-CR3022, indicating that the primary sequence of those antibodies also plays some role. Instead, short-range van der Waals interactions with the inert gold surface cause a higher degree tilting and fraying of the antibodies with respect to amorphous silica. The interactions between the antibodies and the surface also affect the correlation among the different angles and dihedrals, which increases with their strength. Overall, results explain why amorphous silica substrates are frequently used to immobilize antibodies in immunosensors. © 2022 The Authors

JTD Keywords: amorphous silica, antibody immobilization, enzyme, gol d, gold, immobilization, immunosensor, molecu l a r dynamics, molecular dynamics, protein adsorption, sars-cov-2 immunosensor, simulations, spike protein, surface interactions, target, vaccine, Amorphous silica, Antibodies, Antibody engineering, Antibody immobilization, Antibody structure, Article, Chemical detection, Computer model, Controlled study, Dihedral angle, Gold, In-silico, Molecular dynamics, Molecular levels, Molecular-dynamics, Nonhuman, Property, Sars, Sars-cov-2 immunosensor, Severe acute respiratory syndrome coronavirus 2, Silica, Silico studies, Silicon dioxide, Solid substrates, Structure analysis, Substrate chemistry, Substrates, Van der waals forces, Virus detection

Poly(lactide-co-glycolide) (PLGA) nanoparticles (NPs) enhance the delivery of therapeutic enzymes for replacement therapy of lysosomal storage disorders. Previous studies examined NPs encapsulating or coated with enzymes, but these formulations have never been compared. We examined this using hyaluronidase (HAse), deficient in mucopolysaccharidosis IX, and acid sphingomyelinase (ASM), deficient in types A–B Niemann–Pick disease. Initial screening of size, PDI, ζ potential, and loading resulted in the selection of the Lactel II co-polymer vs. Lactel I or Resomer, and Pluronic F68 surfactant vs. PVA or DMAB. Enzyme input and addition of carrier protein were evaluated, rendering NPs having, e.g., 181 nm diameter, 0.15 PDI, −36 mV ζ potential, and 538 HAse molecules encapsulated per NP. Similar NPs were coated with enzyme, which reduced loading (e.g., 292 HAse molecules/NP). NPs were coated with targeting antibodies (> 122 molecules/NP), lyophilized for storage without alterations, and acceptably stable at physiological conditions. NPs were internalized, trafficked to lysosomes, released active enzyme at lysosomal conditions, and targeted both peripheral organs and the brain after i.v. administration in mice. While both formulations enhanced enzyme delivery compared to free enzyme, encapsulating NPs surpassed coated counterparts (18.4- vs. 4.3-fold enhancement in cells and 6.2- vs. 3-fold enhancement in brains), providing guidance for future applications.

JTD Keywords: active enzymes, encapsulation, enhanced delivery, enzyme therapeutics, formulation parameters, icam-1 targeting, icam-1-targeted nanocarriers, in vivo biodistribution, in-vitro, lysosomal delivery, model, oral delivery, plga nanoparticles, poly(lactic-co-glycolic acid) nanoparticles, protein therapeutics, surface loading, Acid sphingomyelinase, Enzyme therapeutics, Surface loading

Enzyme-powered micro- and nanomotors make use of biocatalysis to self-propel in aqueous media and hold immense promise for active and targeted drug delivery. Most (if not all) of these micro- and nanomotors described to date are fabricated using a commercially available enzyme, despite claims that some commercial preparations may not have a sufficiently high degree of purity for downstream applications. In this study, the purity of a commercial urease, an enzyme frequently used to power the motion of micro- and nanomotors, was evaluated and found to be impure. After separating the hexameric urease from the protein impurities by size-exclusion chromatography, the hexameric urease was subsequently characterized and used to functionalize hollow silica microcapsules. Micromotors loaded with purified urease were found to be 2.5 times more motile than the same micromotors loaded with unpurified urease, reaching average speeds of 5.5 ?m/s. After comparing a number of parameters, such as enzyme distribution, protein loading, and motor reusability, between micromotors functionalized with purified vs unpurified urease, it was concluded that protein purification was essential for optimal performance of the enzyme-powered micromotor.

JTD Keywords: canavalin, catalysis, delivery, dls, enhanced diffusion, enzyme, lipase immobilization, micromotors, self-propulsion, super-resolution microscopy, urease, Mesoporous silica nanoparticles, Micromotors, Super-resolution microscopy

Despite tremendous progress in the understanding of COVID-19, mechanistic insight into immunological, disease-driving factors remains limited. We generated maVie16, a mouse-adapted SARS-CoV-2, by serial passaging of a human isolate. In silico modeling revealed how only three Spike mutations of maVie16 enhanced interaction with murine ACE2. maVie16 induced profound pathology in BALB/c and C57BL/6 mice, and the resulting mouse COVID-19 (mCOVID-19) replicated critical aspects of human disease, including early lymphopenia, pulmonary immune cell infiltration, pneumonia, and specific adaptive immunity. Inhibition of the proinflammatory cyto-kines IFN? and TNF substantially reduced immunopathology. Importantly, genetic ACE2-deficiency completely prevented mCOVID-19 development. Finally, inhalation therapy with recombinant ACE2 fully protected mice from mCOVID-19, revealing a novel and efficient treatment. Thus, we here present maVie16 as a new tool to model COVID-19 for the discovery of new therapies and show that disease severity is determined by cytokine-driven immunopathology and critically dependent on ACE2 in vivo. © Gawish et al.

JTD Keywords: covid-19 mouse model, covid-19 therapy, cytokine storm, immunology, inflammation, mavie16, mouse, mouse-adapted sars-cov-2, program, recombinant soluble ace2, tmprss2, Adaptive immunity, Angiotensin converting enzyme 2, Angiotensin-converting enzyme 2, Animal, Animal cell, Animal experiment, Animal model, Animal tissue, Animals, Apoptosis, Article, Bagg albino mouse, Breathing rate, Bronchoalveolar lavage fluid, C57bl mouse, Cell composition, Cell infiltration, Controlled study, Coronavirus disease 2019, Coronavirus spike glycoprotein, Covid-19, Cytokeratin 18, Cytokine production, Dipeptidyl carboxypeptidase, Disease model, Disease models, animal, Disease severity, Drosophila-melanogaster, Enzyme linked immunosorbent assay, Expression vector, Flow cytometry, Gamma interferon, Gene editing, Gene expression, Gene mutation, Genetic engineering, Genetics, Glycosylation, High mobility group b1 protein, Histology, Histopathology, Immune response, Immunocompetent cell, Immunology, Immunopathology, Interferon-gamma, Interleukin 2, Metabolism, Mice, inbred balb c, Mice, inbred c57bl, Mouse-adapted sars-cov-2, Myeloperoxidase, Neuropilin 1, Nonhuman, Nucleocapsid protein, Pathogenicity, Peptidyl-dipeptidase a, Pyroptosis, Recombinant soluble ace2, Renin angiotensin aldosterone system, Rna extraction, Rna isolation, Sars-cov-2, Severe acute respiratory syndrome coronavirus 2, Spike glycoprotein, coronavirus, T lymphocyte activation, Trabecular meshwork, Tumor necrosis factor, Virology, Virus load, Virus replication, Virus transmission, Virus virulence

© 2021 Introduction: Natural products of pharmaceutical interest often do not reach the drug market due to the associated low yields and difficult extraction. Knowledge of biosynthetic pathways is a key element in the development of biotechnological strategies for plant specialized metabolite production. The scarce studies regarding non-model plants impair advances in this field. Erythrina spp. are mainly used as central nervous system depressants in folk medicine and are important sources of bioactive tetracyclic benzylisoquinoline alkaloids, which can act on several pathology-related biological targets. Objective: Herein the purpose is to employ combined transcriptome and metabolome analyses (seeds and leaves) of a non-model medicinal Fabaceae species grown in its unique arid natural habitat. The study tries to propose a putative biosynthetic pathway for the bioactive alkaloids by using an omic integrated approach. Methods: The Next Generation Sequencing-based transcriptome (de novo RNA sequencing) was carried out in a Illumina NextSeq 500 platform. Regarding the targeted metabolite profiling, Nuclear Magnetic Resonance and the High-Performance Liquid Chromatography coupled to a micrOTOF-QII, High Resolution Mass Spectrometer, were used. Results: This detailed macro and micromolecular approach applied to seeds and leaves of E. velutina revealed 42 alkaloids by metabolome tools. Based on the combined evidence, 24 gene candidates were put together in a putative pathway leading to the singular alkaloid diversity of this species. Conclusion: These results contribute by indicating potential biotechnological targets Erythrina alkaloids biosynthesis as well as to improve molecular databases with omic data from a non-model medicinal plant. Furthermore, they reveal an interesting chemical diversity in Erythrina velutina harvested in Caatinga. Last, but not least, this data may also contribute to tap Brazilian biodiversity in a rational and sustainable fashion, promoting adequate public policies for preservation and protection of sensitive areas within the Caatinga.

JTD Keywords: benzylisoquinoline alkaloids, caatinga, codeinone reductase, erythrina velutina, expression, mass-spectrometry, molecular-cloning, morphine biosynthesis, natural-products, opium poppy, papaver-somniferum, plant-metabolism, targeted metabolite profile, transcriptome, Benzylisoquinoline alkaloids, Berberine bridge enzyme, Caatinga, Erythrina velutina, Targeted metabolite profile, Transcriptome

Contact-based antimicrobials, as antibiotic-free technologies that use non-specific interactions with bacterial cells to exert antimicrobial activity, are a prospective solution in fighting the global issue of bacterial resistance. A very simplified approach to their design considers the direct bonding of cationic guanidine-containing amino acids to the surface of nano-gold carriers. The structure enables antimicrobial activity due to a high density of cationic surface charges. This opens a set of novel questions that are important for their effective engineering, particularly regarding (i) chemistry and events that take place at the interface between NPs and cells, (ii) the direct influence of a charge (and its change) on interactions with bacterial and mammalian cells, and (iii) the stability of structures (and their antimicrobial activity) in the presence of enzymes, which are addressed in this paper. Because of the ability of amino acid-functionalized nano-gold to retain structural and functional activity, even after exposure to a range of physicochemical stimuli, they provide an excellent nanotechnological platform for designing highly effective contact-based antimicrobials and their applications.

JTD Keywords: agents, antibiotic-free technology, arginine, charged amino acids, contact-based antimicrobials, discovery, enzyme-resistant antimicrobials, functionalized gold, peptides, polymers, resistant, Antibiotic-free technology, Charged amino acids, Contact-based antimicrobials, Enzyme-resistant antimicrobials, Functionalized gold, Nanoparticles

The generation of kidney organoids from human pluripotent stem cells (hPSCs) has represented a relevant scientific achievement in the organoid field. Importantly, hPSC-derived kidney organoids contain multiple nephron-like structures that exhibit some renal functional characteristics and have the capacity to respond to nephrotoxic agents. In this review, we first discuss how bioengineering approaches can help overcome current kidney organoid challenges. Next, we focus on recent works exploiting kidney organoids for drug screening and disease modeling applications. Finally, we provide a state of the art on current research toward the potential application of kidney organoids and renal cells derived from hPSCs for future renal replacement therapies.

JTD Keywords: Bioengineering, Converting enzyme-ii, Crispr/cas9 gene editing, Disease, Disease modeling, Extracellular-matrix, Generation, Human pluripotent stem cells, Kidney organoids, Kidney regeneration, Model, Mouse, Reveals, Scaffold, Transplantation

Here the authors develop a coacervate micromotor that can display autonomous motion as a result of stochastic distribution of propelling units. This stochastic-induced mobility is validated and explained through experiments and theory. Random fluctuations are inherent to all complex molecular systems. Although nature has evolved mechanisms to control stochastic events to achieve the desired biological output, reproducing this in synthetic systems represents a significant challenge. Here we present an artificial platform that enables us to exploit stochasticity to direct motile behavior. We found that enzymes, when confined to the fluidic polymer membrane of a core-shell coacervate, were distributed stochastically in time and space. This resulted in a transient, asymmetric configuration of propulsive units, which imparted motility to such coacervates in presence of substrate. This mechanism was confirmed by stochastic modelling and simulations in silico. Furthermore, we showed that a deeper understanding of the mechanism of stochasticity could be utilized to modulate the motion output. Conceptually, this work represents a leap in design philosophy in the construction of synthetic systems with life-like behaviors.

JTD Keywords: Cell, Cell component, Enzyme, Enzyme activity, Membrane, Philosophy, Polymer, Stochasticity, Substrate

Bioremediation with immobilized enzymes has several advantages, such as the enhancement of selectivity, activity, and stability of biocatalysts, as well as enzyme reusability. Laccase has proven to be a good candidate for the removal of a wide range of contaminants. In this study, naked or modified MnFe O magnetic nanoparticles (MNPs) were used as supports for the immobilization of laccase from Trametes versicolor. To increase enzyme loading and stability, MNPs were coated with chitosan both after the MNP synthesis (MNPs-CS) and during their formation (MNPs-CS ). SEM analysis showed different sizes for the two coated systems, 20 nm and 10 nm for MNPs-CS and MNPs-CS , respectively. After covalent immobilization of laccase by glutaraldehyde, the MNPs-CS -lac and MNPs-CS-lac systems showed a good resistance to temperature denaturation and storage stability. The most promising system for use in repeated batches was MNPs-CS -lac, which degraded about 80% of diclofenac compared to 70% of the free enzyme. The obtained results demonstrated that the MnFe O -CS system could be an excellent candidate for the removal of contaminants. 2 4 in situ in situ in situ in situ 2 4 in situ

JTD Keywords: bioremediation, chitosan, diclofenac, diclofenac removal, immobilized enzyme, laccase, magnetic nanoparticles, phase, removal, supports, Bioremediation, Chitosan, Diclofenac removal, Enzyme immobilization, Immobilized enzyme, Laccase, Magnetic nanoparticles

In the present study the use of extracellular vesicles (EVs) as vehicles for therapeutic enzymes in lysosomal storage disorders was explored. EVs were isolated from mammalian cells overexpressing alpha-galactosidase A (GLA) or N-sulfoglucosamine sulfohydrolase (SGSH) enzymes, defective in Fabry and Sanfilippo A diseases, respectively. Direct purification of EVs from cell supernatants was found to be a simple and efficient method to obtain highly active GLA and SGSH proteins, even after EV lyophilization. Likewise, EVs carrying GLA (EV-GLA) were rapidly uptaken and reached the lysosomes in cellular models of Fabry disease, restoring lysosomal functionality much more efficiently than the recombinant enzyme in clinical use. In vivo, EVs were well tolerated and distributed among all main organs, including the brain. DiR-labelled EVs were localized in brain parenchyma 1 h after intra-arterial (internal carotid artery) or intravenous (tail vein) administrations. Moreover, a single intravenous administration of EV-GLA was able to reduce globotriaosylceramide (Gb3) substrate levels in clinically relevant tissues, such kidneys and brain. Overall, our results demonstrate that EVs from cells overexpressing lysosomal enzymes act as natural protein delivery systems, improving the activity and the efficacy of the recombinant proteins and facilitating their access to organs neglected by conventional enzyme replacement therapies.

JTD Keywords: alpha?galactosidase a, alpha‐galactosidase a, drug delivery, enzyme replacement therapy, fabry disease, lysosomal storage disorders, n-sulfoglucosamine sulfohydrolase, n?sulfoglucosamine sulfohydrolase, n‐sulfoglucosamine sulfohydrolase, sanfilippo syndrome, Alpha-galactosidase a, Drug delivery, Enzyme replacement therapy, Fabry disease, Lysosomal storage disorders, N-sulfoglucosamine sulfohydrolase, Sanfilippo syndrome

We have previously provided the first genetic evidence that angiotensin converting enzyme 2 (ACE2) is the critical receptor for severe acute respiratory syndrome coronavirus (SARS-CoV), and ACE2 protects the lung from injury, providing a molecular explanation for the severe lung failure and death due to SARS-CoV infections. ACE2 has now also been identified as a key receptor for SARS-CoV-2 infections, and it has been proposed that inhibiting this interaction might be used in treating patients with COVID-19. However, it is not known whether human recombinant soluble ACE2 (hrsACE2) blocks growth of SARS-CoV-2. Here, we show that clinical grade hrsACE2 reduced SARS-CoV-2 recovery from Vero cells by a factor of 1,000-5,000. An equivalent mouse rsACE2 had no effect. We also show that SARS-CoV-2 can directly infect engineered human blood vessel organoids and human kidney organoids, which can be inhibited by hrsACE2. These data demonstrate that hrsACE2 can significantly block early stages of SARS-CoV-2 infections.

JTD Keywords: COVID-19, Angiotensin converting enzyme 2, Blood vessels, Human organoids, Kidney, Severe acute respiratory syndrome coronavirus, Spike glycoproteins, Treatment

We report lipase-based nanomotors that are capable of enhanced Brownian motion over long periods of time in triglyceride solution and of degrading triglyceride droplets that mimic “blood lipids”. We achieved about 40 min of enhanced diffusion of lipase-modified mesoporous silica nanoparticles (MSNPs) through a biocatalytic reaction between lipase and its corresponding water-soluble oil substrate (triacetin) as fuel, which resulted in an enhanced diffusion coefficient (ca. 50 % increase) at low triacetin concentration (<10 mm). Lipase not only serves as the power engine but also as a highly efficient cleaner for the triglyceride droplets (e.g., tributyrin) in PBS solution, which could yield potential biomedical applications, for example, for dealing with diseases related to the accumulation of triglycerides, or for environmental remediation, for example, for the degradation of oil spills.

JTD Keywords: Enzyme nanomotors, Lipase, Micromotors, Oil removal, Self-propulsion

Bio-catalytic micro- and nanomotors self-propel by the enzymatic conversion of substrates into products. Despite the advances in the field, the fundamental aspects underlying enzyme-powered self-propulsion have rarely been studied. In this work, we select four enzymes (urease, acetylcholinesterase, glucose oxidase, and aldolase) to be attached on silica microcapsules and study how their turnover number and conformational dynamics affect the self-propulsion, combining both an experimental and molecular dynamics simulations approach. Urease and acetylcholinesterase, the enzymes with higher catalytic rates, are the only enzymes capable of producing active motion. Molecular dynamics simulations reveal that urease and acetylcholinesterase display the highest degree of flexibility near the active site, which could play a role on the catalytic process. We experimentally assess this hypothesis for urease micromotors through competitive inhibition (acetohydroxamic acid) and increasing enzyme rigidity (β-mercaptoethanol). We conclude that the conformational changes are a precondition of urease catalysis, which is essential to generate self-propulsion.

JTD Keywords: Biocatalysis, Immobilized enzymes, Molecular machines and motors

Enzyme triggered bio-catalytic reactions convert chemical energy into mechanical force to power micro/nano-machines. Though there have been reports about enzymes powered micro/nano-motors, enzymatic Janus nano-motor smaller than 100 nm has not been reported yet. Here, we prepared an enzyme powered Janus nano-motor by half-capping a thin layer of silicon dioxide (4 nm SiO2) onto a mesoporous silica nanoparticle (MSNP) of 90 nm, enabling asymmetry to the nano-architecture. The nano-motors are chemically powered by the decomposition of H2O2 triggered by the enzyme catalase located at one face of the nanoparticles. The self-propulsion is characterized by dynamic light scattering (DLS) and optical microscopy. The apparent diffusion coefficient was enhanced by 150% compared to their Brownian motion at low H2O2 concentration (i.e. below 3 wt%). Mesoporous nano-motors might serve as active drug delivery nano-systems in future biomedical applications such as intracellular drug delivery.

JTD Keywords: Enzyme catalysis, Janus particles, Mesoporous silica, Nano-motors, Nanomachine, Self-propulsion

Lysosomal storage disorders are currently treated by enzyme replacement therapy (ERT) through the direct administration of the unprotected recombinant protein to the patients. Herein we present an ionically cross-linked polyelectrolyte complex (PEC) composed of trimethyl chitosan (TMC) and α-galactosidase A (GLA), the defective enzyme in Fabry disease, with the capability of directly targeting endothelial cells by incorporating peptide ligands containing the RGD sequence. We assessed the physicochemical properties, cytotoxicity, and hemocompatibility of RGD-targeted and untargeted PECs, the uptake by endothelial cells and the intracellular activity of PECs in cell culture models of Fabry disease. Moreover, we also explored the effect of different freeze-drying procedures in the overall activity of the PECs. Our results indicate that the use of integrin-binding RGD moiety within the PEC increases their uptake and the efficacy of the GLA enzyme, while the freeze-drying allows the activity of the therapeutic protein to remain intact. Overall, these results highlight the potential of TMC-based PECs as a highly versatile and feasible drug delivery system for improving the ERT of lysosomal storage disorders.

JTD Keywords: Enzyme replacement therapy, Fabry disease, Lysosomal delivery, Nanomedicine, Polyelectrolyte complexes, Trimethyl chitosan, α-galactosidase A

The development of synthetic nanomotors for technological applications in particular for life science and nanomedicine is a key focus of current basic research. However, it has been challenging to make active nanosystems based on biocompatible materials consuming nontoxic fuels for providing self-propulsion. Here, we fabricate self-propelled Janus nanomotors based on hollow mesoporous silica nanoparticles (HMSNPs), which are powered by biocatalytic reactions of three different enzymes: catalase, urease, and glucose oxidase (GOx). The active motion is characterized by a mean-square displacement (MSD) analysis of optical video recordings and confirmed by dynamic light scattering (DLS) measurements. We found that the apparent diffusion coefficient was enhanced by up to 83%. In addition, using optical tweezers, we directly measured a holding force of 64 ± 16 fN, which was necessary to counteract the effective self-propulsion force generated by a single nanomotor. The successful demonstration of biocompatible enzyme-powered active nanomotors using biologically benign fuels has a great potential for future biomedical applications.

JTD Keywords: Enzyme, Hollow mesoporous silica nanoparticles, Hybrid motors, Janus particles, Nanomotors, Optical tweezers

Lung decellularization is based on the use of physical, chemical, or enzymatic methods to break down the integrity of the cells followed by a treatment to extract the cellular material from the lung scaffold. The aim of this study was to characterize the mechanical changes throughout the different steps of lung decellularization process. Four lungs from mice (C57BL/6) were decellularized by using a conventional protocol based on sodium dodecyl sulfate. Lungs resistance (RL) and elastance (EL) were measured along decellularization steps and were computed by linear regression fitting of tracheal pressure, flow, and volume during mechanical ventilation. Transients differences found were more distinct in an intermediate step after the lungs were rinsed with deionized water and treated with 1% SDS, whereupon the percentage of variation reached approximately 80% for resistance values and 30% for elastance values. In conclusion, although a variation in extracellular matrix stiffness was observed during the decellularization process, this variation can be considered negligible overall because the resistance and elastance returned to basal values at the final decellularization step.

JTD Keywords: Lung bioengineering, Lung decellularization, Organ scaffold, dodecyl sulfate sodium, animal tissue, article, artificial ventilation, compliance (physical), controlled study, enzyme chemistry, extracellular matrix, female, flow, lung, lung decellularization, lung pressure, lung resistance, mouse, nonhuman, positive end expiratory pressure, priority journal, rigidity, tissue engineering, trachea pressure

We present a method to measure directly and at the single-molecule level the distance decay constant that characterizes the rate of electron transfer (ET) in redox proteins. Using an electrochemical tunneling microscope under bipotentiostatic control, we obtained current-distance spectroscopic recordings of individual redox proteins confined within a nanometric tunneling gap at a well-defined molecular orientation. The tunneling current decays exponentially, and the corresponding decay constant (β) strongly supports a two-step tunneling ET mechanism. Statistical analysis of decay constant measurements reveals differences between the reduced and oxidized states that may be relevant to the control of ET rates in enzymes and biological electron transport chains.

JTD Keywords: Long-range electron transfer (LRET), Distance decay constant, Single-molecule electrochemistry, Redox enzyme, Metalloprotein, Blue copper protein, Azurin, Electrochemical scanning tunneling microscopy and spectroscopy, Nanoelectrodes, Debye length, Electrochemical charge screening

Ochratoxin A (OTA) is one of the most important mycotoxins because of its high toxicity to both humans and animals and its occurrence in a number of basic foods and agro-products. The need to develop high-performing methods for OTA analysis able to improve the traditional ones is evident. In this work, through in vitro SELEX (Systematic Evolution of Ligands by EXponential enrichment) two aptamers, designated H8 and H12 were produced that bind with nanomolar affinity with Ochratoxin A (OTA). Two strategies were investigated by using an indirect and a direct competitive Enzyme-Linked Aptamer Assay (ELAA) and were compared to the classical competitive Enzyme-Linked Immunosorbent Assay (ELISA) for the determination of OTA in spiked red wine samples. The limit of detection attained (1 ng/mL), the midpoint value obtained (5 ng/mL) and the analysis time needed (125 min) for the real sample analysis validate the direct competitive ELAA as useful screening tool for routine use in the control of OTA level in wine.

JTD Keywords: Competitive Enzyme-Linked Aptamer Assay (ELAA), DNA aptamer, Ochratoxin A, SELEX, Wine analysis

Bacillus anthracis is a severe mammalian pathogen. The deoxyribonucleotides necessary for DNA replication and repair are provided via the ribonucleotide reductase (RNR) enzyme. RNR is also important for spore germination and cell proliferation upon infection. We show that the expression of B. anthracis class Ib RNR responds to the environment that the pathogen encounters upon infection. We also show that several anti-proliferative agents (radical scavengers) specifically inhibit the B. anthracis RNR. Owing to the importance of RNR in the pathogenic infection process, our results highlight a promising potential to inhibit the growth of B. anthracis early during infection.

JTD Keywords: Anthrax, Antibacterial drug, Antibacterial target, Enzyme inhibition

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JTD Keywords: Self-assembled monolayers, High-aspect-ratio, Dip-pen nanolithography, Langmuir-blodgett-films, Conducting polymer, Enzymes, Microstructures, Immunosensors, Fabrication, Stability