bims-drudre Biomed News
on Targeted drug delivery and programmed release mechanisms
Issue of 2022‒04‒24
fifteen papers selected by
Ceren Kimna
Technical University of Munich

  1. J Control Release. 2022 Apr 19. pii: S0168-3659(22)00218-8. [Epub ahead of print]
      Multidrug resistance (MDR) to chemotherapeutic drugs and targeted drug delivery are recurring issues in clinical cancer treatment. Here, a multifunctional fusion protein-DNA conjugate was designed as a co-delivery vehicle for anticancer peptides and chemotherapeutic drugs to combat both drug-resistant and drug-sensitive tumor cells. The fusion protein was constructed by fusing a PsTag polypeptide, a matrix metalloproteinase 2 (MMP2)-degradable domain, and the mitochondria-targeted pro-apoptotic peptide KLAKLAKKLAKLAK. Doxorubicin was efficiently loaded into the fusion protein pre-conjugated dendrimer-like DNA nanostructure. With the incorporation of enhanced stability, tumor targeting, and controlled-release elements, the tailored nanostructure can selectively enter tumor cells and synergistically exert antitumor activity with no significant adverse effects. Thus, these protein-conjugated DNA nanocarriers could be a potential co-delivery system for protein/peptide and chemotherapeutic drugs delivery in synergistic cancer therapy.
    Keywords:  Cancer; DNA nanotechnology; Drug delivery; Multidrug resistance; Peptide therapeutics
  2. Sci Adv. 2022 Apr 22. 8(16): eabm8011
      We designed a unique nanocapsule for efficient single CRISPR-Cas9 capsuling, noninvasive brain delivery and tumor cell targeting, demonstrating an effective and safe strategy for glioblastoma gene therapy. Our CRISPR-Cas9 nanocapsules can be simply fabricated by encapsulating the single Cas9/sgRNA complex within a glutathione-sensitive polymer shell incorporating a dual-action ligand that facilitates BBB penetration, tumor cell targeting, and Cas9/sgRNA selective release. Our encapsulating nanocapsules evidenced promising glioblastoma tissue targeting that led to high PLK1 gene editing efficiency in a brain tumor (up to 38.1%) with negligible (less than 0.5%) off-target gene editing in high-risk tissues. Treatment with nanocapsules extended median survival time (68 days versus 24 days in nonfunctional sgRNA-treated mice). Our new CRISPR-Cas9 delivery system thus addresses various delivery challenges to demonstrate safe and tumor-specific delivery of gene editing Cas9 ribonucleoprotein for improved glioblastoma treatment that may potentially be therapeutically useful in other brain diseases.
  3. Nat Commun. 2022 Apr 19. 13(1): 2038
      Developing precise nanomedicines to improve the transport of anticancer drugs into tumor tissue and to the final action site remains a critical challenge. Here, we present a bioorthogonal in situ assembly strategy for prolonged retention of nanomedicines within tumor areas to act as drug depots. After extravasating into the tumor site, the slightly acidic microenvironment induces the exposure of cysteine on the nanoparticle surface, which subsequently undergoes a bioorthogonal reaction with the 2-cyanobenzothiazole group of another neighboring nanoparticle, enabling the formation of micro-sized drug depots to enhance drug retention and enrichment. This in situ nanoparticle assembly strategy remarkably improves the antimetastatic efficacy of extracellular-targeted drug batimastat, and also leads to the simultaneous enhanced retention and sustained release of multiple agents for combined cocktail chemoimmunotherapy to finally elicit a potent antitumor immune response. Such in situ assembly of nanomedicines represents a generalizable strategy towards extracellular drug delivery and cocktail chemoimmunotherapy.
  4. J Am Chem Soc. 2022 Apr 19.
      Artificial antigen-presenting cells (aAPCs) constructed by integrating T cell activation ligands on biocompatible materials hold great potential in tumor immunotherapy. However, it remains challenging to develop aAPCs, which could mimic the characteristics of natural APCs, thereby realizing antigen-specific T cells activation in vivo. Here, we report the first effort to construct natural lymphocyte-based homologous targeting aAPCs (LC-aAPCs) with lipid-DNA-mediated noninvasive live cell surface engineering. Through a predesigned bottom-up self-assembly path, we achieved natural-APC-mimicking distribution of T cell activation ligands on LC-aAPCs, which would enable the optimized T cell activation. Moreover, the lipid-DNA-mediated self-assembly occurring on lipid bilayers would not affect the functions of homing receptors expressed on lymphocyte. Therefore, such LC-aAPCs could actively migrate to peripheral lymphatic organs and then effectively activate antigen-specific T cells. Combined with an immune checkpoint inhibitor, such LC-aAPCs could effectively inhibit the growth of different tumor models. Thus, our work provides a new design of aAPCs for in vivo applications in tumor immunotherapy, and the lipid-DNA-mediated noninvasive live cell surface engineering would be a powerful tool for designing cell-based therapeutics.
  5. ACS Nano. 2022 Apr 18.
      Current strategies for the delivery of proteins into cells face general challenges of endosomal entrapment and concomitant degradation of protein cargo. Efficient delivery directly to the cytosol overcomes this obstacle: we report here the use of biotin-streptavidin tethering to provide a modular approach to the generation of nanovectors capable of a cytosolic delivery of biotinylated proteins. This strategy uses streptavidin to organize biotinylated protein and biotinylated oligo(glutamate) peptide into modular complexes that are then electrostatically self-assembled with a cationic guanidinium-functionalized polymer. The resulting polymer-protein nanocomposites demonstrate efficient cytosolic delivery of six biotinylated protein cargos of varying size, charge, and quaternary structure. Retention of protein function was established through efficient cell killing via delivery of the chemotherapeutic enzyme granzyme A. This platform represents a versatile and modular approach to intracellular delivery through the noncovalent tethering of multiple components into a single delivery vector.
    Keywords:  biotin−streptavidin; cytosolic delivery; polymer nanocarrier; protein delivery; supramolecular
  6. Nat Commun. 2022 Apr 19. 13(1): 2117
      The gut microbiota represents a large community of microorganisms that play an important role in immune regulation and maintenance of homeostasis. Living bacteria receive increasing interest as potential therapeutics for gut disorders, because they inhibit the colonization of pathogens and positively regulate the composition of bacteria in gut. However, these treatments are often accompanied by antibiotic administration targeting pathogens. In these cases, the efficacy of therapeutic bacteria is compromised by their susceptibility to antibiotics. Here, we demonstrate that a single-cell coating composed of tannic acids and ferric ions, referred to as 'nanoarmor', can protect bacteria from the action of antibiotics. The nanoarmor protects both Gram-positive and Gram-negative bacteria against six clinically relevant antibiotics. The multiple interactions between the nanoarmor and antibiotic molecules allow the antibiotics to be effectively absorbed onto the nanoarmor. Armored probiotics have shown the ability to colonize inside the gastrointestinal tracts of levofloxacin-treated rats, which significantly reduced antibiotic-associated diarrhea (AAD) resulting from the levofloxacin-treatment and improved some of the pre-inflammatory symptoms caused by AAD. This nanoarmor strategy represents a robust platform to enhance the potency of therapeutic bacteria in the gastrointestinal tracts of patients receiving antibiotics and to avoid the negative effects of antibiotics in the gastrointestinal tract.
  7. Adv Mater. 2022 Apr 22. e2201042
      A unique robotic medical platform is designed by utilizing cell robots as the active "trojan horse" of oncolytic adenovirus (OA), capable of tumor-selective binding and killing. The OA-loaded cell robots are fabricated by entirely modifying OA-infected 293T cells with cyclic-RGD peptide (cRGD) to specific bind with bladder cancer cells, followed with asymmetric immobilization of Fe3 O4 nanoparticles (NPs) on the cell surface. OA can replicate in host cells and induce cytolysis to release virus progeny to surrounding tumor site for sustainable infection and oncolysis. The asymmetric coating of magnetic NPs bestows cell robots with effective movement in various media and wireless manipulation with directional migration in a microfluidic device and bladder mold under magnetic control, further enabling steerable movement and prolonged retention of cell robots in mouse bladder. The biorecognition of cRGD and robust, controllable propulsion of cell robots work synergistically to greatly enhance their tissue penetration and anticancer efficacy in the three-dimensional (3D) cancer spheroid and orthotopic mouse bladder tumor model. Overall, this study integrates cell-based microrobots with virotherapy to generate an attractive robotic system with tumor specificity, expanding the operation scope of cell robots in biomedical community. This article is protected by copyright. All rights reserved.
    Keywords:  bladder cancer; cell-based microrobots; magnetic propulsion; oncolytic adenovirus; virotherapy
  8. Adv Mater. 2022 Apr 21. e2200217
      The ability to replicate the three-dimensional myocardial architecture found in human hearts is a grand challenge. Here, we report the fabrication of aligned cardiac tissues via bioprinting anisotropic organ building blocks (aOBBs) composed of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). We first generated a bioink composed of contractile cardiac aOBBs and printed aligned cardiac tissue sheets with linear, spiral, and chevron features. Next, we printed aligned cardiac macrofilaments, whose contractile force and conduction velocity increased over time and exceeded the performance of spheroid-based cardiac tissues. Finally, we highlighted the ability to spatially control the magnitude and direction of contractile force by printing cardiac sheets with different aOBB alignment. Our research opens new avenues to generating functional cardiac tissue with high cell density and complex cellularly alignment. This article is protected by copyright. All rights reserved.
    Keywords:  Aligned; anisotropic; bioprinting; cardiomyocytes; engineered cardiac tissue
  9. ACS Nano. 2022 Apr 19.
      Implantable bioelectrodes enable precise recording or stimulation of electrical signals with living tissues in close contact. However, their performance is frequently compromised owing to inflammatory tissue reactions, which macrophages either induce or resolve by polarizing to an inflammatory (M1) or noninflammatory (M2) phenotype, respectively. Thus, we aimed to fabricate biocompatible and functional implantable conductive polymer bioelectrodes with optimal topography for the modulation of macrophage responses. To this end, we produced heparin-doped polypyrrole (PPy/Hep) electrodes of different surface roughness, with Ra values from 5.5 to 17.6 nm, by varying the charge densities during electrochemical synthesis. In vitro culture revealed that macrophages on rough PPy/Hep electrodes preferentially polarized to noninflammatory phenotypes. In particular, PPy/Hep-900 (Ra = 14 nm) was optimal with respect to electrochemical properties and the suppression of inflammatory M1 polarization. In vivo implantation indicated that PPy/Hep-900 significantly reduced macrophage recruitment, suppressed inflammatory polarization, and mitigated fibrotic tissue formation. In addition, the implanted PPy/Hep-900 electrodes could successfully record electrocardiographic signals for up to 10 days without substantial decreases in sensitivity, while other electrodes substantially lost their signal sensitivity during implantation. Altogether, we demonstrate that modulating the surface features of PPy/Hep can benefit the design and applications of high-performance and high-biocompatibility bioelectrodes.
    Keywords:  biocompatibility; bioelectrode; implant; macrophage; polypyrrole
  10. ACS Appl Mater Interfaces. 2022 Apr 22.
      Melanins are natural biopolymers that have remarkable properties including UV-protection, coloration, and antioxidant activity. Their biosynthesis is regulated both spatially and temporally and involves supramolecular templating and compartmentalization of enzymes and reactants within specialized organelles called melanosomes. In contrast, the laboratory-based bulk synthesis of melanin by tyrosine or dopamine oxidation is a poorly controlled process, resulting in materials with undefined properties. Inspired by the pigment's biosynthesis, we developed a methodology to spatiotemporally regulate melanin formation in liquid droplets. The spatial control is achieved by sequestration of the reaction in dextran-rich droplets of a polyethylene glycol/dextran aqueous two-phase system, where the use of a photocleavable protected tyrosine provides a temporal control over its enzymatic oxidation-polymerization. We show that the liquid droplets allow for confined local reactivity as they serve as reaction centers for melanin synthesis and compartmentalize the melanin product. This methodology opens tremendous opportunities for applications in skincare and biomedicine.
    Keywords:  bioinspired materials; liquid droplets; melanin; phase separation; reaction compartmentalization; spatiotemporal control
  11. Nano Lett. 2022 Apr 20.
      Ever-growing various applications, especially for tissue regeneration, cause a pressing need for novel methods to functionalize melt electrowritten (MEW) microfibrous scaffolds with unique nanomaterials. Here, two novel strategies are proposed to modify MEW polycaprolactone (PCL) grids with ZnO nanoparticles (ZP) or ZnO nanoflakes (ZF) to enhance osteogenic differentiation. The calcium mineralization levels of MC3T3 osteoblasts cultured on PCL/ZP 0.1 scaffolds are ∼3.91-fold higher than those cultured on nonmodified PCL scaffolds, respectively. Due to the nanotopography mimicking bone anatomy, the PCL/ZF scaffolds (∼2.60 times higher in ALP activity compared to PCL/ZP 1 and ∼2.17 times higher in mineralization compared to PCL/ZP 0.1) achieved superior results. Moreover, the flexible feature inherited from PCL grids makes it possible for them to act as a reshapable osteogenic bioscaffold. This study provides new strategies for synthesizing nanomaterials on microscale surfaces, opening up a new route for functionalizing MEW scaffolds to fulfill the growing demand of tissue engineering.
    Keywords:  Melt electrowriting; ZnO nanomaterials; flexible osteogenic biomaterials; hydroxyapatite nanoparticles; osteogenic differentiation
  12. Adv Mater. 2022 Apr 18. e2201608
      Mechanical properties of biological systems provide useful information about the biochemical status of cells and tissues. Here we report an artificial tactile neuron enabling spiking representation of stiffness and spiking neural network (SNN)-based learning for disease diagnosis. An artificial spiking tactile neuron based on an ovonic threshold switch serving as an artificial soma and a piezoresistive sensor as an artificial mechanoreceptor is developed and shown to encode the elastic stiffness of pressed materials into spike frequency evolution patterns. SNN-based learning of ultrasound elastography images abstracted by spike frequency evolution rate enables the classification of malignancy status of breast tumors with a recognition accuracy up to 95.8%. The stiffness-encoding artificial tactile neuron and learning of spiking-represented stiffness patterns hold a great promise for the identification and classification of tumors for disease diagnosis and robot-assisted surgery with low power consumption, low latency, and yet high accuracy. This article is protected by copyright. All rights reserved.
    Keywords:  artificial tactile neuron; disease diagnosis; elastography; neuromorphic sensors; ovonic threshold switch; piezoresistive sensors; spiking neural networks
  13. Lab Chip. 2022 Apr 19.
      We present a new cell culture technology for large-scale mechanobiology studies capable of generating and applying optically controlled uniform compression on single cells in 3D. Mesenchymal stem cells (MSCs) are individually encapsulated inside an optically triggered nanoactuator-alginate hybrid biomaterial using microfluidics, and the encapsulating network isotropically compresses the cell upon activation by light. The favorable biomolecular properties of alginate allow cell culture in vitro up to a week. The mechanically active microgels are capable of generating up to 15% compressive strain and forces reaching 400 nN. As a proof of concept, we demonstrate the use of the mechanically active cell culture system in mechanobiology by subjecting singly encapsulated MSCs to optically generated isotropic compression and monitoring changes in intracellular calcium intensity.
  14. Nucleic Acids Res. 2022 Apr 21. pii: gkac255. [Epub ahead of print]
      It is important to control CRISPR/Cas9 when sufficient editing is obtained. In the current study, rational engineering of guide RNAs (gRNAs) is performed to develop small-molecule-responsive CRISPR/Cas9. For our purpose, the sequence of gRNAs are modified to introduce ligand binding sites based on the rational design of ligand-RNA pairs. Using short target sequences, we demonstrate that the engineered RNA provides an excellent scaffold for binding small molecule ligands. Although the 'stem-loop 1' variants of gRNA induced variable cleavage activity for different target sequences, all 'stem-loop 3' variants are well tolerated for CRISPR/Cas9. We further demonstrate that this specific ligand-RNA interaction can be utilized for functional control of CRISPR/Cas9 in vitro and in human cells. Moreover, chemogenetic control of gene editing in human cells transfected with all-in-one plasmids encoding Cas9 and designer gRNAs is demonstrated. The strategy may become a general approach for generating switchable RNA or DNA for controlling other biological processes.
  15. Nat Rev Gastroenterol Hepatol. 2022 Apr 19.
      Almost all currently available treatments for inflammatory bowel disease (IBD) act by inhibiting inflammation, often blocking specific inflammatory molecules. However, given the infectious and neoplastic disease burden associated with chronic immunosuppressive therapy, the goal of attaining mucosal healing without immunosuppression is attractive. The absence of treatments that directly promote mucosal healing and regeneration in IBD could be linked to the lack of understanding of the underlying pathways. The range of potential strategies to achieve mucosal healing is diverse. However, the targeting of regenerative mechanisms has not yet been achieved for IBD. Stem cells provide hope as a regenerative treatment and are used in limited clinical situations. Growth factors are available for the treatment of short bowel syndrome but have not yet been applied in IBD. The therapeutic application of organoid culture and stem cell therapy to generate new intestinal tissue could provide a novel mechanism to restore barrier function in IBD. Furthermore, blocking key effectors of barrier dysfunction (such as MLCK or damage-associated molecular pattern molecules) has shown promise in experimental IBD. Here, we review the diversity of molecular targets available to directly promote mucosal healing, experimental models to identify new potential pathways and some of the anticipated potential therapies for IBD.