Mesenchymal stem cells (MSCs) have been widely studied as a versatile cell source for tissue regeneration and remodeling due to their potent bioactivity, which includes modulation of inflammation ...response, macrophage polarization toward proregenerative lineage, promotion of angiogenesis, and reduction in fibrosis. This review focuses on profiling the effects of paracrine signals of MSCs, commonly referred to as the secretome, and highlighting the various engineering approaches to tune the MSC secretome. Recent advances in biomaterials-based therapeutic strategies for delivery of MSCs and MSC-derived secretome in the form of extracellular vesicles are discussed, along with their advantages and challenges.
T cell therapies require the removal and culture of T cells ex vivo to expand several thousand‐fold. However, these cells often lose the phenotype and cytotoxic functionality for mediating effective ...therapeutic responses. The extracellular matrix (ECM) has been used to preserve and augment cell phenotype; however, it has not been applied to cellular immunotherapies. Here, a hyaluronic acid (HA)‐based hydrogel is engineered to present the two stimulatory signals required for T‐cell activation—termed an artificial T‐cell stimulating matrix (aTM). It is found that biophysical properties of the aTM—stimulatory ligand density, stiffness, and ECM proteins—potentiate T cell signaling and skew phenotype of both murine and human T cells. Importantly, the combination of the ECM environment and mechanically sensitive TCR signaling from the aTM results in a rapid and robust expansion of rare, antigen‐specific CD8+ T cells. Adoptive transfer of these tumor‐specific cells significantly suppresses tumor growth and improves animal survival compared with T cells stimulated by traditional methods. Beyond immediate immunotherapeutic applications, demonstrating the environment influences the cellular therapeutic product delineates the importance of the ECM and provides a case study of how to engineer ECM‐mimetic materials for therapeutic immune stimulation in the future.
Significant improvements to cellular immunotherapy for cancer is achieved through engineering a novel T‐cell stimulating biomaterial hydrogel. Particularly interesting, the stiffness of the hydrogel drastically impacts mechanically sensitive T cell stimulation. Similarly, the hydrogel material, hyaluronic acid, contributes additional beneficial signaling to maintain a functional phenotype of stimulated T cells, demonstrating the importance of the environment on immune cell therapies.
Cell‐free deoxyribonucleic acid (cfDNA) released from either dead or damaged cells serves as a key autoantigen in rheumatoid arthritis (RA). They can be recognized by nucleic acid (NA) sensors such ...as the toll‐like receptor (TLR), leading to activation of the innate immune system and chronic inflammation. Developed here is a cationic molecular scavenger, by screening cationic dendronized polymers, which eliminates cfDNA and inhibits TLR recognition and nucleic‐acid‐induced inflammation. The structure–property study demonstrates that toxicity, NA binding capacity, and biodistribution could be balanced to achieve maximum therapeutic effect by exquisite control of the molecular structure. In addition, the optimized cationic polymer effectively inhibited joint swelling, synovial hyperplasia, and bone destruction in collagen‐induced arthritis (CIA) rat models. The results offer support for synthetic polymers offering new paradigm in autoimmune disease treatment.
Scavenger hunt: Screening of cationic dendronized polymers led to scavengers that could eliminate cell‐free DNAs and inhibit Toll‐like receptor recognition and nucleic‐acid‐induced inflammation. The scavengers having longer backbones and higher charge densities were preferentially accumulated in the inflammatory joints of arthritis rats. As a result, joint swelling, synovial hyperplasia, and bone destruction were inhibited.
Abstract
Lipid nanoparticles (LNPs) are effective vehicles to deliver mRNA vaccines and therapeutics. It has been challenging to assess mRNA packaging characteristics in LNPs, including payload ...distribution and capacity, which are critical to understanding structure-property-function relationships for further carrier development. Here, we report a method based on the multi-laser cylindrical illumination confocal spectroscopy (CICS) technique to examine mRNA and lipid contents in LNP formulations at the single-nanoparticle level. By differentiating unencapsulated mRNAs, empty LNPs and mRNA-loaded LNPs via coincidence analysis of fluorescent tags on different LNP components, and quantitatively resolving single-mRNA fluorescence, we reveal that a commonly referenced benchmark formulation using DLin-MC3 as the ionizable lipid contains mostly 2 mRNAs per loaded LNP with a presence of 40%–80% empty LNPs depending on the assembly conditions. Systematic analysis of different formulations with control variables reveals a kinetically controlled assembly mechanism that governs the payload distribution and capacity in LNPs. These results form the foundation for a holistic understanding of the molecular assembly of mRNA LNPs.
Background and Aims
Hepatocellular carcinoma (HCC) represents the third leading cause of cancer‐related mortality in the world. Over the past two decades, there has been minimal improvement in ...therapies as well as clinical outcomes for patients with Barcelona Clinic Liver Cancer (BCLC)‐B. These patients are treated with local interventions, including transarterial chemoembolization. Current methodologies only allow sustained intratumoral release measured in hours. Methodologies to allow sustained local release of the drug cargo over days to weeks are acutely needed. We hypothesize that tumor response as well as outcomes of patients with BCLC‐B can be improved through utilization of a highly cytotoxic agent delivered with a sustained release platform.
Approach and Results
High‐throughput drug screening across 40 HCC patient‐derived organoids identified bortezomib (BTZ) as a highly cytotoxic small molecule for HCC. We designed and manufactured sustained release BTZ nanoparticles (BTZ‐NP) using a flash nanocomplexation/nanoprecipitation process. We quantified the release profile and tested the anti‐tumoral effects in vivo. The BTZ‐NP formulation demonstrated a sustained release of BTZ of 30 days. This BTZ‐NP formulation was highly effective in controlling tumor size and improved survival in vivo in three animal models of HCC, including when delivered via the hepatic artery, as we envision its delivery in patients. In addition, the BTZ‐NP formulation was superior to treatment with doxorubicin‐drug eluting beads.
Conclusions
The BTZ‐NP formulation provides a potent and safe treatment of HCC via a localized delivery approach. These results warrant additional preclinical studies to advance this technology to human clinical trials.
Human HCC tissue was collected and patient derived organoids (PDO) were established. These PDOs were utilized for high throughput drug screening, which led to identifying bortezomib as a highly potent anti‐HCC drug. Bortezomib was then formulated with PLGA nanoparticles for sustained release (BTZ‐NP). Efficacy of BTZ‐NP was tested in 3 animal models. First, it was tested in a patient derived xenograft model (PDX) through direct intra‐tumoral injection. Next, BTZ‐NP was tested in an immunocompetent mouse model (Hepa 1‐6 cells injected into the liver of C57bl/6j mice) through a direct intra‐tumoral injection approach. Last, to simulate trans‐arterial delivery through the hepatic artery, a rat model of HCC was developed and utilized to test BTZ‐NP.
Organelles play crucial roles in cellular activities and the functions of organelles are related greatly to the pH values, therefore, the bio-imaging of targeted organelles and their related pH ...sensing is of great importance in biological assays. Herein we report the fluorescence imaging of specific organelles, i.e., lysosomes and endoplasmic reticulum, and their pH sensing with surface regulated carbon dots (CDs). Carbon dots functionalized with amine groups (ACDs) are first prepared by hydrothermal treatment of citric acid and urea, and then laurylamine functionalized CDs (LCDs) are obtained via the conjugation of laurylamine with ACDs. The as-prepared ACDs and LCDs provide clear and bright imaging results for the lysosome and endoplasmic reticulum, respectively. The subcellular targeting features of the two CDs are attributed to their surface chemistries and cellular uptake pathways. Moreover, both the CDs are pH responsive within a certain pH range, i.e., 4.0-5.4 for ACDs and 6.2-7.2 for LCDs. The ACDs and LCDs are thus successfully applied to visualize the pH fluctuations of the lysosome and endoplasmic reticulum in MCF-7 cells.
Optical chirality sensing has attracted a lot of interest due to its potential in high‐throughput screening in chirality analysis. A molecular sensor is required to convert the chirality of analytes ...into optical signals. Although many molecular sensors have been reported, sensors with wide substrate scope remain to be developed. Herein, we report that the amide naphthotube‐based chirality sensors have an unprecedented wide scope for chiroptical sensing of organic molecules. The substrates include, but are not limited to common organic products in asymmetric catalysis, chiral molecules with inert groups or remote functional groups from their chiral centers, natural products and their derivatives, and chiral drugs. The effective chirality sensing is based on biomimetic recognition in water and on effective chirality transfer through guest‐induced formation of a chiral conformation of the sensors. Furthermore, the sensors can be used in real‐time monitoring on reaction kinetics in water and in determining absolute configurations and ee values of the products in asymmetric catalysis.
Optical chirality sensing of a wide scope of organic molecules, including common products in asymmetric catalysis, natural products, and chiral drugs, has been achieved using amide naphthotubes in water. The use of water as solvent and the possibility to readily recover the sensors makes this method environmentally friendly.
Abstract
Induced fit and conformational selection are two dominant binding mechanisms in biology. Although induced fit has been widely accepted by supramolecular chemists, conformational selection is ...rarely studied with synthetic systems. In the present research, we report a macrocyclic host whose binding mechanism is unambiguously assigned to conformational selection. The kinetic and thermodynamic aspects of this system are studied in great detail. It reveals that the kinetic equation commonly used for conformational selection is strictly followed here. In addition, two mathematical models are developed to determine the association constants of the same guest to the two host conformations. A “conformational selectivity factor” is defined to quantify the fidelity of conformational selection. Many details about the kinetic and thermodynamic aspects of conformational selection are revealed by this synthetic system. The conclusion and the mathematical models reported here should be helpful in understanding complex molecular recognition in both biological and synthetic systems.
A central neural circuit for itch sensation Mu, Di; Deng, Juan; Liu, Ke-Fei ...
Science (American Association for the Advancement of Science),
08/2017, Letnik:
357, Številka:
6352
Journal Article
Recenzirano
Although itch sensation is an important protective mechanism for animals, chronic itch remains a challenging clinical problem. Itch processing has been studied extensively at the spinal level. ...However, how itch information is transmitted to the brain and what central circuits underlie the itch-induced scratching behavior remain largely unknown. We found that the spinoparabrachial pathway was activated during itch processing and that optogenetic suppression of this pathway impaired itch-induced scratching behaviors. Itch-mediating spinal neurons, which express the gastrin-releasing peptide receptor, are disynaptically connected to the parabrachial nucleus via glutamatergic spinal projection neurons. Blockade of synaptic output of glutamatergic neurons in the parabrachial nucleus suppressed pruritogen-induced scratching behavior. Thus, our studies reveal a central neural circuit that is critical for itch signal processing.
In the present study, octa-aminopropyl polyhedral oligomeric silsesquioxane hydrochloride salt (OA-POSS) functionalized carbon dots (CDs/POSS) are prepared by a one-pot approach with glycerol as ...carbon source and solvent medium. OA-POSS serves as a passivation agent, and it is obtained via hydrolytic condensation of 3-aminopropyltriethoxysilane (APTES). During the functionalization process, the amino groups on OA-POSS combine with carboxylic groups on the bare CDs via formation of amide bond to construct organic–inorganic hybrid carbon dots. The obtained CDs/POSS are well dispersed in aqueous medium with a diameter of ca. 3.6 nm. It is demonstrated that CDs/POSS provide favorable photoluminescent property with a quantum yield of 24.0%. They also exhibit resistance to photobleaching and excellent photoluminescence stability in the presence of biological sample matrix (characterized by heavy metals and organic molecules), which facilitate cell imaging in biological systems. Both the photoluminescent emission wavelength and the fluorescence intensity depend closely on the excitation wavelength, and thus, it provides a potential for multicolor imaging as demonstrated with HeLa cells and MCF-7 cells.
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