Cationic Starch Nanoparticles for Enhancing CpG Oligodeoxynucleotide-Mediated Antitumor Immunity.

CpG ODNs demonstrate a significant promise for immunotherapy. However, their application is limited owing to quick DNase digestion and inadequate cellular internalization. Transportation of CpG ODNs into immune cells is crucial. Although viral vectors exhibit high transfection efficiency, safety risks, high cost, and low carrying capacity remain big obstacles. Herein, a novel CpG ODNs vector was fabricated by using starch. Starch was ultrasonicated and simply aminated (NH2-St) through grafting with diethylenetriamine, which was spherical with a diameter of 50 nm. NH2-St possessed good biocompatibility. Cationic NH2-St encapsulated CpG ODNs well and possessed a high loading capacity of 317 µg/mg. NH2-St protected CpG ODNs from nuclease digestion and significantly enhanced their cellular uptake. NH2-St/CpG induced the potent secretion of antitumor cytokines from macrophages and effectively suppressed the growth of tumor cells. This work highlights the promise of starch for CpG ODNs delivery, which brings new hope for cancer immunotherapy.

Visualizing Cathepsin K-Cre Expression at the Single-Cell Level with GFP Reporters.

The Cre/lox system is a fundamental tool for functional genomic studies, and a number of Cre lines have been generated to target genes of interest spatially and temporally in defined cells or tissues; this approach has greatly expanded our knowledge of gene functions. However, the limitations of this system have recently been recognized, and we must address the challenge of so-called nonspecific/off-target effects when a Cre line is utilized to investigate a gene of interest. For example, cathepsin K (Ctsk) has been used as a specific osteoclast marker, and Cre driven by its promoter is widely utilized for osteoclast investigations. However, Ctsk-Cre expression has recently been identified in other cell types, such as osteocytes, periosteal stem cells, and tenocytes. To better understand Ctsk-Cre expression and ensure appropriate use of this Cre line, we performed a comprehensive analysis of Ctsk-Cre expression at the single-cell level in major organs and tissues using two green fluorescent protein (GFP) reporters (ROSA nT-nG and ROSA tdT) and a tissue clearing technique in young and aging mice. The expression profile was further verified by immunofluorescence staining and droplet digital RT-PCR. The results demonstrate that Ctsk-Cre is expressed not only in osteoclasts but also at various levels in osteoblast lineage cells and other major organs/tissues, particularly in the brain, kidney, pancreas, and blood vessels. Furthermore, Ctsk-Cre expression increases markedly in the bone marrow, skeletal muscle, and intervertebral discs in aging mice. These data will be valuable for accurately interpreting data obtained from in vivo studies using Ctsk-Cre mice to avoid potentially misleading conclusions. © 2022 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Immune niches orchestrated by intestinal mesenchymal stromal cells lining the crypt-villus.

The mammalian intestine is an organ that can be spatially defined by two axes: longitudinal and vertical. Such anatomical structure ensures the maintenance of a relatively immuno-quiescent and proliferation-promoting crypt for intestinal stem cell differentiation while actively warding off the invading intestinal microbes at the villus tip during digestion and nutrient absorption. Such behavior is achieved by the fine coordination among intestinal epithelial cells, intestinal mesenchymal stromal cells and tissue-resident immune cells like myeloid cells and lymphocytes. Among these cell types resided in the colon, intestinal mesenchymal stromal cells are considered to be the essential link between epithelium, vasculature, neuronal system, and hematopoietic compartment. Recent advancement of single cell and spatial transcriptomics has enabled us to characterize the spatial and functional heterogeneity of intestinal mesenchymal stromal cells. These studies reveal distinctive intestinal mesenchymal stromal cells localized in different regions of the intestine with diverse functions including but not limited to providing cytokines and growth factors essential for different immune cells and epithelial cells which predict niche formation for immune function from the villus tip to the crypt bottom. In this review, we aim to provide an overall view of the heterogeneity of intestinal mesenchymal stromal cells, the spatial distribution of these cells along with their interaction with immune cells and the potential regulatory cytokine profile of these cell types. Summarization of such information may enrich our current understanding of the immuno-regulatory functions of the newly identified mesenchymal stromal cell subsets beyond their epithelial regulatory function.

Preparation of coated paper reinforced by a blend of anionic-starch-based nanocellulose/chitosan and its properties.

Carboxylated cellulose nanocrystal whisker (C-CNC) and chitosan (CTS) were used to blend and reinforce anionic starch (AS) to prepare a paper-coating agent, AS-CNC-CTS, which was coated on one side of the surface of offset paper and kraft paper. Scanning electron microscopy (SEM) showed that the AS-CNC-CTS coating agent can form a layer of dense film on the paper surface and fill the surface pores. And also, owing to the irregular pore structure of the paper, the coating agent penetrated the pores to different degrees. The structure and mechanical properties of the coated paper were analyzed using a Fourier infrared spectrometer, computer-controlled paper-tearing tester and paper tensile strength test machine. Peptide bonding interaction between C-CNC and CTS, hydrogen bonding between C-CNC and CTS, C-CNC and AS, C-CNC and paper fibers, as well as electrostatic attraction between acidified CTS and AS were found. Moreover, the coating agent also had good antibacterial properties, and no mold spots formed throughout the observation period (60d). The gas-barrier properties and oil resistance of the coated paper were further studied using a paper and paperboard air permeability tester and a paper oil-permeability tester. Results showed that the coating agent can significantly enhance the gas-barrier properties and oil resistance of paper. Furthermore, with increased C-CNC content in the coating agent, its barrier properties gradually increased. This finding indicated that the coating preparation had no effect on the crystal region of C-CNC.

The Current Research of Combining Multi-Modal Brain-Computer Interfaces With Virtual Reality.

Combing brain-computer interfaces (BCI) and virtual reality (VR) is a novel technique in the field of medical rehabilitation and game entertainment. However, the limitations of BCI such as a limited number of action commands and low accuracy hinder the widespread use of BCI-VR. Recent studies have used hybrid BCIs that combine multiple BCI paradigms and/or the multi-modal biosensors to alleviate these issues, which may become the mainstream of BCIs in the future. The main purpose of this review is to discuss the current status of multi-modal BCI-VR. This study first reviewed the development of the BCI-VR, and explored the advantages and disadvantages of incorporating eye tracking, motor capture, and myoelectric sensing into the BCI-VR system. Then, this study discussed the development trend of the multi-modal BCI-VR, hoping to provide a pathway for further research in this field.

Lovastatin inhibits Toll-like receptor 4 signaling in microglia by targeting its co-receptor myeloid differentiation protein 2 and attenuates neuropathic pain.

There is growing interest in drug repositioning to find new therapeutic indications for drugs already approved for use in people. Lovastatin is an FDA approved drug that has been used clinically for over a decade as a lipid-lowering medication. While lovastatin is classically considered to act as a hydroxymethylglutaryl (HMG)-CoA reductase inhibitor, the present series of studies reveal a novel lovastatin effect, that being as a Toll-like receptor 4 (TLR4) antagonist. Lovastatin selectively inhibits lipopolysaccharide (LPS)-induced TLR4-NF-κB activation without affecting signaling by other homologous TLRs. In vitro biophysical binding and cellular thermal shift assay (CETSA) show that lovastatin is recognized by TLR4's coreceptor myeloid differentiation protein 2 (MD-2). This finding is supported by molecular dynamics simulations that lovastatin targets the LPS binding pocket of MD-2 and lovastatin binding stabilizes the MD-2 conformation. In vitro studies of BV-2 microglial cells revealed that lovastatin inhibits multiple effects of LPS, including activation of NFkB; mRNA expression of tumor necrosis factor-a, interleukin-6 and cyclo-oxygenase 2; production of nitric oxide and reactive oxygen species; as well as phagocytic activity. Furthermore, intrathecal delivery of lovastatin over lumbosacral spinal cord of rats attenuated both neuropathic pain from sciatic nerve injury and expression of the microglial activation marker CD11 in lumbar spinal cord dorsal horn. Given the well-established role of microglia and proinflammatory signaling in neuropathic pain, these data are supportive that lovastatin, as a TLR4 antagonist, may be productively repurposed for treating chronic pain.

Dissecting the Innate Immune Recognition of Opioid Inactive Isomer (+)-Naltrexone Derived Toll-like Receptor 4 (TLR4) Antagonists.

The opioid inactive isomer (+)-naltrexone is one of the rare Toll-like receptor 4 (TLR4) antagonists with good blood-brain barrier (BBB) permeability, which is a lead with promising potential for treating neuropathic pain and drug addiction. (+)-Naltrexone targets the lipopolysaccharides (LPS) binding pocket of myeloid differentiation protein 2 (MD-2) and blocks innate immune TLR4 signaling. However, the details of the molecular interactions of (+)-naltrexone and its derivatives with MD-2 are not fully understood, which hinders the ligand-based drug discovery. Herein, in silico and in vitro assays were performed to elucidate the innate immune recognition of the opioid inactive (+)-isomers. The results showed that the conserved LPS binding pocket of MD-2 accommodated these opioid inactive (+)-isomers. The calculated binding free energies of (+)-naltrexone and its derivatives in complex with MD-2 correlated well with their experimental binding affinities and TLR4 antagonistic activities. Hydrophobic residues in the MD-2 cavity interacted directly with these (+)-naltrexone based TLR4 antagonists and principally participated in ligand binding. Increasing the hydrophobicity of substituted group at N-17 improved its TLR4 antagonistic activity, while charged groups disfavored the binding with MD-2. Molecular dynamics (MD) simulations showed the binding of (+)-naltrexone or its derivatives to MD-2 stabilized the "collapsed" conformation of MD-2, consequently blocking the binding and signaling of TLR4. Thermodynamics and dynamic analysis showed the topology of substituted group at N-17 of (+)-naltrexone affected the binding with MD-2 and TLR4 antagonistic activity. This study provides a molecular insight into the innate immune recognition of opioid inactive (+)-isomers, which would be of great help for the development of next-generation of (+)-opioid based TLR4 antagonists.

Evaluation of a laying-hen tracking algorithm based on a hybrid support vector machine.

BACKGROUND: Behavior is an important indicator reflecting the welfare of animals. Manual analysis of video is the most commonly used method to study animal behavior. However, this approach is tedious and depends on a subjective judgment of the analysts. There is an urgent need for automatic identification of individual animals and automatic tracking is a fundamental part of the solution to this problem. RESULTS: In this study, an algorithm based on a Hybrid Support Vector Machine (HSVM) was developed for the automated tracking of individual laying hens in a layer group. More than 500 h of video was conducted with laying hens raised under a floor system by using an experimental platform. The experimental results demonstrated that the HSVM tracker outperformed the Frag (fragment-based tracking method), the TLD (Tracking-Learning-Detection), the PLS (object tracking via partial least squares analysis), the MeanShift Algorithm, and the Particle Filter Algorithm based on their overlap rate and the average overlap rate. CONCLUSIONS: The experimental results indicate that the HSVM tracker achieved better robustness and state-of-the-art performance in its ability to track individual laying hens than the other algorithms tested. It has potential for use in monitoring animal behavior under practical rearing conditions.