Fc-engineered large molecules targeting blood-brain barrier transferrin receptor and CD98hc have distinct central nervous system and peripheral biodistribution.

Blood brain barrier-crossing molecules targeting transferrin receptor (TfR) and CD98 heavy chain (CD98hc) are widely reported to promote enhanced brain delivery of therapeutics. Here, we provide a comprehensive and unbiased biodistribution characterization of TfR and CD98hc antibody transport vehicles (ATV and ATV) compared to control IgG. Mouse whole-body tissue clearing reveals distinct organ localization for each molecule.

Novel high-content and open-source image analysis tools for profiling mitochondrial morphology in neurological cell models.

Mitochondria undergo dynamic morphological changes depending on cellular cues, stress, genetic factors, or disease. The structural complexity and disease-relevance of mitochondria have stimulated efforts to generate image analysis tools for describing mitochondrial morphology for therapeutic development. Using high-content analysis, we measured multiple morphological parameters and employed unbiased feature clustering to identify the most robust pair of texture metrics that described mitochondrial state.

Clinical Outcomes of Early Phenotype-Desirable Antimicrobial Therapy for Enterobacterales Bacteremia.

Importance: Initiating effective therapy early is associated with improved survival among patients hospitalized with gram-negative bloodstream infections; furthermore, providing early phenotype-desirable antimicrobial therapy (PDAT; defined as receipt of a β-lactam antibiotic with the narrowest spectrum of activity to effectively treat the pathogen's phenotype) is crucial for antimicrobial stewardship. However, the timing of targeted therapy among patients hospitalized with gram-negative bloodstream infections is not well understood.

Objective: To compare the clinical outcomes between patients who were hospitalized with Enterobacterales bloodstream infections receiving early vs delayed PDAT.

Incidence and variability in receipt of phenotype-desirable antimicrobial therapy for Enterobacterales bloodstream infections among hospitalized United States patients.

Background: Using a large, geographically diverse, hospital-based database in the United States (Premier PINC AI Healthcare Database), we aimed to describe the proportion and characteristics of patients receiving phenotype-desirable antimicrobial therapy (PDAT) among those hospitalized with Enterobacterales bloodstream infections.

Methods: Adult patients with an admission between January 1, 2017 and June 30, 2022 with ≥1 blood culture positive for , , , or and receiving an empiric antibiotic therapy on blood culture collection (BCC) Days 0 or 1 were included. Receiving PDAT (defined as receipt of any antimicrobial categorized as "desirable" for the respective phenotype) on BCC Days 0-2 was defined as receiving early PDAT.

Rab12 is a regulator of LRRK2 and its activation by damaged lysosomes.

Leucine-rich repeat kinase 2 (LRRK2) variants associated with Parkinson's disease (PD) and Crohn's disease lead to increased phosphorylation of its Rab substrates. While it has been recently shown that perturbations in cellular homeostasis including lysosomal damage can increase LRRK2 activity and localization to lysosomes, the molecular mechanisms by which LRRK2 activity is regulated have remained poorly defined. We performed a targeted siRNA screen to identify regulators of LRRK2 activity and identified Rab12 as a novel modulator of LRRK2-dependent phosphorylation of one of its substrates, Rab10.

CD98hc is a target for brain delivery of biotherapeutics.

Brain exposure of systemically administered biotherapeutics is highly restricted by the blood-brain barrier (BBB). Here, we report the engineering and characterization of a BBB transport vehicle targeting the CD98 heavy chain (CD98hc or SLC3A2) of heterodimeric amino acid transporters (TV). The pharmacokinetic and biodistribution properties of a CD98hc antibody transport vehicle (ATV) are assessed in humanized CD98hc knock-in mice and cynomolgus monkeys.

Optogenetic control of Wnt signaling models cell-intrinsic embryogenic patterning using 2D human pluripotent stem cell culture.

In embryonic stem cell (ESC) models for early development, spatially and temporally varying patterns of signaling and cell types emerge spontaneously. However, mechanistic insight into this dynamic self-organization is limited by a lack of methods for spatiotemporal control of signaling, and the relevance of signal dynamics and cell-to-cell variability to pattern emergence remains unknown. Here, we combine optogenetic stimulation, imaging and transcriptomic approaches to study self-organization of human ESCs (hESC) in two-dimensional (2D) culture.

A TREM2-activating antibody with a blood-brain barrier transport vehicle enhances microglial metabolism in Alzheimer's disease models.

Loss-of-function variants of TREM2 are associated with increased risk of Alzheimer's disease (AD), suggesting that activation of this innate immune receptor may be a useful therapeutic strategy. Here we describe a high-affinity human TREM2-activating antibody engineered with a monovalent transferrin receptor (TfR) binding site, termed antibody transport vehicle (ATV), to facilitate blood-brain barrier transcytosis. Upon peripheral delivery in mice, ATV:TREM2 showed improved brain biodistribution and enhanced signaling compared to a standard anti-TREM2 antibody.

Co-emergence of cardiac and gut tissues promotes cardiomyocyte maturation within human iPSC-derived organoids.

During embryogenesis, paracrine signaling between tissues in close proximity contributes to the determination of their respective cell fate(s) and development into functional organs. Organoids are in vitro models that mimic organ formation and cellular heterogeneity, but lack the paracrine input of surrounding tissues. Here, we describe a human multilineage iPSC-derived organoid that recapitulates cooperative cardiac and gut development and maturation, with extensive cellular and structural complexity in both tissues.

Axial elongation of caudalized human organoids mimics aspects of neural tube development.

Axial elongation of the neural tube is crucial during mammalian embryogenesis for anterior-posterior body axis establishment and subsequent spinal cord development, but these processes cannot be interrogated directly in humans as they occur post-implantation. Here, we report an organoid model of neural tube extension derived from human pluripotent stem cell (hPSC) aggregates that have been caudalized with Wnt agonism, enabling them to recapitulate aspects of the morphological and temporal gene expression patterns of neural tube development. Elongating organoids consist largely of neuroepithelial compartments and contain TBXT+SOX2+ neuro-mesodermal progenitors in addition to PAX6+NES+ neural progenitors.

From leisure to isolation: a call to explore hotel sectors' role during COVID-19 pandemic.

In a recent correspondence, authors discussed the role of private companies in fulfilling their corporate social responsibility (CSR) by coming up with their own vaccination program for their employees during the COVID-19 pandemic. This paper supports the invitation for companies to act in accordance with their CSR and by emphasizing the various roles of companies just like what selected hotels do as isolation and quarantine facilities during the pandemic. However, certain considerations and issues must also be addressed by hotel sectors in accomplishing their CSR especially in time of public health crisis.

Deep neural net tracking of human pluripotent stem cells reveals intrinsic behaviors directing morphogenesis.

Lineage tracing is a powerful tool in developmental biology to interrogate the evolution of tissue formation, but the dense, three-dimensional nature of tissue limits the assembly of individual cell trajectories into complete reconstructions of development. Human induced pluripotent stem cells (hiPSCs) can recapitulate aspects of developmental processes, providing an in vitro platform to assess the dynamic collective behaviors directing tissue morphogenesis. Here, we trained an ensemble of neural networks to track individual hiPSCs in time-lapse microscopy, generating longitudinal measures of cell and cellular neighborhood properties on timescales from minutes to days.

SARS-CoV-2 infection of human iPSC-derived cardiac cells reflects cytopathic features in hearts of patients with COVID-19.

Although coronavirus disease 2019 (COVID-19) causes cardiac dysfunction in up to 25% of patients, its pathogenesis remains unclear. Exposure of human induced pluripotent stem cell (iPSC)-derived heart cells to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) revealed productive infection and robust transcriptomic and morphological signatures of damage, particularly in cardiomyocytes. Transcriptomic disruption of structural genes corroborates adverse morphologic features, which included a distinct pattern of myofibrillar fragmentation and nuclear disruption.

Engineering the Spatiotemporal Mosaic Self-Patterning of Pluripotent Stem Cells.

Pluripotent stem cells (PSCs) possess the ability to self-organize into complex tissue-like structures; however, the genetic mechanisms and multicellular dynamics that direct such patterning are difficult to control. Here, we pair live imaging with controlled induction of gene knockdown by CRISPR interference (CRISPRi) to generate changes within subpopulations of human PSCs, allowing for control over organization and analysis of emergent behaviors. Specifically, we use forced aggregation of mixtures of cells with and without an inducible CRISPRi system to knockdown molecular regulators of tissue symmetry.

SARS-CoV-2 infection of human iPSC-derived cardiac cells predicts novel cytopathic features in hearts of COVID-19 patients.

Although COVID-19 causes cardiac dysfunction in up to 25% of patients, its pathogenesis remains unclear. Exposure of human iPSC-derived heart cells to SARS-CoV-2 revealed productive infection and robust transcriptomic and morphological signatures of damage, particularly in cardiomyocytes. Transcriptomic disruption of structural proteins corroborated adverse morphologic features, which included a distinct pattern of myofibrillar fragmentation and numerous iPSC-cardiomyocytes lacking nuclear DNA.

Single-Cell Determination of Cardiac Microtissue Structure and Function Using Light Sheet Microscopy.

Native cardiac tissue is composed of heterogeneous cell populations that work cooperatively for proper tissue function; thus, engineered tissue models have moved toward incorporating multiple cardiac cell types in an effort to recapitulate native multicellular composition and organization. Cardiac tissue models composed of stem cell-derived cardiomyocytes (CMs) require inclusion of non-myocytes to promote stable tissue formation, yet the specific contributions of the supporting non-myocyte population on the parenchymal CMs and cardiac microtissues have to be fully dissected. This gap can be partly attributed to limitations in technologies able to accurately study the individual cellular structure and function that comprise intact three-dimensional (3D) tissues.

Automated Design of Pluripotent Stem Cell Self-Organization.

Human pluripotent stem cells (hPSCs) have the intrinsic ability to self-organize into complex multicellular organoids that recapitulate many aspects of tissue development. However, robustly directing morphogenesis of hPSC-derived organoids requires novel approaches to accurately control self-directed pattern formation. Here, we combined genetic engineering with computational modeling, machine learning, and mathematical pattern optimization to create a data-driven approach to control hPSC self-organization by knock down of genes previously shown to affect stem cell colony organization, CDH1 and ROCK1.

Phenotypic Variation Between Stromal Cells Differentially Impacts Engineered Cardiac Tissue Function.

Understanding the relationship between parenchymal and supporting cell populations is paramount to recapitulate the multicellular complexity of native tissues. Incorporation of stromal cells is widely recognized to be necessary for the stable formation of stem cell-derived cardiac tissues; yet, the types of stromal cells used have varied widely. This study systematically characterized several stromal populations and found that stromal phenotype and morphology was highly variable depending on cell source and exerted differential impacts on cardiac tissue function and induced pluripotent stem cell-cardiomyocyte phenotype.

Spatiotemporal mosaic self-patterning of pluripotent stem cells using CRISPR interference.

Morphogenesis involves interactions of asymmetric cell populations to form complex multicellular patterns and structures comprised of distinct cell types. However, current methods to model morphogenic events lack control over cell-type co-emergence and offer little capability to selectively perturb specific cell subpopulations. Our system interrogates cell-cell interactions and multicellular organization within human induced pluripotent stem cell (hiPSC) colonies.

Regional Approaches to Expedited Drug Development and Review: Can Regulatory Harmonization Improve Outcomes?

Drug regulatory agencies around the world have implemented programs to expedite drug development and review for promising new products for serious diseases. These programs are all intended to minimize delays in patient access to innovative medicines, and have used broadly similar strategies to shorten drug development and review timelines. However, they differ in many key respects, and some stakeholders have suggested that these differences create unnecessary barriers in the development and approval process, possibly leading to delays in access.

Building with ions: towards direct write of platinum nanostructures using in situ liquid cell helium ion microscopy.

Direct write with a liquid precursor using an ion beam in situ, allows fabrication of nanostructures with higher purity than using gas phase deposition. Specifically, positively charged helium ions, when compared to electrons, localize the reaction zone to a single-digit nanometer scale. However, to control the interaction of the ion beam with the liquid precursor, as well as enable single digit fabrication, a comprehensive understanding of the radiolytic process, and the role of secondary electrons has to be developed.

Compromised Neurocircuitry in Chronic Blast-Related Mild Traumatic Brain Injury.

The aim of this study was to apply recently developed automated fiber segmentation and quantification methods using diffusion tensor imaging (DTI) and DTI-based deterministic and probabilistic tractography to access local and global diffusion changes in blast-induced mild traumatic brain injury (bmTBI). Two hundred and two (202) male active US service members who reported persistent post-concussion symptoms for more than 6 months after injury were recruited. An additional forty (40) male military controls were included for comparison.

Nanoforging Single Layer MoSe2 Through Defect Engineering with Focused Helium Ion Beams.

Development of devices and structures based on the layered 2D materials critically hinges on the capability to induce, control, and tailor the electronic, transport, and optoelectronic properties via defect engineering, much like doping strategies have enabled semiconductor electronics and forging enabled introduction the of iron age. Here, we demonstrate the use of a scanning helium ion microscope (HIM) for tailoring the functionality of single layer MoSe2 locally, and decipher associated mechanisms at the atomic level. We demonstrate He(+) beam bombardment that locally creates vacancies, shifts the Fermi energy landscape and increases the Young's modulus of elasticity.

Polarization Control via He-Ion Beam Induced Nanofabrication in Layered Ferroelectric Semiconductors.

Rapid advances in nanoscience rely on continuous improvements of material manipulation at near-atomic scales. Currently, the workhorse of nanofabrication is resist-based lithography and its various derivatives. However, the use of local electron, ion, and physical probe methods is expanding, driven largely by the need for fabrication without the multistep preparation processes that can result in contamination from resists and solvents.