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Rabinowitz, G.

Publications and source records attributed to Rabinowitz, G..

3 recordsLinked to original sources

APOE4 promotes cerebrovascular fibrosis and amyloid deposition via a pericyte-to-myofibroblast transition

Cerebrovascular disease is a major but poorly understood feature of Alzheimer's disease (AD). The strongest genetic AD risk factor, APOE4, is associated with cerebrovascular degeneration, including vascular amyloid deposition and fibrosis. To uncover how APOE4 promotes cerebrovascular pathology, we assembled a single-cell transcriptomic atlas of human brain vasculature. In APOE4 carriers, pericyte abundance was significantly reduced and accompanied by the emergence of a myofibroblast-like cell population co-expressing contraction and extracellular matrix genes. Immunostaining confirmed non-vascular myofibroblasts in APOE4 human and mouse brains. We show that APOE4 pericytes transition into myofibroblasts that secrete fibronectin, which promotes vascular amyloid accumulation. Computational and experimental analyses identified elevated TGF-{beta} signaling as the driver of this pericyte-to-myofibroblast transition. Inhibition of TGF-{beta} restored pericyte coverage and reduced vascular fibrosis and amyloid to APOE3 levels, revealing a targetable mechanism linking APOE4 to cerebrovascular pathology in AD.

neuroscience↗

Single-Cell Spatial Mapping of Human Kidney Development Reveals the Critical Role of the Local Microenvironment in Cell Fate Decisions

Cell-cell interactions play a pivotal role in organ development, yet these communications have previously been studied one interaction at a time in model organisms, leaving a gap in our understanding of the cellular interplay in human development. To address this, we investigated human kidney development using single-cell RNA sequencing and spatial transcriptomics, analyzing over 500,000 cells. By mapping gene expression and differentiation trajectories in histologic space, we define the spatial organization of kidney development. Our analysis revealed newfound plasticity, showing that nephron progenitor cells undergo an early fate decision between renal corpuscle and tubular lineages. However, this choice is later reversed with some mature tubule cells transitioning back to a renal corpuscle fate. Further, through a genome-wide, spatially-aware cell-cell interaction analysis, we identified specific ligands and neighboring cell signals that create biologically meaningful cellular neighborhoods and mediate cell fate choices, offering a blueprint to understand the coordination of human development at scale.

genomics↗

Amniotic Fluid Organoids As Personalized Tools For Real-Time Modeling Of The Developing Fetus

Despite biomedical advances, major knowledge gaps regarding human development remain, and many developmental disorders lack effective treatment, representing a huge clinical burden. This results from fetuses being largely inaccessible for analysis. Here, we employ fetal cells in human amniotic fluid (AF) to establish personalized fetal kidney and lung organoids (AFKO and AFLO, respectively), recapitulating fetal organs at single-cell resolution. AFKO harbor key fetal kidney cell populations, including nephrogenic, urothelial and stromal, endocytose albumin, and model PAX2-related anomalies. Strikingly, upon injection into the nephrogenic cortex of human fetal kidney explants, AFKO-derived progenitors integrate into the host progenitor niche and contribute to developing nephrons. AFLO comprise alveolar cells and most airway cell types in a typical pseudostratified structure, upregulate surfactant expression upon corticosteroid treatment, and show functional CFTR channels. Overall, this platform represents a new personalized tool that can be applied to virtually any fetus in real-time, affording unprecedented options in studying development, uncovering mechanisms of in utero pathologies (e.g., congenital anomalies, infections or chemical teratogens) deciphering the developmental origins of chronic diseases, and tailoring treatments for these pathologies, as well as for prematurity-related complications. Importantly, since AF contains cells from additional tissues (e.g., skin and gastrointestinal tract), and is derived in a procedure already performed in many patients, this platform may well become a broadly applicable tool in fetal medicine.

developmental biology↗