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Biology subjects

Guiducci, C.

Publications and source records attributed to Guiducci, C..

3 recordsLinked to original sources

Bexobrutideg: A Selective, Catalytic Degrader of Bruton's Tyrosine Kinase Overcomes Inhibitor Resistance and Suppresses Autoantibody-Mediated Disease

Brutons tyrosine kinase (BTK) transduces B-cell receptor (BCR), Toll-like receptor (TLR), and Fc receptor (FcR) signaling, and overactivation of these pathways drives B-cell malignancies and antibody-mediated autoimmune disease. Small molecule inhibitors block the enzymatic functions of BTK, but this inhibition is undermined by resistance mutations, several of which abolish BTKs kinase activity yet promote oncogenic signaling through BTK scaffolding functions. We report the discovery and characterization of bexobrutideg (NX-5948), a heterobifunctional degrader that recruits cereblon (CRBN) to selectively degrade BTK while sparing molecular glue neosubstrates. We demonstrate that bexobrutideg acts catalytically, degrading thousands of copies of BTK per molecule per hour, and this event-driven pharmacology renders it resilient to mutations that confer resistance to both covalent- and noncovalent-inhibitors. Bexobrutideg is orally bioavailable, driving deep and durable BTK degradation across species. Bexobrutideg demonstrates strong efficacy in wild-type and ibrutinib-resistant lymphoma models and robustly suppresses pathway activation in models of autoimmune disease.

cancer biology↗

A Microfluidic Platform for Whole-Membrane Integrity Profiling in Live Neuronal Cells

Structural and functional compromise of the cellular membrane are central mechanisms in the pathogenesis of numerous diseases, including neurodegenerative disorders such as Alzheimers and Parkinsons disease. However, existing techniques for assessing membrane integrity often lack the ability to provide dynamic, whole-cell measurements and are limited to localized damage detection or population-level analysis. There is a growing need for methods capable of monitoring membrane integrity over time at the single-cell level and across the entire membrane surface. In this study, we present a microfluidic platform for real-time, label-free assessment of membrane integrity by analyzing dielectric properties. We apply this system to investigate how different aggregated forms of -Synuclein (aSyn), a protein that plays a central role in the pathogenesis of Parkinsons disease and disrupts neuronal membranes. Our platform integrates electrokinetic microdevices with 3D microelectrodes and imaging, enabling continuous analysis of up to 30 live neuronal cells per hour under flow. By measuring electrorotation responses, we quantify changes in plasma membrane capacitance in response to monomeric, oligomeric, and fibrillar aSyn. This approach allows direct, time-resolved comparison of membrane-disruptive effects across different aSyn conformations with single-cell resolution and whole-membrane sensitivity.

bioengineering↗

MarrowDLD: a microfluidic method for label-free retrieval of fragile bone marrow cells

Functional bone marrow studies have focused primarily on hematopoietic progenitors, leaving limited knowledge about other fragile populations, such as bone marrow adipocytes (BMAds) and megakaryocytes. The isolation of these cells is challenging due to rupture susceptibility and large size. We introduce here a label-free cytometry microsystem, MarrowDLD, based on deterministic lateral displacement. MarrowDLD enables the isolation of fragile cells based on intrinsic size properties while preserving their viability and functionality. Bone marrow adipocytes, obtained from mouse and human stromal line differentiation, as well as megakaryocytes, from primary human CD34+ hematopoietic stem and progenitor cells, were used for validation. Precise micrometer-range separation cutoffs were adapted for each cell type. Cells were sorted directly in culture media, without pre-labeling steps, and with real-time imaging for quality control. At least 106 cells were retrieved intact per sorting round. Our method outperformed two FACS instruments in purity and yield, particularly for large cell size fractions. MarrowDLD represents a non-destructive sorting tool for fragile cells, facilitating the separation of phenotypically pure populations of BMAds and megakaryocytes to further investigate their physiological and pathological roles.

bioengineering↗