Biology subjects

Stow, J. L.

Publications and source records attributed to Stow, J. L..

4 recordsLinked to original sources

bioRxiv2026

E-Selectin Orchestrates IL-1B-Dependent Neuroinflammation via NLRP3 in Vincristine-Induced Neuropathy

Vincristine-induced peripheral neuropathy (VIPN) is a frequent and dose-limiting complication of cancer therapy, yet the upstream mechanisms coupling vascular activation to neuroinflammation remain poorly defined. Here we identify E-selectin as a critical orchestrator of vincristine-induced neuropathy. Systematic interrogation of endothelial adhesion molecules in a murine model of VIPN revealed that blockade of E-selectin, but not ICAM-1, PECAM-1 or P-selectin, completely prevented mechanical hypersensitivity and markedly reduced F4/80 immune cell accumulation in dorsal root ganglia and peripheral nerves. Genetic deletion of E-selectin conferred equivalent protection, despite the absence of structural loss of intraepidermal or myelinated fibres, indicating a predominantly functional neuroimmune pathology. Spatial transcriptomics demonstrated that vincristine induces a conserved stress and neuroinflammation-associated transcriptional programme in dorsal root ganglia, with immune and stromal populations acting as dominant signalling hubs. Genetic or pharmacological perturbation of E-selectin did not abolish injury-associated pathways but redistributed cell-cell communication networks, reducing immune-cell dominance and reshaping interferon and metabolic signalling states without inducing Sele expression. Mechanistically, E-selectin exerted non-canonical effects beyond endothelial adhesion. Local E-selectin administration was sufficient to induce macrophage-dependent mechanical hypersensitivity that was abolished in Fut4/7-deficient mice and following phagocyte depletion. In macrophages, E-selectin enhanced vincristine-driven NF-{kappa}B activation, NLRP3 inflammasome assembly and IL-1{beta} release. Together, these findings position E-selectin as an upstream regulator of IL-1{beta}-dependent neuroinflammation in VIPN and identify selective targeting of E-selectin-mediated immune-neuron interactions as a therapeutic strategy for chemotherapy-induced neuropathy.

neuroscience↗

bioRxiv2024

Macrophage migration-dependent retraction fibers and migrasomes - a structural basis for spatiotemporal cytokine secretion.

Migrating cells leave behind trails of matrix-bound retraction fibers and migrasomes, but their cell-specific physiological functions are largely unknown. We comprehensively characterize retraction fibers and migrasomes of migrating macrophages in mouse and zebrafish in vitro and in vivo models. These structures share common and macrophage-centric components of tetraspanin enriched microdomains (TEMs) including tetraspanin 4 (TSPAN4), the integrin CD11b and the pTRAP, SCIMP; like TSPAN4, we show that SCIMP expression modulates retraction fiber and migrasome formation. In immune-activated migrating macrophages, rear-positioned recycling endosomes regulate the secretory trafficking of newly synthesized inflammatory cytokines into retraction fibers and migrasomes. Transmembrane TNF is delivered via SNARE-mediated carriers to the cell surface and to the surfaces of both retraction fibers and migrasomes, from where it can be released. Retraction fibers are thus newly identified here as cytokine secretion sites, and along with migrasomes they allow migrating macrophages to secrete more cytokine compared to stationary cells. Whereas cytokine secretion has been viewed as a process of ad hoc diffusion, instead, we reveal a new mechanism of migration-dependent, localized deposition and spatiotemporal release of bioactive cytokines from RFs and migrasomes. Cytokine deployment is thus organized in a constrained manner facilitating direct influence on local inflammatory responses.

cell biology↗

bioRxiv2021

Macropinosomes host TLR9 signaling and regulation of inflammatory responses in microglia

To support their innate immune and scavenging functions in the brain, microglia are equipped with Toll-like receptors (TLRs), including the intracellular receptor TLR9, which is activated by microbial CpG-rich DNA. Macropinocytosis is an abundant and inducible pathway in microglia for fluid-phase uptake and ingestion of microbes and cell debris. TLR9 signaling has been ascribed to endolysosomes, particularly lysosomes, which it accesses through direct transport or via internalization from the surface. Here, TLR9 and exogenous CpG-DNA are localized during uptake into fluid-filled macropinosomes, upon upregulated macropinocytosis, where acidic and proteolytic environments support MyD88-induced signaling. Macropinosomes represent an abundant pathway for endolysosomal traffic of TLR9 but are also a much more exposed site for nucleic acid activation of the receptor with a risk of excessive inflammation. To constrain TLR9 inflammation, macropinosomes also house the TLR9 co-receptor LRP1 and regulators Rab8a and PI3K{gamma} which augment Akt signaling and favor anti-inflammatory cytokine production. Macropinosomes and their inflammatory regulators are therefore important components of TLR9 pathways in microglia that are poised for surveillance and protection in the CNS.

cell biology↗

bioRxiv2020

LLAMA: a robust and scalable machine learning pipeline for analysis of cellsurface projections in large scale 4D microscopy data

We present LLAMA, a pipeline for systematic analysis of terabyte scale 4D microscopy datasets. Analysis of individual biological structures in imaging at this scale requires efficient and robust methods which do not require human micromanagement or editing of outputs. To meet this challenge, we use a machine learning method for semantic segmentation, followed by a robust and configurable object separation and tracking algorithm, and the generation of detailed object level statistics. Advanced visualisation is a key element of LLAMA: we provide a specialised software tool which supports quality control and optimisation as well as visualisation of outputs. LLAMA was used in a quantitative analysis of macrophage surface membrane projections (filopodia, ruffles, tent-pole ruffles) examining the differential effects of two interventions: lipopolysaccharide (LPS) and macrophage colony stimulating factor (CSF-1). Distinct patterns of increased activity were identified. In addition, a continuity of behaviour was found between tent pole ruffling and wave-like ruffling, further defining the role of filopodia in ruffling.

cell biology↗