Biology subjects

Gordon, H.

Publications and source records attributed to Gordon, H..

6 recordsLinked to original sources

bioRxiv2026

Viral reservoir status in small mammals emerges as a predictable life-history trait after correcting for surveillance bias

Small mammals, particularly rodents and shrews, act as primary reservoirs for Arenaviruses and Hantaviruses, zoonotic pathogens causing substantial global morbidity. However, our understanding of reservoir ecology is obscured by biased surveillance efforts, where sampling preferentially targets synanthropic species and high-income regions. It remains unclear whether observed patterns of reservoir competence, such as the association with synanthropy, are biological realities or artefacts of surveillance bias. We conducted a systematic review and data synthesis of global surveillance efforts (1960-2023), creating a harmonised database of over 590,000 recorded small mammals contributing 716,000 assay results. We then integrated this with macroecological trait data and phylogenetics to model reservoir probability using Bayesian phylogenetic dyadic generalised linear mixed models. We identified substantial taxonomic and geographic biases; surveillance is heavily skewed towards the Palearctic and widespread, large-bodied species, while 46% of host genera remain entirely unsampled. Geographically, surveillance intensity correlates strongly with accessibility and night-light intensity rather than host biodiversity. After statistically correcting for historical sampling volume, we demonstrate that reservoir status is a predictable biological trait. A fast pace of life (e.g., early maturity, large litters) is associated with an increased probability of reservoir status, independent of sampling effort. Synanthropy also remains a strong, independent predictor, indicating that commensal species act as genuine biological amplifiers in modified landscapes. Evolutionary analyses reveal a mosaic of broad lineage-level co-divergence punctuated by frequent, reactive host-switching. By projecting these models globally, we demonstrate that anthropogenic disturbance acts as an ecological filter, fundamentally challenging the assumption that pristine tropical ecosystems represent the highest intrinsic hazard for viral emergence.

ecology↗

bioRxiv2025

Genetic dissection of microglia cannibalism reveals an IL10 signaling axis controls microglia lifespan

The development of complex organs, like the brain, demands a robust system for tissue remodeling and cellular debris clearance. In the brain, this function is performed by microglia, which must clear diverse debris substrates, including that caused by cell death. Although the subsequent fate of these phagocytic microglia is a critical regulatory point that impacts whether the brain resolves a debris environment, the genetic mechanisms that control microglia fate after debris clearance remain mostly unknown. To address this, we conducted a large-scale CRISPR screen in zebrafish using a custom-built robotic confocal microscope. We selected candidate genes from a single-cell RNA sequencing dataset of embryonic mouse microglia. This screen identified several modulators of microglial lifespan and cannibalism that are enriched in mouse and zebrafish microglia, including interleukin-10 receptor beta (il10rb), a receptor subunit for the cytokine IL10. Perturbation of il10, il10rb, and downstream signaling molecules JAK/STAT in zebrafish reduced microglial death. Expression analysis in mouse and zebrafish confirmed that microglia express both il10 and il10rb. Given the established role of IL10 in lysosomal remodeling, we hypothesized that it regulates microglial survival through lysosomal acidification. While il10rb perturbation did not alter lysosome number or size, it caused a significant reduction in LysoTracker-positive lysosomes, indicating decreased lysosomal acidification. Inhibiting v-ATPase also reduced microglial death, reinforcing the link between lysosomal pH and cell fate. Our findings reveal a cytokine-regulated mechanism where lysosomal dynamics determine the survival of phagocytic microglia. We propose that a necroptosis-cannibalism process functions as a quality control mechanism for microglial turnover, which is critical for refining neuroimmune cell function in the brain.

neuroscience↗

bioRxiv2025

Protocol for the production of an Arenavirus and Hantavirus host-pathogen database: Project ArHa.

1Arenaviruses and Hantaviruses, primarily hosted by rodents and shrews, represent significant public health threats due to their potential for zoonotic spillover into human populations. Despite their global distribution, the full impact of these viruses on human health remains poorly understood, particularly in regions like Africa, where data is sparse. Both virus families continue to emerge, with pathogen evolution and spillover driven by anthropogenic factors such as land use change, climate change, and biodiversity loss. Recent research highlights the complex interactions between ecological dynamics, host species, and environmental factors in shaping the risk of pathogen transmission and spillover. This underscores the need for integrated ecological and genomic approaches to better understand these zoonotic diseases. A comprehensive, spatially and temporally explicit dataset, incorporating host-pathogen dynamics and human disease data, is crucial for improving risk assessments, enhancing disease surveillance, and guiding public health interventions. Such a dataset (ArHa) would also support predictive modelling efforts aimed at mitigating future spillover events. This paper proposes the development of this unified database for small-mammal hosts of Arenaviruses and Hantaviruses, identifying gaps in current research and promoting a more comprehensive understanding of pathogen prevalence, spillover risk, and viral evolution. 2 Strengths and Limitations of this studyO_LIThis dataset combines detailed spatial and temporal information, providing a unique resource for understanding geographic and temporal trends in Arenavirus and Hantavirus host-pathogen relationships. C_LIO_LIBy explicitly quantifying sampling biases and detection efforts, the dataset allows more robust and accurate asssessments of pathogen prevalence and distribution. C_LIO_LIThe dataset offers a platform for linking ecological data with human health outcomes, supporting the identification of spillover hotspots. C_LIO_LIThe dataset relies on published material, which may vary in terms of detail, accuracy and completeness. Missing or imprecise information may limit the reliability of subsequent analyses. C_LIO_LIThe dataset will be produced as a static resource which could limit its relevance over time as emerging data will not be added. C_LI

microbiology↗

bioRxiv2024

Deletion of the endothelial glycocalyx component endomucin leads to impaired glomerular structure and function

BackgroundEndomucin (EMCN), an endothelial-specific glycocalyx component, was found to be highly expressed by the endothelium of the renal glomerulus. We reported an anti-inflammatory role of EMCN and its involvement in the regulation of vascular endothelial growth factor (VEGF) activity through modulating VEGF receptor 2 (VEGFR2) endocytosis. The goal of this study is to investigate the phenotypic and functional effects of EMCN deficiency using the first global EMCN knockout mouse model. MethodsGlobal EMCN knockout mice were generated by crossing EMCN-floxed mice with ROSA26-Cre mice. Flow cytometry was employed to analyze infiltrating myeloid cells in the kidneys. The ultrastructure of the glomerular filtration barrier was examined by transmission electron microscopy, while urinary albumin, creatinine, and total protein levels were analyzed from freshly collected urine samples. Expression and localization of EMCN, EGFP, CD45, CD31, CD34, podocin, albumin, and -smooth muscle actin were examined by immunohistochemistry. Mice were weighed regularly, and their systemic blood pressure was measured using a non-invasive tail-cuff system. Glomerular endothelial cells and podocytes were isolated by fluorescence-activated cell sorting for RNA-seq. Transcriptional profiles were analyzed to identify differentially expressed genes in both endothelium and podocytes, followed by gene ontology analysis of up- and down-regulated genes. Protein levels of EMCN, albumin, and podocin were quantified by Western blot. ResultsEMCN-/- mice were viable with no gross anatomical defects in kidneys. The EMCN-/- mice exhibited increased infiltration of CD45+ cells, with an increased proportion of Ly6GhighLy6Chigh myeloid cells and higher VCAM-1 expression. EMCN-/- mice displayed albuminuria with increased albumin in the Bowmans space compared to the EMCN+/+ littermates. Glomeruli in EMCN-/- mice revealed fused and effaced podocyte foot processes and disorganized endothelial fenestrations. We found no significant difference in blood pressure between EMCN knockout mice and their wild-type littermates. RNA-seq of glomerular endothelial cells revealed downregulation of cell-cell adhesion and MAPK/ERK pathways, along with glycocalyx and extracellular matrix remodeling. In podocytes, we observed reduced VEGF signaling and alterations in cytoskeletal organization. Notably, there was a significant decrease in both mRNA and protein levels of podocin, a key component of the slit diaphragm. ConclusionOur study demonstrates a critical role of the endothelial marker EMCN in supporting normal glomerular filtration barrier structure and function by maintaining glomerular endothelial tight junction and homeostasis and podocyte function through endothelial-podocyte crosstalk.

pathology↗

bioRxiv2023

Single cell sequencing data identify distinct B cell and fibroblast populations in stricturing Crohns disease

We used human full thickness Crohns disease (CD) small bowel resection specimens and single cell RNA sequencing to identify potential therapeutic targets for stricturing (S)CD. Using an unbiased approach, 16 cell lineages were assigned within 14,539 sequenced cells from patient-matched SCD and non-stricturing (NSCD) preparations. SCD and NSCD contained identical cell types. Amongst immune cells, B cells and plasma cells were selectively increased in SCD samples. B cell subsets suggested formation of tertiary lymphoid tissue in SCD and compared with NSCD there was an increase in IgG, and a decrease in IgA plasma cells, consistent with their potential role in CD fibrosis. Two Lumican-positive fibroblast subtypes were identified and subclassified based on expression of selectively enriched genes as fibroblast clusters (C)12 and C9. Cells within these clusters expressed the profibrotic genes Decorin (C12) and JUN (C9). C9 cells expressed ACTA2; ECM genes COL4A1, COL4A2, COL15A1, COL6A3, COL18A1 and ADAMDEC1; LAMB1 and GREM1. GO and KEGG Biological terms showed extracellular matrix, stricture organisation and regulation of WNT pathway genes are associated with the C12 and C9 gene sets. Trajectory and differential gene analysis of C12 and C9 identified four sub-clusters. Intra sub-cluster gene analysis detected co-regulated gene modules that aligned along predicted pseudotime trajectories and identified CXCL14 and ADAMDEC1 as key module markers. Our findings support further investigation of fibroblast heterogeneity and interactions with local and circulating immune cells at earlier time points in fibrosis progression. Breaking these interactions by targeting one or other population may improve therapeutic management for SCD.

genomics↗

bioRxiv2023

A paradox promoted by microglia cannibalism shortens the lifespan of developmental microglia

The overproduction of cells and subsequent production of debris is a universal principle of neurodevelopment. Here we show an additional feature of the developing nervous system that causes neural debris - promoted by the sacrificial nature of embryonic microglia that irreversibly become phagocytic after clearing other neural debris. Described as long-lived, microglia colonize the embryonic brain and persist into adulthood. Using transgenic zebrafish to investigate the microglia debris during brain construction, we identified that unlike other neural cell-types that die in developmental stages after they have expanded, necroptosis-dependent microglial debris is prevalent when microglia are expanding in the zebrafish brain. Time-lapse imaging of microglia demonstrates that this debris is cannibalized by other microglia. To investigate features that promote microglia death and cannibalism, we used time-lapse imaging and fate-mapping strategies to track the lifespan of individual developmental microglia. These approaches revealed that instead of embryonic microglia being long-lived cells that completely digest their phagocytic debris, once most developmental microglia in zebrafish become phagocytic they eventually die, including ones that are cannibalistic. These results establish a paradox -- which we tested by increasing neural debris and manipulating phagocytosis -- that once most microglia in the embryo become phagocytic, they die, create debris and then are cannibalized by other microglia, resulting in more phagocytic microglia that are destined to die.

developmental biology↗