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Biology subjects

Goldsworthy, S.

Publications and source records attributed to Goldsworthy, S..

4 recordsLinked to original sources

Multi-omics reveals a monocyte-macrophage-fibroblast axis in post-COVID-19 fibroinflammatory lung remodelling

Post-COVID-19 residual lung abnormalities (RLA) are associated with persistent respiratory symptoms and radiological changes, yet the underlying mechanisms remain unclear. We performed integrated multi-omic profiling of paired bronchoalveolar lavage and blood samples from patients with post-COVID-19 RLA and healthy controls, combining single-cell RNA sequencing, CITE-seq, single-cell T cell receptor sequencing, bronchoalveolar lavage fluid proteomics and functional fibroblast assays. In post-COVID-19 RLA lungs, we identified an increased abundance of profibrotic SPP1hi monocyte-derived alveolar macrophages, arising from an expanded circulating HLA-DRlowCD163+PDE4Dhi classical monocyte progenitor population, supporting a blood-lung myeloid axis. Cell-cell communication modelling positioned macrophages as central hubs of immune-stromal crosstalk, promoting monocyte recruitment with profibrotic priming, and fibroblast activation. Proteomic analysis of bronchoalveolar lavage fluid from post-COVID-19 RLA and idiopathic pulmonary fibrosis, compared with healthy controls, revealed shared and distinct signatures. These alveolar proteins in post-COVID-19 RLA were predominantly attributed to myeloid cells and predicted to engage fibroblast receptors. Bronchoalveolar lavage fluid induced fibroblast proliferation, differentiation and collagen deposition in vitro, with proliferation attenuated by the antifibrotic drug nintedanib. We also identified compartment-specific lymphoid dysregulation, including depletion of mucosal-associated invariant T (MAIT) cells in both the lung and blood, decreased natural killer (NK) cells with oligoclonal T cell expansion in the lung, and expansion of regulatory and cytotoxic T cells in the blood. These findings support a persistent monocyte-macrophage-fibroblast axis linking immune dysregulation to fibroproliferative remodelling after COVID-19 and highlights candidate therapeutic targets for post-viral lung fibrosis. We provide a publicly available atlas (on publication).

systems biology↗

Lysosomal stress induces amyloid-β aggregate release and reactive transformation in human astrocytes

Astrocytes are essential for brain homeostasis and are involved in amyloid-{beta} (A{beta}) clearance, but whether they can produce and release A{beta} aggregates remains unclear. Using human iPSC-derived astrocytes, we show that astrocytes cell autonomously generate small, diffusible A{beta} aggregates under baseline conditions. By combining ultrasensitive single-molecule imaging (DNA-PAINT) and immunoassays, we detect intracellular aggregates and their release into the media. Notably, lysosomal membrane damage induced by L-leucyl-L-leucine methyl ester (LLOMe) significantly increases A{beta} aggregate secretion without altering their size or morphology. Transcriptomic analysis and cytokine profiling reveal that lysosomal stress triggers a reactive astrocyte phenotype marked by upregulation of inflammatory genes and secreted cytokines. These findings suggest that astrocytes are not merely passive A{beta} scavengers but can actively contribute to extracellular A{beta} accumulation under lysosomal stress. Our study highlights astrocytes as active players in Alzheimers disease pathology.

neuroscience↗

MicroRNA miR-92b-3p regulation of a cardiovascular gene regulatory network in the developing branchial arches

Vertebrate branchial arches (BAs) are a developmental paradigm, undergoing coordinated differentiation and morphogenesis to form various adult derivative tissues. MicroRNAs can strengthen gene regulatory networks (GRNs) to promote developmental stability. To interrogate the contribution of microRNAs to BA development, we generated a novel microRNA-sequencing dataset from mouse BAs. We identified 550 expressed microRNAs, of which approximately 20% demonstrate significant differential expression across BA domains. The three most posterior BAs and the connecting outflow tract (PBA/OFT) are enriched in biological processes linked to cardiovascular development. We identified enriched predicted microRNA-target interactions with PBA/OFT upregulated cardiovascular genes and validated transcripts encoding for two fundamental cardiac transcription factors (TFs), Gata6 and Tbx20, as targets of miR-92b-3p. Furthermore, we demonstrated that miR-92b-3p can downregulate endogenous GATA6 and TBX20 in human embryonic stem cells (hESCs) undergoing cardiomyocyte differentiation, consistent with conservation of these microRNA-target interactions in a cardiogenic setting. miR-92b-3p has previously been shown to target two other cardiac TFs, Hand2 and Mef2D. Therefore, we hypothesise that miR-92b-3p acts to stabilise cardiovascular GRNs during PBA/OFT development, through acting in multiple microRNA-mediated coherent feedforward loops.

developmental biology↗

Recent demographic histories and genetic diversity across pinnipeds are shaped by anthropogenic interactions and mediated by ecology and life-history

A central paradigm in conservation biology is that population bottlenecks reduce genetic diversity and negatively impact population viability and adaptive potential. In an era of unprecedented biodiversity loss and climate change, understanding both the determinants and consequences of bottlenecks in wild populations is therefore an increasingly important challenge. However, as most studies have focused on single species, the multitude of potential drivers and the consequences of bottlenecks remain elusive. Here, we used a comparative approach by integrating genetic data from over 11,000 individuals of 30 pinniped species with demographic, ecological and life history data to elucidate the consequences of large-scale commercial exploitation by 18th and 19th century sealers. We show that around one third of these species exhibit strong genetic signatures of recent population declines, with estimated bottleneck effective population sizes reflecting just a few tens of surviving individuals in the most extreme cases. Bottleneck strength was strongly associated with both breeding habitat and mating system variation, and together with global abundance explained a large proportion of the variation in genetic diversity across species. Overall, there was no relationship between bottleneck intensity and IUCN status, although three of the four most heavily bottlenecked species are currently endangered. Our study reveals an unforeseen interplay between anthropogenic exploitation, ecology, life history and demographic declines, sheds new light on the determinants of genetic diversity, and is consistent with the notion that both genetic and demographic factors influence population viability.

evolutionary biology↗